Following a right lower lobectomy, a patient develops a bronchopleural fistula and becomes hypoxic. He is orally intubated and mechanically ventilated with pure oxygen. PaO2 is 65 mmHg, PaCO2 is 70 mmHg, and pH is 7.25. Which of the following will produce the most favorable change in the blood gases?
An elderly man has an acute dissection of the descending thoracic aorta. Which of the following antihypertensive therapies is most likely to extend the dissection?
Compared with thiopental, methohexital is characterized by
A 54-year-old woman who is scheduled to undergo emergency exploratory laparotomy takes warfarin sodium for anticoagulation. Prothrombin time is 19 sec (control 12 sec). Which of the following agents is most appropriate to reverse the effects of warfarin?
An 8-year-old child with chronic renal failure is scheduled for an operation to create an arteriovenous fistula. Laboratory studies include: Hemoglobin 6.5 g/dl, Blood gases (breathing air) : PaO2 97 mmHg, PaCO2 29 mmHg, pH 7.30 Sodium 129 mEq/L Potassium 5.5 mEq/L Chloride 101 mEq/L Bicarbonate 15 mEq/L. Before inducing general anesthesia, which of the following abnormalities should be corrected?
If both recurrent laryngeal nerves were severed during a difficult thyroidectomy for cancer, the most likely finding would be
A 68-year-old man has a permanent DVI pacemaker that has been functioning appropriately. Which of the following is most likely to cause conversion to VOO pacing?
Four days after mitral valve replacement, a 49-year-old, 70-kg woman who has had oliguric renal failure since the operation requires insertion of a Schribner shunt for hemodialysis. Her BUN concentration is 104 mg/dl, serum creatinine is 9.3 mg/dl, serum sodium is 130 mEq/L, and serum potassium is 6.7 mEq/L. During the operation under local anesthesia, diazepam 7.5 mg and morphine 10 mg are administered intravenously to control agitation. Five minutes later while she is sleeping quietly, unifocal premature ventricular contractions appear at a rate of 10 per minute on the ECG monitor. The most appropriate therapy is to
A 20-kg, 5-year-old boy under treatment for five days for a cerebral contusion not requiring an operation is still unconscious. After three days of mechanical ventilation, humidified oxygen 40% via T-tube is started. Arterial blood gas analysis shows PaO2 120 mmHg, PaCO2 44 mmHg, pH 7.48, and base excess +6. A nasogastric tube is in place and draining to gravity. Daily fluid therapy has been 5% dextrose in 0.5 normal saline solution 500 ml and 5% dextrose in lactated Ringer's solution 500 ml. Serum electrolyte concentrations are sodium 140, potassium 3.2, and chloride 91 mEq/L. Serum osmolality is 300 mOsm/L. Urine output averages 15 ml/hour. Dexamethasone 8 mg/day has been the only drug therapy. This patient most likely requires
Intraocular pressure is