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
After two hours of anesthesia with halothane 1.2% and oxygen, nitrous oxide 75% is added to the inspired gas mixture. This addition would
(A) increase the alveolar halothane and oxygen concentrations above inspired
(B) increase the alveolar halothane concentration only
(C) cause no change in alveolar gas concentrations compared with inspired
(D) decrease alveolar oxygen concentration compared with inspired
(E) decrease alveolar oxygen and halothane concentrations below inspired
A
The two E oxygen cylinders on an anesthesia machine have pressure readings of 1100 psi each. At an oxygen flow of 3 L/min, there will be sufficient oxygen for approximately
In a healthy 70-kg adult, which of the following is the most likely effect of intravenous administration of morphine 10 mg on ventilatory responses?
(A) Increased response to hypoxia and decreased response to hypercarbia
(B) Decreased response to hypercarbia and no change in response to hypoxia
(C) Decreased response to both hypoxia and hypercarbia
(D) No change in response to hypercarbia and decreased response to hypoxia
(E) No change in response to hypoxia or hypercarbia
C
A 58-year-old man with a history of angina is undergoing resection of an abdominal aortic aneurysm under morphine, nitrous oxide, d-tubocurarine anesthesia. Just before removal of the aortic cross-clamp, heart rate is 74 bpm, blood pressure is 115/70 mmHg, and pulmonary artery occlusion pressure is 7 mmHg. Immediately after removal of the cross-clamp, heart rate increases to 120 bpm, blood pressure decreases to 80/55 mmHg, and pulmonary artery occlusion pressure decreases to 3 mmHg. The V5 lead on the EKG demonstrates sudden ST-segment depression and T-wave inversion. Initial therapy should be
(A) reapplication of the aortic cross-clamp
(B) intravenous administration of sodium bicarbonate
(C) initiation of a phenylephrine infusion
(D) rapid expansion of blood volume by transfusion
A 2500-g, 12-hour-old infant is tracheally intubated and mechanically ventilated at a rate of 20/min with an FiO2 of 0.4 and peak inspiratory pressure of 25 cmH2O. At birth, amniotic fluid was meconium stained and Apgar scores were 2 and 7. The most recent arterial blood gas levels are PaO2, 50 mmHg, PaCO2, 55 mmHg, and pH 7.20. The most appropriate management is to
(A) administer sodium bicarbonate
(B) begin intravenous infusion of prostaglandin E,