A 36-year-old female patient with a history of asthma is admitted to the ICU from the emergen-cy department. Her respirations are 30, very labored, with accessory muscle use and bilateral in-spiratory and expiratory wheezing

There is bilateral hyperresonance during chest percussion. A blood gas taken in the ICU after 1 hour of continuous aerosolized albuterol (15 mg) reveals: pH 7.38, partial pressure of carbon di-oxide (PaCO2) 42 mm Hg, partial pressure of oxygen (PaO2) 53 mm Hg, oxygen saturation (SaO2) 88%, bicarbonate (HCO3?) 25 mEq/L with nasal cannula 6 L/min. The patient is 5'5" and weighs 135 lb. The most appropriate action at this time is which of the following?
a. Continue current therapy with 20 mg al-buterol and reassess in 1 hour.
b. Noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pres-sure (bilevel PAP), f = 12, inspiratory pos-itive airway pressure (IPAP) 28 cm H2O, expiratory positive airway pressure (EPAP) 3 cm H2O, fractional inspired ox-ygen (FIO2) 0.30
c. Intubate, use pressure-controlled continu-ous mandatory ventilation (PC-CMV), f = 8, peak inspiratory pressure (PIP) 28 cm H2O, TI 0.75 seconds, positive end-expiratory pressure (PEEP) 3 cm H2O, FIO2 1.0
d. Intubate, use volume-controlled continu-ous mandatory ventilation (VC-CMV), f = 12, tidal volume (VT) 600 mL, PF 40 L/min, PEEP 5 cm H2O, FIO2 0.60

ANS: C
The assessment and arterial blood gases (ABG) for this patient reveal impending respiratory fail-ure. This patient should be intubated and may possibly require sedation and paralysis, depending on the ability to ventilate with synchrony. Therefore, continuation of the current therapy is not appropriate. Noninvasive positive pressure ventilation (NPPV) is not appropriate with asthma pa-tients who are in respiratory failure and may be unable to provide airway protection. The settings for the volume-controlled continuous mandatory ventilation (VC-CMV) are not appropriate be-cause the tidal volume is set too high, the frequency too low, and the peak flow too low. This would not allow enough time for exhalation and may cause barotrauma. The pressure-controlled continuous mandatory ventilation (PC-CMV) mode will allow for more control over the pres-sures. The short expiratory time will allow time for exhalation that will decrease the likelihood of hyperexpansion of the lungs.