nyyun928 - respiratory

5. Case Study Question 5-26 refer to the following case study: Mr. S. is admitted with a medical diagnosis of emphysema with impending respiratory failure. He has the following arterial blood gas results: pH= 7.35, P02 = 60 mm Hg, PC02 = 47 mm Hg, and HC03= 35 mEq/liter.

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Case Study Questions 105-113 refer to the following case study: Ms. J is admitted to the intensive care unit (ICU) on a mechanical ventilator after a motor vehicle accident in which she was the driver. She wasn't wearing a seatbelt. She is a long-term smoker with a past history of bleb formation. A diagnosis of flail chest is made.

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Case Study Questions 119-124 refer to the following case study: Mrs. T, a 1-day postoperative patient, had a Bilroth I surgery for gastric ulcer. She has a nasogastric tube attached to intermittent low suction, which is draining bile-colored secretions. Respiratory assessment indicates decreased breath sounds with an increase in fremitus over the upper and middle lobes and a decrease in fremitus at the bases. Arterial blood gas values are pH, 7.44; PO2, 90 mm Hg; PCO2, 46 mm Hg; and HCO3, 32 mEq/liter. Chest X-ray demonstrates blunting of the costophrenic angles.

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Case Study Questions 125-132 refer to the following case study: Mrs. J is admitted to the intensive care unit (JCU) with a diagnosis of pulmonary embolism from deep vein thrombosis. A continuous heparin infusion is started.

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Case Study Questions 133-135 refer to the following case study: Mr T, an automobile mechanic overcome by emission fumes, was admitted with a diagnosis of carbon monoxide poising.

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Case Study Questions 27-42 refer to the following case study: Mr. D. is admitted to the intensive care unit (ICU) with status asthmaticus, including episodes of supraventricular tachycardia and hypertension. On admission his arterial blood gas results on O, therapy of 35% by Venturi mask are pH, 7.50; PO2, 104 mm Hg; PCO2, 25 mm Hg; and HCO3, 23 mEq/liter. At home, Mr. D.was taking theophylline and prednisone.

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Case Study Questions 56-65 refer to the following case study: Ms. F. is admitted to the intensive care unit (JCU) from a long-term care facility with a diagnosis of impending respiratory failure. She has had a decreased level of consciousness for 3 days and a chronic problem with thick mucus production.

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Case Study Questions 66-68 refer to the following case study: Mr. Z. undergoes an open-lung biopsy complicated by massive pulmonary hemorrhage. An open thoracotomy is performed to stop the bleeding, and the patient returns to the intensive care unit (ICU) on a mechanical ventilator, with a chest tube draining about 50 ml/hr of bright red blood Mr. Z. 's hemoglobin and hematocritare 8. 6 mg/dl and 29%, respectively. Ventilator settings are IMV of 10 breaths/minute, FIO2 of 40%, tidal volume of 700ml and PSV of 5 ems H2O.

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Case Study Questions 88-104 refer to the following case study: Mr. W, a postoperative GI patient, has returned from the operating room and has been placed on a mechanical ventilator. He was not weaned from the respirator in the recovery room because of longstanding cardiac and respiratory diseases. A chest X-ray reveals Kerley's B lines, especially in the hilar area. Arterial blood gas studies reveal a shift to the right of the oxyhemoglobin dissociation curve.

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Case Study Question 43-55 refer to the following case study Ms. B., a visitor in the cafeteria, suffers a cardiac arrest. As a member of the code team, you respond. Ms. B. is receiving cardiopulmonary resuscitation (CPR) with mouth-to-mouth resuscitation.

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70. An increasing alveolar-arterial oxygen gradient indicates: A. Pulmonary embolism B. Eupnea C. Dead space D. Shunting

An increasing alveolar-arterial oxygen gradient indicates pathologic shunting due to underventilated alveoli caused by atelectasis, pulmonary edema, or pneumonia. In most cases, physiologic shunting causes an alveolar-arterial oxygen gradient of about 10 mm Hg on room air. Alveolar-arterial oxygen gradient is measured after the patient has received oxygen therapy at 100% for 15 minutes to wash out all nitrogen from the alveoli, after which all that remains in the alveolus is oxygen, water vapor (47 mm Hg), and carbon dioxide. Alveolar oxygen is measured by subtracting water vapor and the measured PCO2 from atmospheric pressure (760 mm Hg), multiplying the result by the percentage of FIO2 the patient is receiving, then subtracting the measured PO2. The normal alveolar-arterial oxygen gradient on 100% oxygen is 30 to 50 mm Hg. Alveolar-arterial oxygen gradient is increased by uneven ventilation in relation to perfusion. In pulmonary embolism, perfusion is interrupted; thus, the alveolar-arterial oxygen gradient does not usually indicate pulmonary embolism. A small alveolar-arterial oxygen gradient is desired will occur in eupnea, or normal breathing. Increased dead space, as in emphysema, may result in an increased alveolar-arterial oxygen gradient through hypoventilation and hypercapnia without a compensatory increase in minute ventilation.

69. A high peak inspiratory pressure in a patient on a volume mechanical ventilator indicates that: A. Lung compliance is decreasing B. Lung compliance is increasing C. The patient is not receiving the full tidal volume D. The ventilator system is disconnected

Compliance helps determine lung expansibility; decreased compliance results in stiffened lungs that require more pressure to achieve the same ventilation. Peak inspiratory pressure is the amount necessary to deliver a set tidal volume in volume mechanical ventilator. In pressure ventilators, high inspiratory pressure causes a lower tidal volume to be delivered because the preset pressure is quickly reached causing CO2 retention. Because of this, pressure ventilators should not be used in patients at risk for decreased lung compliance. A decreasing alveolar-arterial oxygen gradient is a desired event; it will not be seen in decreased lung compliance.

53. Inspiratory pressure is measured on Ms. B. as part of her respiratory assessment. Inspiratory pressure is : A. Desirable if between 0 and -10 em H2O B. An indication of inspiratory muscle strength C. Not a criterion for weaning from a ventilator D. Not affected by the addition of positive end-expiratory pressure

Correct Answer - B Inspiratory pressure is an indication of inspiratory muscle strength. Measured by a pressure gauge, it is the amount of pressure needed to inflate the lungs and expand the thorax. The more negative the reading, the better the inspiratory effort. An inspiratory pressure lower than - 20 cm H2O meets the criteria for weaning from a mechanical ventilator. The addition of positive end-expiratory pressure improves both inspiratory and expiratory pressures. Inspiratory muscles can fatigue when the work of breathing increases, as in neuromuscular disease, malnutrition, decreased compliance, hypoxia, cardiac arrest, anemia, and diminished cardiac output.

67. The use of PSV of 5 ems H2O in this setting is utilized for which of the following reasons? A. To overcome resistance from ventilator tubing B. To increase functional residual capacity C. Weaning D. To decrease risk of barotrauma

Correct answer - A A low PSV of 5 ems H20 helps to reduce the workload of breathing during spontaneous breaths by overcoming the resistance to breathing caused by ventilatory tubing or small endotracheal tubes. Higher levels ofPSV are required to overcome increased work of breathing due to disease processes or for the purpose of weaning.

19. A mixed venous blood gas sample is drawn from the pulmonary artery catheter. A mixed venous PO2 of 35 mm Hg indicates: A. Adequate tissue perfusion B. Low cardiac output C. Hypoxemia D. Chronic acidosis

Correct answer - A A mixed venous PO2 of 35 mm Hg indicates adequate tissue perfusion (normal is 35 to 40 mm HG). This implies adequate ventilation and circulation. A low mixed venous P02 is due to ventilatory hypoxia (tissues extract their normal amount of oxygen, sending deoxygenated blood back to the right of the heart) or diminished cardiac output (blood flow is sluggish through the capillaries, allowing tissues to extract more than the normal amount of oxygen). Comparing the mixed venous sample with an arterial sample and determining cardiac output will indicate which problem is at fault. Blood gases, whether arterial or mixed venous, should always be interpreted in light of the patient's history and past blood gas readings to determine a chronic acidotic state.

34. Mr. D. has a history of extrinsic asthma. His status asthmaticus was most likely precipitated by: A. Hay fever B. Smoke C. Exercise D. Respiratory infection

Correct answer - A A patient with extrinsic asthma may have status asthmaticus precipitated by hay fever. Extrinsic asthma is caused by allergens (including ragweed, shellfish, and drugs, such as penicillin) that release histamines, leading to increased mucus production and bronchoconstriction. Intrinsic asthma is nonallergic; attacks are precipitated by smoke, exercise, respiratory infection, or emotional distress. These factors induce bronchial irritation or bronchoconstriction.

96. Which is not an advantage of a tracheostomy? A. It provides humidification to the airway B. It decreases dead space C. It bypasses narrowed airways D. It is useful for long-term airway management

Correct answer - A A tracheostomy does not provide humidification to the airway; it bypasses the upper airways where humidification occurs. Thus, humidification must always be provided artificially. A tracheostomy decreases dead space (the amount of tidal volume that does not take part in gas exchange), bypasses narrowed upper airways if laryngeal stenosis occurs, and proves effective in long-term airway management.

123. A medication used to correct this acid-base imbalance is: A. Acetazolamide B. Sodium bicarbonate C. Morphine sulfate D. Oxygen

Correct answer - A Acetazolamide (Diamox) is used to correct metabolic alkalosis, a condition characterized by excess bicarbonate. Bicarbonate is formed through the conversion of carbon dioxide and water with the assistance of the enzyme carbonic anhydrase. Acetazolamide is a potent carbonic anhydrase inhibitor, promoting diuresis and excretion of HCO3. Overuse of acetazolamide can lead to metabolic acidosis.

58. Acute respiratory failure in a patient with normal lung function is defi ned as: A. PCO2 above 50 mm Hg, PO2 below 60 mm Hg B. PCO2 above 40 mm Hg, PO2 below 40 mm Hg C. PCO2 below 60 mm Hg, PO2 below 70 mm Hg D. PCO2 below 20 mm Hg, PO2 below 60 mm Hg

Correct answer - A Acute respiratory failure in a patient with normal lung function defined as a PCO2 above 50 mm Hg and a PO2 below 60 mm Hg. Hypoxia occurs with carbon dioxide retention to produce acute respiratory failure; thus, the PO2 drops as the PCO2 rises . When the PO2 falls below 60 mm Hg, the percentage of saturated hemoglobin dramatically drops off. The patient with chronic obstructive pulmonary disease (COPD) must be closely assessed because he lives with chronic hypoxia and hypercapnia, typically presenting with a PCO2 of about 50 mm Hg and a PO2 of about 60 mm Hg.

97. Which principle is true regarding care of the patient with a tracheostomy? A. Humidification should always be used B. The inner cannula should be removed only for cleaning C. The cuff should always be kept inflated D. A trach eostomy should never be capped unless the patient can talk

Correct answer - A Always use humidification with a tracheostomy to prevent airway obstruction by dried secretions because a tracheostomy decreases the dead space that permits natural airway humidification. The inner cannula can be removed for cleaning and when capping a fenestrated tracheostomy tube. The cuff must be kept inflated only if the patient is on a mechanical ventilator or has no gag reflex. Otherwise, it may be deflated to increase airway size and prevent impinging on the esophagus. Ensuring that the patient can talk is unnecessary before capping a tracheostomy tube. Alternate means of communication, such as writing paper or an alphabet board, can suffice.

106. All of the following statements about blebs are true except: A. They can be found within the lung tissue B. They can cause a spontaneous pneumothorax C. They usually are a result of diffuse emphysema D. They are treated by surgical resection

Correct answer - A Blebs are pockets of air found within the pleural space, whereas bullae are found within lung tissue. When blebs rupture, they usually cause a spontaneous pneumothorax. Both blebs and bullae can result from chronic, long-standing air trapping, as seen in emphysema. When they become too large and impinge on normal lung tissue or cause multiple spontaneous pneumothoraxes, they are surgically resected.

110. Clamping of chest tube may cause: A. Tension pneumothorax B. Hemorrhage C. Cardiac tamponade D. Flail chest

Correct answer - A Clamping a chest tube may cause tension pneumothorax. Clamping prevents air or fluid escape from the pleural space and, if dangerous buildup occurs, tension pneumothorax can ensue. Therefore, the nurse should never clamp a chest tube for more than a few seconds, except in the event of tube disconnection or bottle breakage or when changing or removing the system.

CaseStudy Questions 69-86 continued from the previous case study: The day after surgery, Mr. Z. is still on a volume mechanical ventilator. Arterial blood gas analysis reveals hypoxemia without hypercapnia. Mr. Z. also has an increasing alveolar-arterial oxygen gradient and a high peak inspiratory pressure.

Correct answer - A Decreasing lung compliance in a patient on a volume mechanical ventilator may be determined by a high peak inspiratory pressure.

130. Pathophysiologic factors predisposing Mrs. J. to pulmonary embolism include all of the following except: A. Pre-existing pulmonary disease B. Hypercoagulable state C. Venous stasis D. Trauma to vascular walls

Correct answer - A Factors predisposing a patient to pulmonary embolism do not include pre-existing pulmonary disease. The three conditions, known as Virchow's triad, that: predispose one to pulmonary embolism are venous stasis, hypercoagulability, and trauma to vascular walls. Venous stasis is a result of bed rest and immobilization; most pulmonary embolisms are due to thrombus formation in the deep veins of the legs. Hypercoagulability occurs after surgery or pregnancy and with oral contraceptive use. Patients who need multiple intravenous insertions are at risk for trauma to vascular walls. Thus, many hospitalized patients are at risk for pulmonary embolism.

12. Which of the following parameters increases in the patient with emphysema? A. Functional residual capacity B. Tidal volume C. Inspiratory reserve volume D. Vital capacity

Correct answer - A Functional residual capacity increases in emphysema. Air trapping causes the alveoli to be distended with air, leaving more air in the lungs after expiration.

80. Hemodynamically, PEEP causes an increase in: A. Pulmonary vascular resistance B. Blood pressure c. Cardiac output D. Preload

Correct answer - A Hemodynamically, PEEP causes an increase in pulmonary vascular resistance, the resistance to forward blood flow in the pulmonary vasculature. Applying pressure to the thorax, as occurs in PEEP, increases the resistance. PEEP decreases venous return to the heart (preload), which in turn decreases cardiac output. A drop in cardiac output may decrease blood pressure.

98. Hemorrhage resulting from a tracheostomy is due to erosion of the: A. Innominate artery B. Subclavian artery C. Pulmonary artery D. Aorta

Correct answer - A Hemorrhage resulting from a tracheostomy is due to erosion of the innominate artery, also known as the brachiocephalic artery, which arises off the aortic arch and lies alongside the trachea to the right. Later, it divides into the right subclavian and right carotid arteries. Initial treatment of such a hemorrhage includes slowly pulling the tracheostomy tube out, with the cuff inflated, until the cuff is against the hemorrhage site and hemostasis can occur. In most cases, the artery must then be repaired surgically.

116. High frequency jet ventilation is indicated for the patient with a flail chest because this type of ventilation: A. Stabilizes the chest wall B. Improves oxygenation through increased tidal volumes C. Lengthens inspiratory time D. Promotes mobilization of secretions

Correct answer - A High frequency jet ventilation is indicated in patients with flail chest because it aids in stabilization of the chest wall. Since small tidal volumes are used in this mode of ventilation, chest excursion is minimized. This aids in preventing paradoxical respirations and allows the flail chest to heal.

16. Due to increased fatigue with loss of appetite, Mr. S. is started on an enteral tube feeding. Which type of diet is recommended for Mr. S? A. High fat, low carbohydrate B. High protein, high carbohydrate C. Low fat, high carbohydrate D. Low fat, high protein

Correct answer - A In clients with pulmonary disease and hypercapnea, a high fat, low carbohydrate diet is recommended. Carbon dioxide is produced from metabolism, especially from metabolism of carbohydrates, and may contribute to increase PCO2 levels. Fats cause less CO2 production than carbohydrates (and proteins as well) so a diet high in fat and low in carbohydrates is recommended in patients with COPD with CO2 retention.

38. Pancuronium bromide (Pavulon) is ordered to block Mr. D.'s respiratory efforts through paralysis of his respiratory muscles. The following medication should be available if it becomes necessary to reverse the effects of Pavulon: A. Neostigmine B. Atropine C. Narcan D. Tubocurarine

Correct answer - A Neostigmine, an anticholinesterase that prevents acetylcholine breakdown by its enzyme cholinesterase, thus improving impulse transmission, reverses the effects of pancuronium bromide (Pavulon). Atropine is not an antagonist of Pavulon but is administered with neostigmine to reduce the latter's side effects, such as decreased heart rate and increased bronchial secretions. Narcan is a narcotic antagonist that reverses the effects of morphine sulphate. Tubocurarine, also causing muscle paralysis, is an analog of Pavulon.

71. Which statement correctly described right-to-left shunting? A. Normal physiologic shunting causes the alveolar PO2 to drop from 104 to 95 mm Hg as it enters the arterial system B. Breathing 100% oxygen will correct pathologic shunting C. Normal physiologic shunting is 10% to 20% of cardiac output D. Normal physiologic shunting is a result of bronchial and thebesian arterial blood flow

Correct answer - A Normal physiologic shunting, about 2% to 5% of cardiac output, causes the alveolar PO2 to drop from 104 to 95 mm HG as it enters the arterial system. Venous return from the bronchial and thebesian venous circulation delivers deoxygenated blood to the pulmonary veins and left side of the heart, respectively. Pathologic shunting occurs in states of decreased ventilation, when blood perfusing underventilated regions returns poorly oxygenated to the arterial system. Breathing 100% oxygen will not correct pathologic shunting because this does not open alveoli and blood remains poorly oxygenated.

33. The physician orders propranolol (Inderal) to treat Mr. D.'s tachycardia and hypertension. The nurse questions the order; she knows propranolol is contraindicated in asthma because it may cause: A. Bronchospasm B. Atelectasis c. Pneumonia D. Apnea

Correct answer - A Propranolol (Interal) is contraindicated in asthma because it may cause bronchospasm. Propranolol blocks the beta-adrenergic effects of the sympathetic nervous system, such as increased heart rate and contractility, as well as bronchodilation. Newer beta-blocking agents, such as atenolol and metoprolol, are cardioselective, blocking the beta effects on the heart without inducing bronchoconstriction. These are considered safe, in low doses, for patients with asthma.

25. Mr. S. is taught pursed-lip breathing because it: A. Prevents air trapping B. Causes airway collapse C. Causes airway collapse D. Allows air to be quickly exhaled

Correct answer - A Pursed-lip breathing prevents air trapping and airway collapse. In patients with COPD, diseased airways easily collapse on expiration from increased intrathoracic pressure, causing air trapping in the alveoli. Pursed-lip breathing allows air to be exhaled more slowly because the lips partially obstruct the air. Airway pressure increases in relation to intrathoracic pressure, preventing airway collapse. Pursed-lip breathing does not affect surface tension, or surfactant.

86. A potential nursing diagnosis appropriate for the patient receiving inverse ratio ventilation is: A. Anxiety related to altered breathing patterns B. Impaired gas exchange related to insufficient tidal volume C. Ineffective airway clearance related to thick secretions D. Impaired gas exchange related to lung collapse

Correct answer - A Since breathing patterns are reversed in inverse ratio ventilation With more time being spent in inspiration than expiration, patient discomfort and anxiety may result from the inability to exhale when desired. Patients may complain of a feeling of fullness or bloated and sedation may be required to reduce discomfort and anxiety .

14. On physical assessment, the nurse would observe Mr. S. for all of the following systemic responses to chronic obstructive pulmonary disease (COPD) except: A. Splenomegaly B. Polycythemia C. Clubbing of the fingers D. Distended neck veins

Correct answer - A Systemic responses to chronic obstructive pulmonary disease do no include splenomegaly. Pulmonary hypertension results from long standing lung disease and can lead to right ventricular failure. Signs of right ventricular failure include distended neck veins and hepatomegaly. So that more oxygen can be carried to body tissues, polcythemia (increased production of red blood cells) occurs in response to chronic hypoxia. Clubbing of the fingers also results from chronic hypoxia, although the reason for this is unknown .

28. The correct arterial blood gas interpretation is: A. Uncompensated respiratory alkalosis B. Compensated respiratory alkalosis C. Uncompensated metabolic alkalosis D. Compensated metabolic alkalosis

Correct answer - A The arterial blood gas results indicate uncompensated respiratory alkalosis. The pH is elevated (normal is 7.35 to 7.45), indicating an alkalotic state. HCO3 is normal (22 to 26 mEq/liter), ruling out a metabolic component, either primary or compensatory. The PCO2 is decreased (normal is 35 to 45 mm Hg), indicating respiratory alkalosis.

50. The physician considers placing Ms. B. on the assist mode of the mechanical ventilator. How does this mode differ from IMV? A. Patient triggers respirator breaths at a set volume B. Respiratory rate is fixed C. Tidal volume varies D. Patient is allowed to generate an inspiratory effort

Correct answer - A The assist mode on a mechanical ventilator differs from IMV in that the patient triggers respiratory breaths at a set volume. Both allow the patient to generate an inspiratory effort. The assist mode allows the patient to set his own respiratory rate but, once initiated, establishes a set tidal volume Intermittent mandatory ventilation delivers a set amount of respiratory breaths with a fixed tidal volume but also allows the patient to spontaneously breathe with a varied tidal volume.

61. Evaluation of Ms. F.'s chest X-ray reveals consolidation of the lower lung segments. The nursing plan includes promotion of respiratory effort, postural drainage, and suctioning of retained secretions. The best position for proper respiratory excursion and promotion of the patient's respiratory effort is: A. Sitting in a chair B. Lying flat C. Left lateral decubitus D. Semi-Fowler's

Correct answer - A The best position for proper respiratory excursion is sitting in a chair, which allows for fuller diaphragm movement and more effective breathing and coughing while preventing atelectasis and muscle fatigue. Bed rest, including supine and semi-Fowler's positions, encourages physical in activity, which results in muscle weakness, atlectasis and retained secretions. Most patients with chronic respiratory insufficiency cannot tolerate prolonged bed rest, especially lying flat because they are in a state of general debilitation. The left lateral decubitus position may be used in the patient requiring bed rest, but only with the right lateral decubitus, prone and supine positions.

94. Sighs are not a component of Mr. W.'s respiratory settings. The effect of sighs can be achieved in mechanical ventilation by: A. Increasing the tidal volume B. Increasing the respiratory rate C. Instituting positive end-expiratory pressure D. Increasing the percentage of inspired oxygen

Correct answer - A The effect of sighs can be achieved in mechanical ventilation by increasing the tidal volume. A healthy person sighs every few minutes to reexpand alveoli when breathing at a normal tidal volume of 5 ml/kg. When mechanical ventilation was first instituted, therapy mimicked normal breathing. Later, it was found that increasing the tidal volume on mechanical ventilators to 10 to 15 ml/kg obviated the need for sighs.

3. An assessment of the patient would most likely reveal him to be: A. Hyperventilating B. Apneic C. Wheezing D. Cyanotic

Correct answer - A The patient compensating for metabolic acidosis would probably be hyperventilating. Metabolic acidosis results from decreased HCO3 causing a base deficit. Hyperventilation- the body's attempt to compensate for acidosis - decreases PC02 an acid. Apnea and severe wheezing would most likely lead to respiratory acidosis. Cyanosis primarily results from oxygen imbalance rather than acid-base imbalance.

52. ABG's one hour after the change to PSV 25 cms H2O and 35% FIO2, are pH 7.55, pO2 - 100, pCO2 = 24 and respiratory rate of 16 breaths/minute. Measured tidal volume is 1100 ml. Ms. B weighs 58 kg. Which action is recommended? A. Decrease PSV to reach a tidal volume of 800 ml B. Switch back to IMV C. Increase FIO2 to 40$ D. Change to assist mode of ventilation

Correct answer - A This patient is receiving too much tidal volume, causing respiratory alkalosis. Reducing the amount ofPSV will reduce her tidal volume and solve the problem. A patient weighing 58 kg. should have a desired tidal volume between 580- 870 ml (1 0-15 ml/kg). She is not hypoxic or tachypneic so does not require a rise in FI02 or the institution of IMV or assist mode of ventilation.

31. Which of the following best describes Venturi oxygen therapy? A. Accurate oxygen concentration occurs by mixing oxygen with entrained air B. Oxygen is conserved by rebreathing one-third of expired air from a reservoir bag C. Oxygen is delivered through tubing with two soft plastic tubes inserted into the nostrils D. 100% oxygen can be delivered

Correct answer - A Venturi oxygen therapy allows accurate oxygen concentration by mixing oxygen with entrained air; it cannot deliver oxygen concentrations higher than 40% to 50% depending on the mask, because the oxygen is diluted during mixing. Delivery of low concentrations of oxygen through Venturi oxygen therapy is especially useful in patients with chronic obstructive pulmonary disease (COPD). A partial rebreathing mask conserves oxygen through rebreathing one-third of expired air from a reservoir bag and can deliver up to 90% oxygen. Nasal cannulas, which deliver a low percentage of oxygen til rough two soft plastic tubes inserted into the nostrils, are useful to nose breathers and those with COPD.

32. The nurse auscultates Mr. D.'s lungs and hears vesicular breat II sounds. Vesicular breath sounds: A. Have a short expiration phase B. Are heard over the trachea C. Are a combination of bronchial and bronchovesicular sounds D. Suggest consolidation of lung tissue

Correct answer - A Vesicular breath sounds have a short expiration phase, are soft in nature, and are normally heard over most of the lung. Bronchial breath sounds have a long expiration phase, sound tubular, and are normally heard over the trachea. Bronchovesicular lung sounds are a combination of the above two and have equal inspiration and expiration phases. They are heard over large airways. Suspect consolidation, tumor, or atelectasis when bronchial or bronchovesicular breath sounds are heard where vesicular breath sounds are normally heard.

103. When capping a fenestrated, cuffed tracheostomy tube, you should: A. Deflate the cuff B. Tell the patient he won't be able to speak C. Provide oxygen via a tracheostomy collar D. Insert the inner cannula

Correct answer - A When capping a fenestrated, cuffed tracheostomy tube, you should deflate the cuff. The patient is no longer aerating through the tracheostomy when it is capped and must breathe around it. Deflating the cuff increases the airway's diameter, most likely preventing partial airway obstruction. The cap is inserted after removing the inner cannula. Oxygen must then be provided through a face mask or nasal cannula. The patient will then be able to speak because expired air passes through the larynx instead of the stoma.

82. An increasingly higher FI02 is required in Mr. Z. to prevent hypoxemia. Oxygen toxicity is a concern. Signs and symptoms of oxygen toxicity include all of the following except: A. Decreasing alveolar-arterial oxygen gradient B. Dyspnea C. Parasthesias in extremities D. Decreasing lung compliance

Correct answer - A An increasing alveolar-arterial oxygen gradient is a sign of oxygen toxicity, along with dyspnea, decreased lung compliance, and paresthesias in extremities. Long-term use of high percentages of oxygen reduces surfactant and destroys alveolar tissue. Oxygen toxicity can also result in central nervous system disturbances, such as paresthesias and seizures.

107. Two hours after her admission, you assess subcutaneous emphysema over Ms. J.'s left lateral chest. Subcutaneous emphysema is a complication of: A. Adult respiratory distress syndrome B. Pneumothorax C. Lung contusion D. Atelectasis

Correct answer - B A complication of pneumothorax, subcutaneous emphysema (also known as crepitus) is the accumulation of air in the subcutaneous portions of the skin. The air has escaped from the lung and may travel up the neck or down the abdomen. Treatment is aimed at removing the cause, and skin maybe incised to release air if it causes too much discomfort.

40. Two days later, the pancuronium bromide has been discontinued and Mr. D. is assessed for ability to be weaned. Which criterion best predicts successful weaning? A. Vital capacity of 10 ml/kg B. Minute ventilation of 9 l/min C. Negative inspiratory force of 10 cms H2O D. Tidal volume of 3 ml/kg

Correct answer - B A minute ventilation between 5-10 l/minute is predictive of weaning success. Other such parameters include a vital capacity of 10-15 ml/kg, a negative inspiratory force of 20- 30 ems H2O and a tidal volume of 4-5 ml/kg.

118. Which diagnosis is most appropriate for a patient on a ventilator like Ms. J. who feels she cannot control her environment? A. Social isolation B. Powerlessness C. Fear D. Self-esteem disturbance

Correct answer - B A patient on a ventilator who feels unable to control her environment is experiencing powerlessness. The critical care environment reinforces this feeling by curtailing the patient's activity, taking away familiar aspects of her environment, and frightening her about the tenuousness of her mortality. The patient's family may also feel powerless because they can see their loved one only during prescribed hours and cannot always get information about her condition. The nurse can alleviate this powerlessness by acting as a patient-family advocate- supplying needed information, allowing the patient to make some decisions about her care and environment, and involving the family in the patient's care.

134. Care of the patient with carbon monoxide poisoning includes: A. Continuous pulse oximetry monitoring B. Monitoring carbon monoxide levels by co-oximetry C. diuretic administration D. SvO2 monitoring

Correct answer - B Carboxyhemoglobin levels must be monitored in a patient with carbon monoxide poisoning. Co-oximetry measures this level, whereas standard blood gas analysis does not. The PO2 and O2 saturations will be normal in a person with carbon monoxide poisoning, making pulse oximetry and SvO2 monitoring unreliable. Diuretic administration has no benefit in the treatment of carbon monoxide poisoning.

122. Causes of Mrs. T. 's acid-base imbalance include all of the following except: A. Vomiting B. Diarrhea C. Diuretic treatment D. Corticosteroid administration

Correct answer - B Causes of metabolic alkalosis include vomiting, diuretic treatment, corticosteroid administration, Cushing's disease, aldosteronism, and nasogastric suction. These cause either gastric acid loss or increased renal acid excretion. With diarrhea, the patient loses large amount of bicarbonate, which results in metabolic acidosis.

18. Mr. S. is still breathing spontaneously without the aid of a mechanical ventilator. Which expected effect does spontaneous breathing have on hemodynamic waveforms? A. There is a increase in waveform pressures during inspiration B. There is a decrease in waveform pressures during inspiration C. There is a increase in waveform pressures during expiration D. There is a decrease in waveform pressures during expiration

Correct answer - B Due to negative inspiratory effort, there is a decrease in waveform pressures during inspiration in the spontaneously breathing patient. During positive pressure mechanical ventilation, there is a rise in waveform pressures during mechanically ventilated inspiration. It is recommended that waveform pressures be measure during end expiration in both the spontaneously breathing and ventilated patient in order to obtain correct values.

65. When the catheter passes the vocal cords during nasotracheal suctioning, the nurse should: A. Withdraw the catheter and apply suction for 20 seconds B. Continue passing the catheter until resistance is met; then withdraw the catheter and apply suction for 10 seconds C. Apply suction and continue passing the catheter until resistance is met; then withdraw the catheter and apply suction for 1 0 seconds D. Stop passing the catheter, apply suction 10 seconds, then withdraw the catheter

Correct answer - B During nasotracheal suctioning, the nurse should pass the catheter until resistance is met, withdraw the catheter, and apply suction for 10 seconds. If the catheter is just passing the vocal cords, it has not yet entered the trachea or bronchus and should be advanced until resistance is met. Never advance the catheter while suctioning or after meeting resistance because trauma to the airway can ensue. To prevent hypoxia or a choking sensation, never apply suction for more than 10 seconds in a conscious patient.

23. An electrolyte imbalance that Mr. S. would most likely develop as a result of chronic hypoxia is low: A. Sodium B. Chloride c. Bicarbonate D. Calcium

Correct answer - B Electrolyte imbalances resulting from chronic hypoxia include low chloride levels. In response to chronic respiratory acidosis, the kidney acts to correct this imbalance by retaining the base bicarbonate (in the form of sodium bicarbonate) in exchange for the acid chloride (in the form of sodium chloride). Also, increased ammonia (anacid) excretion occurs in the form of ammonium chloride. Thus, in chronic respiratory acidosis, elevated bicarbonate levels and low chloride levels will be noted. Sodium ions are reabosorbed as hydrogen ions are secreted. This maintains an appropriate electrical balance between the anions and cations in the tubular and extracellular fluid. Acidosis does not affect calcium levels.

112. Ms. J.'s chest tube is connected to a an underwater seal drainage system. Bubbling in the underwater seal area during expiration demonstrates that: A. The suction is working properly B. An air leak is present C. The lung has reexpanded D. Subcutaneous emphysema is present

Correct answer - B If the patient's chest tube is connected to an underwater seal drainage system, bubbling in the under water seal area during expiration demonstrates that an air leak exists and that the lung has still not fully reexpanded. Constant bubbling during inspiration and expiration in the suction control manometer indicates the application of suction. Subcutaneous emphysema is usually noted by palpating the patient's skin along the insertion site for crackles.

100. Mr. W. is weaned from the respirator. A fenestrated tracheostomy tube is inserted, and Mr. W. is receiving humidified 0 2 at 35%. Which statement accurately describes humidification in respiratory therapy? A. All gases hold the same amount of water vapor B. Mechanical ventilation does not allow for exhalation of water vapor C. Inspired dry gas is irritating because it cannot add water vapor once it enters the airway D. The colder the air, the more water vapor it can hold

Correct answer - B Mechanical ventilation, by nature a closed system, does not allow for exhalation of water vapor. This can lead to overhydration, hyponatremia, and weight gain. Factors that determine the amount of water vapor a gas can hold include the temperature, partial pressure, and solubility of the gas. Inspired dry gas is irritating because it pulls moisture from the airway to become fully saturated by the time it reaches the alveoli. The warmer a gas is, the more water vapor it can hold.

78. Most carbon dioxide in the blood is carried: A. In combination with hemoglobin B. As bicarbonate C. Dissolved in plasma D. As carbonic anhydrase

Correct answer - B Most carbon dioxide is carried in the blood as bicarbonate, through the conversion of carbon dioxide and water, with the assistant of the enzyme carbon anhydrase. From 60% to 70% of carbon dioxide is carried in this manner; 7% to 10% is physically dissolved as arterial PCO2. The remainder is carried in chemical combination with hemoglobin as carbaminohemoglobin.

43. Your first action is to attempt to ventilate Ms. B. with a manual resuscitator bag attached to portable oxygen. You base this action on the knowledge that mouth-to-mouth ventilation during CPR dlivers what percentage of oxygen? A. 9% B. 17% C. 21% D. 30%

Correct answer - B Mouth-to-mouth ventilation during cardiopulmonary resuscitation (CPR) delivers 17% oxygen (expired air contains more carbon dioxide than room air). Artificial ventilations must be performed correctly to deliver the optimal amount of oxygen; it is most important to open the airway through forward movement of the tongue. This can be accomplished by the head-tilt, chin-lift maneuver, which lifts the chin forward and hyperextends the head. Two ventilations, lasting 1 to 1-1/2 seconds, are performed after opening the airway and before beginning cardiac compressions in a pulseless victim. As soon as possible during CPR, the nurse should switch from mouth-to-mouth resuscitation to ventilation with a manual resuscitation bag attached to high-flow oxygen.

128. Which of the following statements about ventilation and perfusion is true? A. Normally, ventilation and perfusion are equally balanced throughout the lung B. Normal ventilation-perfusion ratio is 0.8:1 C. Perfusion scans are performed by having the patient inhale a radioactive substance D. Low ventilation-perfusion ratio occurs in pulmonary embolism

Correct answer - B Normally, the ventilation-perfusion ratio is 0.8: 1, with 4 liters/minute of ventilation of 5 liters/minute of perfusion. Because of gravity and pleural pressure, ventilation and perfusion are weakest at the apex and strongest at the base, although the difference is smaller for ventilation. Anything that interferes with ventilation, such a bronchospasm, lowers the ratio. Anything that interferes with perfusion, such as a pulmonary embolism, increases the ratio. A ventiIation-perfusion lung scan detects abnormalities. Ventilation scans are performed by having the patient inhale a radioactive substance; perfusion scans are performed by I.V. injection of a radioactive substance. A scanner then detects chest radiation.

113. Ms. J. begins to complain about puffiness of her face and neck. You assess the chest tube insertion site and palpate subcutaneous emphysema. This usually signifies that the: A. Patient needs thoracic surgery B. Chest tube needs repositioning c. Chest tube needs repositioning D. Chest tube needs stripping

Correct answer - B Progressive subcutaneous emphysema in the patient with a chest tube usually signifies that the chest tube needs repositioning. Subcutaneous emphysema is the collection of air under the skin; in the patient with a chest tube, this indicates that the lumen of the tube is not totally in the pleural space or that the seal around the exit of the chest tube from the pleural space is not tight enough. Progressive subcutaneous emphysema can be uncomfortable and unsightly for the patient.

27. Room air PO2 drops to 104 mm Hg in the alveolus because of the: A. Diffusion gradient B. Addition of water vapor and carbon dioxide C. Partial pressure of nitrogen D. Venous admixture from normal physiologic shunting

Correct answer - B Room air PO2 drops from 160mm Hg to 104mm Hg and the PN2 drops from 597 to 569 mm Hg in the alveolus to accommodate the addition of carbon dioxide and water vapor atmospheric air contains little of either. By the time air reaches the alveolus, it is totally humidified with water vapor, which has a partial pressure of 47 mm Hg. Alveolar air contains about 40 mm Hg of carbon dioxide. This addition of water vapor and carbon dioxide dilutes the partial pressures of oxygen and nitrogen because the total pressure cannot rise above 760 mm HG atmospheric pressure. The diffusion gradient and venous admixture from normal physiologic shunting cause the PO4 to drop from 104 to 95 mm Hg as it crosses from the alveolus into the arterial system.

22. If Mr. S. was found to have familial emphysema, this would be evidenced by a deficiency in: A. Surfactant B. Serum alpha antitrypsin C. Mucus production D. Lactic acid dehydrogenase

Correct answer - B Serum alpha antitrypsin is an enzyme inhibitor; its deficiency is thought to cause enzymal destruction of lung tissue. It is an autosomal recessive trait, usually noted in whites of European descent, and its appearance can signal familial emphysema. Symptoms can occur from the teenage years until early middle age. Familial emphysema accounts for only 1% to 2% of all people with chronic obstructive pulmonary disease.

5. The correct interpretation of the above arterial blood gas results 1 A. Compensated metabolic alkalosis B. Compensated respiratory acidosis C. Compensated respiratory alkalosis D. Compensated metabolic acidosis

Correct answer - B The PCO2 is elevated (normal is 35 to 45 mm Hg), a condition seen in primary respiratory acidosis and as a compensatory response to metabolic alkalosis. HCO3 is elevated (normal is 22 to 26 mEq/liter), a condition seen in primary metabolic alkalosis and as a compensatory response to respiratory acidosis. The pH determines the primary imbalance because when complete compensation occurs, the pH returns to near normal, never overcompensating. In this case, the pH is normal but tending toward acidosis. Thus, the correct interpretation is compensated respiratory acidosis.

125. The amount of Mrs. J. 's cardiac output that does not take part in gas exchange is called: A. Dead space B. Shunting C. Residual volume D. Stroke volume

Correct answer - B The amount of cardiac output that does not take part in gas exchange is called shunting. Physiologic shunting, normally 2% to 5% of the cardiac output, is a result of the venous return of the bronchial circulation to the pulmonary veins and thebesian venous return to the left side of the heart. Pathologic shunting occurs when ventilation to a portion of the lung ceases while perfusion continues. The most common causes of pathologic shunting are atelectasis, pneumonia, and pulmonary edema. Dead space is the portion of the tidal volume that does not participate in gas exchange. The residual volume is the volume of gas remaining in lungs after a maximal exhalation. The stroke volume is the amount of blood ejected from the left ventricle in one contraction.

9. All of the following are involuntary regulators of respiration except the: A. Hydrogen ion concentration B. Cortex C. Carbon dioxide level D. Oxygen level

Correct answer - B The cortex can be a voluntary, regulator of respiration; for example, a person willfully holds his breath or hyperventilates. The respiratory center of the brain lies in the medulla and the pons and contains three parts: the medulla rhythmicity center, which provides the basic rhythmicity for respiration; the apneustic center, which provides deep and prolonged inspirations when stimulated; and the pneumotaxic center, which inhibits inspiration, allowing for expiration. Carbon dioxide levels, hydrogen-ion concentration, and oxygen levels involuntarily regulate respiration.

44. After Ms. B. is successfully intubated, her breath sounds are assesed for possible right mainstem intubation. This is a concern because the the left main bronchus bifurcates from the trachea at a more acute angle than the right because ofthe position of the: A. Stomach B. Heart C. Thyroid gland D. Liver

Correct answer - B The left main bronchus bifurcates from the trachea at a more acute angle than the right because of the heart's position. Thus, an endotracheal tube enters the right main bronchus easier than the left. The heart's position also causes the left lung to be narrower than the right, with the left lung having only two lobes; the right has three. Because of the liver's position, the right hemidiaphragm is higher than the left, causing the right lung to be shorter. The thyroid gland and the stomach do not normally interfere with lung anatomy.

29. The most probable cause for Mr. D.'s acid-base imbalance is: A. Hypoventilation B. Hyperventilation C. Side effect of prednisone D. Theophyline toxicity

Correct answer - B The most probable cause is hyperventilation due to anxiety and bronchial constriction from asthma. Hypoventilation causes respiratory acidosis. A side effect of steroids, such as prednisone, is metabolic alkalosis. Side effects of theophylline toxicity do not include an acid-base imbalance.

1. At sea level, the partial pressure of oxygen in the air is: A. 760 mmHg B. 160 mmHg C. 105 mm Hg D. 40 mmHg

Correct answer - B The partial pressure of oxygen (PO2) in the air is 160 mm Hg. Atmospheric,or barometric, pressure is 760 mm Hg at sea level. The percentage of oxygen in room air is 21%; 21% of 760 mm Hg gives a room PO2 of 160 mm Hg. Alveolar PO2 is 105 mm Hg, and venous PO2, 40 mm Hg.

79. Before positive end-expiratory pressure (PEEP) is instituted for Mr. Z . he must be assessed for hypovolemia because PEEP can directly result in: A. Dysrhythmias B. A low cardiac output C. Hypoxia D. A high pulmonary capillary wedge pressure

Correct answer - B Use of positive end-expiratory pressure (PEEP) in a patient with hypovolemia will most likely result in a low cardiac output. Hypovolemia is a decrease in circulating blood volume. Applying PEEP increases intrathoracic pressure, which may compress the heart and blood vessels, especially the low-pressure venous system. Venous return to the heart decreases, further exacerbating the hypovolemia. Since venous return to the heart is a major determinant of cardiac output, a decreased venous return accompanied by hypovolemia is certain to result in a low cardiac output and a low pulmonary capillary wedge pressure. Once the cardiac output drops, hypoxia and dysrhythmias may occur as a result of decreased tissue perfusion.

11. Chest percussion of a patient with emphysema will reveal which type of sound? A. Resonant B. Hyperresonant C. Dull D. Flat

Correct answer - B In emphysema, the thorax and lungs will sound hyperresonant. Percussion helps determine if an area is filled with air, fluids, or solids, as fluids and solids replace air, the lung becomes dull to percussion. Normally, the lung is resonant to percussion but becomes hyperresonant upon air trapping, as seen in emphysema. The liver and the lung over pleural effusions will be dull to percussion.

8. Mr. S.' s respiratory control is most likely affected by a change in A. pH B. O2 saturation c. PO2 D. PCO2

Correct answer - C The patients respiratory control is most likely affected by a change in PO2. Normally, however, a change in PCO2, affects respiratory control. Carbon dioxide is a powerful respiratory stimulant - directly affecting respiratory neurons in the lungs and indirectly increasing hydrogen-ion concentration in the cerebrospinal fluid, which stimulates respiratory centers in the brain stem. People with chronically high PCO2 levels no longer respond to the PCO2 stimulus; to breathe, they must rely on their hypoxic drive, normally a weak stimulant to respiration. Low PO2 levels stimulate chemoreceptors of the carotid bodies and the aortic arch, causing increases in tidal volume and respiratory rate. Thus, raising the PO2 with O2 therapy in patients with chronic obstructive pulmonary disease (including emphysema and chronic bronchitis) will depress respiration and possibly result in respiratory arrest from hypoventilation. Through a change in hydrogen-ion concentration, pH has the second strongest effect on respiration. A pH below 7.41 stimulates respiration; a pH above 7.41 inhibits it O2 saturation, a measure of the percentage of hemoglobin saturated with O2 does not affect respiration because hemoglobin has no direct influence on the respiratory centers in the brain stem.

76. Pulmonary capillary leakage occurs in ARDS because of a decrease in: A. Cardiac output B. Blood pressure C. Colloid osmotic pressure D. Pulmonary capillary wedge pressure

Correct answer - C A decrease in the colloid osmotic pressure exerted by albumin and other proteins in the blood to keep fluid in the intravascular system may cause the pulmonary capillary leakage typical of ARDS. Normally, colloid osmotic pressure is 8 to 25 mm Hg higher than pulmonary capillary wedge pressure. If the wedge pressure rises or the colloid osmotic pressure drops, fluid leaks from the blood into then pulmonary interstitium, the hallmark of ARDS.

20. A mixed venous blood sample: A. Is drawn from the right atrial port of a pulmonary artery catheter B. Is a sample or oxygenated blood C. Reflects ventilation and circulation D. Replaces the need for arterial blood gas samples

Correct answer - C A mixed venous blood sample helps assess ventilation and circulation, whereas an arterial sample helps assess ventilation and the circulation to the extremity from which it was drawn. A mixed venous sample is drawn from the pulmonary artery (distal) port of a Swan Ganz catheter and is a sample of deoxygenated blood. It is not drawn from the right atrial (proximal) port because the interior vena caval venous return enters the low right atrium and might be excluded from a right atrial sampling. A mixed venous sample does not replace the need for an arterial sample; rather, it should be used with an arterial sample for total assessment of cardiopulmonary functioning.

83. To reduce the likelihood of oxygen toxicity, oxygen therapy that is to last longer than 48 hours should not exceed: A. 28% B. 35% C. 40% D. 50%

Correct answer - C A patient can develop oxygen toxicity after breathing 100% oxygen for 6 hours. To reduce the likelihood of oxygen toxicity, oxygen therapy should not exceed 40% if in use longer than 48 hours. This limitation can create a dilemma if the patient continues to have a low PO2 after being treated with high FIO2 although PEEP may resolve the low PO2 and reduce the high FIO2.

87. A common respiratory complication in septic shock is: A. Pneumothorax B. Tension pneumothorax C. Adult respiratory distress syndrome (ARDS) D. Cor pulmonale

Correct answer - C A patient in septic shock should be assessed for adult respiratory distress syndrome (ARDS). Capillary leakage, the cause of ARDS, occurs as the late phase of septic shock develops, causing a relative fluid volume deficit.

42. Thirty minutes after the initiation of weaning, which assessment Indicates potential weaning failure? A . O2 saturation drops from 98% to 94% B. The respiratory rate increases by 8 breaths/minute C. The heart rate rises by 24 beats/minute D. Minute ventilation is 7 1/minute

Correct answer - C A rise heart rate of 24 beats/minute may indicate weaning failure. Other mdicators are a drop in O saturation below 91%, a rise in minute ventilation above 10 I/minute and a rise in respiratory rate by 14 breaths/minute.

90. A shift to the right of Mr. W. 's oxyhemoglobin dissociation curve may be due to: A. Hypothermia B. Hypocarbia c. Acidosis D. Decreased 2,3-diphosphoglycerate

Correct answer - C A shift to the right of the oxyhemoglobin dissociation curve may be due to acidosis (see figure below). The oxyhemoglobin curve is a nonlinear, empirical description of the relationship between the partial pressure of oxygen in the blood and the actual amount of oxygen carried on the hemoglobin molecule (O2 saturation). At the upper flat end of the curve, large changes in PO2 are associated with small changes in O2 saturation, but along the lower steep portion of the curve, small changes in PO2 are associated with large changes in O2 saturation. A shift of the curve to the right allows more O2 to be released from hemoglobin for a give PO2, and is caused by acidosis, C02 retention, hyperthermia, and increased 2,3- diphosphoglycerate (2,3-DPG). A shift of the curve to the left impairs the release of oxygen from hemoglobin for a given PO2 and is caused by alkalosis, hypocarbia, hypothermia, and decreased 2,3 -DPG.

74. Which of the following statements about ARDS is true? A. It can be caused by hyperalbuminemia B. On autopsy, the diseased lung looks like the intestine C. It causes an increase in shunting D. It results in an increase in lung compliance

Correct answer - C ARDS causes increased shunting, the blood returning partially unoxygenated to the left side of the heart. The disease can be caused by hypoalbuminemia, in which osmotic pressure decreases, allowing fluid to leak in the pulmonary capillaries. This fluid leakage decreases surfactant, which stiffens the lung, thus decreasing lung compliance. On autopsy, the diseased lung looks like the liver, dark and tough; hence some people use the term "liver lung" when referring to ARDS.

72. A diagnosis of adult respiratory distress syndrome (ARDS) is made for Mr. Z. ARDS is characterized by all of the following except: A. High peak inspiratory pressures B. Large alveolar-arterial oxygen gradient C. Increased lung compliance D. Pulmonary edema

Correct answer - C Adult respiratory distress syndrome (ARDS) is characterized by high peak inspiratory pressures, large alveolar-arterial oxygen gradient, pulmonary edema, and decreased lung compliance. For an unknown reason, damage to the alveolocapillary membrane occurs, causing pulmonary capillary fluid leakage and results in a diffusion defect and pulmonary edema. This fluid leakage decreases surfactant, which causes a stiffening of the lung, or decreased compliance. Higher pressures must be generated to do the same work of breathing to overcome the lung stiffness. Hypoxia and atelectasis result.

99. Continuous positive airway pressure is ordered for Mr. W. This may be used to: A. Assist ventilations in an apneic patient B. Decrease lung compliance C. Wean a patient from positive end-expiratory pressure D. Reduce the need for a high FIO2

Correct answer - C Continuous positive airway pressure may be used to wean a patient on positive end-expiratory pressure (PEEP). The former uses positive pressure without machine-assisted breaths; the latter uses both Continuous positive airway pressure provides increased intrathoracic pressure during expiration of spontaneous breaths; therefore, it is contraindicated in apneic patients. As spontaneous breathing increases, machine-delivered breaths can be reduced and positive pressure can still be maintained during expiration to prevent alveolar collapse. However, extubating a patient who requires positive pressure is not recommended because hypoxia quickly returns. Using continuous positive airway pressure in a patient who requires high FI02 is also not recommended. Such a patient needs ventilatory assistance from PEEP.

135. All of the following are at increased risk of developing carbon monoxide poisoning except the person who: A. Smokes B. Has emphysema C. Has diabetes D. Has pre-existing cardiac disease

Correct answer - C Diabetes does not increase the risk of carbon monoxide poisoning. A smoker has an increased risk of carbon monoxide poisoning be cause he already has detectable levels of carbon monoxide in the blood from smoking. Diseases that interfere with the oxygen-carrying capacity of the blood, such as chronic lung or cardiac diseases, also increase the risk of carbon monoxide poisoning.

63. The correct patient position for draining the anterior lower lung segments is: A. Sitting upright or semireclining B. Lying face down with the hips elevated C. Lying on the back with the hips elevated D. Lying on the right side with the head elevated

Correct answer - C During postural drainage of the anterior lower lung segments, the correct patient position is supine, with the hips elevated. Sitting upright or semireclining drains the upper lobes. Lying flat down with the hips elevated drains the posterior lower lobes. Lying on the right side with the head elevated drains the left lobe. Sitting upright and leaning forward while the nurse performs cupping and clapping above the patient's clavicles drains the apical lung segment.

45. Ms. B. is successfully resuscitated from ventricular fibrillation and transported to the coronary care unit, where you are now her nurse. As part of your assessment, you measure the endotracheal tube cuff pressure because it should not exceed: A. Peak inspiratory pressure B. End expiratory pressure C. Tracheal capillary filling pressure D. Pulmonary capillary wedge pressure

Correct answer - C Endotracheal tube cuff pressure should not exceed tracheal capillary filling pressure, the amount necessary to maintain an adequate blood flow to the trachea- about 15 to 25 mm Hg. If cuff pressure exceeds tracheal capillary filling pressure, tracheal ischemia, necrosis, or tracheoesophageal fistula can occur. Peak inspiratory pressure is the maximal pressure necessary to generate an inspiratory effort. End expiratory pressure is the pressure in the alveolus at the end of expiration. Pulmonary capillary wedge pressure is the vascular pressure in the pulmonary capillary bed, a direct reflection of venous return to the heart.

35. A repeat blood gas analysis reveals hypercapnia. Hypercapnia associated with asthma occurs: A. During improvement of bronchospasm C. During severe airway obstruction D. As an early sign of an asthma attack

Correct answer - C Hypercapnia associated with asthma occurs during severe airway obstruction. Asthma is characterized by increased responsiveness of the airway to stimuli that cause airway constriction. In less severe asthma attacks, the PC02 level is low because of hyperventilation and the patient develops respiratory alkalosis. As airway obstruction increases, carbon dioxide is retained and respiratory acidosis ensues. Airway obstruction results from airway narrowing and mucous plugs; immediate therapy must be initiated to prevent the patient from developing respiratory arrest or status asthmaticus.

47. Later that shift, Ms. B. is awake and slightly restless. Arterial blood gases are drawn but cannot be sent to the laboratory immediately; they are placed on ice. What would happen if the samples are not placed on ice or analyzed immediately? A. The sample would clot B. The PCO2 level would decrease C. The PO2 level would decrease D. The HCO3 level would decrease

Correct answer - C If an arterial blood gas sample is not immediately analyzed or placed on ice, the PO2 level will decrease because blood will continue to use O2 and produce CO2. The falsely elevated PCO2 level will cause a falsely low pH reading. Placing the sample on ice retards this proces. HCO3 levels are usually not affected. Not using a heparinized syringe wilI cause the sample to clot.

131. Which statement is not true regarding pulmonary embolism? A. It is usually characterized by a sudden onset of dyspnea B. Chest X-rays are usually not diagnostic C. Oxygen administration will significantly reverse hypoxemia D. Therapy is aimed at preventing further emboli

Correct answer - C In pulmonary embolism, oxygen administration will not significantly reverse hypoxemia. The embolism blocks blood flow to the lungs, so hemoglobin cannot combine with oxygen. This is usually characterized by a sudden onset of dyspnea. Oxygen still diffuses across the alveolocapillary membrane, but the area is not perfused by blood and the blood returns, unoxygenated, to the left side of the heart. Because the defect is one of perfusion and not ventilation, chest X-rays are not usually diagnostic of pulmonary embolism. Treatment is aimed at preventing further pulmonary emboli through anticoagulation or surgical interruption, such as inferior caval umbrella or ligation. Newer treatment is under study to dissolve existing emboli through streptokinase administration.

115. A potential nursing diagnosis appropriate for the patient receiving high frequency jet ventilation is: A. Anxiety related to altered breathing patterns B. Impaired gas exchange related to insufficient tidal volume C. Ineffective airway clearance related to thick secretions D. Impaired gas exchange related to lung collapse

Correct answer - C Insufficient humidification may result in high frequency jet ventilation, resulting in thick secretions and possible mucus plugs. Frequent suctioning may be required. Amount and consistency of secretions should be frequently assessed.

92. The most common complication of intubation and mechanical ventilation is: A. Barotrauma B. Starvation C. Laryngeal edema D. Tracheoesophageal fistula

Correct answer - C Laryngeal edema is the most common complication of intubation and mechanical ventilation. Because the larynx is the narrowest part of the aiiWay, it is most at risk for edema. The patient must be closely watched in the postextubation period for signs of laryngeal edema especially stridor. Aggressive therapy to avoid reintubation includes humidification of the airway and sympathomimetic aerosol therapy. However, reintubation and eventual tracheostomy may be necessary. Barotrauma, or rupture of lung tissue, is a rare complication mostly associated with PEEP. Starvation is another infrequent compli cation indirectly related to mechanical ventilation; it occurs if a time lag exists between the institution of mechanical ventilation and the institution of an alternate means of proper nutrition. Tracheosophageal fistula is a rare, late complication that results from tracheal damage and may not occur until the postextubation period.

24. The most common cause of chronic obstructive pulmonary disease (COPD) is: A. Occupation B. Pollution C. Smoking D. Aging

Correct answer - C Most people with chronic obstructive pulmonary disease (COPD) are current or former smokers. Smoking reduces the activity of cilia and macrophages and induces bronchoconstriction. This increases sputum production and the risk of respiratory infection and decreases pulmonary functions. Other causes of COPD include aging, pollution, long-term occupational exposure to dust or fumes, allergies, heredity, and frequent respiratory infections.

49. Ms. B.'s problem would most likely be corrected by: A . Decreasing her IMV rate B. Increasing her Fl02 C. Decreasing her respiratory rate D. Increasing her tidal volume

Correct answer - C Ms. B.'s problem would most likely be corrected by decreasing her respiratory rate, usually through sedation. Because she was overriding the ventilator with a respiratory rate of 40 breaths/minute, decreasing her intermittent mandatory ventilation (IMV) rate would not make sense. Ms B.'s PO2 level was satisfactory, so increasing her FI02 would not resolve her condition. The same holds true for the tidal volume, which would increase the PO2 level and may further reduce the PCO2 level.

21. A typical change that you might expect to see on Mr. S.' ECG is: A. Complete right bundle branch block B. Left ventricular hypertrophy strain C. Peaked P waves D. Generalized ST elevation

Correct answer - C Peaked P waves are a common ECG change in patients with chronic obstructive pulmonary disease. Pulmonary hypertension stresses the right side of the heart, causing right atrial enlargement and position change. Incomplete right bundle branch block (RBBB) commonly occurs because of these rotational changes and right ventricular hypertrophy; complete RBBB is rare. Pulmonary hypertension does not affect the left side of the heart, so left ventricular hypertrophy will not be observed. ST and T wave changes are rare seen only with right ventricular hypertrophy in the early precordial leads.

81. A complication of PEEP may be: A. Atelectasis B. Liver infarction C. Pneumothorax D. Hypertension

Correct answer - C Pneumothorax is a complication of PEEP. Applying positive pressure may cause barotrauma to weakened lung tissue, causing tearing and resulting in a tension pneumothorax. Air builds up in the pleural space because it has no avenue of escape. This may reduce cardiac output or cause compression of the mediastinum, heart, or trachea. The goal of PEEP is to prevent alveolar collapse, which can occur in pulmonary edema, atelectasis, ARDS, and respiratory failure. Decreased venous return to the heart can lead to liver congestion, decreased cardiac output, and hypotension.

17. A pulmonary artery catheter is inserted into Mr. S. to document whether he has pulmonary hypertension. Hemodynamic changes resulting from pulmonary hypertension do not include an increase in: A. Right ventricular pressure B. Pulmonary artery pressure C. Pulmonary capillary wedge pressure D. Pulmonary vascular resistance

Correct answer - C Pulmonary capillary wedge pressure reflects functioning of the left side of the heart, which is not usually impaired in pulmonary hypertension. Pulmonary hypertension increases pulmonary vascular resistance, the resistance to forward flow through the pulmonary blood vessels. Pulmonary hypertension also impedes ejection of blood from the right side of the heart into the pulmonary circulation and is reflected by hemodynamic changes- increases in right atrial, right ventricular, and pulmonary artery pressures.

51. Instead, Ms. B. is placed on pressure support ventilation (PSV) of 25 cms s and 35% FIO2. An important assessment to monitor while Ms. B. is on PSV is: A. Peak inspiratory pressure B. Negative inspiratory force C. Mi ute ventilation D. For the development of auto-PEEP

Correct answer - C Since a patient does not receive a specific amount of tidal volume while on PSV, it is important to monitor minute ventilation and tidal volume during this mode of ventilation.

120. Sound is best conducted through: A. Air B. Water C. Solid material D. Both air and solid material

Correct answer - C Sound, as in fremitus, is best conducted through solid material, less through fluids, and least through air. Fremitus is increased when solid material replaces air in lung tissue, such as in pneumonia, atelectasis, tumors, and pulmonary fibrosis . Fremitus is decreased when fluid or increased air accumulation prevents sound transmission, such as in pleural effusions, emphysema, and pneumothorax In the normal lung, fremitus is felt as soft vibrations on speaking that diminish toward the lower lobes.

55. The sign of upper airway obstruction that Ms. B. should be assessed for after extubation is: A. Crackles B. Rhonchi c. Stridor D. Wheezing

Correct answer - C Stridor, the high-pitched crowing that is audible, palpable, or auscultated over the trachea during inspiration, is a sign of upper airway obstruction, usually indicating laryngeal edema. Crackles, rhonchi, and wheezing are signs of lower airway obstruction, Crackles are heard on inspiration in dependent areas of the lungs and usually indicate fluid in the alveoli . Rhonchi and wheezing occur when air passes through larger airways, such as the bronchi or bronchiole, that are narrowed by secretions or spasm. Rhonchi are low-pitched sounds, whereas wheezing has a much higher pitch.

37. Talking at the nurses' station, ventilatory alarms, and the continuous lighting of the critical care unit can cause Mr. D. to experience: A. Sensory monotony B. Sensory deprivation C. Sensory overload D, Sleep deprivation

Correct answer - C Talking at the nurses' station, ventilatory alarms, and continuous lighting of the critical care unit can cause the patient to experience sensory overload, a state that occurs from an increase in frequency of stimuli. Sensory deprivation is a decrease in such frequency. Sensory monotony, which can be either overload or deprivation, is simply monotonous stimuli: a windowless room or a continuous meaningless noise, such as the beeping of a heart monitor. Excessive noise or stimuli induce stress, depriving a compromised patient of much-needed sleep. The patient can become confused or hostile and may hallucinate. This response, along with medications that may alter perceptions, leads to ICU (intensive care unit) psychosis.

126. The area from the nares to the bronchioles is called the: A. Nasopharynx B. Oropharynx C. Anatomic dead space D. Residual volume

Correct answer - C The area from the nares to the bronchioles is called the anatomic dead space- the portion of the tidal volume that does not take part in gas exchange, which is the sole function of the alveoli. Normally, dead space is about one-third of the tidal volume. Underperfused or underventilated alveoli do not take part in gas exchange, thereby increasing dead space. Mechanical ventilatory tubing lengthens the airway and also increases dead space. The nasopharynx lies immediately behind the nasal cavity, and the oropharynx is the posterior of the mouth.

2. A patient in the intensive care unit has the following arterial blood gas results: pH= 7.31, PCO2 = 35 mm Hg, and HCO3 = 18 mEq/liter. What is the correct interpretation of these results? A. Uncompensated respiratory acidosis B. Compensated respiratory acidosis C. Uncompensated metabolic acidosis D. Compensated metabolic acidosis

Correct answer - C The arterial blood gas results indicate uncompensated metabolic acidosis. The pH of 7.31 (normal is 7.35 to 7.45) indicates acidosis. The HCO3 of 18 (normal range is 22 to 26 mEq/liter) reflects a metabolic imbalance. When either the PCO2 or the HCO3 value is abnormal and the pH also falls outside the normal range, the arterial blood gas result is considered uncompensated.

64. The correct patient position for nasotracheal suctioning is: A. Leaning forward with the chin on the chest B. Sitting up at a 45-degree angle, with the head turned toward the nares entered C. Sitting up at a 45-degree angle, with the head turned away from the nares entered D. Lying on the back with the head forward

Correct answer - C The correct patient position for nasotracheal suctioning is sitting at a 45-degree angle, with the head turned away from the nares entered. This position straightens the trachea, aligns the airway, and eases entry into the bronchus. Hyperextending the head may curl the catheter at the back of the throat, and flexing the head could cause the catheter to enter the esophagus. Having the patient cough opens the epiglottis and vocal cords and may facilitate entry into trachea.

73. The goal of treatment for ARDS is to: A. Increase PC02 elimination B. Decrease respiratory rate C. Increase functional residual capacity D. Increase tidal volume

Correct answer - C The goal of treatment for ARDS is to increase functional residual capacity, the volume of air remaining in the lungs at the end of a normal expiration. Such an increase forces collapsed alveoli to open, an effect usually achieved by instituting positive end-expiratory pressure. Increasing PC02 elimination, decreasing respiratory rate, and increasing tidal volume help reduce respiratory insufficiency but do not reverse ARDS. Damage to the alveolocapillary membrane impairs oxygen rather than carbon dioxide diffusion, because carbon dioxide is 20 times more soluble than oxygen.

89. The hilar area of the lung is the: A. Bifurcation of the bronchi B. Apex of the lung C. Mediastinal surface where the blood vessels and bronchi enter the lung D. Base of the lung above the diaphragm

Correct answer - C The mediastinal surface where the pulmonary blood vessels and the bronchi enter the lung is called the hilar area, or hilus. It is visible on chest X-ray as the area on either side of the sternum with clear, light vascular markings. The hilar area is also where the visceral pleural folds back to become the parietal pleura.

4. The most probable cause for the above arterial blood gas results is: A. Nasogastric suction B. Neuromuscular disease C. Diabetic ketoacidosis U. Anxiety

Correct answer - C The most probable cause for metabolic acidosis is diabetic ketoacidosis, a condition in which increased fat metabolism (resulting from impaired glucose utilization) causes a buildup of ketones. Other causes include lactic acidosis, starvation ketosis, ethylene glycol and methanol poisoning, renal failure, diarrhea, drainage of pancreatic juices, and ingestion of acidic drugs, as in aspirin overdose. Diarrhea and drainage of pancreatic juices, however, will result in a non-anion gap acidosis. Nasogastric suction drains hydrochloric acid, causing metabolic alkalosis . Neuromuscular disease causes hypoventilation, manifested by respiratory acidosis. Anxiety causes respirator alkalosis as a result of hyperventilation.

57. Nursing care of the patient in impending respiratory failure is aimed toward: A. Sedation to ensure rest B. Drawing of arterial blood gases C. Preventative measures D. Suctioning

Correct answer - C The patient in impending respiratory failure must be assessed to discover which preventative measures are needed. These measures may include opening the airway, suctioning, positioning, initiating aerosol therapy, and administering oxygen. Clinical findings, subjective information from the patient, arterial blood gas results, and chest X-rays may help in assessing the situation, but preventive care is the best way to avoid respiratory failure. Sedation, usually avoided It cause it can cause hypoventilation, may be necessary if mechanical ventilation is used.

68. Three hours after surgery, the chest tube stops draining. The most appropriate nursing action at this time is to: A. Increase the suction B. Call the physician to remove the chest tube C. Assess for subcutaneous emphysema D. Assess for tracheal deviation

Correct answer - D A chest tube should continue to drain for about 48 hours after surgery. If drainage stops in the immediate postoperative period, catheter occlusion has occurred. Fluid and air can build up in the pleural s\pace of the affected lung, causing a tension pneumothorax. Signs or a tension pneumothorax include tracheal deviation, which should be assessed for immediately; deviation of the cardiac structures to the unaffected side; and hypotension. Notify the physician promptly if the chest tube drainage stops in the immediate postoperative period.

36. Mr. D. is intubated and placed on a volume ventilator, which delivers a preset volume when the ventilator is triggered. An important disadvantage of this type of ventilator is that: A. It lacks adequate alarms B. Hypoventilation ensues if set pressures are reached early in the respiratory cycle C. Positive end-expiratory pressure cannot be initiated D.The set tidal volume is delivered even if high inspiratory pressures are generated

Correct answer - D A disadvantage of a volume ventilator is that it delivers the set tidal volume despite the possibility of generating high peak inspiratory pressures in the patient with decreased lung compliance. This increases the risk of barotrauma. Positive end-expiratory pressure can be initiated while the patient is on a volume ventilator. Some pressure ventilators lack an adequate alarm system. With all pressure ventilators, hypoventilation may ensue if set pressures are reached early, as in the patient with decreased lung compliance.

132. A pulmonary embolism can be definitively diagnosed by: A. Chest X-ray B. Arterial blood gas studies C. Lungscan D. Pulmonary angiogram

Correct answer - D A pulmonary embolism can be definitively diagnosed by a pulmonary angiogram. A chest X-ray is not diagnostic of pulmonary embolism because changes are rare and could be confused with those of an infection. Arterial blood gas analysis will show a decrease in PO2 which has many etiologies. Lung scans are helpful in the diagnosis of pulmonary embolism, but changes are similar to those of emphysema. Only pulmonary angiographic evidence of clots or embolism can definitively diagnose pulmonary embolism.

7.The physician orders administration of 50% oxygen by face mask to Mr. S. The nurse knows that this would most likely result in A. Resolution of the problem B. A decrease in the PCO2 C. Oxygen toxicity D. Hypoventilation

Correct answer - D Administration of 50% oxygen to the patient with chronic respiratory acidosis would probably cause hypoventilation. Patients with chronically high PCO2 levels fail to respond to the powerful respiratory stimulant effects of PCO2. Instead, they must rely on the less powerful respiratory stimulus of hypoxia, which increases tidal volume and respiratory rate. Administration of oxygen, especially 50% reduces hypoxia and the stimulus to breathe, causing hypoventilation and possibly apnea.

30. Associated symptoms Mr. D. would probably experience are: A. Headache and somnolence B. Nausea and vomiting C. Decreased ventilation and constricted pupils D. Numbness and tingling of extremities

Correct answer - D Associated symptoms likely for Mr. Dare numbness, tingling to extremities, and perioral tingling. Headache and somnolence are symptoms of metabolic acidosis, nausea and vomiting are associated with metabolic alkalosis. Decreased ventilation and constricted pupils are symptoms of respiratory acidosis from narcotic overdose.

26. As part of discharge teaching, the nurse cautions Mr. S. to avoid high altitudes. Which change in arterial blood gases would be expected if he travelled to such an area? A. PO2 would be higher B. pH would be lower C. PCO2 would be higher D. O2 saturation would be lower

Correct answer - D Atmospheric pressure decreases as altitude increases, so O2 saturation is usually lower at higher altitudes. Because the percentage of oxygen in the air remains the same, the partial pressure of oxygen also drops. This lowers arterial PO2 and, to a lesser extent, O2 saturation. Later, PCO2 levels drop - and the pH level may rise - as a result of hyperventilation, a response to hypoxia.

124. Blunting of the costophrenic angle on chest X-ray is most characteristic of: A. Pulmonary embolism B. Atelectasis c. Pneumothorax D. Pleural effusions

Correct answer - D Blunting on a chest X-ray of the costophrenic angle, the area where the diaphragm meets the rib cage at the lower, lateral aspects of the lung fields, is most characteristic of pleural effusions. Normally, this angle should be clearly visualized. Blunting indicates pleural effusions because fluid is gravity-dependent, accumulating in the lower lung fields when the patient sits upright. Pulmonary embolism does not usually produce changes on the chest X-ray, although changes in vascular markings occasionally occur. Pneumothorax may be suspected if a dark area appears between the ribs and the lung fields at the outer border of the lung fields, or if the trachea, mediastinum, and heart are shifted abnormally. Atelectasis may produce areas of increased density on chest X-ray, where white replaces black.

60. Which condition is associated with increased mucus production? A. Asthma B. Pulmonary emboli C. Emphysema D. Chronic bronchitis

Correct answer - D Chronic bronchitis is associated with increased mucus production. Inflammation and hypertrophy of the mucous glands produce the typical cough and sputum production associated with chronic bronchitis. Mucus production is uncommon in primary asthma or emphysema unless chronic bronchitis or respiratory infection accompanies it. Hemoptysis (expectoration ofblood) is a symptom of pulmonary emboli and chronic bronchitis.

15. Some of the physiologic changes in patients with COPD occur because chronic hypoxia causes: A. Decreased cardiac output B. Peripheral cyanosis C. Anemia D. Increased erythropoiesis

Correct answer - D Chronic hypoxia causes increased erythropoiesis, the stimulation of red blood cell production, to compensate for chronically low PO2 levels. The bone marrow is stimulated to produce more red blood cells, a condition known as secondary polycythemia. Chronic hypoxia also causes a compensatory increase in cardiac output. Central (not peripheral) cyanosis occurs in hypoxia. Peripheral cyanosis results from a lack of blood flow to an extremity. Anemia is important during acute hypoxic episodes because decreased red blood cell production reduces the blood's oxygen-carrying capacity, exacerbating hypoxia.

46. The endotracheal cuff requires 60 mm Hg of pressure to maintain an adequate air seal. What is the probable cause for this? A. Endotracheal tube is in the right mainstem bronchus B. Endotracheal tube has a leaky cuff C. Patient has tracheal stenosis D. Patient needs a larger endotracheal tube

Correct answer - D If the cuff pressure in an endotracheally intubated patient requires 60 mm Hg to maintain an adequate seal, the patient probably needs a larger endotracheal tube because the cuff is overinflated on one side of the trachea and cannot adequately seal the other side. Most tracheas are oval rather than circular. A large diameter endotracheal tube (7. 5 to 8 mm inner diameter for females and 8 mm or larger for males) should be inserted to ensure a proper seal. Cuff pressure does not reflect a right mainstem intubation. A leaky cuff registers low tracheal cuff pressures. High cuff pressure with a small amount of inserted air and adequate seal maintenance suggest tracheal stenosis.

85. The physician decides to initiate inverse ratio ventilation to improve Mr. Z. 's respiratory status. A common complication that must be assessed for is: A. Mucus plugs B. Atelectasis C. Pneumothorax D. Air trapping

Correct answer - D In inverse ratio ventilation, more time is spent in inspiration than expiration. A problem that may occur is air trapping, referred to as "auto-PEEP", which occurs if the next inspiration begins before the patient has completed expiration. Airway pressure should be monitored at the end of expiration by occluding the expiratory valve on the ventilator to determine the development of auto-PEEP.

88. Kerley's B lines on chest X-ray indicate: A. Pneumothorax B. Pulmonary emboli C. Emphysema D. Pulmonary edema

Correct answer - D Kerley's B lines on chest X-ray indicate pulmonary edema and mitral stenosis. Horizontal, linear shadows in the lower, peripheral lung fields, Kerley's B lines are thought to be caused by increased lymphatic drainage resulting from elevated pulmonary capillary wedge pressure. They appear most clearly during inspiration and usually disappear on resolution of pulmonary edema unless fibrosis has occurred. Vascular markings will not appear on the affected side of pneumothorax; a shift in the trachea and heart may occur. Chest X-rays are not usually diagnostic of pulmonary emboli. The chest X-ray of the patient with emphysema will reflect overinflation through a lowered diaphragm and flattened costophrenic angles.

62. Postural drainage should be used for: A. A patient with pneumonia who is 8 months pregnant B. A postoperative craniotomy patient C. A patient in the immediate postprandial period D. A patient receiving aerosol therapy

Correct answer - D Postural drainage should be used for the patient receiving aerosol therapy; the therapy loosens secretions, and postural drainage mobilizes them. To prevent nausea, vomiting, and aspiration, the nurse should never institute postural drainage immediately after the patient has eaten but should wait at least 1 hour. Certain patients are poor risks for postural drainage. Positioning the head lower than the body causes increased intracranial pressure, a damage to postoperative craniotomy patients. In advanced pregnancy, this position causes the fetus to move toward the lungs, impeding ventilation and possibly causing respiratory distress.

41. Which mode of ventilation is indicated for weaning? A. Assist control ventilation B. Inverse ratio ventilation C. High frequency jet ventilation D. Pressure support ventilation

Correct answer - D Pressure support ventilation is a mode of ventilation useful in the weaning process because it reduces airway resistance and the work of breathing. Spontaneous breaths are supported during inspiration. With a preset amount of pressure until a desired tidal volume is achieved . The amount of PSV can be decreased during weaning as the patient assumes more control over breathing.

59. The most common cause of airway obstruction is: A. Bronchospasm B. Aspiration C. Laryngeal edema D. Relaxation of the tongue

Correct answer - D Relaxation of the tongue is the most common cause of airway obstruction. This occurs in unconscious states, such as narcotic overdosage and neurologic disease, or as a result of muscle weakness secondary to neuromuscular disease. The tongue relaxes, falling back in the oral cavity and obstructing the airway. Hyperextending the neck with the patient in the supine position opens the airway and often returns spontaneous respirations in an apneic patient. Bronchospasm is a common cause of airway obstruction in patients with exacerbations of chronic obstructive pulmonary disease. Aspiration can obstruct the airway in comatose patients or in those who have lost the gag reflex. Laryngeal edema may cause airway obstruction in the postextubation period.

56. Early signs of impending respiratory failure include: A. Cyanosis B. Wheezing and rhonchi C. Intercostal and substernal retractions D. Tachycardia and restlessness

Correct answer - D Tachycardia from carbon dioxide retention is an early sign of impending respiratory failure. Other early signs include restlessness, confusion, headache, somnolence, and papilledema. Cyanosis wheezing, and intercostal retractions are late signs of respiratory failure and are not always present. For example, wheezing may occur only in bronchospasm, whereas cyanosis is a dependent characteristic that differs from patient to patient and from observer to observer.

6. This acid-base imbalance is a chronic condition because: A. The patient has had the same arterial blood gases since admission B. The PCO2 is elevated C. The HCO3 is elevated D. The pH is normal

Correct answer - D The acid-base imbalance can be a chronic condition if the pH is normal. This physiologic, homeostatic mechanism attempts to maintain a normal pH by altering the acid-base component not primarily affected. Thus, the body compensates for metabolic alkalosis or acidosis by altering the rate of carbon dioxide removal from the lungs through hypoventilation or hyperventilation, respectively. In respiratory alkalosis or acidosis, the body stimulates the kidneys to excrete or retain bicarbonate, respectively. The body never overcompensates, so the pH will tend toward the primary abnormality. Abnormal blood gas results that remain unchanged after admission do not necessarily indicate a chronic condition.

39. Which of the following may prolong the effects of neuromuscular blockade on Mr. D.? A. Hyperthermia B. Administration of penicillin C. Blood administration D. A history of myasthenia gravis

Correct answer - D The effects of neuromuscular blocking agents may be prolonged in patients with myasthenia gravis or hypothermia, and in those receiving large doses of aminoglycoside antibiotics. These agents interrupt impulses at the neuromuscular junction, where motor nerve meets muscle fiber. Patients with myasthenia gravis already have an impairment at the neuromuscular junction, due to accelerated breakdown of acetylcholine, which transmits the nervous impulses. Blood a elm i nistration has no effect on the excretion of neuromuscular blocking agents.

48. Ms. B. is overriding her intermittent mandatory ventilation (IMV) rate of 8 with a respiratory rate of 40 breaths/minute. Her tidal volume is 850 ml and FIO2 is 35%. Arterial blood gas value are as follows: pH= 754, PO2 = 80 mm Hg, PCO2 = 25 mm Hg, and HCO3 = 23 mEq/liter. Match her acid-base status with its cause A. Respiratory acidosis due to cardiac arrest B. Respiratory alkalosis due to cardiac arrest C. Respiratory acidosis due to hyperventilation D. Respiratory alkalosis du · lo hyperventilation

Correct answer - D The patient's pH is high (normal is 7.35 to 7.45) indicating an alkalotic state; HCO3 is normal (22 to 26 mEq/liter), ruling out a metabolic component; and PCO2 is low (normal is 35 to 45 mm Hg), indicating respiratory alkalosis. Respiratory alkalosis results from hyperventilation caused by nervousness, anxiety, pulmonary embolus, or too high respiratory setting on a mechanical ventilator. Too low a setting cause the patient to override the respirator with an increased respiratory rate and, along with sepsis and liver disease, may also cause respiratory alkalosis. Cardiac arrest usually results in a mixed respiratory and metabolic acidosis due to hypoventilation and lactic acidosis.

95. Mr. W. cannot be weaned from the respiratory, and a tracheostomy is scheduled because his vital capacity is below normal. The vital capacity is the amount of air: A. Breathed in and out for 1 minute B. Breathed in and out in one breath C. Remaining in the lungs after a maximal exhalation D. Maximally exhaled after a maximal inhalation

Correct answer - D Vital capacity is the amount of air that can be maximally exhaled after a maximal inhalation. It is decreased by conditions that reduce thoracic expansion, such as muscle weakness, pleural effusions, pneumothorax, incisional pain, and abdominal distention. Minute ventil ation is the amount of air breathed in and out in 1 minute; tidal volume is th e amount of air breathed in and out in one breath. Residual volume is the amount of air remaining in the lungs after a maximal exhalation.

108. The physician inserts a chest tube in Ms. J. When correctly placed, the lumen of the chest tube is situated in the: A. Intercostal space B. Intra-alveolar space C. Pericardia! space D. Pleural space

Correct answer - D When correctly placed, the lumen of a chest tube is situated in the pleural space, thus allowing for air or fluid drainage and lung reexpansion. Usually, the chest tubes pass through the intercostal spaces to reach the pleural space. If chest tubes were placed in the intra-alveolar space, they would be within the lung, which would, in essence, be a pneumothorax. If chest tubes are in the pericardial space, they would be situated in the lining of the heart.

84. Complications of oxygen therapy include: A. Pneumothorax B. Hyperventilation C. Atelectasis D. Anemia

Correct answer -C Atelectasis is a complication of oxygen therapy. When high percent ages of oxygen are delivered, the airways contain less nitrogen, a condition known as nitrogen washout. Subsequently, the alveolus contains only oxygen, carbon dioxide, and water vapor. If the air way becomes occluded by secretions, oxygen diffuses into the pulmonary capillary, leaving nothing in the alveolus, and it collapses.

75. ARDS is characterized by destruction of surfactant. Which of the following statements accurately describes surfactant? A. It increases surface tension as alveolar volume decreases B. Reduced surfactant increases compliance C. It allows alveoli to collapse and re-expand during respiration D. It is produced by alveolar epithelial cells

Correct answer -D Surfactant, produced by alveolar epithelial cells, alters surface tension with alveolar volume. As the volume in the alveolus decreases during expiration, surfactant concentrates and decreases surface tension, preventing alveolar collapse. During inspiration, surfactant spreads over a larger area, increasing surface tension. Reduced surfactant reduces compliance, stiffening the lung. This increases the work of breathing, creating hypoxia and respiratory acidosis, Atelectasis, ARDS, near-drowning, and oxygen toxicity are some causes of reduced surfactant.

119. An increase in fremitus may be noted: A. In atelectasis B. In pneumothorax C. In emphysema D. Over pleural effusions

Correct answer- A An increase in fremitus (the vibrations that reflect voice transmission through the lungs onto the chest wall, palpated by an examiner's hands when the patient speaks) may be noted in atelectasis.

10. The nurse performs a respiratory assessment on Mr. S. She observes his chest to be barrel-shaped. All of the following are true about barrel chest except: A. It can be a congenital deformity B. It is an increase in the anteroposterior diameter of the chest C. It is a response to air trapping in the lungs D. It can be a normal response to aging

Correct answer- A Barrel chest, usually a response to aging or increased air trapping, is an increase in anteroposterior chest diameter. Normally, the lateral chest diameter is larger than the anteroposterior chest diameter in adults, but the two arc equal in barrel chest. Congenital chest deformities include kyphosis, scoliosis, pigeon chest, and funnel chest.

77. Mr. Z. has hypoxemia without hypercapnia because carbon dioxide is: A. Much more soluble than oxygen B. Equally as soluble as oxygen C. Much less soluble than oxygen D. Retained because of obstructive processes

Correct answer- A Carbon dioxide is about 20 times more soluble than oxygen. As a result, if damage to the alveolocapillary membrane occurs, oxygen diffusion is more severely impaired than carbon dioxide diffusion. Gas solubility determines its rate of diffusion across the alveolocapillary membrane, a rate also affected by thickness and surface area of the membrane and pressure differences between the two sides of the membrane.

129. Which clinical finding is present in pulmonary embolism? A. Vesicular breath sounds over most of the lung B. Increased tactile fremitus C. Hyperresonance to percussion D. Pleural friction rub

Correct answer- A Clinical changes in lung assessment are characteristically vague in pulmonary embolism. Vesicular breath sounds heard over most of the lung are a normal finding. Pulmonary embolism is assessed through significant patient history and diagnostic procedures.

102. Mr. W. 's cyanosis is a result of: A. Unsaturated hemoglobin B. Acidosis C. C02 retention D. Physiologic shunting

Correct answer- A Cyanosis, a bluish tinge to the skin, is a result of unsaturated hemoglobin; poorly oxygenated blood is bluish purple. Cyanosis usually is not evident until the arterial oxygen saturation level drops to about 80% or unless the blood contains nonfunctional hemoglobin (as in methemglobinemia) or at least 5 mg of unsaturated hemoglobin per I00 mi. Cyanosis is a relatively late sign of hypoxia. Patients with anemia will not demonstrate cyanosis as a result of low hemoglobin levels.

121. Correct interpretation of Mrs. T. 's arterial blood gas results is: A. Compensated metabolic alkalosis B. Compensated respiratory alkalosis C. Uncompensated respiratory alkalosis D. Uncompensated metabolic alkalosis

Correct answer- A The acid-base imbalance is compensated metabolic alkalosis. The pH is normal, indicating a compensated state but tending toward the alkalotic state. The bicarbonate is high, matching the alkalosis and indicating that the primary event is metabolic. The PC02 is high, indicating compensatory respiratory acidosis.

91. 2,3-diphosphoglycerate: A. Is carried in plasma B. Is a metabolite of glucose C. Is decreased in anemia D. Impedes the dissociation of 0 2 from hemoglobin

Correct answer- B 2,3-DPG, a metabolite of glucose that is contained in the red blood cell, decreases the affinity of hemoglobin for oxygen, thus increasing oxygen uptake at the cellular level. In other words, 2,3-DPG shifts the oxyhemoglobin dissociation curve to the right. Increased 2,3-DPG levels occur in anemia and hypoxia, compensating for the tissue hypoxia created by these conditions.

133. The primary treatment for carbon monoxide poisoning is: A. Having the patient breathe into a paper bag B. Administering Mucomyst C. Administering 100% oxygen D. Suctioning

Correct answer- C Administration of 100% oxygen is the primary treatment of carbon monoxide poisoning. Carbon monoxide's affinity for hemoglobin is 200 times greater than oxygen's and quickly binds to it, forming carboxyhemoglobin. High percentages of oxygen speed the release of the carbon monoxide from the hemoglobin. Administering Mucomyst, a mucolytic, is useful in bronchitis and also reverses an acetaminophen overdose. Breathing into a paper bag assists in CO2 retention and is the treatment for hyperventilation caused by anxiety. Suctioning is helpful in clearing the airway of secretions.

101. During morning care, Mr. W. 's tracheostomy tube falls out of his trachea and he becomes cyanotic. Your action is to: A. Initiate mouth-to-stoma respiration B. Prepare for endotracheal intubation C. Reinsert the tube, using the obturator D. Call the physician to insert a new tracheostomy tube

Correct answer- C If your patient's tracheostomy tube falls out, reinsert it using the obturator. The obturator is a rounded-end stylet that prevents the blunt end of the tracheostomy tube from causing trauma to the trachea during insertion. This should always be kept near the patient's bedside in case of such an occurrence. After inserting the obturator into the tracheostomy tube, make sure the cuff is deflated, and then insert the tube through the stoma. Usually, insertion is easier if the patient's head is hyperextended.

66. The most appropriate nursing action at this point would be to notify Mr. Z. 's physician in order to: A. Start a blood transfusion B. Prepare the patient to return to surgery C. Suggest an autotransfusion D. Prepare the patient for a second chest tube insertion

Correct answer- C Immediately after an open thoracotomy, bloody drainage from the chest tube at 50 to 100 ml/hr is common. An autotransfusion would return lost blood to the patient, preventing hypovolemia from hemorrhage. An autotransfusion is possible if sterile blood is collected, as from chest drainage systems, and the procedure helps prevent risks of infection or blood incompatibilities than can occur with donated blood.

105. In a flail chest, which of the following occurs during expiration? A. The affected side becomes depressed B. The mediastinum shifts to the unaffected side C. The flail portion bulges out D. Negative pressure decreases on th e affected side

Correct answer- C In a flail chest, the flail portion bulges out during expiration, pulling the mediastinum toward the affected side. This depresses ventilation and cardiac performance. During inspiration, air is sucked in from the flail portion because of the negative intrathoracic pressure depressing it, shifting the mediastinum to the unaffected side.

109. Which of the following statements about chest tube therapy is accurate? A. Chest tubes should be stripped toward the patient B. In three-bottle suction, the first bottle is the water-seal bottle C. The length of the glass tube below the water surface of the suction-control bottle determines the amount of suction D. Oscillation of the underwater seal fluid with ventilation indicates lung reexpansion

Correct answer- C In chest tube therapy, the length of the glass tube below the water surface of the suction-control bottle determines the amount of suction. Usually, this length is between 10 to 20 em. Each centimeter the glass tube is submerged equals 1 em of suction. Chest tubes should not be routinely stripped. If there is an obstruction by a blood clot, however, the chest tube should always be stripped away from the patient to prevent obstruction of the tubes by blood clots. In three-bottle suction, the first bottle is the drainage bottle, the second is the water-seal bottle, and the third is the suction-control bottle. Oscillation of the underwater seal fluid with ventilation indicates that-the lung has not yet reexpanded.

114. The physician places Ms. J. on high-frequency ventilation. Which statement accurately describes this type of ventilation? A. Tidal volumes are 5 to 10 ml/kg B. Gas exchange occurs through osmosis C. Respiratory rates are 100 to 200 breaths/minute D. The low tidal volume increases atelectasis

Correct answer- C In high-frequency jet ventilation, respiratory rates are 100 to 200 breaths/minute. Under low pressure, small jets of entrained air enter the airway through an additional catheter or port on the endotracheal tube. This ventilation method, which enhances diffusion of oxygen and carbon dioxide across the alveolocapillary membrane, is useful in atelectasis and ARDS, presumably because it protects surfactant. Low tidal volumes of 2.5 to 3.5 ml/kg help prevent the barotrauma and decreased cardiac output associated with PEEP.

54. The next day Ms. B. is extubated. After extubation, Ms. B. is assessed for signs of upper airway obstruction, a concern because the narrowest part of the airway is the: A. Trachea B. Nares c. Larynx D. Bronchus

Correct answer- C The narrowest part of the airway is the larynx, specifically the vocal cords in adults and the cricoid cartilage in children. This eliminates the need for cuffed endotracheal tubes in children because the cricoid cartilage, the only complete ring of cartilage, provides a seal for the tube. Because of its narrowness, irritation or trauma to the layrnx can cause edema and airway obstruction, a true respiratory emergency. A sign oflaryngeal edema is stridor, inspiratory crowing that can be audible, palpated, or auscultated over the neck.

117. Which assessment is difficult for the nurse caring for a patient receiving high frequency jet ventilation? A. Arterial blood gas interpretation B. Pulse and blood pressure C. Respiratory rate D. Lung sounds

Correct answer- D Because of the constant flow of gas and small tidal volumes produced, lung sounds are difficult to assess in the patient receiving high frequency jet ventilation. Use of the manual resuscitation bag to augment lung sounds may be necessary.

93. The low pressure alarm on Mr. W. 's ventilator is triggered. You cannot find a disconnection in the system. Your next action is to: A. Bypass the alarm B. Suction the patient C. Reset the alarm limits D. Manually aerate the patient until the cause is determined

Correct answer- D If a mechanical ventilator's low pressure alarm is triggered and you have checked the system for a disconnection, your next action should be to aerate the patient manually until the cause is determined. A low-pressure alarm indicates that the patient is disconnected from the ventilator and is not receiving the desired tidal volume. In many cases, the disconnection is not readily apparent; manual aeration prevents hypoxia until the problem has been rectified. A high-pressure alarm indicates rising pressures within the system from water obstructing the tubing, secretions obstructing the airway, or decreased lung compliance. Never bypass the alarm or reset the alarm limits.

111. Which assessment would be made on the affected side if the above complication occurred in Ms. J.? A. Dull to percussion B. Increased fremitus C. Tracheal deviation toward the affected side D. No adventitious breath sounds

Correct answer- D No adventitious breath sounds are present on the affected side in a tension pneumothorax because the lung has collapsed and no air movement occurs. The trachea may deviate to the unaffected side because of air buildup in the affected pleura. Because the pleura is filled with air, the affected side of hyperresonant to percussion with decreased fremitus, breath sounds, and heart sounds. Other symptoms include pleuritic chest pain, dyspnea, and hemoptysis.

104. You determine that Mr. W. has Cheyne-Stokes respirations. Which of the following is not true regarding this type of breathing? A. It is characterized by alternation periods of hyperventilation and apnea B. It is normal during sleep in children and the elderly C. It is due to changing carbon dioxide levels in the blood D. It is commonly seen in patients with chronic obstructive pulmonary disease

Correct answer- D Patients with chronic obstructive pulmonary disease usually do not develop Cheyne-Stokes respirations, which are characterized by alternating periods of hyperventilation and apnea. They are thought to be due to changing carbon dioxide levels in the blood. As respirations increase, carbon dioxide levels decrease, which suppresses the respiratory center's drive to breathe. Then, as respirations decrease, carbon dioxide levels increase, causing hyperventilation and further perpetuating the cycle. Cheyne-Stokes respirations are normal during sleep in children and the elderly. They are also seen in congestive heart failure and brain damage.

127. Which of the following statements about the pulmonary circulatory system is true? A. Five percent of the cardiac output is found in the pulmonary circulatory system at any time B. Hypoxia causes a decrease in pulmonary vascular tone C. Blood flow to the lung is greater at the apex than at the base D. The average diameter of a pulmonary capillary is equal to the average diameter of an erythrocyte

Correct answer- D The average diameter of a pulmonary capillary is equal to the average diameter of an erythrocyte, about 8 to 10 microns. Thus, the red blood cell must actually squeeze through the capillary, in effect touching the capillary wall. This increases the rapidity of oxygen and carbon dioxide diffusion across the alveolocapillary membrane. 10% and 20% of the cardiac output (about 1 liter) is in the pulmonary circulatory system at any one time, although only about 100 ml is in the pulmonary capillaries. Hypoxia increases pulmonary vascular tone, right ventricular pressures, pulmonary vascular resistance, and cardiac output. Because of the effects of gravity, blood flow is greater at the base of the lungs than at the apex.

13. The volume of gas remaining in the lungs after normal expiration is the: A. Functional residual capacity B. Residual volume C. Expiratory reserve volume D. Forced vital capacity

Functional residual capacity is the volume of air remaining in the lungs after a normal expiration. It is a combination of the expiratory reserve volume (maximal exhalation after tidal volume is expired) and residual volume (volume of air remaining in the lungs after maximal exhalation). Functional residual capacity cannot be easily measured at the bedside because residual volume cannot be directly measured by a spirometer. However, functional residual capacity can be measured, if necessary, by body plethysmography and helium dilution. Forced vital capacity is a maximal exhalation after a maximal inhalation.