A 63-year-old, 5'11", 185 lb male patient with a history of chronic obstructive pulmonary disease (COPD) is admitted to the hospital due to liver failure. Over the course of the 48 hours he has developed respiratory distress

Question

The respiratory therapist performs a physical assessment and finds the following: heart rate 135 beats/min, respiratory rate 28 with accessory muscle use. Breath sounds are decreased bilaterally with coarse crackles in the right base. A chest X-ray from 24 hours ago shows bilateral lower lobe infiltrates. The patient has a nonproductive cough. The respiratory therapist draws an arterial blood gas that reveals: pH 7.31; partial pressure of carbon dioxide (PaCO2) 57 mm Hg; partial pressure of oxygen (PaO2) 58 mm Hg; arterial oxygen saturation (SaO2) 87%; bicarbonate (HCO3–) 27 mEq/L while receiving oxygen via nasal cannula 3 L/min. The respiratory therapist should recommend which of the following for this patient?
a. Continue with current therapy and moni-tor the patient closely.
b. Place the patient on a nonrebreather mask with 15 L/min oxygen.
c. Intubate and place on pressure-controlled continuous mandatory ventilation (PC-CMV), peak inspiratory pressure (PIP) 40 cm H2O, positive end-expiratory pressure (PEEP) 8 cm water (H2O), frac-tional inspired oxygen (FIO2) 1.0.
d. Use BiPAP with IPAP 10 cm H2O, EPAP 5 cm H2O, and bleed in 4 L/min oxygen.

Answer 1

ANS: D
This patient is showing signs of ventilatory failure as evidenced by his acute-on-chronic respira-tory acidosis with uncorrected hypoxemia. This patient should be tried on noninvasive positive pressure ventilation (NPPV) prior to intubation to try to avoid it if possible. Using a nonrebreath-er mask would not address the patient's ventilatory problem and may cause oxygen-induced hypoventilation. Continuing with current therapy would not address the problem of impending ventilatory failure. If intubated and mechanically ventilated with pressure-controlled continuous mandatory ventilation (PC-CMV), starting off at 40 cm H2O is too high. When the peak inspira-tory pressure (PIP) or plateau pressure (Pplateau) from volume ventilation are not available, an initial pressure of 10-15 cm H2O should be set followed by volume measurements and pressure adjust-ments when appropriate.