Ch. 19 Test, NIV Flashcards
Negative pressure ventilators cause air to enter the lungs by increasing ______________ pressure.
a. transairway
b. transpulmonary
c. transrespiratory
d. transthoracic
ANS: B
Transpulmonary pressure maintains alveolar inflation due to the decrease in pleural pressure caused by the negative pressure surrounding the chest wall. Positive pressure ventilators cause air to move into the lungs by increasing the pressure in the upper airways and in the conductive airways. Changes in transpulmonary pressure result in corresponding changes in alveolar volume. The transairway pressure is the gradient that produces airway movement in the conductive airways and represents the pressure caused by resistance to gas flow in the airways. The transrespiratory pressure is responsible for gas flow into and out of the alveoli during breathing. The transthoracic pressure is the pressure across the chest wall. It represents the pressure necessary to expand or contract the lungs and chest wall together.
DIF: 1 REF: p. 379
A patient with acute cardiogenic pulmonary edema (ACPE), as evidenced by pink, frothy secretions, arrives in the emergency department (ED) by ambulance with a nonrebreather mask (NRM) at 15 L/min. An arterial blood gas sample is drawn in the ED while the patient is on the NRM; the values are: pH = 7.50, PaCO2 = 28 mm Hg; PaO2 = 43 mm Hg; SaO2 = 84%; HCO3- = 24 mEq/L. After evaluating the situation, the respiratory therapist should suggest which of the following therapies?
a. IPPB with supplemental oxygen
b. Mask CPAP with supplemental oxygen
c. Postural drainage to clear the secretions
d. NPPV via nasal mask with postural drainage
ANS: B
The current recommendation for ACPE is for CPAP to be used initially. NPPV should be used only in patients who were hypercapnic and continue to be hypercapnic in spite of the CPAP. This patient is not hypercapnic at this time; therefore, mask CPAP is the appropriate therapy. IPPB is not appropriate because the positive effects of the therapy will be lost after a few minutes off the therapy.
DIF: 3 REF: p. 381
A patient has acute pulmonary edema from left-sided heart failure and acute hypoxemic respiratory failure that has not responded to conventional pharmacologic and oxygen therapy. As the next line of therapy, the respiratory therapist should recommend which of the following?
a. Noninvasive positive pressure ventilation
b. Continuous positive airway pressure
c. Intubation and mechanical ventilation
d. Bronchial hygiene therapy
ANS: B
The current recommendation for ACPE is for CPAP to be used initially. NPPV should be used only in patients who were hypercapnic and continue to be hypercapnic in spite of the CPAP.
DIF: 1 REF: p. 381
One of the physiological goals of NPPV in acute respiratory failure is to improve gas exchange by ______________.
a. resting the respiratory muscles
b. decreasing the effect of secretions
c. increasing right ventricular preload
d. decreasing the functional residual capacity
ANS: A
The physiological goal in acute respiratory failure is to improve gas exchange by resting the respiratory muscles and increasing alveolar ventilation.
DIF: 1 REF: p. 380
The primary goal of NPPV in the acute care setting is to do which of the following?
a. Improve sleep quality
b. Decrease muscle fatigue
c. Avoid invasive ventilation
d. Eliminate nocturnal hypopnea
ANS: C
Avoidance of intubation and invasive ventilation is the primary goal of NPPV in the acute care setting. The other options are benefits of NPPV, but they are not the primary goal in the acute care setting.
DIF: 1 REF: p. 380
Patients with chronic hypoventilation disorders need a minimum of _________hours of NPPV to experience improved quality of life.
a. 2 to 4
b. 4 to 6
c. 6 to 8
d. 8 to 10
ANS: B
Nocturnal use of NPPV (4 to 6 hours) can have certain clinical benefits for patients with chronic hypoventilation disorders. The most significant of these are improvement of symptoms associated with chronic hypoventilation and an improved quality of life.
DIF: 1 REF: p.384
NPPV is considered the standard of care for the treatment of which of the following?
a. COPD exacerbation
b. Asthma exacerbation
c. Cardiogenic pulmonary edema
d. Community acquired pneumonia
ANS: A
NPPV currently is considered the standard of care for the treatment of COPD exacerbation in selected patients. Specific criteria for the selection of asthma patients to receive NPPV have not yet been developed. NPPV may be appropriate in patients who do not respond to conventional treatment methods. Unless a patient has COPD and CAP, caution should be used when treating patients with NPPV. Mask CPAP is the standard of care for ACPE.
DIF: 1 REF: p. 380, 381
A 75-year-old man with a long history of COPD is brought to the emergency department with shortness of breath. He has a persistent, productive cough with green purulent sputum, cyanosis of the lips and extremities, and is uncooperative. His arterial blood gas values on 2 L/min by nasal cannula are: pH = 7.25; PaCO2 = 90 mm Hg; PaO2 = 38 mm Hg; SaO2 = 59%; HCO3- = 38 mEq/L. The most appropriate action at this time is which of the following?
a. IPPB
b. Mask CPAP
c. NPPV via full face mask
d. Invasive mechanical ventilation
ANS: D
This patient meets the blood gas criteria for moderate to severe respiratory failure and therefore needs ventilatory support, as evidenced by the pH 45 mm Hg; the PaO2/FIO2 is estimated at 38/0.28 = 136. This patient is at risk for failure of NPPV because he is uncooperative (probably due to hypoxia) and has excessive secretions, as evidenced by his persistent productive cough.
DIF: 3 REF: p. 383
A 61-year-old female was admitted last night with shortness of breath. She currently is alert and oriented, but very anxious. Her latest arterial blood gas values, on a nasal cannula at 3L/min, show: pH = 7.39; PaCO2 = 41 mm Hg; PaO2 = 40 mm Hg; SaO2 = 74%; HCO3- = 24 mEq/L. Breath sounds are decreased throughout with fine late crackles on inspiration. The current chest x-ray shows an enlarged heart with bilateral vascular congestion. The most appropriate therapy for this patient is _________.
a. NIPPV
b. mask CPAP
c. invasive ventilation
d. nonrebreather mask
ANS: B
The arterial blood gas values for this patient show refractory hypoxemia, as evidenced by the PaO2 of 40 mm Hg while receiving supplemental oxygen. The breath sounds indicate pulmonary edema. This finding is supported by the chest x-ray, which shows bilateral vascular congestion and an enlarged heart. These findings are consistent with acute cardiogenic pulmonary edema. The most appropriate therapy is mask CPAP.
DIF: 3 REF: p. 381
A patient with acute cardiogenic pulmonary edema is to be placed on CPAP. What should the initial setting be?
a. 3 to 5 cm H2O
b. 5 to 7 cm H2O
c. 10 to 12 cm H2O
d. 15 to 20 cm H2O
ANS: C
The current recommendation is that CPAP at 10 to 12 cm H2O be used initially in the treatment of ACPE.
DIF: 1 REF: p. 381
A 62-year-old male patient with COPD is being seen in the pulmonary clinic for dyspnea at rest and daytime hypersomnolence. The patient has been hospitalized three times in the past year for COPD exacerbations and once for pneumonia. He currently uses 2 L/min oxygen from a concentrator all the time. The patient reports that he is able to sleep only about 2 hours each night and that he has a headache every morning. Which of the following should be recommended to the physician?
a. Chest cuirass
b. Nocturnal NPPV
c. Nocturnal CPAP
d. Tracheostomy and ventilation
ANS: B
This patient shows signs of nocturnal hypoventilation and poor sleep quality, as evidenced by the daytime hypersomnolence, dyspnea, and morning headache. This patient should be assessed further for the use of nocturnal NPPV by testing for oxygen saturation overnight.
DIF: 3 REF: p. 384
A patient who was diagnosed 1 year ago with amyotrophic lateral sclerosis is being seen in his primary care physician’s office. The patient is complaining of fatigue and inability to concentrate at work. The patient’s FVC is 45% of predicted, the PaCO2 is 47 mm Hg, and the MIP is 54 cm H2O. Which of the following should be considered for this patient?
a. Continuation of current therapy
b. Supplemental home oxygen
c. Nocturnal CPAP
d. Nocturnal NPPV
ANS: D
Amyotrophic lateral sclerosis is a progressive neurodegenerative disease that eventually leads to total paralysis. This patient has degenerated to the point where he meets the physiological criteria for the use of NPPV, as evidenced by the FVC below 50% of predicted, the MIP below 60 cm H2O, and the PaCO2 above 45 mm Hg. This patient needs to be monitored closely for loss of oropharyngeal muscle strength and ability to generate an effective cough.
DIF: 3 REF: p. 385, Table 19-2
To use CPAP successfully, a patient must have which of the following?
a. Adequate PaO2
b. Secure artificial airway
c. PaCO2 > 40 mm Hg
d. Adequate spontaneous ventilation
ANS: D
To use CPAP successfully, a patient must be able to breathe spontaneously.
DIF: 1 REF: p. 384-386
The variable that ends pressure support breaths from a PTV system is ______________.
a. time
b. flow
c. pressure
d. volume
ANS: B
Each pressure-supported breath is flow triggered and flow cycled.
DIF: 1 REF: p.386
A patient in the subacute care unit is receiving NPPV with a PTV system, with an IPAP of 10 cm H2O and an EPAP of 2 cm H2O. The patient’s latest arterial blood gas values reveal an increase in the PaCO2. The most appropriate action to take is which of the following?
a. Increase the IPAP.
b. Decrease the IPAP.
c. Increase the EPAP and IPAP.
d. Intubate and mechanically ventilate.
ANS: C
The EPAP of 2 cm H2O is not providing enough continuous flow of gas through the system to minimize the rebreathing of CO2. Increasing both the EPAP and IPAP will provide enough flow to wash out the CO2 and keep the pressure support DIF consistent.
DIF: 3 REF: p. 386
