A 20-year-old man with a history of substance abuse is undergoing preoperative evaluation. Which of the following findings suggests current use of cocaine?
A 69-year-old man is confused and agitated one hour after preoperative intramuscular administration of scopolamine for awake fiberoptic laryngoscopy. SpO2 measured by pulse oximetry is 97%. Which of the following drugs is most appropriate for treatment of the change in mental status?
A 45-kg, 80-year-old woman undergoes pin fixation of the right hip in the lateral decubitus position under spinal anesthesia. One day after the operation, she cannot move her left ankle or foot actively. The most likely cause is
A 68-year-old man with stable angina treated with propranolol and nifedipine is scheduled for coronary artery bypass grafting. After induction with fentanyl and tracheal intubation, heart rate decreases to 40 bpm and blood pressure decreases to 70/40 mmHg. The ECG is shown. Which of the following is the most appropriate first step in management?
(A) Infusion of isoproterenol
(B) Administration of phenylephrine
(C) Closed chest cardiopulmonary resuscitation
(D) Defibrillation
(E) Synchronized cardioversion
A
Ten minutes after induction of anesthesia with thiopental and isoflurane but before incision, a patient's nasopharyngeal temperature has decreased to 35.4°C. Which of the following contributed most to this decrease in temperature?
(A) Anesthesia-induced block of nonshivering thermogenesis
When using apneic oxygenation during endoscopy in a normothermic patient, PaC02
(A) increases at a rate inversely proportional to oxygen flow rate
(B) increases at a rate of 8 + 0.5 mmHg per minute
(C) increases at the same rate that Pa02 decreases
(D) equals mixed venous PC02 after one minute
(E) is increased by airway obstruction
D
A 55-year-old man who is scheduled to undergo carotid endarterectomy (CEA) has a persistent myocardial filling defect at three hours on a dipyridamole-thallium scan. Which of the following statements is correct?
(A) Coronary autoregulation is effective in this segment
Arterial pressure in the radial artery is 155/70 mmHg measured by a correctly calibrated catheter-transducer system. At the same time aortic pressure is 140/75 mmHg using a high-fidelity catheter tip transducer. The most likely cause of this discrepancy is
(A) a large amount of air in the dome of the radial artery transducer
(B) coarctation of the aorta
(C) peripheral vascular constriction produced by sympathetic stimulation
(D) physiologic amplification of the wave form from the aorta to the radial artery
(E) too high a frequency response in the catheter-transducer system