A 70-kg, 46-year-old man is undergoing clipping of a cerebral aneurysm with nitrous oxide, opioid, relaxant anesthesia. He is otherwise healthy. As the surgeons are about to enter the dura, the brain is noted to be tense and bulging. Heart rate is 100 bpm and mean arterial pressure is 90 mmHg. PaO2 is 120 mmHg, PaCO2 is 23 mmHg, and pH is 7.50. Which of the following should be done immediately?
(A) Hyperventilation to a PaCO2 of 15 to 20 mmHg
(B) Administration of furosemide 20 mg intravenously
(C) Administration of mannitol 0.5 g/kg
(D) Administration of thiopental 250 mg in increments
A 5-year-old child undergoes strabismus correction during spontaneous ventilation with halothane 1.5%, nitrous oxide and oxygen 50%. Intravenous atropine 0.2 mg is administered after inhalation induction. Ten minutes after incision, heart rate decreases from 110 bpm to 40 bpm. Which of the following is the most likely cause?
(A) Administration of phenylephrine eyedrops
(B) Inadvertent external pressure on the carotid sinus
(C) Paradoxical response to a small dose of atropine
Addition of 20 cmH2O positive end-expiratory pressure to a patient receiving controlled mechanical ventilation decreases cardiac output and left ventricular function by
A 20-kg, 6-year-old boy is undergoing strabismus surgery under anesthesia with sevoflurane, nitrous oxide, and oxygen. The heart rate suddenly decreases from 85 to 40 bpm. Which of the following is the most appropriate first step in management?
A 16-year-old patient who sustained trauma is being resuscitated. In deciding whether to infuse lactated Ringer's solution or albumin, which of the following is true?
(A) At one hour, both will remain in the intravascular compartment to an equal extent
(B) Both have zero risk for hepatitis transmission
(C) Both will decrease ionized calcium levels
(D) The glomerular filtration rate will be higher with infusion of albumin
(E) Lactated Ringer's solution causes a greater increase in intracranial pressure
B
Which of the following statements concerning monitoring of neuromuscular function during general anesthesia is true?
(A) Facial nerve electrodes underestimate recovery from block, compared with ulnar nerve electrodes
(B) More current is required to depolarize a nerve beneath the negative electrode than beneath the positive electrode
(C) Needle electrodes should be electrically grounded
(D) Supramaximal voltage is 10% higher than the voltage required to elicit pain in the awake patient
(E) The amount of neuromuscular block is underestimated if electrodes are placed on a paretic limb
Three hours prior to induction of anesthesia for elective laparotomy, a 40-kg 8-year-old boy is anxious and clings to his parents. Which of the following preanesthetic medications is most appropriate?