A patient has severe pain after total knee arthroplasty. Systemic opioids are most likely to modify the pain through action at which of the following sites?
A 24-year-old woman requires anesthesia for emergency repair of open fractures of the tibia and fibula. She used cocaine two hours ago. Blood pressure is 170/110 mmHg. Each of the following is useful in managing the hypertension EXCEPT
Twenty minutes after an axillary block, the patient reports feeling over the "back of the hand." Examination shows normal sensation over the lateral aspect of the dorsum of the hand and the dorsal base of the thumb and index finger. Supplementary anesthesia of this area can be provided by blocking which of the following nerves?
The following changes occur during posterior cervical fusion in the prone position under halothane and nitrous oxide anesthesia with mechanical ventilation: HR 78 --> 84 with frequent PVCs; BP 110/70 --> 90/50; EtCO2 4.5% --> 2.0%; EtN2 0.12% --> 4% The most appropriate next step is to
A 25-year-old woman is admitted to the hospital in the early stages of labor at term. Initial hematocrit is 33%. Which of the following is the most likely cause of the hematocrit value?
A 76-year-old man has a leaking abdominal aortic aneurysm. His blood pressure and pulse have remained stable for 15 minutes at 90/60 mmHg and 130 bpm, respectively. His hemoglobin concentration is 11 g/dl, and the EKG shows a left bundle branch block. Induction of anesthesia should proceed
(A) after a pulmonary artery catheter has been inserted and the pulmonary artery occlusion pressure is greater than 7 mmHg
(B) when the pulse has decreased below 130 bpm from the rapid transfusion of blood
(C) when systolic blood pressure has increased to more than 120 mmHg from the rapid infusion of lactated Ringer's solution
(D) immediately on arrival in the operating room
(E) when circulatory signs deteriorate or cease to improve with rapid volume expansion
A 2600-g neonate is to undergo surgical repair of a small gastroschisis. The infant is preoxygenated with 100% oxygen. Arterial hemoglobin desaturation is noted during laryngoscopy after a rapid-sequence induction. Which of the following is the most likely cause?
(A) High fetal hemoglobin concentration
(B) High ratio of oxygen consumption to functional residual capacity
(C) Low functional residual capacity in milliliters per kilogram