A 65-year-old man undergoes prostatectomy in the lithotomy position under spinal anesthesia using bupivacaine 12 mg. Ten hours later, he reports that his left foot is numb. Examination shows decreased pinprick sensation over the lateral dorsal aspect of the left foot; dorsiflexion is limited. Which of the following is the most likely cause?
A 35-year-old woman with severe myasthenia gravis is scheduled for thymectomy. Which of the following preoperative pulmonary function tests is most likely to be normal?
A 40-year-old man is undergoing open reduction and internal fixation of a fractured femur. During anesthesia with fentanyl, sevoflurane, and oxygen, heart rate decreases to 20 bpm and 6 premature ventricular contractions per minute are noted. No pulse is detected. The most appropriate next step is to
A patient has sudden cardiopulmonary arrest five minutes after retrobulbar block with 0.75% bupivacaine 2 ml with hyaluronidase for ophthalmologic surgery. No premonitory changes were noted on the pulse oximeter. The most likely cause is
(A) allergic reaction to hyaluronidase
(B) direct cardiac toxicity
(C) oculocardiac reflex
(D) intravenous injection of local anesthetic
(E) subarachnoid injection of local anesthetic
E
Peak airway pressure increases from 25 to 50 cmH2O when beginning right endobronchial ventilation with a right double-lumen tube. The most likely explanation for this increase is
(A) failure to decrease tidal volume
(B) inadvertent intubation of the left mainstem bronchus
(C) intrinsic resistance of small endobronchial lumina
(D) obstruction of the orifice of the right upper lobe