A patient with alcoholic cirrhosis, ascites, and gastrointestinal bleeding receives 4 units of red blood cells prior to anesthesia with isoflurane in oxygen for emergency exploratory laparotomy. After the peritoneum is opened and the fluid is drained, blood pressure decreases to 60/40 mmHg and SpO2 decreases to 90%. The most likely cause of the hypoxemia is
(A) acute myocardial ischemia
(B) decreased 2,3-diphosphoglycerate in transfused blood
During attempted awake intubation, the patient gags when the laryngoscope presses on the base of the tongue. Which of the following cranial nerves is responsible for the afferent limb of this reflex?
A 62-year-old woman with polycythemia vera is scheduled to undergo total knee arthroplasty using a tourniquet. Preoperative hematocrit is 60%. Which of the following is the most appropriate action?
(A) Perform total knee arthroplasty without use of a tourniquet
(B) Preoperative reduction of the hematocrit to 45% to 50%
(C) Prophylactic administration of aprotonin during surgery
(D) Prophylactic administration of epsilon-aminocaproic acid during surgery
(E) Prophylactic administration of low-dose heparin during surgery
B
The MAC of a volatile anesthetic agent is greatest when administered to which of the following groups of healthy patients?
A multigravid woman is receiving oxytocin by infusion for augmentation of labor. Fetal heart rate is 190 bpm with beat-to-beat variability of 6 to 8 bpm. The most appropriate immediate action would be to
(A) continue observation
(B) sample fetal scalp blood
(C) discontinue oxytocics
(D) administer a beta-adrenergic blocker to the mother