Nitrous oxide is contraindicated during
Postdural puncture headache occurs most commonly in which of the following patients?
A 26-year-old patient with multiple trauma is admitted to the intensive care unit postoperatively. The early development of polyuria, hypotension, low urine sodium excretion, high serum osmolality, and normal serum creatinine concentration is best explained by
A 33-year-old primigravid woman with myasthenia gravis, well-controlled with pyridostigmine, is in labor with the cervix dilated 7 cm. She has a headache and feels very nervous. Blood pressure is 160/115 mmHg, she has 3+ pitting edema, and urinalysis shows 4+ protein. Appropriate management of her labor should include
Each of the following findings is characteristic of chronic reflex sympathetic dystrophy of the extremities EXCEPT
After weaning from cardiopulmonary bypass following mitral valve replacement, a patient's cardiac output is reported to be 3.7 L/min measured by thermodilution technique using 5% dextrose in water 10 ml at room temperature as injec-tate. This value could be falsely high if
If a patient with excessive bleeding during exploratory laparotomy has a normal activated clotting time, the LEAST likely cause of the bleeding is
A 20-year-old woman with poorly controlled diabetes mellitus is scheduled for urgent drainage of an abdominal abscess. She received an initial dose of regular insulin 10 units followed by regular insulin 5 units/hr for the past five hours. Laboratory studies show serum sodium concentration 128 mEq/L, potassium 5.4 mEq/L, chloride 80 mEq/L, and glucose 750 mg/dl. The most appropriate perioperative management is
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 62-year-old man with severe emphysema was treated for the sixth time with assisted mechanical ventilation (Fi02 0.6, peak inspiratory pressure 25 mmHg, rate 22/min, insp/exp 0.3). Arterial blood gas values with this therapy are Pa02 73 mmHg, PaC02 48 mmHg, and pH 7.32. During the second day of treatment he suddenly becomes dusky, with increased respiratory rate. Arterial blood gas values are Pa02 42 mmHg, PaC02 67 mmHg, and pH 7.25. Tracheal lavage and suction fail to improve his condition. The therapeutic measure most likely to correct this acute episode is to