Pathophysiology Lesson 9
Most fungal infections are asymptomatic. When are these infections severe or potentially fatal?
heavy exposure immune deficiency (e.g., HIV) progressive, unrecognized or treated infection
attachment protein that allows the influenza virus to enter epithelial cells in the respiratory tract
hemagglutinin
Pneumonias are commonly categorized as being either community-acquired or _____-acquired.
hospital
increase in the carbon dioxide content of the arterial blood
hypercapnia
reduction in blood O2 levels
hypoxemia
reduced or deficient oxygenation
hypoxia
The body compensates for chronic hypoxemia by _____. Select all that apply.
increased production of red blood cells pulmonary vasoconstriction increased ventilation
viral and mycoplasma infections
neuraminidase
symptoms that develop when substances, released by some cancer cells that disrupt normal function
paraneoplastic syndrome
A/an ________ is an abnormal collection of fluid in the pleural cavity.
pleural effusion
A/An ______ develops when a blood-borne substance lodges in a brach of the pulmonary artery and obstructions blood flow.
pulmonary embolism
In the early stages, influenza symptoms cannot be distinguished from other respiratory viral infections. What is the distinguishing feature of an influenza viral infection that makes it different from other respiratory viral infections?
rapid onset of profound malaise
The term __________ refers to an inflammation of the nasal passages and sinusitis to an inflammation of the paranasal sinuses.
rhinitis
Cor pulmonale refers to _____ heart failure resulting from primary lung disease and involves hypertrophy and eventual failure of that ventricle.
right-sided
A/an ________ is a type of spontaneous pneumothorax that occurs because of lung disease.
secondary pneumothorax
A 23-year-old woman goes to the drug store to buy a medication to ease the symptoms of her cold. Her friends have told her to buy a medication with an antihistamine and decongestant. The woman talks with the pharmacist, who has known her for many years. The pharmacist recommends that she not buy a cold medication with a decongestant. Why would he make that recommendation?
she has hyperthyroidism which is not advised with antihistamines
A/an _______ is the rupture of an air-filled bleb on the lung surface causing ipsilateral chest pain, tachypnea, chest asymmetry, hyperresonant sound with percussion, and diminished or absent breath sounds over the area of pneumothorax.
spontaneous pneumothorax
audible crowing sound during inspiration
stridor
A/an _______ is a life-threatening condition, occurs when the intrapleural pressure exceeds atmospheric pressure, permitting air to enter but not leave the pleural space.
tension pneumothorax
The common cold is a viral infection of the __________ respiratory tract.
upper
reflects the body's extraction and utilization of O2 at tissue levels
venous oxygen
movement of gas into or out of the lungs
ventilation
What is the pathogenesis?
- Bronchogenic carcinoma, arising from the bronchial epithelium is the most common type of malignant lung tumor - the first change in the lungs is usually metaplasia, a change in the epithelial tissue, associated with smoking or chronic irritation, which is reversible if the irritation ceases - stratified squamous epithelium replaces the normal protective, ciliated, pseudostratified epithelium leaving the lung tissue more vulnerable to irritants and inflammation from smoking - various chemicals in cigarette smoke are also carcinogenic and act as initiators and promoters. Dysplasia or carcinoma in situ then develops - these changes are difficult to detect - the major subtypes include small cell lung cancer and non-small cell lung cancer
SCLC treatment:
- Chemotherapy - multidrug therapy - Radiation - adjuvant therapy with chemotherapy - Prophylactic cranial irradiation because of the high occurrence of metastasis to brain.
Paraneoplastic syndrome is more often associated with SCLC and indicated by the signs of an endocrine disorder related to the specific hormone secreted; however, NSCLC also synthesizes bioactive products causing some paraneoplastic syndromes:
- Hypercalcemia caused by parathyroid-like hormone production occurs most commonly in squamous cell carcinoma (NSCLC) - Cushing's syndrome (ectopic adrenocorticotropic hormone (ACTH)) and syndrome of inappropriate antidiuretic hormone production (SIADH) most commonly occur in SCLC - Neuromuscular syndrome (Eaton-Lambert syndrome) - weakness and wasting of proximal muscles of the pelvic and shoulder girdles with decreased DTR without sensory changes occurs in SCLC - Hematologic disorders: migratory thrombophlebitis, nonbacterial endocarditis, disseminated intravascular coagulation (DIC) - highly associated with adenocarcinoma (NSCLC)
Involvement of the lung and adjacent structures from irritation and airway obstruction:
- Persistent cough, dyspnea, and wheezing - Hemoptysis (tumors erodes lung tissue) - Pleural effusion, pneumothorax, or hemothorax (tumors adjacent to pleura) - Dull, intermittent, retrosternal pain (tumor pressing on mediastinum) - Anorexia and weight loss - generalized cancer signs/symptoms
What are treatment modalities?
- Radiofrequency ablation (RFA) can be used to destroy a single small tumor. Surgical resection or lobectomy may be performed on localized lesions - Chemotherapy and radiation may be used in conjunction with surgery or as palliative treatment - many tumors are not responsive to this therapy - Photodynamic therapy (a chemical is injected and migrates to tumor cells, where it is activated by laser light and destroys the cancer cells) is sometimes effective. Prognosis is poor unless the tumor is in a very early stage of development
Tension Pneumothorax
- a tension pneumothorax results from air entering the pleural cavity through the wound with inhalation and cannot leave upon exhalation - increases pressure on the organs of the thoracic cage - unless the pressure is relieved, tension pneumothorax is fatal
Manifestations of ARDS
- acute hypoxemia may cause dyspnea, restlessness, and anxiety - the patient will present with confusion or alteration of consciousness, cyanosis, tachypnea, tachycardia, and diaphoresis - cardiac arrhythmia and coma can result. Airway closure causes crackles, detected during chest auscultation; the crackles (rales) are typically diffuse but sometimes worse at the lung bases - jugular venous distention (JVD) occurs with right ventricular failure
What are the types of bronchial asthma?
- asthma involves periodic episodes of severe but reversible bronchial obstruction in a person with hypersensitive or hyper-responsive airways - frequent repeated attacks of acute asthma may lead to irreversible damage in the lungs and the development of chronic asthma - acute attacks may continue to be superimposed on the chronic condition
Causes of ARDS:
- causes of ARDS may involve direct lung injury (e.g., pneumonia, acid aspiration) or indirect lung injury (e.g., sepsis, pancreatitis, massive blood transfusion, nonthoracic trauma) - sepsis and pneumonia account for about 60% of cases
Who is likely to get a severe fungal infection of the lungs?
- immunocompromised
Intrinsic Asthma
- intrinsic asthma has an onset during adulthood. In this disease other types of stimuli target hyper-responsive tissues in the airway, initiating the attack - these stimuli include respiratory infections, exposure to cold, exercise, drugs such as aspirin, stress, and inhalation of irritants, such as cigarette smoke - many have a combination of the two types
Anatomic location - acute bacterial pneumonia
- lobar - consolidation of a part or all of a lung lobe - bronchopneumonia - patchy consolidation involving more than one lobe
Sputum
- mucoid discharge, from the respiratory tract may have significant characteristics depending on the abnormality causing it - normal secretions are relatively thin, clear, and colorless or cream color - yellowish-green, cloudy, and thick mucus is often associated with a bacterial infection
Mycobacterium tuberculosis
- mycobacterium tuberculosis is protected in a strong coating that enables it to live outside the body for a lengthy period of time, it is waxy - infected droplets that are coughed or sneezed may dry up and remain on inanimate objects - even dust - the tuberculosis bacteria can be killed by bactericidal solutions or by direct sunlight
The clinical manifestations of idiopathic pulmonary fibrosis are:
- nonspecific and can be shared with many pulmonary and cardiac diseases - most patients present with a gradual onset of more than 6 months of exertional dyspnea and/or a nonproductive cough - approximately 5% of patients have no presenting symptoms when idiopathic pulmonary fibrosis is serendipitously diagnosed
Drugs used in symptomatic treatment include...
- nonsteroidal anti-inflammatory drugs, antihistamines, and anticholinergic nasal solutions - these agents have no preventive activity and appear to have no impact on complications - the combined effect of NSAIDs and antihistamines often relieves nasal obstruction; therefore, decongestion therapy is rarely needed - however, oral decongestants (pseudoephedrine) and topical decongestants (oxymetazoline and phenylephrine) are commonly used for symptomatic relief - first-generation antihistamines reduce rhinorrhea by 25-35%, as do topical anticholinergics and ipratropium bromide - second-generation or non-sedating antihistamines appear to have no effect on common cold symptoms - corticosteroids may actually increase viral replication and have no impact on cold symptoms
The individual prognosis is often linked to...
- the severity and outcome of the underlying disease and to whether a reversal of factors affecting the patient's immune status is possible
Treatment of pulmonary embolism
- treatment of pulmonary embolism mainly involves anticoagulant therapy to prevent recurrences of emboli - acute cases may call for thrombolytic therapy - interventional therapy includes surgical removal of clots, located by angiography, from the pulmonary artery or its principal branches - various methods of occluding the inferior vena cava in cases where emboli are thought to arise in the lower part of the body are occasionally used - occlusion blocks the pathway for emboli and forces the blood to return to the heart through small collateral veins
Tuberculosis
- tuberculosis (TB) is a bacterial infection caused by the Mycobacterium tuberculosis - it is acquired by breathing air that is infected with the bacteria and spread by coughing and sneezing - in a healthy individual, TB is asymptomatic - that's why testing is needed to identify the presence of the disease - if symptoms do appear, they are usually vague and can include weight loss, fatigue, and anorexia - as the disease progresses, the individual may become symptomatic with a chronic productive cough, dyspnea, fever, and night sweats
The airways of the respiratory system are divided into two sections:
- upper respiratory system: nasal cavities, oral cavity, sinuses, pharynx, and larynx - lower respiratory system: trachea, bronchi, bronchioles, and alveoli
What are the mechanisms of ventilation?
- ventilation is the movement of air into and out of the respiratory system - requiring both inhalation and exhalation - chemosensory receptors in spinal fluid and the carotid and aortic arteries, arterial carbon dioxide tension, and oxygen deficiency participate in the control of ventilation - ventilation is increased or decreased to meet body requirements as the receptors detect increases or decreases in carbon dioxide and/or oxygen levels - because the respiratory control center is located in the medulla of the brain, respiratory or neurologic diseases can interfere with normal ventilation
T lymphocyte activation
- while the precise mechanism for a similar response in individuals with intrinsic asthma has not been determined, research suggests that chronic T lymphocyte activation, possibly due to an internal antigen, is the cause - the tissues are hyper-responsive, and an underlying chronic inflammation or imbalance in autonomic innervation of the tissues is also suspected
Types of Sputum
- yellowish-green, cloudy, thick: bacterial infection - rusty or dark-colored: pneumococcal pneumonia - large amount purulent with foul odor: bronchiectasis - thick, tenacious: asthma, cystic fibrosis - blood-tinged (hemoptysis) and frothy: pulmonary edema - blood-tinged: chronic cough and irritation with rupture of superficial capillaries or tuberculosis
1) What are some risk factors for lung cancer? 2) What is the prognosis for large cell carcinoma of the lung? 3) What are the 3 types of non-small cell lung cancer? 4) What are 2 manifestations of mediastinal invasion? 5) What are 3 paraneoplastic manifestations of lung cancer?
1) Cigarette smoking, second-hand smoke, and occupational or industrial exposure to carcinogens. 2) It spreads early to distant sites and has a poor prognosis. 3) squamous cell carcinoma, adenocarcinoma, large cell carcinoma 4) hoarseness and superior vena cava syndrome 5) Cushing syndrome from ACTH secretion Eaton-Lambert syndrome with weakness and wasting of proximal muscles of pelvic and shoulder girdles Hematologic disorders causing migratory thrombophlebitis
Scenario B: Chrissie Williams is a 6-year-old girl, who presents to the pediatric clinic with her mother. The mother tells the nurse practitioner (NP) that Chrissie has a cough that is there "all the time". She coughs up thick mucus and has had four pneumonias this year alone. Chrissie has had frequent chest infections since she was born. Her mother states that she always has "belly pain" and her stools are smelly. A. What does the NP suspect is happening?
A) Chrissie has many of the signs of cystic fibrosis. An overview of CF as a disorder of ventilation and gas exchange is needed. Particular emphasis on the clinical features, of which Chrissie has several, would assist in explaining its course. Pay particular attention to the pathogenesis of this disease and genetic and immunologic components. A review of these concepts may be justified, particularly with the range of infections to which she would be prone and given that this is a chronic lung disease. As well, the diagnostic criteria and testing that is available and treatment options should also be explored. Emphasis should be on the chronicity of illness and how this will impact the client and her family overall.
Scenario C: An 18-year-old woman is admitted to the emergency department with a suspected drug overdose. Her respiratory rate is slow (4-6 breaths/min) and shallow. Arterial blood gases reveal a PCO2 of 80 mm Hg and a PO2 of 60 mm Hg. A. What is the cause of this woman's high PCO2 and low PO2? B. Hypoventilation almost always causes an increase in PCO2. Explain. C. Even though her PO2 increases to 90 mm Hg with institution of oxygen therapy, her PCO2 remains elevated. Explain
A) Hypoventilation due to the decreased respiratory rate of 4 to 6 breaths/minute is causing her high PCO2 and low PO2. B) Hypoventilation almost always causes an increase in PCO2. The rise in PCO2 is directly related to the level of ventilation. If reduction of ventilation is by one half, this will cause doubling of the PCO2. The PCO2 level is a good diagnostic measure for hypoventilation. C) Narcosis is still present. Administration of oxygen therapy only will improve the PO2 in this case, not the patient's ventilatory effort. The patient needs to improve ventilation by reversing the effects of the drug that has been overdosed.
Who receives treatment for TB?
Active TB, contact, at risk, or LTBI
C. Robbie is treated with a systemic corticosteroid and inhaled anticholinergic and beta2-adrenergic agonist and then transferred to the intensive care unit. Explain the action of each of these medications in terms of relieving Robbie's symptoms.
All three medications listed—systemic corticosteroids, β-adrenergics, and anticholinergics—are considered short-acting and quick-relief medications. Systemic corticosteroids may be used for treating the inflammatory reaction associated with the late-phase response. The short-acting β-adrenergic agonists (i.e., albuterol) relax bronchial smooth muscle and provide prompt relief of symptoms, usually within 30 minutes. The anticholinergic drugs (i.e., Ipratropium) block the postganglionic efferent vagal pathways that cause bronchoconstriction. They produce bronchodilation by direct action on the large airways and do not change the composition or viscosity of the bronchial mucus.
Pneumonia in Immunocompromised
An immunocompromised individual has — underlying defects in host defenses What are the risk factors? primary or acquired immunodeficiency states; bone marrow or organ transplantation; solid organ or hematologic cancers; corticosteroid and other immunosuppressant drug therapy Neutropenia causative organisms are — S. aureus, Asperigillus, gram-negative bacilli, Candida Organisms involved when an individual has defects in cellular immunity are often — viruses, fungi, mycobacteria, protozoa (insidious onset)
Why would an individual with the flu be placed on antibiotics?
An individual with COPD or other respiratory risk can develop a secondary bacterial infection
B) Because you hate to miss classes (:->), you decide to go to the student health center to get an antibiotic. After being seen by a health professional, you are told that antibiotics are ineffective against the flu virus, and you are instructed not to attend classes, but instead to go home, take acetaminophen for your fever, go to bed and stay warm, and drink a lot of fluids. Explain the rationale for each of these recommendations.
B) Since influenza is a virus, antibiotics would not be the appropriate treatment. The goals of treatment for influenza are designed to limit the infection to the upper respiratory tract. The symptomatic approach for the treatment of uncomplicated influenza focuses on rest, keeping warm, and drinking large amounts of liquids. Analgesics can also be utilized for symptomatic relief of fever and aching muscles, but it should be remembered that aspirin should be avoided in children because of the risk of Reye syndrome. Antiviral medications may be indicated in some persons. Rest decreases the oxygen requirements of the body and reduces the respiratory rate and the chance of spreading the virus from the upper to lower respiratory tract. Keeping warm helps maintain the respiratory epithelium at a core body temperature (approximately 37°C), thereby inhibiting viral replication, which occurs at sub-core temperatures of approximately 35°C. Drinking large amounts of liquids ensures that the function of the epithelial lining of the respiratory tract is not further compromised by dehydration.
Which chronic obstructive pulmonary disease primarily affects the alveoli? A. asthma B. emphysema C. chronic bronchitis D. bronchiectasis
B. emphysema Rationale: Emphysema results from loss of lung elasticity with abnormal enlargement of the air spaces distal to the terminal bronchioles due to destruction of alveolar walls and capillary beds.
C. Explain why the oxygen flow rate for persons with COPD is normally titrated to maintain the arterial PO2 between 60-65 mm Hg.
Because the ventilatory drive associated with hypoxic stimulation of the peripheral chemoreceptors does not occur until the arterial PO2 has been reduced to about 60 mm Hg or less, increasing the arterial PO2 above 60 mm Hg tends to depress the hypoxic stimulus for ventilation and often leads to hypoventilation and carbon dioxide retention.
The most common site of metastasis of SCLC is __.
Brain
C) Explain why last year's flu shot did not protect you during this year's flu season.
C) The formulation of influenza vaccines must be changed in response to antigenic changes in the influenza virus. The CDC annually updates its recommendations for the composition of the vaccine. The effectiveness of the influenza vaccine in preventing and lessening the effects of influenza infection depends primarily on the age and immunocompetence of the recipient and the match between the virus strains included in the vaccine and those that circulate during the influenza season. When there is a good match, the vaccine is effective in preventing the illness in approximately 70% to 90% of healthy persons younger than 65 years of age.
D) There is concern about the possibility of an influenza pandemic such as the one that occurred during the 1917-1918 season. What is the rationale for this concern? [While COVID-19 is not considered a typical flu - here we are in 2019-2020, and likely longer.]
D) Concern for an influenza pandemic exists within the avian strain research. The normal hosts for avian influenza viruses are birds and occasionally pigs. The virus is highly contagious among avian species and can infect and kill domestic poultry, such as chickens, ducks, and turkeys. Susceptible birds become infected when they have contact with contaminated secretions or feces. The avian strain does not usually cause outbreaks of disease in humans unless a reassortment of the virus genome occurs. This reassortment may occur within an intermediate mammalian host such as a pig, which may produce a virus to which humans may not be immune. Occasionally, outbreaks of human disease occur because of this. Surveillance exists to monitor this risk for a pandemic.
6. Scenario B: Remember Mr. Thompson, who was involved in a motor vehicle accident and suffered a traumatic pneumothorax? A chest tube was inserted, and he was placed on a ventilator. He also sustained a significant head injury that has left him unconscious and in need of ventilator support. Several days later, Mr. Thompson starts to regain consciousness and becomes extremely restless. When the nurse suctions his artificial airway, she observes blood-tinged sputum. He has a low-grade fever and is experiencing tachycardia. D. What does the nurse suspect and why? E. How would a pulmonary embolus be diagnosed? F. Remember about our study of anticoagulant therapy in Chapter 12. What are the nurse's concerns related to this therapy?
D) He may have a pulmonary embolus. The leading cause for pulmonary embolus is deep vein thrombosis (DVT). DVT may result from bed rest and/or trauma, both of which Mr. Thompson experienced. The clot could break loose and obstruct pulmonary blood flow. E) Clinical manifestations, arterial blood gases, D-dimer testing, V/Q scan, pulmonary angiography. F) He is at a greatly increased risk for bleeding. Depending on the type of head injury that he sustained, he could be at an increased risk for a hemorrhagic stroke.
What type of TB may be reactivated if the patient becomes immunocompromised? A) primary B) latent C) miliary D) secondary
D) secondary Rationale: Secondary TB, often referred to as reactivation or reinfection TB, may occur if patients are reexposed to TB bacilli (after a primary infection) or if they become immunocompromised (they are unable to contain the infection).
Which of the following occurs in asthma? A. airway inflammation B. bronchospasm C. decreased ability to clear mucus D. all of the above
D. all of the above
Bronchial Asthma Disease Card
Definition: - chronic disorder of airways causing episodes of airway obstruction due to bronchial smooth muscle hyper-reactivity and airway inflammation Etiology: - exaggerated hypersensitivity response to a variety of stimuli; inflammatory cells damage bronchial epithelium; persistent changes in airway structures with mucus hypersecretion, injury to epithelial cells, smooth muscle hypertrophy, and blood vessel proliferation Manifestations: - episodes of wheezing and feeling of chest tightness to acute immobilizing attacks mild - chest tightness, slight increase in respiratory rate with prolonged expiration, mild wheezing often accompanied by cough severe - use of accessory muscles, distant breath sounds (air trapping), loud wheezing, fatigue, skin moist, anxiety and apprehension, dyspnea; airflow decreases - breath sounds inaudible, wheezing diminishes, ineffective repetitive, hacking cough - onset of respiratory failure Diagnosis: - careful history and physical exam, laboratory studies, pulmonary function tests (FVC, FEV1.0, PEF, tidal volume, expiratory reserve volume, inspiratory reserve volume) Treatment: - control contributing actors (triggers) and institute pharmacologic management - education and prevention of exposure about to irritants and factors increasing symptoms and precipitating exacerbations; annual influenza vaccination - desensitization (extrinsic asthma) - allergen immunotherapy x 3-5 years - quick-relief medications - short-acting B2-agonists, anticholinergic agents that are inhaled as needed; short course systemic corticosteroids for inflammatory reaction associated with late-phase response in moderate to severe asthma - controller medications - long-term medications; inhaled or oral taken daily to achieve and maintain control of persistent symptoms; e.g., inhaled corticosteroids, long-acting bronchodilators, cromolyn and nedocromil, leukotriene pathway inhibitors, theophylline
Influenza Disease Card
Definition: - highly contagious viral infection of the upper respiratory system that may progress to the lungs; most distinguishing feature is the rapid onset of profound malaise Types include - - uncomplicated upper respiratory infection - viral pneumonia - respiratory viral infection followed by bacterial infection Cause: - viruses of Orthomyxoviridae family (types A & B — epidemics; C — mild URI); more contagious than bacterial infection; transmission via droplet nuclei Clinical Manifestations: - abrupt onset of fever/chills, malaise, muscle aching, headache, profuse watery nasal discharge, nonproductive cough, sore throat What types of infections arise? 1) uncomplicated upper respiratory infection, 2) viral pneumonia, 3) respiratory viral infection followed by bacterial infection Diagnosis: - history and physical findings - sudden onset of fever, cough, weakness, myalgias; prevalence in the community and vaccination status of the individual Treatment: - Goal - limit infection to URT; rest, keep warm, increase liquids, analgesic/antipyretic, antitussive - antiviral medication for at-risk individuals initiated with 36-48 hours of onset Complications: - sinusitis, otitis media, bronchitis, bacterial pneumonia
Pleural Effusion Disease Card
Defintion: - abnormal collection of fluid in pleural cavity Etiology: - serous effusion: watery effusion with hydrothorax, caused by increased hydrostatic pressure or decreased osmotic pressure in the blood vessels leading to a shift in fluid out of the blood vessels into the potential space in the pleural cavity, CHF, renal failure, nephrosis, liver failure, malignancy - exudative effusion: proteins and WBCs, caused by bacterial pneumonia, viral infection, pulmonary infarction, malignancy - chylothorax effusion: glucose, proteins, leukocytes, dead cells and tissue debris, caused by effusion of lymph - hemothorax effusion: blood, caused by trauma, cancer or surgery Clinical Manifestations: - dullness/flatness to percussion, diminished breath sounds, hypoxemia, decrease in lung expansion; empyema manifests with fever and increased WBC Diagnosis: - CXR, chest ultrasonography, CT, thoracentesis to determine cause and treat Treatment: - thoracentesis to remove intrapleural space fluid and pressure and allow for lung re-expansion, chest tube drainage for continued effusion, palliation for effusion from malignancy - injection of sclerosing agent
Pathological fungi induce what type of hypersensitivity response?
Delay cell-mediated hypersensitivity response in which cellular immunity is mediated by antigen-specific T lymphocytes and cytokine-activated macrophages that assume fungicidal properties.
The following are some known causes of pulmonary hypertension:
Diet drug "fen-phen" - dexfenfluramine and phentermine has been taken off the market, former fen-phen users have a 23-fold increased risk of developing pulmonary hypertension - possibly years later Liver disease, rheumatic disease, lung conditions - pulmonary hypertension also can occur as a result of other medical conditions, such as chronic liver disease and liver cirrhosis, rheumatic disorders like scleroderma or systemic lupus erythematosus, and lung conditions, including tumors, COPD, fibrosis Certain heart diseases - aortic valve disease, left heart failure, mitral valve disease, and congenital heart disease Thromboembolic disease - blood clot in a large pulmonary artery Low-oxygen conditions - high altitude living, obesity, and sleep apnea Genetics - inherited in a small number of cases Idiopathic - unknown cause
Lobar Pneumonia
Distribution: All of 1 or 2 lobes Main Causative Pathogen: Streptococcus pneumoniae Pathophysiology: Inflammation of alveolar wall and leakage of cells, fibrin, and fluid into alveoli causing consolidation; pleura may be inflamed Onset: Sudden, acute Manifestations: High fever and chills, productive cough with rusty sputum, rales progressing to the absence of breath sounds in affected lobe(s)
Interstitial Pneumonia (Atypical)
Distribution: Alveolar septum and interstitium Main Causative Pathogen: Influenza virus, Mycoplasma Pathophysiology: Interstitial inflammation around alveoli; necrosis of the bronchial epithelium Onset: Variable Manifestations: Variable fever, headache, aching muscles, nonproductive hacking cough
Bronchopneumonia
Distribution: Scattered small patches in alveoli involving >1 lobe Main Causative Pathogen: Multiple bacteria Pathophysiology: Inflammation and purulent exudate in alveoli often arising from prior pooled secretions or irritation Onset: Insidious Manifestations: Mild fever, productive cough with yellow-green sputum, dyspnea
For which viruses is a 2-year-old most at risk? A) rhinoviruses B) parainfluenza viruses C) respiratory syncytial virus (RSV) D) A, B, and C E) B and C
E) B and C Rationale: Slightly older children (>5 years of age) are at risk for rhinoviral infections. Children under the age of 3 are at risk of infection from both parainfluenza viruses and RSV.
How can atelectasis be avoided after surgery?
Educate the patient to cough and deep breathe (using bedside spirometer), change position frequently, maintain adequate hydration, and start early ambulation.
Secondary pulmonary hypertension may be the result of ____. A) sarcoidosis B) COPD C) heart failure D) sleep apnea E) B only F) B, C, and D
F) B, C, and D
A person with asymptomatic latent TB can transmit the organism.
False
An individual with a positive tuberculin skin test has active TB.
False
Bacteria are the most frequent cause of respiratory tract infections. True or False?
False
Primary TB always has an insidious onset of fever, weight loss, fatigue & night sweats.
False
Primary tuberculosis represents reinfection from either inhaled droplet nuclei or reactivation of a previously healed primary lesion. True or False?
False
Persons with emphysema are often labeled as "blue bloaters" due to the chronic hypoxemia and eventual right-sided heart failure with peripheral edema. True or False?
False Rationale: Blue-bloater is a term describing individuals with chronic bronchitis due to cyanosis and fluid retention.
A patient suffering from ARDS will not necessarily be hypoxemic. True or False?
False Review the diagram in 11.7 on the mechanisms of lung injury in ARDS. In ARDS, the alveoli are filled with exudate, decreasing the available surface area for gas exchange. If gas exchange decreases, poorly oxygenated or unoxygenated blood is sent to the tissues - resulting in hypoxemia
SCLC is primarily treated with resection followed by adjunctive irradiation.
False Because it is highly malignant & metastasizes early and widely, it is rarely resectable. It is usually treated with chemotherapy with or without radiation therapy
Hypercapnia refers to an abnormal increase in oxygen level. True or False?
False Rationale: Hypercapnia is an increase in carbon dioxide levels.
Pleural, musculoskeletal, and myocardial pain are similar in description and almost impossible to differentiate. True or False?
False: Rationale: Pleural pain is sharp and accompanied by shortness of breath - typically unilateral with abrupt onset abd associated with somatic pain fibers. Musculoskeletal pain is caused by frequent, forceful coughing and is bilateral, located in the inferior portions of the rib cage. Pain from irritation of the bronchi is substernal and dull. Myocardial pain is located in the substernal area and not affected by respiratory movement.
Scenario A: Lance Coughlin is a 60-year-old male, who has been having difficulty catching his breath for about 2 months. He finds he gets short of breath even when resting. He has a wet cough, has been coughing up blood, and is hoarse. He states that he has had chest pain off and on, but now it has become more severe. He describes it as central chest pain. The client was treated for a basal cell carcinoma of his upper lip 12 months ago, and he has been a heavy smoker for 40 years. A. What would you consider in this case?
Given tMr. Coughlin's history of smoking, skin cancer, and presenting symptoms, it is highly likely that he has lung cancer. The close correlation of smoking, gender, central chest pain, and recent skin cancer of the lip fits with squamous cell carcinoma. Consider several prior learned concepts:Cellular response to stress and injury; cell cycle and malignancy as it relates to neoplasia; environmental and host factors of cancer; and stress. Mr. Coughlin's symptoms must be considered for potential complications (i.e., hoarseness as its relationship to the laryngeal nerve, blood flow to that region, and superior vena cava syndrome or central chest pain and pleural effusion). The concept of metastatic spread via the lymph system needs to be acknowledged
_____ is caused by a dimorphic fungus and is one of the most common fungal infections in the U.S. This respiratory infection produces pulmonary manifestatons similar to _____.
Histoplasmosis; tuberculosis
Define the following: hypoxia, hypoxemia, hypercapnia, and atelectasis.
Hypoxia - decreased oxygen in tissues Hypoxemia - decreased PaO2 in the blood; may be due to hypoventilation; impaired diffusion of gases; inadequate pulmonary circulation, ventilation/perfusion mismatch Hypercapnia - increased arterial blood CO2; may be due to hypoventilation or ventilation/perfusion mismatch Atelectasis - incomplete lung expansion due to airway obstruction, decreased pulmonary surfactant or lung compression; manifestations include tachypnea, tachycardia, dyspnea, cyanosis, hypoxemia, decreased chest expansion, absent breath sounds, intercostal retractions
Fungal infections are treated symptomatically, but individuals, who are ___ or have ___, are treated with antifungal therapy.
Immunocompromised; progressive disease
Influenza A
Influenza A is categorized into subtypes based on 2 glycoproteins that stud the lipid envelope: - hemagglutinin (H) - neuraminidase (N) - there are 16 different variants of hemagglutinin and 9 variants of neuraminidase - hemagglutinin allows the virus to anchor to the surface of epithelial cells in the respiratory tract, while neuraminidase allows for digestion of host secretion and release of viral particles from host cells - these viruses mutate constantly, preventing effective immune defense for prolonged periods of time - new subtypes develop resulting in a population that is not protected leading to epidemics and pandemics
______ produces inflammatory and fibrotic changes in interstitium or interalveolar septa and affects collagen and elastic connective tissue.
Interstitial lung disease
_____ involves IgE antibodies and triggers can include respiratory tract infection, exercise, hyperventilation, and cold air.
Intrinsic (nonatopic) asthma
HAI pneumonia risk factors include ___.
Intubation & mechanical ventilation
Tuberculosis is an infectious disease caused by _______, a rod-shaped aerobic bacterium that is resistant to destruction.
Mycobacterium tuberculosis
A person can be immunocompromised due to leukemia, chemotherapy, and bone marrow depression. What causes the risk?
Neutropenia
Antiviral medications should be routinely given to individuals developing the flu.
No
Ruth has diabetes and hypertension. Since her congestion has not cleared with the nasal spray, she plans to start a nasal decongestant. Is this a good idea?
No
Ruth wants her doctor to order her an antibiotic to help "get rid of her cold". The doctor will likely order an antibiotic for the specific virus.
No
B. His arterial PO2 and O2 saturation indicated that he is a candidate for continuous low-flow oxygen. Explain the benefits of this treatment in terms of his activity tolerance, blood pressure, and red blood cell count.
Oxygen therapy is prescribed for selected persons with significant hypoxemia (arterial PO2 <55mm Hg). Administration of continuous low-flow oxygen (1 to 2 L/min) to maintain arterial PO2 levels between 55 and 65 decreases dyspnea and pulmonary hypertension and improves neuropsychological function and activity tolerance.
difference between arterial PO2 and the fraction of inspired oxygen
PF ratio
S. pneumoniae can often be prevented by ___.
Polysaccharide pneumococcal vaccine to at risk individuals
What is the difference between primary tuberculosis and reactivated tuberculosis?
Primary tuberculosis occurs in previously unexposed/unsensitized individuals; inhalation of droplet nuclei containing tubercle bacillus; T lymphocytes and macrophages wall off the organism in granulomas. Reactivated tuberculosis is a reininfection from inhaled droplet nuclei.
Scenario B: Back to Mr. Thompson, who received a head and chest injury in a motor vehicle accident. A chest tube was inserted to treat the traumatic pneumothorax and he was placed on a ventilator due to the head injury that left him unconscious. He developed a pulmonary embolus and was treated. The next day, the nurse notices that Mr Thompson has marked hypoxemia, which is not responding to increased levels of oxygen. A chest x-ray is obtained, which reveals diffuse bilateral infiltrates. He is diagnosed with ALI/ARDS. A. What is the pathophysiology associated with ALI/ARDS?
Pulmonary injury → accumulation of neutrophils in microcirculation → activation and migration across alveolar epithelial surfaces releasing proteases, cytokines, and reactive oxygen species → increased alveolar and epithelial cell permeability → damage to type I and II alveolar cells → edema, hyaline membrane formation, loss of surfactant → decreased pulmonary compliance → impaired gas exchange.
A distinguishing feature of influenza compared to other URIs is ___.
Rapid onset of profound malaise
____ refers to inflammation of the nasal passages, and sinusitis as inflammation of the _____ sinuses. The lower _____ content in the sinuses facilitates the growth of organisms, impairs local defenses, and alters the function of immune cells.
Rhinitis; paranasal; oxygen
Which virus is the most common cause of a cold occurring in people aged 5-40 years and in the early fall and late spring?
Rhinovirus
The most common viruses are...
Rhinovirus: - 10-40% of Colds - Age Affected: 5-40 years - Active Period: Early fall, late spring, summer Coronavirus: - 20% of Colds - Age Affected: Most people will have 1 or more infections during lifetime - Active Period: Winter and early spring Parainfluenza (HPIV) / respiratory syncytial virus: - 20% of Colds - Age Affected: <3 years - can lead to pneumonia - HPIV has 4 subtypes - may occur spring, early summer, or late fall RSV - late fall, winter, early spring Adenovirus: - Infrequent - Age Affected: Infants and immunocompromised - can lead to pneumonia - Active Period: Late winter, spring, early summer
What is the most common organism causing CAP pneumonia?
S. Pneumoniae
Pneumococcal pneumonia is caused by ___.
S. pneumoniae
What are the methods for classifying pneumonias?
Setting: community or hospital Agent: typical (bacteria), atypical (viral & mycoplasma infections) Distribution: lobar (consolidation of part or all of lung lobe), bronchopneumonia (patchy consolidation involving more than 1 lobe)
Fungal respiratory infections are diagnosed via ___ and/or direct visualization of organism from tissue specimens or __.
Skin testing; sputum culture
The three types of NSCLC are __.
Squamous cell, adenocarcinoma, large cell
Non-small cell lung cancer is staged at the time of diagnosis based on the tumor size-node involvement-metastases (TNM) classification:
Stage I - Cancer located only in the lungs and has not spread to any lymph nodes Stage II Cancer located in the lung and nearby lymph nodes Stage III Cancer found in lung and in lymph nodes in the middle of the chest, also described as locally advanced disease. Stage III subtypes: Stage IIIA - spread only to lymph nodes on the same side of the chest where the cancer started Stage IIIB - spread to the lymph nodes on the opposite side of the chest, or above the collarbone Stage IV This is the most advanced stage of lung cancer, and is also described as advanced disease. The cancer has spread to both lungs, to fluid in the area around the lungs, or to another part of the body, such as the liver or other organs.
NSCLC is classified by cell type and staged by the __ system.
TNM
B. Based on those conclusions, what would the NP consider for Chrissie and her family?
The NP would have to consider the impact that such a diagnosis would have on the family unit, and perhaps further testing on additional family members is needed. Regular family meetings would probably be a good approach to ensure that all were informed. As with an illness such as CF, it would entail a link with many specialists who would also be caring for the client: geneticist, gastroenterologist, pulmonologist, respiratory therapist, etc. A team approach would have to be taken from the very beginning not only for the medical aspects but for the psychological stressors as well. Many other disciplines would be involved as well as community resources and groups (school and CF foundations, to name a few). Financial resources would also have to be addressed, as costs for treatment options could be high.
What are the diagnostic tests?
There is no readily available screening test for lung cancer, although research continues to identify means to diagnose tumors before metastasis and spread - Specialized helical CT scans and MRI are more effective in early diagnosis than chest x-rays, which demonstrate later lesions and complications, like atelectasis or pleural effusion - Bronchoscopy provides secretions containing malignant cells from central lesions for definitive diagnosis, and biopsy may be required for less accessible lesions. Mediastinoscopy is also useful to check lymph nodes and examine the inside of the upper chest in front of the lungs - Cytological studies of sputum or bronchial washings - Percutaneous needle biopsy - Scalene lymph node (supraclavicular) biopsy - Bone scans are used to detect metastasis - useful in the staging process - Positron emission tomography (PET) identifies metastatic lesions in the mediastinum or distant sites; e.g., brain metastasis - Pulmonary function tests can clarify the effects of the tumor on airflow
Cystic fibrosis is manifested by pancreatic exocrine deficiency and a noted increase in levels of sodium chloride in sweat. True or False?
True
Extrinsic or atopic asthma is typically initiated by a type 1 hypersensitivity reaction induced by exposure to an antigen or allergen. True or False?
True
Influenza is a viral infection that can affect the upper and lower respiratory tracts and is transmitted by aerosol or direct contact. True or False?
True
Legionnaire disease can be transmitted contaminated water that is aerosolized and inhaled/aspirated.
True
The abrupt onset of primary tuberculosis begins with high fever, pleuritis, and lymphadenitis.
True
Typical pneumonias result from infection by bacteria. True or False?
True
Both hypercapnia and hypoxemia will lead to respiratory failure if untreated. True or False?
True Rationale: In both hypercapnia with Pco2 >50 mmHg, tissues accumulate carbon dioxide; in hypoxemia with Po2 <60 mmHg, less oxygen is delivered to the tissues. In both cases gas exchange is impaired, and respiratory failure will result unless the conditions are corrected - with oxygen, mechanical ventilation, etc.
____ are the most frequent cause of respiratory tract infections. These types of infections can damage ____ epithelium, _____ airways, and lead to ______ infections.
Viruses; bronchial; obstruct; secondary
false-negative tuberculin skin test
anergy
_____ is the most frequent admitting diagnosis in children's hospitals and is a leading cause of chronic illness in children
asthma
Persons who are immunocompromised with defects in humoral immunity usually develop ___ pneumonia.
bacterial
Tuberculosis is a highly destructive disease because the tubercle bacillus activates a tissue hypersensitivity to the tubercular antigens. What does the destructive nature of tuberculosis cause in a previously unexposed immunocompetent person?
caseating necrosis and cavitation
results from an excessive concentration of reduced hemoglobin
cyanosis
Antibiotic with sensitivity for L. pneumophila should be initiated __.
early and to anyone with severe CAP
A ______ is acquired by inhalation when spores are released in dust or dirt from an infected area; e.g., soil.
fungal infection
What are common diagnostic tests?
- Spirometry - pulmonary function testing (PFT) - tests pulmonary volumes (volumes inspired and expired and airflow times) - Arterial blood gases (ABG) - check oxygen, carbon dioxide, and bicarbonate levels and serum pH - Pulse oximetry - O2 saturation - Exercise tolerance testing - chronic pulmonary disease for diagnosis and patient progress monitoring - Radiography - evaluation of tumor or infections (pneumonia, TB) - Bronchoscopy - biopsy or checking for the site of lesion or bleeding - Culture and sensitivity tests on exudates from upper airways or sputum - identify pathogens
NSCLC treatment:
- Surgery - lobectomy, pneumonectomy, or segmental resection - Radiation - main treatment modality; may be combined with chemotherapy - Frequently palliative care - Chemotherapy - multidrug therapy
The diagnosis of fungal pneumonia relies on...
- a combination of clinical, radiologic, and microbiological factors
Stridor
- a high-pitched crowing noise and usually indicates upper airway obstruction
Large or Multiple Pulmonary Embolisms
- a large pulmonary embolism or multiple emboli can cause overloading of the pulmonary circulation - when a certain area of the pulmonary arterial tree (usually more than half) is occluded by clots, pressure in the pulmonary artery rises - the sudden onset of pulmonary hypertension often does not give the heart time to adapt and rapidly leads to right ventricular failure - such an event, occasionally referred to as acute cor pulmonale, can be fatal - it may reverse itself when pulmonary emboli are treated by surgery, thrombolytic therapy, or anticoagulant therapy - patients with acute cor pulmonale are short of breath, may be in shock, and show signs of right ventricular failure - massive pulmonary embolism occluding the main pulmonary artery or the two principal branches causes death, usually instantly and without warning - it is the prevention of this complication that has placed so much emphasis on signs of any disturbance of the venous circulation and prophylactic anticoagulation therapy
Antigenic drift
- a mechanism for variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites - this results in a new strain of virus particles that cannot be inhibited as effectively by the antibodies that were originally targeted against previous strains, making it easier for the virus to spread throughout a partially immune population - antigenic drift occurs in both influenza A and B viruses - Antigenic shift is the process by which two or more different strains of virus, or strains of two or more different viruses, combine to form a new subtype having a mixture on the surface antigens of the two or more original strains
Sneezing
- a reflex response to irritation in the upper respiratory tract and assists in removing an irritant - it is associated with inflammation or foreign material in the nasal passages
The common cold is predominantly mild and self-limited and characterized by...
- a runny nose - nasal congestion - sneezing - cough - malaise - sore throat - fever
What is the difference between ALI and ARDS?
- acute lung injury (ALI) is a less severe form of acute respiratory distress syndrome (ARDS) - the differentiating factor is the extent of hypoxemia, which is determined by the ratio of the partial pressure of oxygen in the arterial blood (Po2) to the fraction of inspired oxygen (FIO2)
How does respiratory failure occur?
- acute respiratory failure is a life-threatening impairment of oxygenation, CO2 elimination, or both - respiratory failure may occur because of impaired gas exchange, decreased ventilation, or both - common manifestations include dyspnea, use of accessory muscles of respiration, tachypnea, tachycardia, diaphoresis, cyanosis, altered consciousness, and, without treatment, eventually respiratory arrest and death - diagnosis is clinical, supplemented by ABGs and chest x-ray - treatment is usually in an ICU and involves correction of the underlying cause, supplemental O2, control of secretions, and ventilatory assistance, if needed
Advanced Emphysema
- advanced emphysema and significant loss of tissue results in adjacent damage causing alveoli to coalesce and form large air spaces - the tissue and pleural membrane surround large blebs near the surface of the lung - these may rupture and cause a pneumothorax - hypercapnia becomes marked and hypoxic drive for inspiration develops as the individual's respiratory control adapts to the chronic elevation of carbon dioxide levels and hypoxia becomes the driving force for respiration
Tuberculosis after necrosis
- after necrosis, the tubercles change by fibrosing and calcifying - if the immune system is effective in walling off the bacteria, the disease may be arrested or rendered inactive for months to years - during this time, the person is usually asymptomatic - the antibodies that are produced circulate in the blood for the remainder of the infected person's life - that's the basis for the positive reaction to a TB skin test - if the disease is not arrested and the immune response is inadequate, the person will become symptomatic with progressive primary tuberculosis with more destruction of lung tissue in multiple sites within the lung
alveolar ducts
- air in the bronchioles then flows into the alveolar ducts and alveoli - the alveoli are formed by a single layer of simple squamous epithelial tissue, which promotes the diffusion of gases into the blood, the end-point for inspired air - the respiratory membrane is the combined alveolar and capillary wall, which forms a very thin membrane through which gas exchange takes place
How do inspiration and expiration occur?
- airflow during inspiration and expiration depends on a pressure gradient, with air always moving from a high-pressure area to a low-pressure area - one way only - if atmospheric pressure is higher than air pressure inside the lungs, air will move from the atmosphere into the lungs - inspiration - for expiration to occur, pressure must be higher in the lungs than in the atmosphere - these pressure changes in the lungs result from alterations in the size of the thoracic cavity - as the size of the thoracic cavity decreases, the pressure inside the cavity increases - Boyle's law
All types of asthma exhibit...
- all types of asthma exhibit the same pathophysiologic changes related to inflammation during an acute attack - the bronchi and bronchioles respond to the stimuli with three changes - inflammation of the mucosa with edema, contraction of smooth muscle (bronchoconstriction), and increased secretion of thick mucus in the passages - these changes create partially or totally obstructed airways and interfere with airflow and oxygen supply
Open Pneumothorax
- an open pneumothorax results as air enters the pleural cavity through the wound with inhalation and leaves upon exhalation - the lung reinflates somewhat
The rate and depth of breathing set by the medullary center can be modified by a number of factors:
- any depression of central nervous system activity; e.g., by drugs (such as morphine), can lead to slow, shallow breathing - other factors include activity of the hypothalamus (e.g., response to emotions); or the stretch receptors in the lungs (i.e., the Hering-Breuer reflex), which prevents excessive lung expansion; or voluntary control; e.g., required when singing
Antibacterial agents...
- are not effective and there are no antiviral agents available to treat these infections - the development of vaccines for the common cold has been difficult because of antigenic variability of the common cold virus and the indistinguishable and multiplicity of other viruses
Oxygen Diffusion
- as oxygen diffuses out of the blood into the interstitial fluid and the cells, hemoglobin releases oxygen to replace it, so dissolved oxygen is always available in the plasma and ready to diffuse into the cells - the rate at which hemoglobin binds or releases oxygen depends on the partial pressure of dissolved oxygen (Po2), the partial pressure of dissolved carbon dioxide (Pco2), the temperature, and plasma pH - normally 25% of the bound oxygen is released to the cells for metabolism during an erythrocyte's trip through the systemic circulation, leaving 75% of the hemoglobin in the venous blood still saturated with oxygen - a good safety margin that is available to meet increased cell demands
Symptoms and diagnosis associated with idiopathic pulmonary fibrosis:
- associated systemic symptoms that can occur but are not common in idiopathic pulmonary fibrosis include the following: weight loss, low-grade fever, fatigue, arthralgias, and myalgias - the diagnosis is more one of ruling out other causes of lung disease - imaging studies include high-resolution computed tomography scanning, chest x-ray (with nonspecific abnormal findings), transthoracic echocardiography demonstrating pulmonary hypertension, bronchoscopy also rules out other causes, and surgical lung biopsy (open or video-assisted thoracoscopic surgery) can distinguish interstitial pneumonia from other idiopathic interstitial pneumonias
Describe lower respiratory tract function
- at the lower end of the trachea, inhaled air proceeds into the right or left primary bronchus - the right bronchus is larger and straighter - so it is the more likely destination for any aspirated material - the point at which the bronchus enters the lung is the hilum - each major or primary bronchus then branches into many secondary bronchi and then into bronchioles forming an inverted bronchial "tree" - as the bronchi divide into bronchioles, supportive cartilage is no longer present - the smooth muscle contracts or relaxes to adjust for the diameter of the bronchioles - bronchodilation results when sympathetic stimulation relaxes the smooth muscle - dilating or enlarging the bronchioles - many elastic fibers are present in the lung tissue, enabling the expansion and recoil of the lungs during ventilation - the respiratory mucosa thins and changes from pseudostratified columnar to simple columnar and then to simple cuboidal epithelium in the terminal respiratory bronchioles
How is atelectasis caused?
- atelectasis is the non-aeration or collapse of a lung or part of a lung leading to decreased gas exchange and hypoxia - it occurs as a complication of several primary conditions - treatment depends on removing the underlying cause, whether obstruction or compression, before re-inflating the lung - when the alveoli become airless, they shrivel up from the natural elasticity of the tissues - this process also interferes with blood flow through the lung - both ventilation and perfusion are altered, affecting oxygen diffusion - unless a very large proportion of the lung is affected, the increased respiratory rate can control carbon dioxide levels - because it diffuses easily - if the lungs aren't reinflated quickly, the lung tissue can become necrotic and infected - permanent lung damage results
Hemoglobin
- because oxygen is poorly soluble in plasma, the erythrocyte along with the hemoglobin molecule carries 95-98% of oxygen to the tissues - hemoglobin is made up of 2 pairs of polypeptide chains (alpha and beta) and each chain carries a heme unit, which surrounds an atom of iron and binds oxygen, and a globin, which is a protein - structural genes on 5 gene loci control the globin chain
Breath Sounds
- breath sounds are auscultated and may be abnormal or absent - rales are light bubbly or crackling sounds associated with serous secretions - rhonchi are deeper and harsher sounds resulting from thicker mucus - the absence of breath sounds indicates nonaeration or collapse of a lung - atelectasis
Breathing Patterns
- breathing patterns and characteristics can also indicate disease - normal respiration (eupnea) is 10-18 inspirations per minute with a regular and effortless pattern - Kussmaul respirations (air hunger) are deep, rapid and typical of acidosis - or can just follow strenuous exercise - labored or prolonged inspiration or expiration is associated with airway obstruction - wheezing, or whistling sound, indicates an obstruction in the small airways
Bronchial asthma in children:
- bronchial asthma in children is an IgE-related reaction occurring in bronchiolitis, severe RSV infection, exposure to environmental allergens (pet dander, dust mite antigens, cockroach allergens) and exposure to tobacco smoke - it is more prevalent among African-American children, and 80% of children with asthma are symptomatic before age 6 - it also exhibits with nocturnal asthma due to airway patency decreases at night - the manifestations include rhinorrhea, irritability, tight nonproductive cough, wheezing, tachypnea and dyspnea with prolonged expiration, use of accessory muscles and increasing severity with cyanosis, hyperinflation of the chest and tachycardia - diagnosis and treatment are similar to adult asthma - medication delivery systems for infants and small children include nebulizers with facemasks and spacers or holding chambers for use with metered dose inhalers
What is another type of COPD?
- bronchiectasis is usually a secondary problem that develops in individuals with conditions such as cystic fibrosis or COPD - some cases result from childhood infection, aspiration of foreign bodies, or a congenital weakness in the bronchial wall - depending on the cause, the condition may be localized in one lobe, or more diffuse - involving both lungs
Hypoxemia
- changes in arterial blood gases (ABGs) may demonstrate hypoxemia (inadequate oxygen in the arterial blood - Pao2) - hypoxia is inadequate oxygen supply to the cells - from too little RBCs or hemoglobin, circulatory impairment, excessive release of oxygen from RBCs, impaired respiratory function, or carbon monoxide poisoning
Effects of Emphysema
- changes in the lung tissue have many effects on lung function with breakdown of the alveolar wall, fibrosis and thickening of the bronchial walls, and progressive difficulty with expiration - difficulty with expiration leads to air trapping and increased residual volume, overinflation of the lungs, fixation of the ribs in an inspiratory position, and increased anterior-posterior diameter of the thorax with flattening of diaphragm
Chronic asthma
- chronic asthma and chronic obstructive lung disease may develop from irreversible damage in the lungs when frequent and severe acute asthmatic attacks form a pattern - the bronchial walls become thickened and fibrous tissue, resulting from the frequent infections that follow attacks, develops into areas of atelectasis - because it is impossible to remove all the tiny mucous plugs in the small passages, complications are common following episodes of asthma
Chronic bronchitis
- chronic bronchitis is differentiated by significant changes in the bronchi resulting from constant irritation from smoking or exposure to industrial pollution - the effects are irreversible and progressive - inflammation and obstruction, repeated infections, and chronic coughing characterize bronchitis - the mucosa become inflamed and swollen followed by hypertrophy and hyperplasia of the mucous glands - the number of goblet cells is increased, and there is decreased ciliated epithelium
What causes chronic obstructive pulmonary disease?
- chronic obstructive pulmonary disease causes irreversible and progressive damage to the lungs - eventually, respiratory failure may result due to hypoxia or hypercapnia - in many individuals, COPD leads to the development of cor pulmonale - right-sided congestive heart failure - COPD is a debilitating condition that affects the individual's ability to work and function independently - examples of these disorders are emphysema and chronic bronchitis
What is the etiology of lung cancers?
- cigarette smoking is the major factor in lung cancer development - "Second-hand smoke" in the environment has been implicated in a significant number of cases - the risk of developing cancer is higher in persons who begin smoking early, persist for many years, and are considered heavy smokers (i.e., >1 pack/day) - not all smokers develop lung cancer, and therefore, there is probably a genetic factor involved that also influences the cellular changes - also, tumors may develop in a person with chronic obstructive pulmonary disease (COPD) - of course, this condition is also associated with smoking - occupational or industrial exposure to carcinogens, such as silica, vinyl chloride, or asbestos is the other major cause of lung cancer, and the risk is greatly increased if a second factor such as cigarette smoking is also present in an occupationally exposed person
Clubbed Fingers
- clubbed fingers, and sometimes toes, result from chronic hypoxia associated with respiratory or cardiovascular disease - it is a painless, firm fibrotic enlargement at the end of the fingers or toes
Epidemiologic - site of occurrence
- community-acquired pneumonia - an infection that begins outside the hospital or diagnosed within 48 hours after hospital admission of a person who has not resided in a long-term care facility for 14 or more days prior to hospital admission - hospital-acquired pneumonia - nosocomial lower respiratory tract infection not present or incubating on admission to the hospital - 48 hours or more after admission
Cyanosis
- cyanosis is a bluish coloring of the skin and mucous membranes that results from large amounts of unoxygenated hemoglobin in the blood - it may develop in peripheral areas as a result of exertion or be more generalized
Cyanosis
- cyanosis of the skin and mucous membranes is caused by excessive concentration of reduced or deoxygenated hemoglobin in the small blood vessels - it's mostly observed in the lips, nail beds, ears, and cheeks - central cyanosis is evident in the tongue and lips. It is caused by an increased amounts of deoxygenated hemoglobin in the arterial blood - peripheral cyanosis occurs in the extremities and the tip of the nose or ears where there is slowing of blood flow to an area of the body with increased extraction of oxygen from the blood
How does cystic fibrosis contribute to COPD?
- cystic fibrosis (CF) is a genetic disorder in which there are several mutations to the CFTR gene that relate to a protein involved in chloride ion transport in the cell membrane - the mutated CFTR gene for cystic fibrosis is located on the seventh chromosome, and the disease is transmitted as an autosomal recessive disorder - this defect in the exocrine glands causes abnormally thick secretions in the lungs - tenacious mucus. CF mainly affects the lungs, sweat glands, pancreas, liver, intestines, sinuses, and sex organs - the primary effects of CF are seen in the lungs and the pancreas where the sticky mucus obstructs the passages; other tissues are affected less frequently - the severity of the effects varies among individuals
Diagnosis of ARDS
- diagnosis involves chest x-ray and ABGs. Hypoxemia is usually first recognized using pulse oximetry - hypoxemia can occur before changes are seen on x-ray
Diagnostics for Sarcoidosis
- diagnostic imaging studies include chest x-rays, chest computed tomography, high-resolution CT scan, and gallium scans - diagnosis requires endobronchial biopsy via bronchoscopy - it manifests in the lungs as noncaseating granulomas mostly in the lungs and intrathoracic lymph nodes that stain negative for fungus and mycobacteria - it is staged based on a scale from 0-IV - normal chest x-ray findings to fibrosis
Dyspnea
- dyspnea is a subjective feeling of discomfort that occurs when a person feels unable to inhale enough air - as in breathlessness or shortness of breath - severe dyspnea can be accompanied by flaring of nostrils, use of accessory respiratory muscles, or retraction of the muscles between or above the ribs - orthopnea is dyspnea that occurs when a person is lying down - e.g., in pulmonary congestion more blood pools in the lungs when the person lies down and the abdominal contents push upward against the lungs - paroxysmal nocturnal dyspnea is a sudden acute type of dyspnea common in people with left-sided CHF
Partial Pressures
- each gas in a mixture moves or diffuses according to its own partial pressure gradient and independent of other gases - Dalton's law - for example, oxygen diffuses from alveolar air, an area with a high concentration of oxygen, to the blood in the pulmonary capillary, which has a low concentration of oxygen, until the concentrations become equal - carbon dioxide diffuses out of the pulmonary capillary into the alveolar air depending on its relative concentrations - atmospheric air contains oxygen, carbon dioxide, nitrogen, and water - because the air is not totally expired from the alveoli during expiration and has been humidified during passage into the lungs, alveolar air has different concentrations of gases than either atmospheric air or blood - the residual air in the alveoli allows continuous gas exchange between expiration and inspiration because of the continuous flow of blood through the pulmonary circulation
What causes pleuritis (pleurisy)?
- each lung is covered by its own double-walled sac - the pleural membrane - the visceral pleura is attached to the outer surface of the lung and then doubles back to form the parietal pleura, which lines the inside of the thoracic cavity, adhering to the chest wall and the diaphragm - the visceral pleura lies closely against the parietal pleura, separated only by very small amounts of fluid in the pleural cavity or space, which is considered a potential space - the slightly negative pressure (less than atmospheric pressure) in the pleural cavity also assists in holding the pleura in close approximation and promoting lung expansion - the pleural fluid provides lubrication during respiratory movements and force that provides cohesion between the two pleural layers during inspiration - diseases of the pleura and chest can be caused by infection, trauma, or other diseases - pain and shortness of breath are the common symptoms - the severity of the disorders ranges from mild to severe, depending on the cause, the individual's age, medical history, and other complicating factors
Airspace filling in ARDS may result from:
- elevated alveolar capillary hydrostatic pressure (e.g., left ventricular failure or hypervolemia - increased alveolar capillary permeability (e.g., any condition predisposing to acute respiratory distress syndrome (ARDS)) - blood (e.g., diffuse alveolar hemorrhage) or inflammatory exudates (e.g., pneumonia or other inflammatory lung conditions)
Endemic Fungal Pathogens
- endemic fungal pathogens (e.g., Histoplasma capsulatum, Coccidioides immitis , Blastomyces dermatitidis ) cause infection in both healthy hosts and the immunocompromised - opportunistic organisms - like Candida or Aspergillus - may cause pneumonia in people with congenital or acquired defects in their immune defenses
The thorax and lungs must _____ before more air can enter the lungs - it is not the air entering the lungs that makes them expand.
- expand - Inspiration requires physical effort and cellular energy - on the other hand, quiet expiration is a passive process and does not require cellular energy
Extrinsic Asthma
- extrinsic asthma involves acute episodes triggered by a type I hypersensitivity reaction to an inhaled antigen - frequently, there is a familial history of other allergic conditions such as allergic rhinitis or eczema, and onset commonly occurs in children - some individuals may no longer be subject to attacks after adolescence
Flu vs. Common Cold
- flu differs from the common cold in that it usually has a sudden, acute onset with fever, marked fatigue, and aching pains in the body - it may also cause viral pneumonia - similarly to the common cold, a mild case of influenza can be complicated by a secondary bacterial pneumonia - during flu epidemics, most deaths result from pneumonia - the incubation period for the virus is 1-4 days with an average of 2 days, but the individual can transmit the virus during the 24 hours before symptoms appear and up to 5 days after
Forced inspiration or expiration
- forced inspiration or expiration requires additional energy and muscular activity - during forced inspiration the sternocleidomastoid, scalene, pectoralis minor, and serratus muscles contract to increase the elevation of the ribs and sternum - forceful expiration requires abdominal muscles to contract to increase upward pressure on the diaphragm, while the intercostal muscles contract to pull the ribs and sternum down and inward
Fungal Pneumonia
- fungal pneumonia is an infectious process in the lungs caused by one or more endemic or opportunistic fungi - fungal infection occurs following the inhalation of spores or by reactivation of a latent infection - sounds very similar to TB - just a different organism - hematogenous dissemination frequently occurs, especially in an immunocompromised host
What is gas exchange?
- gas exchange is external respiration - the flow of gases between the alveolar air and the blood in the pulmonary circulation - diffusion of oxygen and carbon dioxide depends on the relative concentration, or partial pressures of the gases - the movement of each gas always occurs from a high-pressure area to a low-pressure area - the concentration of a gas such as oxygen in a mixture is the partial pressure of the gas - Po2 - when the measurement refers specifically to the partial pressure of oxygen in arterial blood, it is expressed as Pao2
What are the mechanisms of gas exchange?
- gas exchange occurs both in the lungs and at the tissue level throughout the body - in the lungs, carbon dioxide is released from the capillary beds into the alveolar spaces by the process of diffusion - similarly, oxygen moves from the air spaces into the capillaries for transport to the tissues - this process is reversed at the tissue level where oxygen moves from the bloodstream into the tissues, and carbon dioxide moves from the tissues into the blood for transport to the lungs and removal from the body
Because infection is spread by __________ it is important to practice proper hand-washing, avoidance of finger-to-eyes or finger-to-nose contact, and use of nasal tissues.
- hand-to-hand contact, autoinoculation, and, possibly, aerosol particles
Local spread (mediastinal and pleural invasion) and metastasis (brain, bone, liver):
- hoarseness (laryngeal nerve compression) - superior vena cava syndrome (facial or arm edema and headache due to compression of the superior vena cava) - dysphagia (compression of the esophagus) - persistent, localized severe pain (pleural invasion) - headache, nausea, vomiting, seizures, dizziness, altered mental status (brain metastasis) - imaging findings and/or changes in organ function (liver, bone involvement)
What is hypercapnia?
- hypercapnia is an increase in carbon dioxide levels - the manifestations of hypercapnia consist of those associated with a decrease in pH (respiratory acidosis), vasodilation of blood vessels - including those in the brain, and depression of CNS function - a person with impaired respiratory function may have increased carbon dioxide production resulting from increased metabolic rate or high-carbohydrate diet
Hypoperfusion from Respiratory Failure
- hypoperfusion, regardless of cause, may result in respiratory failure through inadequate delivery of O2 to respiratory muscles along with excess respiratory muscle load (e.g., acidosis or sepsis) - mechanical ventilation is useful for diverting blood flow from overworked respiratory muscles to critical organs such as the brain, kidney, and GI tract
Hypoxemia
- hypoxemia refers to a decrease in blood oxygen levels that results in a decrease in tissue oxygenation - hypoxemia can result from hypoventilation, diffusion impairment, shunt, and ventilation-perfusion abnormalities - acute hypoxemia is manifested by increased respiratory cyanosis and impaired sensory and neurologic function - the body compensates for chronic hypoxemia by increased ventilation, pulmonary vasoconstriction, and increased production of red blood cells
What distinguishes idiopathic pulmonary fibrosis from sarcoidosis?
- idiopathic pulmonary fibrosis (IPF) is a type of interstitial lung disease defined as a specific form of chronic, progressive fibrosing interstitial pneumonia of unknown cause - it primarily occurs in older adults, is limited to the lungs, and associated with the histopathologic and/or radiologic pattern of usual interstitial pneumonia (UIP) - another name for this condition
Effects of ARDS
- in ARDS, pulmonary or systemic inflammation leads to release of cytokines and other proinflammatory molecules - the cytokines activate alveolar macrophages and recruit neutrophils to the lungs, which in turn release leukotrienes, oxidants, platelet-activating factor (PAF), and proteases - these substances damage capillary endothelium and alveolar epithelium, disrupting the barriers between capillaries and airspaces - edema fluid, protein, and cellular debris flood the airspaces and interstitium, causing disruption of surfactant, airspace collapse, ventilation-perfusion mismatch, shunting, and pulmonary hypertension - the airspace collapse more commonly occurs in dependent lung zones
Mucosal irritation is an important perpetrator in lung cancer -
- in addition to the direct carcinogenic effect, any irritant such as smoke leads to chronic inflammation and frequent infections in the respiratory tract, which in turn cause cellular changes - for example, in the mucosa, cigarette smoking causes a change from ciliated columnar epithelium to squamous cell epithelium - the alterations in the respiratory mucosa as it changes through metaplasia to dysplasia demonstrate the cell mutations caused by carcinogens and could perhaps lead to earlier diagnosis
Treatment for common cold
- in general, treatment for the common cold focuses on symptomatic relief and prevention of person-to-person spread and complications - the mainstays of therapy include rest, hydration, and management of symptoms - persons may limit their activity during the course of the infection, and clinical improvement occurs 48-72 hours after the prodrome of symptoms with the usual course lasting a week - typical incubation period is 2-3 days, and the period of contagion is during the incubation period continuing 5-7 days after cold symptoms appear
Pulmonary Infarct
- in pulmonary infarct a small single embolus affects a small segment of a lung, which becomes clogged with blood - this relatively benign condition can cause chest pain, hemoptysis, and slight fever - it appears on the chest x-ray as a shadow similar to that of pneumonia - prompt recovery usually occurs in a single infarct without sequelae - the significance of pulmonary infarct is as a predictor of larger, more serious emboli developing from the source of the small embolus
Each year, nearly 7,000 visits to EDs...
- in the United States by children younger than 11 years are associated with cough and cold medicines - treatment of children younger than 6 years should be supervised by a physician - children this age or younger should receive analgesics, cough suppressants, decongestants, and antihistamines - only on the advice of a physician - the US Food and Drug Administration (FDA) does not recommend the use of cough and cold medications in very young children (age <2 years) - In January 2008, the FDA completed its review of information regarding the safety of OTC cough and cold medicines in children younger than 2 years - this review resulted in a new recommendation - these drugs should not be used to treat children in this age group because serious and potentially life-threatening adverse effects can occur - in October 2008, the pharmaceutical industry voluntarily changed the labeling for OTC pediatric cough and cold drugs to include a statement that these drugs should not be used in children younger than 4 years - this action was in response to dosing errors, misuse, and overuse of OTC pediatric cough and cold medications Also important to remember - When a child has a viral illness, aspirin administration should be avoided to prevent Reye syndrome - a rare, but potentially fatal complication
Cystic Fibrosis and the Digestive Tract
- in the digestive tract, the first indication of abnormality may be meconium ileus in newborns, in which the small intestines of the neonate are blocked by mucus at birth, preventing the excretion of meconium shortly after birth - in the pancreas, the ducts of the exocrine glands become blocked, leading to a deficit of pancreatic digestive enzymes in the intestines - malabsorption and malnutrition result - eventually, the obstruction and backup of secretions cause damage to the pancreatic tissue, including the islets of Langerhans, resulting in diabetes mellitus in some individuals - the bile ducts of the liver may be blocked by viscid mucus, preventing bile from reaching the duodenum and interfering with digestion and absorption of fats and fat-soluble vitamins - ultimately, this abnormality also contributes to the general state of malabsorption, malnutrition, and dehydration - if obstruction is severe, the backup of bile behind the obstruction may cause inflammation and permanent damage to the liver in the form of biliary cirrhosis
Cystic Fibrosis Affect on Lungs
- in the lungs, the mucus obstructs airflow in the bronchioles and small bronchi, causing air trapping or atelectasis with permanent damage of the bronchial walls - because stagnant mucus is an excellent medium for bacterial growth - infections are common and add to the progressive destruction of lung tissue - organisms commonly causing infection in patients with CF include P. aeruginosa and S. aureus - bronchiectasis and emphysematous changes are seen frequently as fibrosis and obstructions advance - eventually respiratory failure or cor pulmonale develops
Second Stage of Response
- in the second stage of the allergic response, which occurs a few hours later, the increased leukocytes, particularly eosinophils, release additional chemical mediators such as leukotrienes, resulting in prolonged inflammation, bronchoconstriction, and epithelial damage - chemotactic factors and cytokines are released by mast cells and draw more white blood cells - the outcome is obstructed airways and marked hypoxia
The principal significance of disturbances of the pulmonary circulation is that they impose an increased workload on the right ventricle of the heart, which may cause hypertrophy and failure. Overload within this circuit is caused primarily by two mechanisms:
- increased blood flow to the lungs - increased pressure within the pulmonary circulation - increased blood flow is a characteristic feature of left-to-right shunts, occurring almost exclusively in congenital heart disease - two main pulmonary vascular disorders include pulmonary embolism and pulmonary hypertension
Developments of Emphysema
- infections develop frequently because secretions are more difficult to remove past the obstructions and airway defenses are impaired - pulmonary hypertension and cor pulmonale may develop in a late stage as the pulmonary blood vessels are destroyed and hypoxia causes pulmonary vasoconstriction
Causative agents of Pneumonia
- infectious agents (bacteria or viruses); noninfectious (aspiration of gastric secretions) - typical pneumonia - infection by bacteria that multiply extracellularly in the alveoli causing inflammation and exudation of fluid into the alveolar spaces - atypical pneumonia - infection caused by virus or mycoplasma that invades the alveolar septum and interstitium of the lungs
Influenza
- influenza is a viral infection that may affect both upper and lower respiratory tracts - there are three groups of the virus - Type A, the most prevalent pathogen, and types B and C - Influenza A and B cause epidemics, while influenza C is responsible for mild upper respiratory infections
Non-small cell lung cancer (NSCLC)
- involves 3 types: - Squamous cell carcinoma also has a strong correlation with smoking and originates in the central bronchi - it is possible to detect this in early stages and is associated with paraneoplastic syndromes; e.g., hypercalcemia. - adenocarcinoma is the most common type and originates in bronchiolar or alveolar tissues - it is associated with areas of scarring - old infarcts, metallic foreign bodies, wounds, and granulomatous infections - it has a poorer prognosis than squamous cell carcinoma - large cell carcinomas are highly anaplastic and occur in the periphery of the lung invading the subsegmental bronchi and larger airways - because it spreads early to distant sites, it has a poor prognosis
What factors affect the diffusion of gases?
- it is important to understand the factors that affect diffusion of gases - in addition to the partial pressure gradient, diffusion can be altered by the thickness of the respiratory membrane and the total surface area available for diffusion - when fluid accumulates in the alveoli or interstitial tissue, diffusion (particularly of oxygen) is impaired - normally the pressure in the pulmonary circulation is very low, reducing the risk of excessive fluid in the interstitial space and alveoli - the presence of extra fluid can impede blood flow through the pulmonary capillaries and increase surface tension in the alveoli - resulting in restriction of lung expansion - emphysema destroys part of the alveolar wall and fibrosis can reduce the surface area of the alveoli for adequate diffusion - if airflow into the alveoli is obstructed or the capillaries are damaged, the involved alveolar surface area becomes nonfunctional
What is compliance?
- it is the ability of the lungs to expand and the elasticity of the tissues - compliance is also affected by other factors - alveolar surface tension and shape, size, and flexibility of the thorax What effect does this have on ventilation during pregnancy and with aging? - space decreaeses
Lung cancers are one of the leading causes of cancer deaths...
- lung cancer accounts for about 27% of all cancer deaths and is by far one of the leading causes of cancer death among both men and women - overall, the chance that a man will develop lung cancer in his lifetime is about 1 in 13; for a woman, the risk is about 1 in 16 - these numbers include both smokers and non-smokers - lung cancer accounts for about 13% of all new cancers
Management of Sarcoidosis
- management may involve no treatment for asymptomatic patients to monitoring for patients with minimal symptoms and corticosteroids for stages II and III disease - corticosteroids may also be used to treat extrapulmonary sarcoidosis involving the heart, liver, eyes, kidneys, or central nervous system - other pharmacotherapy may include non-corticosteroid agents like methotrexate and other biologic agents
Small cell lung cancer (SCLC)
- manifests as small round to oval cells about the size of a lymphocyte - it grows in clusters with neither a glandular nor a squamous organization - it is strongly associated with cigarette smoking and with paraneoplastic syndrome, e.g., SIADH - by the time of diagnosis it has usually metastasized to the brain - it is highly malignant and infiltrates widely and disseminates early - it's usually not resectable - small cell lung cancers exhibit micrometastases and are staged as 1) limited - unilateral hemithorax or 2) extensive - extends beyond these boundaries - common sites of metastases from the lungs include the brain, bone, and liver
Coughing
- may result from irritation caused by nasal discharge dripping into the oropharynx, or from inflammation or foreign material in the lower respiratory tract, or from inhaled irritants, like tobacco smoke - an occasional cough is considered a normal event in a healthy person, but persistent cough may be evidence of a respiratory disease or chronic irritation - aspiration of food or fluid may cause a spasm of coughing - a cough may be described as dry or unproductive or productive - excess secretion may become infected and tends to obstruct airways - thick or sticky mucus is particularly difficult to raise from the lungs, especially in elderly or debilitated patients
Lung Cancer Statistics
- most lung cancer statistics include both small cell (SCLC) and non-small cell lung cancers (NSCLC) - excluding skin cancers, lung cancer is the second most common cancer in both men and women - in men, prostate cancer is more common, while in women breast cancer is more common - The American Cancer Society estimates for lung cancer in the United States for 2018 are: - About 234,030 new cases of lung cancer - 121,680 in men and 112,359 in women - An estimated 154,050 deaths from lung cancer - 83,550 in men and 70,500 among women - Each year, more people die of lung cancer than of colon, breast, and prostate cancers combined - lung cancer mainly occurs in older people - about 2 out of 3 people diagnosed with lung cancer are 65 or older; fewer than 2% of all cases are found in people younger than 45 - the average age at the time of diagnosis is about 70 - black men are about 20% more likely to develop lung cancer than white men - the rate is about 10% lower in Black women than in white women - both Black and white women have lower rates than men - but this gap is closing - the lung cancer rate has been dropping among men over the past 2 decades and has just recently begun to drop in women
Other Treatments if failure
- nasal endoscopy and computed tomography of the sinuses are reserved for circumstances that include a failure to respond to therapy as expected, spread of infection outside the sinuses, a question about the diagnosis, and/or when surgery is being considered - laboratory tests are not usually necessary and reserved for patients with suspected allergies, cystic fibrosis, immune deficiencies, mucociliary disorders, and similar disease states - surgery is indicated for extranasal spread of infection, evidence of mucocele or pyocele, fungal sinusitis or obstructive nasal polyposis, and is often performed in patients with recurrent or persistent infection not resolved by drug therapy
Normal Oxygen Levels
- normal oxygen levels provide a substantial reserve of oxygen in the venous blood - a marked decrease in oxygen (from approximately 105 to 60 mmHg) is necessary before the chemoreceptors respond to hypoxemia - this control mechanism can be important when individuals with chronic lung disease adapt to a sustained elevation in Pco2 and move to a hypoxic drive - such individuals are dependent on low oxygen levels rather than the normal slight elevation in carbon dioxide to stimulate inspiration - it's important for COPD patients to remain slightly hypoxic and not be given excessive amounts of oxygen ever
Here is the sequence of events for normal quiet inspiration and expiration:
- normal quiet inspiration begins with contraction of diaphragm and external intercostal muscles - diaphragm flattens and descends and increases the length of the thoracic cavity - external intercostal muscles raise the ribs and sternum up and outward - increasing the transverse and anteroposterior diameters of the thorax - increased size of thoracic cavity decreases pressure in the pleural cavity, alveoli, and airways - as ribs and diaphragm move, the attached parietal pleura pulls the adhering visceral pleura and lungs along with it - as visceral pleura moves outward, the elastic lungs expand with it, resulting in a decrease in air pressure inside the lungs - atmospheric pressure is greater than intra-alveolar pressure, so air flows from the atmosphere down the airways into the alveoli - normal expiration occurs when the diaphragm and external intercostal muscles relax resulting in decreased thoracic size - decreased thorax size, along with natural elastic recoil of alveoli results in an increased intra-alveolar pressure that is greater than atmospheric pressure - air flows out of alveoli into the atmosphere
Transport of Oxygen
- only 1% of total oxygen is dissolved in plasma because oxygen is relatively insoluble in water - this limits the ease with which oxygen can diffuse - the dissolved form of the gas is what diffuses from the alveolar air into the blood in the pulmonary capillaries and also diffuses into the interstitial fluid and the cells during internal respiration - most oxygen is transported reversibly bound to hemoglobin by the iron molecules - called oxyhemoglobin - when all 4 heme molecules in hemoglobin have taken up oxygen, the hemoglobin is fully saturated
TB is often prevalent in areas of...
- overcrowding and poor sanitation - the incidence of this condition was greatly reduced decades ago with the introduction of effective antibiotics - more recently, the number of TB cases in the US has seriously risen due to the influx of high numbers of infected immigrants, the homeless, individuals with AIDS who have a poor resistance to infection, and the development of drug-resistant bacteria
Partial Obstruction
- partial obstruction of the small bronchi and bronchioles results in air trapping and hyperinflation of the lungs - air passes into the areas distal to the obstruction and alveoli, but is only partially expired - because expiration is a passive process, less force is available to move air out, and forced expiration can collapse the bronchial wall, creating a further barrier to expiratory airflow - as residual volume increases, it becomes more difficult to inspire fresh air or to cough effectively to remove the mucus
Overview of Partial Pressure
- partial pressure is a measure of the concentration of the individual components in a mixture of gases - the total pressure exerted by the mixture is the sum of the partial pressures of the components in the mixture - the rate of diffusion of a gas is proportional to its partial pressure within the total gas mixture - diffusion of a gas into a liquid (or the reverse) occurs down a partial pressure gradient—that is, from a region of higher partial pressure to a region of lower partial pressure
What causes pulmonary embolism?
- perhaps the most serious and unpredictable condition affecting the pulmonary circulation is pulmonary embolism - it consists of occlusion of sections of the pulmonary arterial tree by thrombi carried in the bloodstream from the venous part of the circulation or from the right side of the heart - the sites of formation of thrombi vary - whereas inflammatory diseases of the veins are usually associated with thrombophlebitis, pulmonary embolism occurs much more frequently in veins not affected by inflammation - in susceptible individuals thrombi can form in veins, particularly during periods of inactivity - the veins most commonly affected by "silent" thrombosis are deep veins of the legs (not varicose veins) and veins in the pelvic organs (reproductive organs in women and the prostate in men) - because inactivity is an important cause of these thrombi, venous thrombosis and pulmonary emboli are particularly likely to develop in people who are immobile due to surgery, disease, or trauma
Perioperative Respiratory Failure
- perioperative respiratory failure is usually caused by atelectasis - effective means of preventing or treating atelectasis include incentive spirometry, ensuring adequate analgesia for chest and abdominal incisions, upright positioning, and early mobilization - atelectasis caused by abdominal distention should be alleviated based on the cause (e.g., nasogastric suction for excessive intraluminal air, paracentesis to evacuate ascites)
Pleural Pain
- pleural pain results from inflammation or infection of the parietal pleura - it is a cyclic pain - increases as the inflamed membrane is stretched during inspiration or coughing - friction rub may be heard as a soft sound produced as the rough membranes move against each other - pleural inflammation may be caused by lobar pneumonia or lung infarction
What is pleural effusion?
- pleuritis (or pleurisy) may precede or follow pleural effusion or occur independently - small amounts of fluid are drained from the pleural cavity by the lymphatics and have little effect on respiratory function - large amounts of fluid increase pressure in the pleural cavity and then cause separation of the pleural membranes with lack of cohesion during inspiration - expansion of the lung is prohibited resulting in atelectasis, particularly when fluid accumulates rapidly - a large amount of fluid causes atelectasis on the affected side and a shift of the mediastinal contents toward the unaffected lung - also limiting its expansion - a tracheal deviation indicates this shift. Venous return in the inferior vena cava and cardiac filling may be impaired because large effusions increase pressure in the mediastinum - effusions vary in type and mechanism depending on the primary problem - both lungs may be involved, but more often only one lung is affected because each lung is enclosed in a separate pleural membrane - the effects of effusion depend on the amount, type, and rate of accumulation of the fluid
Pneumonia
- pneumonia is an inflammation (or infection) of parenchymal structures of the lung - alveoli and bronchioles - it may develop as a primary acute infection in the lungs or secondary to another respiratory or systemic condition - in most cases, the organisms enter the lungs directly by inhalation (virus), resident bacteria spreading along the mucosa, or aspiration - classification of pneumonia may be based on the causative agent, anatomic location, pathophysiologic changes, or epidemiologic data
Pneumothorax
- pneumothorax refers to air in the pleural cavity - the presence of air at atmospheric pressure in the pleural cavity and the separation of the pleural membranes prevent expansion of the lung - leading to atelectasis - when pneumothorax is caused by malignant tumor or trauma, fluid or blood may also be present in the cavity - Chest x-rays can determine the type and extent of pneumothorax
What is the cause of pulmonary hypertension?
- pulmonary hypertension is a rare lung disorder in which the arteries that carry blood from the heart to the lungs become narrowed, making it difficult for blood to flow through the vessel - as a result, the blood pressure in the pulmonary arteries rises far above normal levels - this abnormally high pressure strains the right ventricle of the heart, causing it to expand in size - overworked and enlarged, the right ventricle gradually becomes weaker and loses its ability to pump enough blood to the lungs - this can lead to the development of right heart failure - cor pulmonale - pulmonary hypertension occurs in individuals of all ages, races, and ethnic backgrounds, although it is much more common in young adults and is approximately twice as common in women as in men
What are the pulmonary vascular disorders?
- pulmonary vascular diseases affect the blood vessels in the lungs - they are caused by clotting, scarring, or inflammation of the blood vessels that affect the ability of the lungs to take up oxygen and release carbon dioxide - these diseases may also affect heart function. Pressure in the pulmonary circulation is influenced by many factors, in contrast to pressure in the systemic circulation, which is controlled solely by constriction and relaxation of the arterioles - the arterial pressure in the pulmonary circulation is roughly one-fifth of the systemic circulation - with these differences it is not surprising that abnormalities affecting the pulmonary circulation are unlike those affecting other regions of the circulation
What are pulmonary volumes?
- pulmonary volumes are a measure of ventilatory capacity in that they measure the air moving in and out of the lungs with normal or forced inspiration and expiration - pulmonary volumes can change with disease processes and are helpful in monitoring the patient's progress or response to treatment - for example, impaired expiration can cause an increase in residual volume with increased carbon dioxide levels in body fluids
In individuals with extrinsic asthma, the antigen reacts with IgE on the previously sensitized mast cells in the respiratory mucosa resulting in
- release of histamine, kinins, prostaglandins, and other chemical mediators, which then cause inflammation, bronchospasm, edema, and increased mucus secretion - the reaction also stimulates branches of the vagus nerve causing reflex bronchoconstriction
What are common upper respiratory infections?
- respiratory illnesses, which are mostly viral infections, account for almost 50% of all acute illnesses; and respiratory infections account for more than 80% of all infections - most disorders of the upper respiratory tract are not life threatening - upper respiratory infection is a broad term referring to several infectious diseases of the upper respiratory tract and is the most common cause for lost days of work for adults
Rhinosinusitis
- rhinosinusitis can be divided among four subtypes: acute, recurrent acute, subacute and chronic, based on patient history and a limited physical examination - a viral upper respiratory infection is the most common precursor to bacterial rhinosinusitis, followed by sinus obstruction from the mucosal edema of inhalant allergies and anatomic factors
Sarcoidosis
- sarcoidosis is a multisystem inflammatory disease also of unknown cause - it affects adults younger than 40 years of age - clinical manifestations vary with the extent and severity of organ involvement. It can be asymptomatic and only detected incidentally on chest x-ray - there are systemic complaints of fever and anorexia in 45% of the cases - pulmonary complaints of dyspnea on exertion, cough, chest pain and hemoptysis in 50% of the cases - the pulmonary findings can range from normal to rales per auscultation to exertional oxygen desaturation - there also may be dermatologic manifestations, ocular involvement, heart failure, osseous involvement and cranial nerve palsies
Secondary Tuberculosis
- secondary TB occurs when an individual is reinfected with the Mycobacterium or the primary disease is reactivated due to a decline in the person's resistance - antibodies formed during the primary stage of the disease activate quickly causing larger areas of necrosis in the lung tissue - a cell-mediated hypersensitivity reaction - the person becomes symptomatic due to bronchial dissemination and cavitation causing pleural effusion and tuberculous empyema - the tubercle mass becomes liquefied and is coughed up, leaving a cavity in the lung tissue - frequent coughing can rupture capillaries in the lung tissue leading to hemoptysis (spitting up blood) - coughing fills the surrounding air with contagious bacteria and increases disease spread - as large cavities are formed, the ability to oxygenate blood is decreases - the individual becomes dyspneic and cachectic with a general appearance of being "consumed" by the disease - the reason TB was called "consumption"
Secondary Metastatic Cancer
- secondary metastatic cancer develops frequently in the lungs because the venous return and lymphatics bring tumor cells from many distant sites in the body to the heart and then into the pulmonary circulation - this provides the first small blood vessels and a hospitable environment in which tumor cells can lodge
Small repeated pulmonary emboli
- small, repeated pulmonary emboli may feed the pulmonary circulation over a period of weeks, months, or years, causing gradual elevation of pressure in the pulmonary artery and leading to chronic, irreversible pulmonary hypertension - while uncommon, this severe, usually fatal form of pulmonary hypertension is almost indistinguishable from primary pulmonary hypertension
What are common signs and symptoms of upper respiratory disorders?
- sneezing - coughing - sputum - stridor
Status asthmaticus
- status asthmaticus is a persistent severe attack of asthma that does not respond to therapy - it is often related to inadequate medical treatment - it may be fatal when severe hypoxia and acidosis leads to cardiac arrhythmias or central nervous system depression
Symptoms of Pulmonary Hypertension
- symptoms of pulmonary hypertension do not usually occur until the condition has progressed - the first symptom of pulmonary hypertension is usually dyspnea with everyday activities, such as stair climbing - fatigue, dizziness, and syncope may also be symptoms - edema in the lower extremities, abdominal ascites, cyanosis, and chest pain may occur as strain on the heart increases - manifestations range in severity and a patient may not experience all of the signs/symptoms - in more advanced stages of the disease, even minimal activity will produce some of the signs/symptoms - additional manifestations include: arrhythmia and palpitations. Eventually, it may become difficult to carry out any activities as the disease worsens
Bronchiectasis Effects
- the airways are damaged in such a way as to cause them to widen and become flabby and scarred - it usually results from an infection or other condition that injures the walls of the airways or prevents the airways from clearing mucus - in bronchiectasis, the airways slowly lose their ability to clear out mucus resulting in mucus accumulation and creation of an ideal environment in which bacteria can grow - as a result, the individual experiences repeated, serious lung infections - with each infection more airway damage occurs - over time, the airways lose the ability to move air in and out - bronchiectasis can lead to serious health problems, such as respiratory failure, atelectasis and heart failure
In both types, flooded or collapsed airspaces allow no inspired gas to enter so...
- the blood perfusing those alveoli remains at the mixed venous O2 content no matter how high the fractional inspired O2 (FIO2) - this effect ensures a constant admixture of deoxygenated blood into the pulmonary vein - and thus, arterial hypoxemia
Chemical factors are most important in respiratory control. Chemoreceptors sense changes in the levels of carbon dioxide, hydrogen ions, and oxygen in blood or cerebrospinal fluid -
- the central chemoreceptors in the medulla respond quickly to slight elevations in Pco2 (from a normal 40-43 mmHg) or to decreased pH (increased H+) in the cerebrospinal fluid - the peripheral chemoreceptors located in the carotid bodies at the bifurcation of the common carotid arteries in the aortic body in the aortic arch, are sensitive to decreased oxygen levels in arterial blood as well as to low pH
Effects of Chronic Bronchitis
- the chronic irritation and inflammation lead to fibrosis and thickening of the bronchial wall and further obstruction - secretions pool distal to obstructions and are difficult to remove - oxygen levels are low - severe dyspnea and fatigue interfere with nutrition, communication, and daily activities leading to general debilitation - pulmonary hypertension and cor pulmonale are common
Common Cold
- the common cold is an acute inflammation of the mucous membranes of the upper respiratory tract - it occurs more frequently than any other respiratory tract infection and is associated with hundreds of different viruses - morbidity is related to its prevalence worldwide, rather than its severity - about 10-15% of adult colds are caused by viruses also responsible for other, more severe respiratory illnesses - the causes of 20-30% of adult colds remain unidentified, and the same viruses that produce colds in adults appear to cause colds in children
Management of Idiopathic Pumlonary fibrosis
- the condition is managed by smoking cessation, oxygen therapy for patients with hypoxemia, and vaccination against influenza and pneumococcal infection - pharmacotherapy may include steroids, immunosuppressants, tyrosine kinase inhibitors, and antibiotics - the mean survival after diagnosis is 3-5 years. Lung transplantation may be an option
The cough reflex
- the cough reflex is controlled by a center in the medulla and consists of coordinated actions that inspire air and then close the glottis and vocal cords - this is followed by forceful expiration in which the glottis is opened and the unwanted material is blown upward and out of the mouth - in some cases the product of a cough is swallowed - the effectiveness of the cough depends on the strength of the muscle action during both inspiration and expiration
Treatment of Rhinosinusitis
- the general treatment goals are to control infection, diminish tissue edema, and reverse sinus ostial obstruction so the mucopus can drain - in most instances, therapy is initiated based on the classification of the rhinosinusitis - antibiotic therapy, supplemented by hydration and decongestants, is indicated for 7-14 days in patients with acute, recurrent acute, or subacute bacterial rhinosinusitis - for patients with chronic disease, the same treatment regimen is indicated for an additional 4 weeks or more, and a nasal steroid may also be prescribed if inhalant allergies are known or suspected
Process of Tuberculosis
- the infection begins with a primary lesion in the lungs - however, an acute inflammation does not occur because the Mycobacterium does not attract PMNs - lymphocytes and macrophages are attracted to these encapsulated bacteria and begin producing antibodies and walling off the infection by forming a granuloma called a tubercle - this circumscribed granulomatous lesion is called a Ghon focus - the tubercle including dead bacteria, lung tissue, and immune cells that together exhibit a cheesy appearance - caseous necrosis - free tubercle bacilli or macrophage-engulfed tubercles drain into lymph channels and along tracheobronchial lymph nodes of the infected lung forming caseous granulomas - the Ghon focus and granulomas form the Ghon complex
Surfactant
- the inside surfaces of the alveoli are coated with a very small amount of fluid containing surfactant, produced by specialized cells in the alveolar wall - Surfactant has a detergent action that reduces surface tension of the alveolar fluid, facilitating inspiration and preventing total collapse of the alveoli during expiration - when inspiration is complete, the process of expiration reverses airflow in the passageways, forcing air out of the alveoli and up the bronchi, trachea, and nose
Specifics of the lungs
- the lungs are cone-shaped structures positioned on either side of the heart - the mediastinum is the region in the center of the chest, which contains the heart, the major blood vessels, the esophagus, and the trachea - the dome-shaped muscular diaphragm forms the inferior boundary - the right lung is divided into three lobes and the left lung into two lobes because of the position of the heart, and each lobe is then divided into segments - the lung tissue (lungs, bronchi, and pleurae) is nourished by the bronchial arteries, which branch from the thoracic aorta
What are the clinical manifestations?
- the onset of lung cancer is insidious because the early signs of cancer are often masked by signs of the predisposing factor, such as a "smoker's cough" - in many cases the cancer has already metastasized before diagnosis, and it's the signs of a metastatic tumor that lead to the diagnosis There are 3 possible categories of lung cancer manifestations: 1) Involvement of the lung and adjacent structures from irritation and airway obstruction 2) Local spread (mediastinal and pleural invasion) and metastasis (brain, bone, liver) 3) Paraneoplastic syndrome is more often associated with SCLC and indicated by the signs of an endocrine disorder related to the specific hormone secreted; however, NSCLC also synthesizes bioactive products causing some paraneoplastic syndromes 4) Hematologic disorders - migratory thrombophlebitis, nonbacterial endocarditis, disseminated intravascular coagulation (DIC) - highly associated with adenocarcinoma (NSCLC)
How is ventilation controlled?
- the primary control centers for breathing are located in the medulla and the pons - the inspiratory center in the medulla controls the basic rhythm by stimulating the phrenic nerves to the diaphragm and the intercostal nerves to the external intercostal muscles - these stimuli occur spontaneously in a rhythmic fashion, each lasting about 2 seconds - the expiratory center in the medulla appears to function primarily when forced expiration is required because normal quiet expiration is just a cessation of activity following each inspiration - additional centers in the pons play a role in coordinating inspiration, expiration, and the intervals for each
What are hypoxemia and hypercapnia?
- the primary functions of the respiratory system are to remove appropriate amounts of carbon dioxide from the blood entering the pulmonary circulation and provide adequate amounts of oxygen to blood leaving the pulmonary circulation - this is accomplished through the process of ventilation (air moves into and out of the lungs) and diffusion (gases move between the alveoli and the pulmonary capillaries) - although both affect gas exchange, oxygenation of the blood largely depends on diffusion, while removal of carbon dioxide depends on ventilation
Pulmonary circulation is composed of...
- the pulmonary arteries, which bring venous blood from the right ventricle of the heart to be oxygenated - the pulmonary capillaries, in which diffusion or gas exchange occurs - the pulmonary veins, which return the oxygenated blood to the left atrium of the heart - the oxygenated blood moves from the left ventricle of the heart, which pumps the blood into the aorta, and the systemic circulation
Why do we classify respiratory failure?
- the respiratory system oxygenates and eliminates CO2 from venous blood - thus, a useful classification of respiratory failure is whether the principal abnormality is inadequate oxygenation or inadequate CO2 elimination (which means inadequate ventilation), although many disorders affect both - respiratory failure frequently necessitates mechanical ventilation
Cystic Fibrosis and Glands
- the salivary glands are often mildly affected, with secretions that are abnormally high in sodium chloride and mucous plugs that cause patchy fibrosis of the submaxillary and sublingual glands - the sweat glands are also affected, producing sweat that is very high in sodium chloride content - this is usually not a serious problem unless hot weather or strenuous exercise lead to excessive loss of electrolytes in the sweat - the reproductive system may be affected, with thick mucus obstructing the vas deferens in males or the cervix in females, leading to sterility or infertility - in some males the testes and ducts do not develop normally
Emphysema
- the significant change in emphysema is the destruction of the alveolar walls and septae, which leads to large, permanently inflated alveolar air spaces Emphysema may be further classified by the specific location of the changes - Centriacinar (centrilobular) - bronchioles in central part of respiratory lobule with initial preservation of alveolar ducts and sacs Panacinar - initial involvement of peripheral alveoli; later extends to involve more central bronchioles (alpha1-antitrypsin deficiency)
Thorax
- the thorax, consisting of ribs, vertebrae, and sternum, provides a rigid protection wall for the lungs - the upper seven pairs of ribs articulate with the vertebrae and are attached to the sternum by costal cartilage - the next three pairs of ribs are connected to the costal cartilage of the seventh rib, not directly to the sternum - the last two ribs, the eleventh and twelfth pairs, are attached only to vertebrae - called floating ribs - between the ribs are located the external and internal intercostal muscles, which move the thoracic structures during ventilation
Transport of CO2
- the waste product from cell metabolism - carbon dioxide - is transported in several forms - about 7% is dissolved in plasma and easily diffuses across membranes - approximately 20% is loosely and reversibly bound to hemoglobin - attached to the globin portion - the majority of carbon dioxide resulting from cell metabolism diffuses into the RBCs where it briefly transitions to carbonic acid and is immediately converted into bicarbonate ions - these bicarbonate ions can then diffuse back into the plasma to function in the buffer pair - a ratio of 20 parts bicarbonate ion to 1 part carbonic acid maintains blood pH at 7.35 - so carbon dioxide plays a major role in the control of blood pH through this buffer system
What are the pathologic fungi that induce delayed cell-mediated hypersensitivity responses in respiratory infections?
- there is a great diversity of respiratory pathogens, and fungi account for only a small portion of community-acquired and nosocomial types of pneumonia - but, fungal respiratory infections become a concern as the number of immunosuppressed persons increase - fungi may colonize body sites without producing disease or they may be a true pathogen and cause a variety of clinical manifestations
RSV prevention
- there is a medicine that can help protect some babies from the respiratory syncytial virus, particularly for those who have a higher risk for serious illness as a result of an infection - the medication is palivizumab and consists of a series of monthly shots during RSV season
What are the normal structures of the respiratory system?
- this system consists of the thorax, lungs, and conducting airways - the thorax houses the lungs and mediastinum - heart and vessels - respiratory system structures include lungs, 12 pairs of ribs, part of the vertebral column, the sternum, and the diaphragm - the lungs are two spongy organs divided into three lobes in the right lung and two lobes in the left lung - the lungs lie in the pleural cavity of the thorax, which is lined with the pleural membrane - the lungs are also covered with a second pleural membrane - a lubricating liquid is contained between the two pleurae and prevents friction during breathing and lung expansion
Total Obstruction
- total obstruction of the airway results when mucus plugs completely block the flow of air in the already narrowed passage - this leads to atelectasis or non-aeration of the tissue distal to the obstruction - the air in the distal section diffuses out and is not replaced and that section of the lung collapses - both partial and total airway obstruction lead to marked hypoxia - oxygen levels are further depleted by the increased demand for oxygen to supply increased muscle activity and the stress response as the individual fights for air - both respiratory and metabolic acidosis occurs from severe respiratory impairment - hypoxemia causes vasoconstriction in the pulmonary blood vessels, reducing blood flow through the lungs and increasing the workload of the right side of the heart
Treatment for Influenza
- treatment is symptomatic and supportive unless bacterial infection occurs - antiviral drugs, such as amantadine, zanamivir, or oseltamivir taken by adults in the first 2 days, may reduce symptoms and duration as well as the risk of infecting others - these drugs are important in the control of flu outbreaks in hospitals or nursing homes - prevention of flu by vaccination is recommended for all individuals - usually, if the flu develops after immunization, it is milder - it will take up to 2-3 weeks after vaccination for immunity to develop
What are some general manifestations of lower respiratory tract infections?
- we already discussed sneezing, coughing, and mucus and sputum production in our discussion of upper respiratory infections - normally sputum is clear, thin and colorless or cream color Other symptoms include: - Breathing patterns - Kussmaul or wheezing - Breath sounds - rales or rhonchi - Dyspnea - Cyanosis - Pleural pain - Clubbed fingers - hypoxemia
5. Scenario A: A 58-year-old man has been complaining of being tired all the time. He says that he sleeps through the night but "just doesn't feel rested" when he wakes up. His wife accompanied him to the clinic today and says that the her husband snores so loud that the kids hear him, and their bedroom is downstairs. Lately, she has been noticing that he has long pauses in between breaths, and when he checked his blood pressure at the drugstore, it was elevated. A. What should be considered in this case? B. What associated risks would need to be discussed with the patient and his wife at this time?
A) Based on his symptoms and what his wife has reported, he is presenting with sleep apnea. B) What makes this potentially alarming is that sleep apnea may place the patient in a higher-risk category for secondary pulmonary hypertension. Secondary pulmonary hypertension is more common than primary. The pathogenesis of primary pulmonary hypertension should also be understood. Pulmonary hypertension as a disorder of respiratory function must be understood from both a respiratory as well as vascular response. A review of the circulatory system, paying attention to vascular circulation as it relates to the pulmonary system. All of the patient's symptoms currently point toward potential hypoxic events occurring. Hypoxemia is a major contributing factor to pulmonary hypertension. The difference between hypoxia, hypoxemia, and hypercapnia must be understood. Therefore, one can assume that ventilation and gas exchange must be reviewed to comprehend the changes in oxygen transport. Of course, the patient would have to go through other diagnostic testing to confirm this diagnosis. Sleep apnea studies would confirm his condition.
Scenario C: Duane Foster is a 30-year-old man, who is brought to the ED with a knife wound to the chest. On visual inspection, asymmetry of chest movement during inspiration, displacement of the trachea, and absence of breath sounds on the wound side are noted. His neck veins are distended, and his pulse is rapid and weak. A diagnosis of tension pneumothorax is made A. Explain the observed respiratory and cardiovascular function in terms of the impaired lung expansion and the air that has entered the chest as a result of the injury. B. What type of emergent treatment is necessary to save this man's life?
A) Tension pneumothorax occurs when the intrapleural pressure exceeds atmospheric pressure. This scenario describes an injury to the chest that permits air to enter but not leave the pleural space. This results in a rapid increase in pressure in the chest with compression atelectasis of the unaffected lung, a shift in the mediastinum to the opposite side of the chest and compression of the vena cava with impairment of venous return to the heart and reduced cardiac output. B) Emergency treatment of tension pneumothorax involves the prompt insertion of a large-bore needle or chest tube into the affected side of the chest along with one-way valve drainage or continuous chest suction to aid in lung reexpansion.
Scenario A: It is flu season, and although you had a flu shot last year, you have not had one this year. Imagine yourself experiencing an abrupt onset of fever, chills, malaise, muscle aching, and nasal stuffiness. A) Which of these listed symptoms would lead you to suspect you are coming down with the flu?
A) The influenza virus has symptoms that are indistinguishable from other viral infections. But, one distinguishing feature of an influenza viral infection is the rapid onset of profound malaise, sometimes in as little as 1 to 2 minutes. The classic presentation of viral influenza includes abrupt onset of fever and chills, malaise, muscle aching, headache, profuse watery nasal discharge, nonproductive cough, and sore throat. So, in this scenario, all of the listed symptoms would lead you to believe you are coming down with the flu.
Scenario B: The nurse is working in the ED when the paramedics call in and report that they are in route with Timothy Thompson, who was involved in a motor vehicle accident. He is presently unconscious and receiving supplemental oxygen. Vital signs are BP 110/68; HR 100; RR 10 and shallow; T 98o F. A. What additional information will be helpful? B. Mr. Thompson was the driver, and he was wearing seatbelt. His compact car collided head-on with a full-size pickup truck. There was not evidence of alcohol or drug involvement, and the only history that can be obtained is that he has a chronic lung problem. Why would the nurse need to obtain more information about his lung problem? C. Assessment reveals absent breath sounds on the right side with minimal chest movement. What does the nurse suspect and why?
A) Was he the driver? Was he wearing a seat belt? Was he thrown from the vehicle? Where was the point of impact? What are his injuries? What is his past medical history? Any medications? Was he under the influence of drugs or alcohol? B) If he has chronic obstructive pulmonary disease, supplemental oxygen should be kept at 1 to 2 L to prevent hypoventilation and further carbon dioxide retention. C) He most likely sustained a traumatic pneumothorax from the impact of the steering wheel.
He speaks and understands very little English, and his native language is Spanish. He has been staying in the homeless shelter since his arrival, and he denies any significant health issues. B) Is it significant that he has been cleaning chicken houses? why or why not? A tuberculin skin test was administered, and 2 days later, there is 14 mm of induration. C) How would the nurse interpret his TB skin test? D) How will definitive diagnosis of TB be made? E) What are some risk factors for TB? F) A diagnosis of tuberculosis is confirmed in Mr. Ruiz, and he is prescribed a combination of drugs for at least 6 months. What is the rationale for multiple drugs and the length of treatment?
B) Yes. A fungal infection of the lungs will need to be ruled out. Manifestations are similar to tuberculosis. C) His TB skin test is positive, which means he has been exposed to TB, he has a nontuberculosis mycobacterial infection, or he has received the bacillus Calmette-Guérin (BCG) vaccine. D) The organism will have to be identified from sputum cultures of DNA amplification techniques. A chest x-ray is also helpful. E) Some risk factors include the following: Immunocompromised status Close living arrangements since it is spread via droplet nuclei F) The tubercle bacillus multiplies slowly and has a high rate of mutation. Multiple drug therapy is helpful for decreasing the risk of developing a resistance to any one drug.
Bacterial (e.g., S. pneumoniae) pneumonia is commonly manifested by a cough productive of sputum, whereas with atypical (e,g., M. pneumoniae) pneumonia, the cough is usually nonproductive or absent. Can you explain?
Bacterial pneumonia: The most common cause of bacterial pneumonia is S. pneumoniae. Pathology resulting from infection by the bacteria causes the alveoli to become filled with protein-rich edema fluid. Capillary congestion follows with a massive outpouring of polymorphonuclear leukocytes and red blood cells. Macrophages phagocytose the polymorphonuclear cells, red blood cells, and other cellular debris. The alveolar exudate is removed with productive coughing. Atypical pneumonia: Atypical pneumonia produces patchy inflammatory changes that are confined to the alveolar septum and the interstitium of the lung (not the alveoli). The term "atypical" denotes a lack of lung consolidation and production of moderate amounts of sputum. There is a lack of alveolar infiltration; hence, the cough (if present at all) is nonproductive.
Discuss the difference between these 2 categories of pneumonia - define, identify cause and primary organisms, and treatment.
Because of the overlap in symptomatology and changing spectrum of infectious organisms involved, pneumonia is increasingly being classified as community-acquired and hospital-acquired (nosocomial) pneumonia, depending on the setting in which they occur. The term community-acquired pneumonia is used to describe infections from organisms found in the community rather than in the hospital or nursing home. It is defined as an infection that begins outside the hospital or is diagnosed within 48 hours after admission to the hospital in a person who has not resided in a long-term care facility for 14 days or more before admission. Community-acquired pneumonia may be further categorized according to the risk of mortality and need for hospitalization based on age, the presence of coexisting disease, and severity of illness, using physical examination, laboratory, and radiologic findings. Community-acquired pneumonia may be either bacterial or viral. The most common cause of infection in all categories is S. pneumoniae. Other common pathogens include H. influenzae, S. aureus, and gram-negative bacilli. Treatment involves the use of appropriate antibiotic therapy. Empiric antibiotic therapy, based on knowledge regarding an antibiotic's spectrum of action and ability to penetrate bronchopulmonary secretions, often is used for persons with community-acquired pneumonia who do not require hospitalization. Hospitalization and more intensive care may be required depending on the person's age, preexisting health status, and severity of the infection. Hospital-acquired, or nosocomial, pneumonia is defined as a lower respiratory tract infection that was not present or incubating on admission to the hospital. Usually, infections occurring 48 hours or more after admission are considered hospital-acquired. Persons requiring intubation and mechanical ventilation are particularly at risk, as are those with compromised immune function, chronic lung disease, and airway instrumentation, such as endotracheal intubation or tracheotomy. Ventilator-associated pneumonia is pneumonia that develops in mechanically ventilated patients more than 48 hours after intubation. Most hospital-acquired infections are bacterial. The organisms differ from those responsible for community-acquired pneumonia and reflect those present in the hospital environment. Gram-negative rods (Enterobacteriaceae and Pseudomonas species) and S. aureus are the most common isolates. Many of these organisms have acquired antibiotic resistance and are thus difficult to treat.
Tuberculosis Disease Card
Definition/Cause: - infectious disease caused by Mycobacterium tuberculosis - resistant to destruction, persists in necrotic and calcified lesions for prolonged periods and capable of reinstating growth Transmission - inhalation of mycobacterium-containing droplet nuclei from air - overcrowded living conditions increase risk Pathogenesis: - tubercle bacillus has no known antigens to stimulate early immunoglobulin response; healthy host mounts a delayed-type cell-mediated immune response - walls off tubercle bacilli to prevent active tuberculosis; immunocompromised host with impaired cell-mediated immunity - develop active TB Manifestations: - Primary TB - initially asymptomatic with development of latent tuberculosis infection (LTBI) - about 5% (young children, immunocompromised) develop progressive primary TB with destruction of pulmonary tissue and spread to multiple sites within lung tissue Insidious onset - fever, weight loss, fatigue, night sweats Abrupt onset - high fever, pleuritis, lymphadenitis - Secondary TB - reinfection from inhaled droplet nuclei or reactivation of healed primary lesion Coughing, hemoptysis Disease progression - formation of large cavities Dyspnea, cachexia Diagnosis: - identification of organism from cultures of M. tuberculosis nucleic acid (DNA) amplification techniques - culture specimens obtained from early morning sputum, gastric aspirations, bronchial washings during fiberoptic bronchoscopy - cultures require up to 12 weeks to grow - chest x-ray - extent of lung involvement - TB skin testing - identify latent tuberculin infection Treatment: - Goal - eliminate tubercle bacilli, prevent spread of infection, prevent development of drug-resistant forms of disease - multiple drug therapy for 6-24 months may include all or some - isoniazid, ethambutol, pyrazinamide, rifampin Indication for treatment: active TB, contact with cases of active TB and at risk, prophylaxis for latent TB without active disease
Pneumococcal Pneumonia
Definition/Cause: - lower respiratory tract infection with Streptococcus pneumoniae Clinical Manifestations: - Healthy - sudden onset of malaise, severe, shaking chills, fever (106o F), watery sputum, limited breath sounds with fine crackles, sputum blood-tinged or rust-colored to purulent, pleuritic pain - Elderly - loss of appetite, deterioration of mental status Diagnosis: - history and physical - symptoms/signs; lab findings - isolation of organism in peripheral sputum, blood samples, pleural fluids Treatment: - antibiotic sensitive to S. pneumonia Prevention: - polysaccharide pneumococcal vaccine >65 years, immunocompromised, cigarette smoker, chronic illness, special environment or social settings, residents of nursing homes/LTC facilities, immunocompromised >2 years of age with hematologic cancer, nephrotic syndrome, chronic kidney disease, immunodeficiency status; 2nd dose 5 yrs after first given
Pulmonary Embolism Disease Card
Definition/Etiology: - blood-borne substance lodges in a branch of the pulmonary artery and obstructs blood flow; e.g., thromboemboli originating in systemic venous system (DVT), air injected during intravenous infusion, fat mobilized from bone marrow after fracture or traumatized fat depot or amniotic fluid entering maternal circulation during childbirth Clinical Manifestations: - small emboli - clinically silent and unrecognized unless the person is compromised (elderly or acutely ill) moderate-sized emboli - dyspnea, pleuritic pain, apprehension, slight fever, productive cough of blood-streaked sputum, tachycardia - massive emboli - sudden collapse, crushing substernal chest pain, shock, possible loss of consciousness, rapid and weak pulse, hypotension, jugular venous distention (JVD), cyanosis, and diaphoresis Diagnosis: - signs/symptoms, blood gases, venous thrombosis studies, D-dimer testing, lung scans, helical CT scans of chest, pulmonary angiography Treatment: - thrombolytic therapy followed by anticoagulant therapy for thromboemboli; large emboli - sustain life and restore pulmonary blood flow
Legionnaire Disease
Definition: - bronchopneumonia caused by a gram-negative rod, Legionella pneumophilia; consolidation in lung tissues that impairs gas exchange - form of bronchopneumonia with infection by acquiring the organism from the environment Cause: - pathogen in water or condensation - L. pneumophilia, aerosolized and inhaled or aspirated risk factors - chronic disease, impaired cell-mediated immunity Manifestations: - 2-10 days after infection - abrupt onset of malaise, weakness, lethargy, fever, dry cough; confusion; hyponatremia; diarrhea; arthralgias; fever >104oF and relative bradycardia (slow heart rate)* *[Note: Often higher fevers are accompanied by faster heart rate] Diagnosis: - history and physical exam findings - signs/symptoms; chest x-ray; lab - sputum, urine antigen tests, sputum fluorescent antibody for rapid detection of serotype 1 (less sensitive than culture for other serotypes) Treatment: - early treatment to decrease the risk of mortality; antibiotic specific for the organism
ALI/ARDS Disease Card
Definition: - clinical syndrome characterized by diffuse epithelial cell injury and increased permeability of the alveolar-capillary membrane Etiology: - aspiration of gastric contents, major trauma (with or without fat emboli), sepsis, secondary to pulmonary or nonpulmonary infections, acute pancreatitis, hematologic disorders, metabolic events, reactions to drugs/toxins, chronic alcohol abuse Clinical Manifestations: - severe dyspnea with rapid onset, hypoxemia refractory to treatment with supplemental oxygen, and pulmonary infiltrates; systemic response with multiple organ failure Diagnosis: - CXR demonstrating diffuse bilateral infiltrates of lung tissue in absence of cardiac dysfunction Treatment: - supply oxygen to vital organs and provide supportive care until condition reversed and lungs heal; assisted ventilation with high concentrations of oxygen; positive end-expiratory pressure breathing Prognosis is highly variable and depends on etiology of respiratory failure, severity of disease, age, and chronic health status - overall, mortality in ARDS was very high (40 to 60%) but has declined in recent years to 25 to 40%, probably because of improvements in mechanical ventilation and in treatment of sepsis - however, mortality remains very high (>40%) for patients with severe ARDS - most often, death is not caused by respiratory dysfunction, but by sepsis and multiple organ failure - persistence of neutrophils and high cytokine levels in bronchoalveolar lavage fluid predict a poor prognosis - mortality otherwise increases with age, presence of sepsis, and severity of preexisting organ insufficiency or coexisting organ dysfunction - pulmonary function returns to near normal in 6 to 12 months in most ARDS patients who survive; however, patients with a protracted clinical course or severe disease may have residual pulmonary symptoms, and many have persistent neuromuscular weakness
Interstitial Lung Disease Card
Definition: - diffuse parenchymal lung disease or restrictive lung disorder is a diverse group of lung disorders producing similar inflammatory and fibrotic changes in the interstitium or interaveolar septa of the lung resulting in stiff and noncompliant lungs Etiology: - hypersensitivity pneumonitis, pneumoconiosis, sarcoidosis, radiation therapy, certain drugs, immunologic lung disorders accompanying rheumatoid arthritis or scleroderma Idiopathic pulmonary fibrosis - diffuse patchy interstitial fibrosis causing collapse of alveolar walls and formation of cystic spaces Sarcoidosis - multisystem disorder with granulomas in tissues and organs, particularly the lungs and intrathoracic lymph nodes Clinical Manifestations: - dyspnea, tachypnea, cyanosis, nonproductive cough, clubbing of fingers and toes, reduced lung volumes Diagnosis: - person/family history, serial chest x-rays, biopsy by surgical incision - open or video-assisted thoracoscopic surgery (VATS) - or bronchoscopy, bronchoalveolar lavage, gallium lung scan Treatment: - identify and remove injurious agent, suppress inflammatory response, prevent disease progression, provide supportive therapy for advanced disease - corticosteroid drugs, oxygen therapy, and antibiotics for prevention of infection
Chronic Obstructive Pulmonary Disease Card
Definition: - group of respiratory disorders characterized by chronic and recurrent obstruction of airflow in pulmonary airways Etiology: - smoking or exposure to occupational dusts and chemicals; recurrent respiratory infections, asthma or airway hyper-responsiveness Emphysema - loss of lung elasticity and abnormal enlargement of air spaces distal to terminal bronchioles with destruction of alveolar walls and capillary beds Chronic bronchitis - major and small airway obstruction associated with chronic irritation from smoking and recurrent infections; hypersecretion of mucus in large airways associated with hypertrophy of submucosal glands in trachea and bronchi; history of chronic productive cough persisting for 3 consecutive months in 2 consecutive years Manifestations: - moderate to severe respiratory impairment greater on expiration resulting in increased work of breathing and decreased effectiveness; exertional dyspnea; labored breathing at rest; prolonged expiratory phase with wheezes and crackles; hypoxemia, hypercapnia, cyanosis Emphysema ("pink-puffer") - lack of cyanosis, use of accessory muscles (tripod position), pursed-lip breathing, airway collapse during expiration with trapping in alveoli and lungs causing "barrel chest"; increased breath sounds, diaphragmatic; fatigue to acute respiratory failure Chronic bronchitis ("blue-bloater") - cyanosis and fluid retention, hypoxemia stimulates red cell production - polycythemia, increased pulmonary vasoconstriction and elevation of pulmonary artery pressure increasing workload of right ventricle leading to right-side heart failure with peripheral edema (cor pulmonale) Diagnosis: - history and physical exam, pulmonary function tests, chest x-ray, laboratory tests Treatment: - management involves lifestyle, pharmacologic, and oxygen therapy in severe cases Lifestyle - smoking cessation; long-term pulmonary rehabilitation program to restore function to diaphragm, reduce work of breathing and improve gas exchange; avoidance of exposure to respiratory infections with influenza and pneumococcal vaccinations given per evidence-based practice Pharmacologic -Bronchodilators - long-acting beta2-agonists and inhaled anticholinergics (combination inhalers), oral theophylline when failure to respond to inhaled medicationsCorticosteroids - inhaled for acute exacerbations and COPD with asthma symptomsAntibiotics - exacerbations and viral respiratory infection to prevent secondary bacterial infection Oxygen (1-2 L/min) - significant hypoxemia (arterial Po2 <55 mmHg) - avoid increasing arterial Po2 >60 mmHg (suppresses ventilatory drive leading to hypoventilation and carbon dioxide retention)
Atelectasis Disease Card
Definition: - incomplete expansion of lung or portion of lung Etiology: - airway obstruction, lung compression, pleural effusion, increased recoil of lung due to loss of pulmonary surfactant: 1) primary or secondary of newborn 2) acquired - mucous plug in airway or external compression by fluid, tumor, mass, or exudate Clinical Manifestations: - tachypnea, tachycardia, dyspnea, cyanosis, hypoxemia, diminished chest expansion, absence of breath sounds, intercostal retractions Diagnosis: - history and physical examination findings of signs/symptoms; CXR, CT scan Treatment Goal: - reduce airway obstruction or lung compression and reinflate lung Treatment: - ambulation, deep breathing and body positioning to increase lung expansion, oxygen, bronchoscopy to remove obstruction
Community Acquired Pneumonia
Definition: - infection beginning outside the hospital or diagnosed with 48 hrs after admission to hospital in a person who has not resided in LTC facility for 14 days or more before hospitalization Cause: - bacterial or viral; most common S. pneumoniae Manifestations: - sudden chill, fever, cough, pleuritic pain, sputum with red/brown rusty color Diagnosis: - age, coexisting health problems, severity of illness, chest x-ray, infections in community, sputum for staining and culture, blood cultures for person requiring hospitalization Treatment: - empiric antibiotic therapy for individuals not requiring hospitalization Often, community-acquired pneumonia causative organism is the bacteria - Streptococcus pneumoniae - and referred to as pneumococcal pneumonia.
Rhinosinusitis Disease Card
Definition: - inflammation of the mucous membrane of the nasal passages and paranasal sinuses. Types include: acute bacterial - 5-7 days to 4 weeks subacute - 4-12 weeks chronic - >12 weeks recurrent - > 4 acute episodes in 12 months (episode of 7-10 days) Cause: - obstruction of ostia that drain sinuses, viral URI, allergic rhinitis, nasal polyps, barotrauma (swimming or diving), abuse of nasal decongestants; organisms include rhinovirus (most common), Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis Clinical Manifestations: - acute - facial pain, headache, purulent nasal discharge, decreased sense of smell, fever, pain on bending, maxillary pain, pain in teeth chronic - fullness in ears, postnasal drip, hoarseness, chronic cough, loss of taste/smell, headache Diagnosis: - history of preceding common cold, physical exam findings, transillumination (identify maxillary sinus involvement); CT for chronic; MRI for suspected neoplasm/ fungal infection Treatment: - antibacterial (bacterial cause), intranasal corticosteroids, mucolytic agents, symptom relief measures (saline nasal sprays or steam inhalations); surgery for removal of polyps or obstruction Complications: - edema of eyelids, orbital cellulitis, subperiosteal abscess formation, mastoiditis, encephalitis
Pleuritis Disease Card
Definition: - inflammation of the parietal pleura with pleuritic pain; also known as pleurisy Etiology: - may be due to viral or bacterial infection; secondary pleurisy often follows trauma, pneumonia, tuberculosis and neoplasm Clinical Manifestations: - unilateral and abrupt onset of pain made worse by coughing or deep breathing; tidal volumes small; increased shallow breathing to maintain minute volume; reflex splinting of chest muscles with lesser respiratory expansion Diagnosis: - history and physical examination; auscultation of the lungs may produce a squeaky, rubbing sound during inspiration Treatment: - identify and treat cause; symptomatic management with analgesics (NSAIDs), heat application, and support of chest movement to decrease pain
Hospital Acquired Pneumonia
Definition: - nosocomial lower respiratory tract infection not present or incubating on admission to hospital; develops more than 48 hours after admission Cause: - Pseudomonas aeroginosa, Staphylococcus aureus, Enterobacter, Klebsiella pneumoniae, Escherichia coli Risk factors - intubation and mechanical ventilation; compromised immune function, COPD, airway instrumentation (endotracheal intubation or tracheotomy; ventilator-associated pneumonia - develops 48 hours or more after intubation) Manifestations: - malaise, fever, chills, rigor, cough, dyspnea, chest pain; in ventilated patients - worsening oxygenation and increased tracheal secretions DiagnosisL - chest x-ray; sometimes bronchoscopy and/or blood cultures Treatment: - antibiotic based on organism sensitivity
Fungal Respiratory Illness Disease Card
Definition: - pathologic fungi cause a delayed cell-mediated hypersensitivity response of primary pulmonary lesions consisting of aggregates of macrophages containing the organism and similar lesions developing in lymph nodes that drain the area; lesions develop into granulomas with giant cells; can develop central necrosis and calcification Cause: - Types: Histoplasma capsulatum, Coccidionides immitis, Blastomyces dermatitidis- specific to region in the US Transmission: infectious spores enter body through respiratory system usually causing minor symptoms - immunocompromised display more serious symptoms Clinical Manifestations: 1) acute primary disease presents with minor, self-limited, flu-like signs/symptoms 2) chronic cavitary pulmonary disease - productive cough, fever, night sweats, weight loss 3) disseminated infection (acute fulminating infection more often occurring in very old, very young, immunocompromised) - high fever, generalized lymphadenopathy, hepatosplenomegaly, muscle wasting, anemia, leukopenia, thrombocytopenia, hoarseness, ulceration of mouth/tongue, nausea, vomiting, diarrhea, abdominal pain; complication of meningitis Diagnosis: - skin testing for pathogen; direct visualization of organism from tissue sections or sputum culture Treatment: - supportive, symptomatic; antifungal therapy for immunocompromised or progressive disease
Pneumothorax Disease Card
Definition: - presence of air in pleural space with partial or complete collapse of lung Etiology: 1) spontaneous - primary - due to rupture of air-filled bleb or blister on surface of lung or secondary - due to emphysema, asthma, TB, CF, sarcoidosis, bronchogenic carcinoma, metastatic pleural disease 2) traumatic - penetrating or nonpenetrating chest injury 3) tension - intrapleural pressure exceeds atmospheric pressure (air enters, but not able to leave pleural space) Clinical Manifestations: - increased, labored respirations with dyspnea, tachycardia, pleural pain, and asymmetrical chest movements, atelectasis Diagnosis: - CXR, CT scan, pulse oximetry, blood gas analysis Treatment: 1) small pneumothorax - observation and CXR monitoring 2) larger pneumothorax - needle aspiration or closed drainage with or without suction 3) tension pneumothorax - emergency needle or chest tube insertion
Common Cold Disease Card
Definition: - self-limited viral infection of upper respiratory tract, lasting approximately 7 days Cause: - rhinovirus, coronavirus, adenovirus, parainfluenza, respiratory syncytial virus (see table above); incubation period - 2-3 days; period of contagion - incubation and continuing 5-7 days after symptoms appear - What is the likely cause in winter & spring? parainfluenza virus, respiratory syncytial virus, coronaviruses, adenovirus Clinical Manifestations: - rhinorrhea, watery eyes, stuffy head, sore throat, sneezing, and fever, (initial sore, scratchy throat followed by profuse, watery rhinorrhea; nasal congestion; sneezing; cough; malaise; fatigue; headache; hoarseness; sinus congestion; myalgia; fever (in children) Diagnosis: - history and physical examination findings Treatment: - rest, analgesic/antipyretic drugs, antihistamine (dry secretions - may worsen cough), decongestants nasal spray or oral [Note: nasal sprays can cause rebound rhinitis; oral decongestants can cause systemic vasoconstriction with increase n BP - avoid use in HTN, CAD, DM, or hyperthyroidism) Complications: - infants and immunocompromised may develop pneumonia
Bronchiectasis Disease Card
Definition: - uncommon type of COPD characterized by permanent dilation of bronchi and bronchioles due to destruction of muscle and elastic supporting tissue by infection and inflammation Etiology: 1) Localized - caused by tumors, foreign bodies, mucous plugs producing atelectasis and infection 2) Generalized -- bilateral and affecting lower lobes due to inherited impairments of host or acquired disorders due to infectious organisms in airways (CF, immunodeficiency states, TB, fungal lung infection, lung abscess), or exposure to toxic gases Manifestations: - atelectasis, obstruction of smaller airways, diffuse bronchitis, recurrent bronchopulmonary infection, cough, production of foul-smelling purulent sputum, hemoptysis, dyspnea, cyanosis, clubbing of fingers, weight loss, anemia Diagnosis: - history and physical exam, chest x-ray, CT scan Treatment: - antibiotics, postural drainage, chest physical therapy, palliative or curative interventional bronchoscopy or surgery
What are the characteristics of hypercapnia?
Definition: - Pco2 >50 mmHg - increase in carbon dioxide content of arterial blood Etiology: - hypoventilation; ventilation-perfusion mismatching Manifestations: - elevated Pco2 produces decrease in pH and respiratory acidosis; compensatory mechanism resulting in increase in serum Hco3- levels and increase in pH levels Diagnosis: - few manifestations until Pco2 is markedly elevated with increase in pH levels Treatment Goal: - decrease work of breathing and improve ventilation-perfusion balance Treatment: - intermittent rest therapy (nocturnal negative-pressure ventilation); respiratory muscle retraining; mechanical ventilation for acute hypercapnia
What are the characteristics of hypoxemia?
Definition: - Po2 <60 mmHg - reduction in arterial PO2 with effects resulting from tissue hypoxia and compensatory mechanisms Etiology: - inadequate amount of O2 in air, disease of respiratory system, dysfunction of neurologic system, alterations in circulatory function Manifestations: - central and/or peripheral cyanosis, increased ventilation, pulmonary vasoconstriction, polycythemia Diagnosis: - clinical observation and PO2 level measurement - pulse oximetry, arterial blood gases Treatment: - correct cause and increase gradient for diffusion with supplemental O2 therapy Complications: - high flow rate of oxygen administration in COPD can depress ventilatory drive and cause oxygen toxicity with diffuse parenchymal lung injury; in healthy persons oxygen toxicity manifestations with cough, sore throat, substernal distress, nasal congestion, painful inspiration
Acute Respiratory Failure Disease Card
Definition: - failure in gas exchange due to either heart or lung failure, or both, due to condition that impairs ventilation, compromises matching of ventilation and perfusion, or impairs gas diffusion Etiology/Types: - Hypoxemic respiratory failure: 1) mismatching of ventilation and perfusion - areas of lungs ventilated but not perfused or areas are perused but not ventilated - often seen in advanced COPD 2) impaired diffusion - condition in which gas exchange between alveolar air and pulmonary blood impeded due to increase in distance for diffusion or decrease in permeability of surface area of respiratory membranes to movement of gases; causes severe hypoxemia, but no hypercapnia; occurring in interstitial lung disease, ALI/ARDS, pulmonary edema and pneumonia - Hypercapnic/hypoxemic respiratory failure: inability to maintain a level of alveolar ventilation sufficient to eliminate CO2 and keep arterial O2 levels within normal range; causes include depression of respiratory center (drug overdose, brain injury), disease of nerves supplying respiratory muscles (Guillain-Barre' syndrome or spinal cord injury), disorders of respiratory muscles (muscular dystrophy) exacerbation of lung disease (COPD), or thoracic cage disorders (severe scoliosis or crushed chest) Clinical Manifestations: - hypoxemia (cyanosis, restlessness, confusion, anxiety, delirium, fatigue, tachypnea, hypertension, cardiac arrhythmias, tremor) or hypercapnia (decreased cardiac contractility, decreased respiratory muscle contractility, arterial vasodilation, headache, increased CSF pressure, papilledema, carbon dioxide narcosis (somnolence, disorientation, coma), respiratory acidosis Diagnosis: - arterial Po2 <60 mmHg and/or arterial Pco2 >45 mmHg Treatment: - correct underlying problem, relieve hypoxemia and hypercapnia, establish airway (intubation), bronchodilating drugs, antibiotic, controlled oxygen therapy, mechanical ventilation
Pulmonary Hypertension Disease Card
Defintion/Etiology: - abnormal elevation of pressure within the pulmonary circulation; self-perpetuating causing secondary structural abnormalities of pulmonary vessels including smooth muscle hypertrophy and proliferation of vessel intima. Primary pulmonary arterial hypertension (PAH): persistent elevation in pulmonary artery pressure occurring in the absence of cardiopulmonary or other causes of pulmonary hypertension - primary idiopathic or familial Secondary pulmonary hypertension: increase in pulmonary pressures associated with other disease conditions, usually cardiac or pulmonary - elevation of pulmonary venous pressure from mitral valve disorders or left ventricular diastolic dysfunction - increased pulmonary blood flow from increased flow through left-to-right shunt in congenital heart disease - obstruction of pulmonary blood flow due to pulmonary thromboemboli - exposure of pulmonary vessels to hypoxemia causing vasoconstriction (COPD, sleep-disordered breathing, or chronic exposure to high altitudes) Cor pulmonale: right heart failure resulting from primary lung disease or pulmonary hypertension Clinical Manifestations: - few signs/symptoms in early stages until disease progresses - dyspnea initially while exercising then progressing to dyspnea at rest, fatigue, dizziness or syncope, chest pressure or pain, edema in lower extremities and later abdominal ascites, cyanosis, heart palpitations Diagnosis: - hard to diagnose early because it's not often detected by routine physical exam; testing is done to rule out other reasons for clinical manifestations including Doppler echocardiogram and transesophageal echocardiogram. Diagnostic right heart catheterization is most reliable way of diagnosing pulmonary hypertension by directly measuring pressure in the main pulmonary arteries and the right ventricle and the effect different medications have on pulmonary hypertension Treatment: - identify and treat underlying cause; vasodilators, endothelin receptor antagonists (reverse effects of endothelin that causes narrowing of blood vessels), calcium channel blockers, prophylactic anticoagulants, diuretics, oxygen; surgery - atrial septostomy (opening between left and right chambers of heart), transplantation.
Cystic Fibrosis Disease Card
Defintion/Etiology: - inherited disorder (mutation in CFTR gene) involving fluid secretion by exocrine glands in epithelial lining of respiratory, gastrointestinal and reproductive tracts causing chronic respiratory disease, exocrine deficiency, and elevation of sodium chloride in sweat Clinical Manifestations: - accumulation of viscid mucus in bronchi, impaired mucociliary clearance, lung infections (Pseudomonas aeruginosa, Burkholderia cepacia, Staphylococcus aureus, Haemophilus influenza); pancreatic dysfunction with steatorrhea, diarrhea, abdominal pain, and development of diabetes mellitus Diagnosis: - respiratory and GI manifestations; history of CF in sibling or positive newborn screening test; confirmatory sweat test; assessment of bioelectrical properties of respiratory epithelia; genetic test for CFTR gene mutations Treatment: - antibiotic therapy, pancreatic enzyme replacement, supplement vitamins and minerals, clinical trial with rhDNase (enzyme that breaks down degradation products), lung transplantation for end-stage lung disease Complications: - nasal polyps, sinus infections, pancreatitis, cholelithiasis
Pathologic fungi cause a ___ in which lesions develop in lungs into granulomas with giant cells.
Delayed cell-mediated hypersensitivity response
Persons with compromised immune function constitute a special concern in both categories of pneumonia - Why is this so? What are the causative organisms?
Pneumonia in immunocompromised persons remains a major source of morbidity and mortality. Although almost all types of microorganisms can cause pulmonary infection in immunocompromised persons, certain types of immunologic defects tend to favor certain types of infections. Defects in humoral immunity predispose to bacterial infections against which antibodies play an important role, whereas defects in cellular immunity predispose to infections caused by viruses, fungi, mycobacteria, and protozoa. Neutropenia and impaired granulocyte function, as occur in persons with leukemia or bone marrow depression as well as in persons undergoing chemotherapy, predispose to infections caused by S. aureus, Aspergillus, gram-negative bacilli, and Candida.
B. What is the most probable reason for the progression of Robbie's asthma in terms of the early- and late-phase responses?
Review the illustration of the mechanisms of early- and late-phase IgE-mediated bronchospasm. Respiratory tract infections, especially those caused by viruses, may produce their effects by causing epithelial damage and stimulating the production of IgE antibodies toward the viral antigens. In addition to precipitating an asthmatic attack, viral respiratory infections increase airway responsiveness to other asthma triggers that may persist for weeks beyond the original infection.
Scenario A: Robbie Smith is a 10-year-old, who is having an acute asthmatic attack, and is brought to the ED by his parents. The boy is observed to be sitting up and struggling to breathe. His breathing is accompanied by use of the accessory muscles, a weak cough, and audible wheezing sounds. His pulse s rapid and weak and both heart and breath sounds are distant on auscultation. His parents relate that his asthma began to worsen after he developed a "cold", and now he doesn't even get relief from his albuterol inhaler. A. Explain the changes in physiologic function underlying Robbie's signs and symptoms.
Review the illustration of the pathogenesis of bronchial asthma. During an asthma attack, the airways narrow because of bronchospasm, edema of bronchial mucosa, and mucus plugging. Expiration becomes prolonged because of progressive airway obstruction. Due to narrowed airway and ineffective gas exchange, wheezing is noted. During a prolonged attack, air becomes trapped behind the occluded and narrowed airways, causing hyperinflation of the lungs. As a result, more energy is needed to overcome the tension already present in the lungs, and the accessory muscles are used to maintain ventilation and gas exchange. This causes dyspnea and fatigue. Symptomatology of asthma is substantial. The physical signs of bronchial asthma vary with the severity of the attack.
Scenario A: A 62-year-old man with an 8-year history of chronic obstructive pulmonary disease (COPD) reports to his health care provider with complaints of increasing shortness of breath, ankle swelling, and a feeling of fullness in his upper abdomen. The expiratory phase of his respirations is prolonged, and expiratory wheezes and crackles are heard on auscultation. Her blood pressure is 160/90 mm Hg, his red blood cell count is 6.0 x 106 uL (normal is 4.2 to 5.4 x106 uL), his hematocrit is 65% (normal male value is 40%-50%), his arterial PO2 is 55 mm Hg, and his O2 saturation, which is 85% while he is resting, drops to 55% during walking exercise. A. Explain the physiologic mechanisms responsible for his edema, hypertension, and elevated red blood cell count.
Severe hypoxemia, in which levels fall below 55 mm Hg, causes reflex vasoconstriction of the pulmonary vessels and further impairment of gas exchange in the lung. It is more common in persons with the chronic bronchitis form of COPD. Hypoxemia also stimulates red blood cell production, causing an increase in RBC and hematocrit values. The increase in pulmonary vasoconstriction and subsequent elevation in pulmonary artery pressure further increase the work of the right ventricle. As a result, persons with COPD may develop right-sided heart failure with peripheral edema (i.e., cor pulmonale).
Ruth has a cold with nasal congestion. She has been using a nasal spray for the past week several times a day and states that her nasal congestion is worse. Why?
She has developed rebound congestion
Why may fungal infection sometimes be confused with primary tuberculosis?
The primary pulmonary lesions are formed by aggregates of macrophages stuffed with the pathological fungi that form granulomas with giant cells in the lungs as well as in lymph nodes that drain the area. The granulomas may develop central necrosis and calcification resembling the lesions that occur in primary tuberculosis.
You can let your child 'hold his breath' during a temper tantrum. Why?
Voluntary control is limited by the level of carbon dioxide in the blood. When the concentration or partial pressure of carbon dioxide (Paco2) in the blood rises, breathing resumes automatically - the choice to take a breath will not be in his control!
Scenario A: Mr. Ruiz is a migrant worker who has been in the US for 6 months. He has been doing odd jobs, one of which has been cleaning chicken houses. While he is waiting for official citizenship papers, he has been unable to obtain permanent housing. He went to the health department when he could not stop coughing. He has lost 10 pounds in the last month and just does not "feel well". A) What additional information would be helpful?
What is his country of origin? Does he speak/understand English? Where has he been living? Has he been exposed to any infectious organisms? What is his past medical history?
Primary Tuberculosis
What is primary TB? form of disease developing in previously unexposed, unsensitized person; inhalation of droplet nuclei containing tubercle bacillus - asymptomatic developing latent tuberculosis infection —T lymphocytes and macrophages surround organism in granulomas that limit spread - do not have active disease and cannot transmit organism - 5% develop progressive, primary TB with destruction of pulmonary tissue & spread to multiple sites within lung (young children, adults with HIV or other immunodeficiency disease) What are the complications? - Miliary tuberculosis - disseminated to other organs (brain, meninges, liver, kidney, bone marrow)
Secondary Tuberculosis
What is the definition? - reinfection from inhaled droplet nuclei or reactivation of previously healed primary lesion; occurs in those with impaired body defense mechanism What is the cause? - cell-mediated hypersensitivity reaction can be aggravating factor Clinical manifestations: cavitation; bronchial dissemination; anorexia, weight loss; dry to productive cough becoming purulent and sometimes blood-tinged; dyspnea, orthopnea
Staging of SCLC is determined by micrometastases described as ___ (unilateral hemithorax) or ___ (beyond boundaries)
limited; extensive
ratio of carbon dioxide produced to oxygen consumption
respiratory quotient