Pulmonary Disorders I

propofol would not be ideal (Answer A is incorrect).

Succinylcholine causes the up-regulation of acetylcholine

receptors, predisposing the muscle fibers to release

excess potassium because they are depolarized, which

leads to significant dysrhythmias or cardiac arrest

(Answers B and D are incorrect). Appropriate induction

and neuromuscular blockade in this patient would be to

administer etomidate (indicated for hemodynamically

unstable

patients),

fentanyl

(providing

adequate

analgesia), and rocuronium (does not increase serum

potassium) (Answer C is correct).

Answer: B

Although propofol may promptly lower ICP, it can also

induce hypotension and thus decrease cerebral perfusion

pressure (Answer A is incorrect). Midazolam could be

used as an induction agent; however, it is not the best

agent for RSI because of its delayed onset of action

(Answer C is incorrect). Etomidate may be considered

in the setting of increased ICP; however, the dose in this

case is too high (Answer D is incorrect). Ketamine not

only decreases ICP but also prevents fluctuations in ICP

(Answer B is correct).

Answer: A

After recognizing that the patient has ARDS, a lung-

protective ventilation strategy should be implemented

(tidal volume 4–6 mL/kg). Choosing a PS or SIMV

mode would allow the patient to initiate spontaneous

breaths in excess of the goal tidal volume (Answers B–D

are incorrect). In the ARDSNet study of tidal volume

strategy, the AC mode was most commonly used to

promote the application of low tidal volumes (Answer

A is correct).