You see a flash of fire from the endotracheal tube of a patient undergoing carbon dioxide laser excision of laryngeal polyps. The immediate response should be to
(A) discontinue the fresh gas flow
(B) increase the nitrous oxide concentration
(C) spray water down the endoscope
(D) insert wet pads into the pharynx
(E) remove the endotracheal tube
E
A 40-year-old man is undergoing open reduction and internal fixation of a fractured femur. During anesthesia with fentanyl, sevoflurane, and oxygen, heart rate decreases to 20 bpm and 6 premature ventricular contractions per minute are noted. No pulse is detected. The most appropriate next step is to
A 70-kg patient experiences pain on incision of a thigh abscess. The area around the abscess had been infiltrated with 30 ml of 1% lidocaine in 1:200,000 epinephrine. The local anesthetic was most likely ineffective because of
(A) acidosis at the site of the injection
(B) epinephrine-induced limitation of drug diffusion
Which of the following statements concerning carbon monoxide poisoning is true? A 38-year-old woman with a large goiter has undergone subtotal thyroidectomy. Airway obstruction is noted immediately after extubation despite normal vocal cord function on laryngoscopy. Which of the following is the most likely explanation?
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?
(A) Administration of a nitroprusside bolus
(B) Administration of a thiopental bolus
(C) Decrease in rectal temperature from 34°C to 28°C
A tourniquet with dual bladders is being used for intravenous regional anesthesia of the upper extremity. At what point in the procedure should the distal tourniquet be inflated?
(A) During injection of the local anesthetic
(B) After the patient complains of tourniquet pain
(C) Coincident with inflation of the proximal tourniquet
A 30-year-old man who is breathing spontaneously has a ventilatory pattern of sustained deep inspiration and occasional expiratory gasps during emergence from general anesthesia after posterior fossa craniotomy. Which of the following is the most likely cause?
A 4-month-old child undergoing a craniectomy for craniosynostosis is anesthetized with nitrous oxide and halothane. Suddenly the systolic blood pressure decreases from 75 to 30 mmHg, and the PetCO2 decreases from 35 to 6 mmHg. Which of the following maneuvers is LEAST likely to have a beneficial effect?
(A) Administration of a fluid bolus
(B) Administration of a vasopressor
(C) Application of positive end-expiratory pressure
(D) Discontinuation of nitrous oxide
(E) Flooding the surgical wound with saline solution