A healthy 10-kg child is flushed and restless after premedication with meperidine 15 mg and scopolamine 0.2 mg intramuscularly. His skin is warm and dry; temperature is 38°C, pulse is 130 bpm, and blood pressure is 90/60 mmHg. The most likely cause is
A 70-year-old man undergoes cross clamping of the aorta for repair of an abdominal aneurysm. Which of the following methods is most appropriate for decreasing hypotension associated with removal of the cross clamp?
(A) Administration of a phenylephrine bolus when the cross clamp is removed
(B) Correction of any base deficit with sodium bicarbonate during clamping
(C) Decrease of anesthetic to allow blood pressure to increase to 20% above preclamp levels
(D) Volume loading to increase pulmonary artery occlusion pressure prior to removal
(E) Infusion of dopamine 10 minutes prior to removal
A patient whose trachea is intubated develops partial airway obstruction two hours after induction of fentanyl, nitrous oxide, oxygen anesthesia. The anesthesiologist discontinues the nitrous oxide and controls ventilation, and there is gradual improvement during the next hour. No evidence of a respiratory disorder is found at the conclusion of the anesthetic. Which of the following is most likely?
(A) The endotracheal tube was in the right mainstem bronchus
(B) The patient had an unrecognized air embolism
(C) The patient had a nitrous oxide pneumothorax
(D) The endotracheal tube cuff narrowed the airway
The primary mechanism for respiratory arrest following a spinal anesthetic to T2 is
(A) block of carotid chemoreceptors
(B) direct effect of local anesthetic on the medulla
(C) ischemia of respiratory centers in the medulla
(D) paralysis of the diaphragm by neural block
(E) paralysis of intercostal muscles
C
An axillary block is administered to a 60-kg patient using 40 ml of 0.5% bupivacaine. Ten minutes after placement of the block, the patient has a seizure. Which of the following statements is true?
(A) A low serum albumin concentration could have contributed to the occurrence of the seizure
(B) CNS hypoperfusion is the most likely cause of the seizure
(C) The seizure was probably secondary to an allergic reaction to the local anesthetic
(D) The use of an equipotent dose of lidocaine rather than bupivacaine would have decreased the likelihood of
Pulmonary artery diastolic pressure increases acutely from 10 to 20 mmHg in a 28-year-old man undergoing cervical laminectomy in the sitting position. The most appropriate first step in the management of this patient is to
(A) administer furosemide
(B) aspirate from the proximal port of the pulmonary artery catheter
(C) inflate the balloon on the pulmonary artery catheter
(D) place the patient in the left lateral decubitus position
(E) start an infusion of nitroglycerin
B
A woman at 39 weeks' gestation has been in labor for 12 hours. She has had nausea and vomiting for the past eight hours. Maternal arterial blood gas values are PaO1 85 mmHg, PaCO2 31 mmHg, and pH 7.50. Which of the following is the most likely cause of fetal distress occurring at this time?
(A) Hypocarbia-induced placental ischemia
(B) Impaired fetal oxyhemoglobin dissociation
(C) Shift to the left of the maternal oxyhemoglobin dissociation curve
During induction of anesthesia, a 56-year-old man with small bowel obstruction vomits a large quantity of undigested food particles and presumably aspirates. After instituting ventilation with pure oxygen, the most appropriate management is to
(A) administer dexamethasone
(B) administer penicillin G
(C) perform bronchoscopy
(D) ventilate with positive end-expiratory pressure 15 cmH2O
(E) proceed with the anesthesia plan if the tracheal pH is greater than 2.5