During cardiopulmonary bypass at a nasopharyngeal temperature of 28°C and a hematocrit of 20%, temperature-corrected PaCO2 is 50 mmHg and uncorrected PaCO2 is 60 mmHg. The most appropriate management is to
(A) administer additional opioid
(B) administer packed red blood cells to increase hematocrit to 25%
A 60-kg, 70-year-old man requires open reduction and internal fixation of an intertrochanteric fracture sustained 24 hours ago. Serum creatinine concentration is 1 mg/dl and blood urea nitrogen concentration is 40 mg/dl. The most likely cause of these findings is
A healthy 18-year-old youth is scheduled for an emergency operation for removal of a steel splinter from his right iris. Anesthesia is induced with thiopental and pancuronium and, following tracheal intubation, is maintained with nitrous oxide 2 liters, oxygen 2 liters, and halothane 1.5%. Conjunctival instillation of phenylephrine solution 10% increases blood pressure from 110/70 to 230/110 mmHg and decreases pulse from 70 to 46 bpm. The ECG shows a bigeminal pattern. The most appropriate treatment is to
(A) administer lidocaine
(B) administer atropine
(C) administer propranolol
(D) decrease halothane
(E) administer nitroprusside
E
Which of the following is the most likely cause of apnea occurring after a retrobulbar block?