A 7-year-old, obese, 30-kg boy was anesthetized using an adult circle system containing a 3-liter bag and mask. Induction with nitrous oxide (2 liters), oxygen (1 liter), and enflurane 3% was characterized by three minutes of hyperventilation followed by apnea. Forty-five seconds later, the child moved and became difficult to control. The most likely cause of the movement is
(A) decreased alveolar concentration of enflurane during the period of apnea
(B) excessive uptake of enflurane by the child's fat
(C) higher fresh gas flows required with use of an adult circle system in a child
A 62-year-old woman with obesity and type II diabetes mellitus is scheduled to undergo vitrectomy of the right eye. Five minutes after retrobulbar injection with 0.75% bupivacaine 4 ml and intravenous administration of fentanyl 50 ju-g and midazolam 1 mg, she is apneic and unresponsive. Which of the following is the most likely cause?
(A) Fentanyl-midazolam interaction
(B) Hypoglycemia
(C) Intravenous bupivacaine
(D) Retrobulbar hematoma
(E) Subarachnoid bupivacaine
C
Each of the following is a complication of stellate ganglion block EXCEPT
A direct 5-joule shock is unsuccessful in converting ventricular fibrillation occurring after discontinuation of cardiopulmonary bypass. The most appropriate next step is to
(A) administer calcium chloride
(B) administer bretylium
(C) administer regular insulin
(D) administer sodium bicarbonate
(E) increase shock energy
E
Which of the following best describes the relationship between cerebral perfusion pressure and cerebral blood flow in a patient with untreated chronic hypertension?
(A) It is constant at mean blood pressures between 50 and 150 mmHg
(B) It is linear for all blood pressures
(C) Flow versus pressure curve is hyperbolic
(D) Flow versus pressure curve is shifted to the right
(E) Flow versus pressure curve is shifted to the left
During a cardiac arrest with effective chest compression and positive-pressure ventilation, 50 mEq of sodium bicarbonate is administered. Which of the following is the most likely result?
Which of the following findings on the left is most likely to be associated with an increased risk of complications with cannulation of the left internal jugular vein compared with cannulation of the right internal jugular vein?
(A) Longer recurrent laryngeal nerve
(B) Lower location of the cupola of the pleura
(C) More acute angle between the internal jugular and innominate veins