CNST Chapter 23: Oxygen Therapy

The nurse is caring for several patients who require oxygen therapy. The nurse anticipates an order for noninvasive positive-pressure ventilation (NIPPV) for the patients with which diagnoses? (Select all that apply.) a. Pulmonary edema b. Obstructive sleep apnea c. Stroke with dysphagia d. Congestive heart failure

A, B, D In the cardiac patient, noninvasive positive-pressure ventilation (NIPPV) reduces pulmonary edema because the increased alveolar pressure forces interstitial fluid out of the lungs and back into the pulmonary circulation. In patients who retain carbon dioxide, such as with obstructive sleep apnea, NIPPV keeps the airway open and prevents upper airway collapse. In selected patients, such as those with postpolio syndrome and other neuromuscular diseases, congestive heart failure, sleep disorders, and pulmonary diseases, NIPPV is often the treatment of choice in supporting ventilation without the hazards associated with endotracheal intubation. NIPPV is contraindicated in patients at high risk for aspiration, as after a stroke with dysphagia.

The nurse is reviewing lab results for a patient with hypoxemia. The nurse is aware that which of the following results may worsen the patient's hypoxemia? (Select all that apply.) a. Low sodium levels b. Low hemoglobin levels c. Increased blood pH d. Decreased blood pH

B, C Hypoxemia is a deficiency of arterial blood oxygen. Decreased hemoglobin levels reduce the amount of oxygen transported to the cells. Acidemia (decreased blood pH) increases the ability of hemoglobin to release oxygen to the tissues. Alkalemia (increased blood pH) decreases the ability of hemoglobin to release oxygen to the tissues.

The patient is on mechanical ventilation. Which actions by the nurse are appropriate? (Select all that apply.) a. Keep the patient in a supine position. b. Note and mark the level of the endotracheal (ET) tube at the lips or nares. c. Have suction equipment available for immediate use. d. Perform mouth care at least twice daily.

B, C The patient should be positioned with the head of bed elevated 30 to 45 degrees to reduce gastric reflux, thereby decreasing the risk for aspiration and ventilator-associated pneumonia. Note and mark the level of the endotracheal (ET) tube at the lips or nares. This provides a baseline for depth of tube placement and ensures that the tube is not too close to the carina or in the right main-stem bronchus. Set up suction equipment, including oral suctioning, to provide airway care and suctioning as needed of the ET or tracheostomy tube, to prevent plugging of the airway, and to reduce the risk for infection. Perform mouth care at least 4 times per 24 hours. Use a toothbrush and a solution such as chlorhexidine, which is effective in reducing oral bacteria and the risk for ventilator-associated pneumonia.

The nurse is caring for several patients receiving oxygen by various delivery systems. Which assessment finding by the nurse indicates proper use of the oxygen device? a. No mist is noted in a face tent. b. The reservoir of the rebreathing mask collapses on inhalation. c. The flow rate is between 1 and 6 L/min for a nasal cannula. d. The flow rate for an oxygen hood is set at 3 L/min.

C The nasal cannula is used with an oxygen flow rate of 1 to 6 L/min. The face tent provides high humidity, and mist is expected. The reservoir of the rebreathing mask remains partially inflated when operating effectively to avoid rebreathing of carbon dioxide. The flow rate for an oxygen hood may be 5 L/min or more to prevent carbon dioxide (CO2) narcosis.

A patient is admitted to the emergency department following a motor vehicle accident. The patient is unconscious and has a broken jaw, a broken nose, and facial lacerations. The patient's breath sounds are diminished, and the health care provider suspects atelectasis. Frequent suctioning is required to clear the airway. Oxygen saturation levels range from 70% to 75%. The nurse recognizes that this patient most likely will have which type of ventilatory device ordered? a. Continuous positive airway pressure (CPAP) b. Bi-level positive airway pressure (BiPAP) c. Nasal cannula d. Mechanical ventilation

D Noninvasive ventilation, including CPAP and BiPAP, is contraindicated in cardiac or respiratory arrest, nonrespiratory organ failure, facial surgery or trauma, inability to protect the airway and/or high risk for aspiration, and inability to clear secretions. A nasal cannula cannot be used with nasal obstruction from a broken nose.

The nurse is caring for a patient on mechanical ventilation. The nurse determines that the endotracheal tube is properly placed by which assessment? a. Auscultating both lungs and watching the rise and fall of both sides of the chest b. Monitoring and comparing the blood pressure in both arms c. Observing and measuring inspiratory and expiratory rates d. Checking the settings on the ventilator and the low-pressure and high-pressure alarm settings

A Verify placement of the endotracheal tube by auscultating the lungs and assessing chest wall symmetry. This ensures that the tube has not migrated into the right main-stem bronchus. Many factors can cause blood pressure fluctuations and fluctuations in respiratory rate. Always assess the patient first. Once the patient is determined to be safe, the settings for the ventilator alarm can be checked as well.

The nurse is assessing a patient for hypoxia and observes a bluish discoloration in the following areas. Which areas indicate hypoxia? (Select all that apply.) a. Oral mucosa b. Conjunctiva of the eye c. Around the lips d. On the nail beds

A, B, C Cyanosis caused by hypoxia is observed in the oral mucosa, in the conjunctiva of the eye, and around the lips, known as circumoral cyanosis. Nail bed cyanosis may be caused by peripheral vascular disease or cold temperatures.

The patient is placed on mechanical ventilation. After the initial settings have been applied, the nurse should watch for which of the following complications? (Select all that apply.) a. Signs of decreased cardiac output b. Tension pneumothorax c. Pneumonia d. Failure to wean

A, B, C Multiple complications are associated with positive-pressure ventilation: decreased cardiac output, aspiration, tension pneumothorax, bronchospasm, laryngeal trauma, sinusitis, and ventilator-associated pneumonia. Failure to wean is not a major factor in starting the use of a ventilator; however, as the length of time needed for mechanical ventilation increases, the risk for failure to wean from the ventilator is increased.

The nurse is checking the oxygen flow rate on several patients. All flowmeters are set at 2 L/min. The nurse should question this flow rate for which delivery system(s)? (Select all that apply.) a. Nasal cannula b. Simple face mask c. Oxymizer d. Venturi mask

B, D Flow rates for a nasal cannula are 1 to 6 L/min, and flow rates for an oxymizer are 1 to 15 L/min, so 2 L/min is appropriate for either device. Flow rates for a simple face mask are 5 to 8 L/min to prevent rebreathing of CO2. Flow rates for a Venturi mask are 4 to 12 L/min, and a specific rate is necessary to deliver a specific FiO2.

A patient on mechanical ventilation has an FiO2 setting of 38%. The nurse is reviewing arterial blood gas results and pulse oximetry readings. The nurse is aware that the desired level of oxygen is which of the following? a. PaO2 greater than 90 mm Hg b. SpO2 greater than 60% c. PaO2 greater than 60 mm Hg d. SpO2 greater than 95%

C A patient on mechanical ventilation ideally has an FiO2 setting less than 40% to maintain PaO2 levels greater than 60 mm Hg and SpO2 levels greater than 90%.

A patient with a tracheostomy tube has an order for oxygen. Which action by the nurse is appropriate? a. Apply sterile gloves to connect the oxygen to the tracheostomy tube. b. Check the oxygen tubing frequently to make sure water is present in the tubing. c. Attach the T tube to a humidified oxygen source. d. Monitor the response to oxygen with hourly arterial blood gas levels.

C The T tube connects an oxygen source to an artificial airway such as a tracheostomy tube. Humidification is necessary because the artificial airway bypasses the normal humidification process of the nose and mouth. Clean gloves, not sterile gloves, are used to connect oxygen to the artificial airway. Fluid should be drained from the tubing so that it does not provide a medium for bacterial growth. Hourly arterial blood gases (ABGs) are not the standard for monitoring patients with artificial airways and oxygen.

A patient is planning to perform incentive spirometry after abdominal surgery. The nurse should encourage the patient to do which of the following? a. Get comfortable in a semi-reclined position. b. Inhale as deeply as possible and then exhale into the incentive spirometry device. c. Hold the breath for at least 3 seconds before exhaling. d. Exhale as quickly as possible.

C The patient should hold his breath for at least 3 seconds after inhalation. The patient should be positioned in the most erect position (e.g., high-Fowler's position), if tolerated. This promotes optimal lung expansion during respiratory maneuvers. The patient should exhale completely through the mouth and place the lips around the mouthpiece, and then he should take a slow, deep breath, hold it for at least 3 seconds, and exhale normally.

A patient has been using continuous positive airway pressure (CPAP), and now the health care provider is recommending bi-level positive airway pressure (BiPAP). The patient is asking the nurse to explain the difference again. Which response is appropriate? a. "CPAP maintains a set positive airway pressure during inspiration only." b. "CPAP opens the airways during inspiration and allows them to close during expiration." c. "BiPAP maintains a set pressure that is the same for inspiration and expiration." d. "BiPAP delivers sufficient expiratory pressure to keep the airways open."

D BiPAP uses two modes of pressure: one for inspiration and one for expiration. During expiration, BiPAP delivers sufficient pressure to keep the airways open. CPAP maintains a set positive airway pressure during inspiration and expiration. It keeps the airways open and prevents upper airway collapse.

The ________, also called a Briggs adaptor, connects an oxygen source to an artificial airway such as an endotracheal tube.

T tube The T tube, also called a Briggs adaptor, is a T-shaped device with a 15-mm (3/5-inch) connection that connects an oxygen source to an artificial airway such as an endotracheal (ET) tube or tracheostomy.

A patient with pneumonia is receiving supplemental oxygen. Which assessment finding(s) by the nurse should be reported as an early indication of hypoxia? a. Cyanosis around the lips and oral mucosa b. Anxiety and restlessness c. Decrease in the level of consciousness d. Decreased blood pressure and respiratory rate

B Anxiety, confusion, and restlessness are early signs of hypoxia. Cyanosis around the lips and mouth is a sign of hypoxia, but it is a late sign. Decreased level of consciousness, decreased respiratory rate, and decreased blood pressure are also late signs of hypoxia. The respiratory rate will increase as the body attempts to compensate for the decreased level of oxygen. As hypoxia worsens, the respiratory rate may decline. During early stages of hypoxia, blood pressure is elevated unless the condition is caused by shock.

A patient will be using a nasal cannula continuously to deliver oxygen at home, and the nurse is instructing the patient and family about important safety guidelines. Which of the following should be included in the teaching plan? (Select all that apply.) a. Smoking is allowed if it is not done in the same room in which the oxygen device is placed. b. If you feel short of breath, increase your oxygen by 2 to 3 L per minute. c. Avoid using an electric razor. d. Keep the oxygen tank at least 5 feet away from the stove.

C, D Items that create a spark such as an electric razor should not be used while a nasal cannula is in use. Oxygen delivery systems should be at least 5 feet from any heat source. No smoking is allowed on the premises. Oxygen is a medication. Increasing the oxygen liter flow for shortness of breath is similar to doubling heart, asthma, or other medications.

The nurse is teaching a patient with asthma how to measure peak expiratory flow rate (PEFR). What should be included in the teaching plan? (Select all that apply.) a. Assume a recumbent position before measuring PEFR. b. Take a deep breath in, exhale, then place the mouthpiece in the mouth and form a firm seal with the lips. c. After placing the mouthpiece in the mouth, blow out as hard and as fast as possible through the mouth in only one single breath. d. Measure PEFR 3 times and record the highest number.

C, D To measure PEFR, the patient should be standing. If the patient is unable to stand, high-Fowler's position or any other position that promotes optimum lung expansion should be used. The patient should take in a deep breath, place the mouthpiece in the mouth, and form a tight seal. Then the patient should blow out as hard and as fast as possible through the mouth in only one single breath. Two additional measurements are taken, and the highest number is recorded.

The nurse is caring for a patient on a mechanical ventilator and the low-pressure alarm sounds. Which action by the nurse is most appropriate? a. Assess for secretions in the airway and suction the patient. b. Administer a sedative to the patient to prevent coughing. c. Assess the endotracheal tube cuff to make sure it is deflated. d. Check the ventilator tubing and reconnect if disconnected.

The low-pressure alarm sounds when the ventilator has no resistance to inflating the lung. The patient may be disconnected from the ventilator, or a leak may have developed in the ventilator circuit. The high-pressure alarm sounds when the ventilator has met resistance to delivery of the tidal volume. This may result from coughing, increased secretions, or biting on the endotracheal tube. The cuff of the endotracheal tube is inflated to create a seal for positive-pressure ventilation. A cuff that is leaking could cause the low-pressure alarm to sound.

A condition in which oxygen is insufficient to meet the metabolic demands of the tissues and cells is known as __________________.

hypoxia Hypoxia is a condition in which oxygen is insufficient to meet the metabolic demands of the tissues and cells.

In noninvasive ventilation, ________________ keeps the terminal airways (alveoli) partially inflated, reducing the risk for atelectasis.

positive airway pressure Continuous positive airway pressure keeps the alveoli partially inflated, reducing the risk for atelectasis; if atelectasis has occurred, positive pressure assists in reinflation.

The amount of air inspired and expired with each breath while a patient is on mechanical ventilation is known as the ________________.

tidal volume (TV) tidal volume The tidal volume, the amount of air per breath, is usually set by the patient's ideal body weight (5 to 8 mL/kg).

A curved oxygen-delivery device with an adjustable strap that fits around the patient's neck is known as a _______________.

tracheostomy (trach) collar tracheostomy collar trach collar A tracheostomy collar is a curved device with an adjustable strap that fits around the patient's neck.

The nurse is caring for several patients postoperatively following abdominal surgery. Which patient will benefit the least from the use of incentive spirometry? a. Middle-aged male with a history of smoking since high school b. Elderly female with type 2 diabetes c. Middle-aged female with a history of chronic respiratory disease d. Adolescent female with atelectasis

B Incentive spirometry (IS) assists the patient in deep breathing. It is used most often following abdominal or thoracic surgery to help reduce the incidence of postoperative pulmonary atelectasis. It is especially beneficial in patients with a history of smoking, pneumonia, chronic respiratory disease, or atelectasis.

A patient with a nasal cannula at 5 L/min has skin irritation around the nares and complains of a dry mouth and nose. Which action by the student nurse should be questioned by the nursing instructor? a. Using humidification b. Applying petroleum-based gel to the nares c. Providing frequent oral care d. Asking the physician for an order for sterile nasal saline

B Petroleum-based gel should not be used around oxygen because it is flammable. If the oxygen flow rate is greater than 4 L/min, humidification should be used. Frequent oral care and sterile nasal saline will help when there is drying of the nasal and oral mucosa.

A patient is admitted with a diagnosis of chronic obstructive pulmonary disease (COPD) and the health care provider orders bi-level positive airway pressure (BiPAP). Which action by the nurse is appropriate? a. Set the initial bi-level positive airway pressure (BiPAP) settings at 4 to 8 cm H2O for inspiration and expiration. b. Draw arterial blood gas (ABG) levels after the first hour. c. Make sure the mask does not have quick-release straps. d. Set the initial BiPAP settings at 4 to 10 cm H2O for inspiration and at 10 to 15 cm H2O for expiration.

B When bi-level positive airway pressure (BiPAP) is initiated, especially in patients with underlying chronic obstructive pulmonary disease (COPD), it is important to obtain arterial blood gas (ABG) levels after the first hour and then per agency policy (usually every 2 to 6 hours) during the first day because these patients may retain carbon dioxide. BiPAP initial settings are 10 to 15 cm H2O for inspiratory pressure and 4 to 10 cm H2O for expiratory pressure. It is imperative that the mask have quick-release straps. In the case of an emergency (e.g., vomiting and respiratory arrest), quick-release straps allow the mask to be removed quickly. This system also allows the patient to remove the mask quickly as needed.

A patient in respiratory distress enters the emergency department. The patient denies a history of chronic obstructive pulmonary disease (COPD). The nurse anticipates an order for oxygen delivered by which method to achieve the highest possible concentration of oxygen? a. Simple face mask at 15 L/min b. Nonrebreathing face mask at 15 L/min c. Venturi mask at 15 L/min d. Oxygen tent at 15 L/min

B When used as a nonrebreather, the face mask with a reservoir bag delivers 60% to 90% oxygen at 15 L/min. The simple face mask delivers oxygen concentrations from 40% to 60% when set at 5 to 8 L/min. It is not used at 15 L/min. A Venturi mask delivers oxygen concentrations from 24% to 60% when set at 4 to 12 L/min. It is not used at 15 L/min. An oxygen tent is usually for pediatric use and delivers up to 50% oxygen concentration at 10 to 15 L/min.

A patient diagnosed with chronic obstructive pulmonary disease (COPD) is on oxygen therapy at 3 L per nasal cannula. Which assessment finding should alert the nurse to a potential problem with this patient? a. Respiratory rate of 26 b. Low carbon dioxide levels c. Arterial oxygen saturation level of 99% d. Lower oxygen saturation levels at night than during the day

C In the patient with COPD, high levels of oxygen can extinguish the stimulus to breathe. In the individual with healthy lungs, the chemoreceptors are sensitive to small changes in carbon dioxide levels and effectively regulate ventilation. In patients with COPD who retain carbon dioxide, the chemoreceptors are not sensitive to small changes in carbon dioxide and regulate ventilation poorly. In these patients, it is the change in the oxygen level that stimulates changes in ventilation. Patients with COPD are at risk of retaining carbon dioxide and developing carbon dioxide narcosis induced by administration of high levels of oxygen. Uncontrolled oxygen administration may cause acute hypoventilation and carbon dioxide retention with dire consequences. Arterial oxygen saturation levels should be at 88% to 92% and no higher. Some patients with COPD have normal oxygen levels during the day but oxygen desaturation during sleep.

A patient with chronic obstructive pulmonary disease (COPD) has carbon dioxide retention and is ordered oxygen therapy. The nurse anticipates the use of which oxygen delivery system? a. Face tent b. Face mask c. Nasal cannula d. Nonrebreathing mask

C Oxygen can be delivered via the nasal cannula at flow rates of 1 to 2 L per minute, which deliver 24% to 28% FiO2 and are useful for patients with chronic lung disease. The face tent is used primarily for humidification and for oxygen only when the patient cannot or will not tolerate a tight-fitting mask. The FiO2 cannot be controlled, and there is no way to estimate how much oxygen is delivered. The simple face mask is used for short-term oxygen therapy. It fits loosely and delivers oxygen concentrations from 40% to 60%. The mask is contraindicated for patients with carbon dioxide retention because it will make the retention worse. When used as a nonrebreather, the plastic face mask with a reservoir bag delivers 60% to 100% oxygen at appropriate flow rates. This oxygen mask maintains a high-concentration oxygen supply in the reservoir bag. If the bag deflates, the patient breathes in large amounts of exhaled carbon dioxide.

The nurse is teaching a patient how to use a flow-oriented incentive spirometer (IS) the night before abdominal surgery. Which statement by the patient indicates an understanding of the procedure? a. "I need to get the balls to the top as quickly as possible." b. "Quick rapid breaths are the most effective when the incentive spirometer is used." c. "I need to keep the balls elevated as long as possible." d. "The balls must be elevated to be effective."

C The goal is to keep the balls elevated for as long as possible to ensure maximal sustained inhalation, not to snap the balls to the top of the chamber quickly with a rapid, brief, low-volume breath. Even if very slow inspiration does not elevate the balls, this pattern helps to improve lung expansion.