An axillary block is administered to a 60-kg patient using 40 ml of 0.5% bupivacaine. Ten minutes after placement of the block, the patient has a seizure. Which of the following statements is true?
(A) A low serum albumin concentration could have contributed to the occurrence of the seizure
(B) CNS hypoperfusion is the most likely cause of the seizure
(C) The seizure was probably secondary to an allergic reaction to the local anesthetic
(D) The use of an equipotent dose of lidocaine rather than bupivacaine would have decreased the likelihood of
A 60-kg, 45-year-old woman who takes digoxin for atrial fibrillation receives furosemide 40 mg and mannitol 60 g during resection of a supratentorial meningioma. After initiation of hyperventilation to decrease PaC02 from 35 to 20 mmHg, multifocal premature ventricular contractions are noted on the ECG. The most likely cause is
In a healthy patient receiving an epidural analgesic infusion postoperatively, clear fluid is noted to drip back freely from the epidural catheter. Which of the following findings correctly identifies the associated fluid?
(A) Precipitation when mixed with an equal volume of pancuronium = local anesthetic
Following maternal epidural injection, fetal exposure to chloroprocaine is lower than fetal exposure to bupivacaine for which of the following reasons?
(A) Chloroprocaine is metabolized by plasma cholinesterase
(B) Chloroprocaine is more protein bound
(C) Chloroprocaine is not readily absorbed from the epidural space
(D) The ionized fraction of chloroprocaine in the fetal circulation is smaller
(E) The pKa of chloroprocaine is less than that of bupivacaine
A woman is in labor at 40 weeks' gestation and the fetus is in breech presentation. Which of the following will provide adequate uterine relaxation for vaginal delivery?
Which of the following statements concerning use of temperature-corrected blood gas measurement (pH-stat) during hypothermic cardiopulmonary bypass is true?
(A) Blood gas analysis is performed at the patient's temperature
(B) Carbon dioxide should not be added to the bypass circuit
(C) The carbon dioxide content of the patient's blood is greater than it would be without temperature correction
(D) The incidence of postoperative neurologic deficits is increased compared with the alpha-stat method
(E) The patient's temperature should be maintained above 25°C