A patient with chronic paraplegia (T4 level) is undergoing cystoscopy and removal of bladder calculi without anesthesia. After 10 minutes, blood pressure is 240/100 mmHg and pulse is 50 bpm. The most appropriate management is administration of
A 6-year-old boy with spina bifida and a chronic indwelling urinary catheter has severe hypotension and hypoxemia during augmentation cystoplasty. Which of the following is the most likely cause?
(A) Autonomic neuropathy
(B) Disseminated intravascular coagulation
(C) Latex allergy
(D) Urinary sepsis
(E) Venous air embolism
C
A 67-year-old man is undergoing total hip replacement under general anesthesia. He had a permanent endocardial VVI pacemaker placed two years ago for complete heart block, and since arrival in the operating room has been paced continuously. Use of the electrocautery causes the pacemaker to malfunction intermittently. The most appropriate management is to
(A) tape a magnet over the pacemaker generator and convert to asynchronous mode
(B) do nothing since the pacemaker is programmed to deal with this circumstance
(C) stop the surgeon from using the electrocautery
(D) limit the surgeon to 10 sec/min electrocautery bursts
(E) place the electrocautery indifferent lead as close as possible to the pacemaker
(D) Inhibiting sodium ion influx across the neuronal cell membrane
(E) Opening sodium channels at the nodes of Ranvier
D
A 64-year-old patient with chronic obstructive pulmonary disease sustained fractures of ribs 4 through 8 on the left one hour ago. Examination shows agitation, heart rate of 120 bpm, respiratory rate of 30/min, and blood pressure of 180/100 mmHg. PaO2 is 70 mmHg and PaCO2 is 35 mmHg on room air. Radiographs of the chest show no abnormalities. Which of the following is the most appropriate immediate management?
(A) Continuous epidural analgesia using local anesthetics
(B) Mechanical ventilation
(C) Infusion of midazolam
(D) Patient-controlled analgesia with morphine sulfate
An 87-kg 64-year-old woman in good general health is undergoing a right knee arthroplasty while in the supine position with general anesthesia consisting of enflurane 2% and nitrous oxide 50% in oxygen. She is breathing spontaneously through a 7-mm endotracheal tube. During the first 30 minutes of the procedure, the arterial oxygen saturation measured by pulse oximetry decreases from 98% to 92%. The most likely cause of the desaturation is
(A) decreased functional residual capacity
(B) diffusion hypoxia
(C) hypercarbia
(D) increased airway resistance produced by the endotracheal tube
(E) inhibition of hypoxic pulmonary vasoconstriction
A
A 2.3-kg 1-day-old term infant requires repair of a gastroschisis. Which of the following combinations is most appropriate for intraoperative fluid management?
(A) Dextrose 5% in water for maintenance and lactated Ringer's solution for replacement of third space losses
(B) Dextrose 10% in water for maintenance and lactated Ringer's solution for replacement of third space losses
(C) Lactated Ringer's solution for maintenance and replacement of third space losses
(D) Lactated Ringer's solution for maintenance and albumin 5% for replacement of third space losses
(E) Normal saline solution for maintenance and lactated Ringer's solution for replacement of third space losses
A 45-year-old woman with mitral stenosis is scheduled for elective mitral valve replacement. Two minutes after tracheal intubation, she develops atrial fibrillation with a ventricular response rate of 150 bpm and a decrease in blood pressure to 75/45 mmHg. Which of the following is the most appropriate first step in management?
(A) Increasing the concentration of enflurane
(B) Increasing the infusion rate of lactated Ringer's solution