Eight hours after abdominal surgery, a 51-year-old patient becomes increasingly somnolent. Epidural morphine 5 mg was administered immediately following the procedure. Postoperatively, respiratory rate has not decreased below 12/min and Sp02 has remained greater than 92%. Arterial blood gas analysis shows Pa02 80 mmHg, PaC02 82 mmHg, and pH 7.1. Which of the following is the most appropriate conclusion?
(A) Analysis of the blood sample was delayed
(B) The blood sample was venous rather than arterial
(C) The patient is receiving supplemental oxygen
(D) The pulse oximeter readings are falsely high
(E) No treatment is required at this time
C
The condition LEAST likely to be associated with sustained pain relief following a nerve block is
During a reoperative total hip arthroplasty requiring transfusion of 8 units of packed red blood cells, blood begins to ooze from the operative field and intravenous catheter sites. Urine is pink. The most likely cause is
In a patient with adult respiratory distress syndrome who is being mechanically ventilated, which of the following findings indicates the most severe disease?
A 55-year-old woman who is scheduled to undergo carotid endarterectomy has a history of essential hypertension and chronic obstructive pulmonary disease. Over a 30-minute period beginning one hour after induction of general anesthesia, Sp02 decreases from 99% to 95%. During that time, she has received fentanyl 100 mcg, isoflurane 1%, nitrous oxide 49.5%, oxygen 49.5%, and a nitroglycerin infusion to maintain blood pressure at approximately 160/95 mmHg. Which of the following is the most likely cause for the decline in oxygen saturation?
(A) Decreased cardiac output
(B) Increased dead space ventilation
(C) Inhibition of hypoxic pulmonary vasoconstriction
A 13-year-old African American boy has severe abdominal pain after debridement of an open fracture of the lower extremity. His hemoglobin concentration is 10 g/dl and a peripheral blood smear shows elongated crescent-shaped erythrocytes. The most appropriate initial therapy is
(A) sodium bicarbonate administration
(B) dopamine infusion
(C) blood transfusion
(D) volume loading with crystalloid
(E) high-dose corticosteroid administration
D
With long-term administration, which of the following drugs produces the most prolonged sedative effect of diazepam?
(A) Cimetidine
(B) Famotidine
(C) Metoclopramide
(D) Ranitidine
(E) Warfarin
A
Which of the following statements concerning cerebral vasospasm following intracranial hemorrhage is true?
(A) It is accompanied by paradoxical intracranial hypotension
(B) It responds to nitroprusside therapy
(C) It persists more than 48 hours after hemorrhage
(D) It is exacerbated by intravascular volume expansion
(E) It is confirmed by ST-T wave changes in the absence of myocardial ischemia