Syringe A contains 100 ml of normal blood with a PO2 of 2 mmHg, and syringe B contains 100 ml of normal blood with a PO2 of 98 mmHg. The contents of the two syringes are mixed anaerobicaily to equilibrium. The PO2 of the resultant mixture Is
A woman with chronic obstructive pulmonary disease is extubated and minimally responsive after isoflurane anesthesia. She is receiving oxygen 6 L/min through a face mask. Respirations are 10/min, PaO2 is 68 mmHg, PaCO2 is 54 mmHg, and pH is 7.28. The most likely cause of the respiratory acidemia is
(A) blunted sensitivity to low pH in the medullary respiratory center
(B) chronic carbon dioxide retention
(C) decreased lung volume from supine positioning
(D) depression of carotid body chemoreceptors by halothane
(E) suppression of hypoxic ventilatory drive by supplemental oxygen
A 60-year-old woman who is taking propranolol for hypertension and is allergic to penicillin is anesthetized with thiopental and halothane for resection of an abdominal aortic aneurysm. Shortly after intubation she is given vancomycin 500 mg intravenously, after which her blood pressure decreases from 140/80 to 70/50 mmHg while her heart rate remains steady at 64 bpm. The most likely explanation for the decrease in blood pressure is
(A) cross-sensitivity of penicillin and vancomycin
(B) interaction of vancomycin and propranolol
(C) vancomycin-induced anaphylactoid reaction
(D) interaction of halothane and propranolol
(E) interaction of halothane and vancomycin
C
Which of the following statements concerning the management of diabetes mellitus during pregnancy is true?
(A) Insulin requirements remain essentially unchanged during pregnancy
(B) Maternal blood glucose concentration of 200 mg/dL is optimal
(C) Maternal hyperglycemia may cause neonatal acidosis
(D) Neonatal hyperglycemia is common
(E) Infants delivered under general anesthesia have lower Apgar scores than those delivered under spinal anesthesia
Ten days after sustaining burns over 40% of his body surface area, a patient requires greater than expected doses of vecuronium for adequate relaxation of skeletal muscle. The primary cause is increased
A 50-year-old man with severe coronary artery disease undergoes coronary artery bypass grafting. Five minutes after successful termination of cardiopulmonary bypass, ST-segment elevation is noted in lead II of the ECG, and the following findings are noted: BP 70/40, Pulse 80, CVP 16 cmH2O, PAp 25/10. Appropriate management is to
Following a vaginal hysterectomy in the lithotomy position under general anesthesia, a patient has numbness of the lateral aspect of the left calf and medial half of the dorsum of the left foot. On physical examination she has footdrop and the toes cannot be extended. Which nerve is most likely to be involved?