During cardiopulmonary bypass, the perfusionist notes that the mixed venous oxygen saturation has decreased from to 55%. Which of the following is the most likely cause?
Which of the following statements concerning anesthesia machine flowmeters is true?
A 70-kg, 77-year-old man Is undergoing left nephrectomy with nitrous oxide, oxygen, fentanyl, and midazolam anesthesia. He has a 90 pack-year history of cigarette smoking and has chronic obstructive pulmonary disease. One hour after incision, expiratory wheezing occurs and peak Inspiratory pressure increases from 35 to 65 cmH20; end-tidal PCO2 is unchanged, but SpO2 decreases from 97% to 88%. The most likely cause is
One hundred children who are to have strabismus surgery are enrolled in a research protocol. Fifty receive a new antiemetic and 50 receive a placebo preoperatively. Fifteen children in the treatment group and 37 children in the control group have nausea and vomiting postoperatively. Which of the following analyses is most appropriate for determining the statistical significance of the group differences?
The syndrome of inappropriate ADH secretion is characterized by
Which of the following statements concerning use of amitriptyline to treat chronic pain is true?
One day after a vaginal hysterectomy under epidural anesthesia, a patient has numbness and inability to dorsiflex the right foot. Her legs were placed in leg holders during the operation. The most likely cause is
A 65-year-old man with essential hypertension well controlled around 140/90 mmHg with hydrochlorothiazide is scheduled for right colectomy for carcinoma. Preoperative EKG and all laboratory values are normal except for a hematocrit of 29% and serum potassium level of 3.2 mEq/L. Central venous pressure (CVP) measured from an internal jugular catheter inserted before induction of anesthesia is 7 mmHg. Ten minutes after induction with thiopental 200 mg followed by enflurane 3% in nitrous oxide and oxygen (50% each), blood pressure decreases suddenly from 110/70 to 80/50 mmHg with heart rate unchanged at 78 bpm. CVP is now 20 mmHg and the EKG demonstrates a midjunctional rhythm. After discontinuing the enflurane, the most appropriate action would be to
A 60-kg, 70-year-old man requires open reduction and internal fixation of an intertrochanteric fracture sustained 24 hours ago. Serum creatinine concentration is 1 mg/dl and blood urea nitrogen concentration is 40 mg/dl. The most likely cause of these findings is
A conscious patient has an acute subdural hematoma that will require surgical evacuation. Which of the following interventions to be carried out in the emergency department is most likely to decrease intracranial pressure?