In a 5-kg child, the end-tidal carbon dioxide tension is 35 mmHg during spontaneous ventilation through a Mapleson D system. Which single change is most likely to increase this value?
Which of the following is the most common infection transmitted through transfusion of blood products?
(A) Epstein-Barr virus
(B) Hepatitis B
(C) Hepatitis C
(D) Human immunodeficiency virus
(E) Toxoplasmosis
B
A 52-year-old man develops oliguria 24 hours after left hemicolectomy. Urinalysis shows a specific gravity of 1.028, an osmolality of 650 mOsm/L, and a sodium concentration of 10 mEq/L. Which of the following is the most likely diagnosis?
(A) Acute tubular necrosis
(B) Hypoaldosteronism
(C) Hypovolemia
(D) Interstitial renal disease
(E) Obstructive uropathy
C
When used with morphine for premedication, which of the following drugs is most likely to cause sedation?
One week after sustaining third-degree burns over 40% of his body surface area, a patient requires general anesthesia for debridement and skin grafting. Which of the following responses to neuromuscular blockers is most likely?
(A) Clinically insignificant increases in serum potassium concentration after administration of succinylcholine 1 mg/kg
(B) Increased risk of hyperkalemia after administration of succinylcholine 1 mg/kg
(C) Increased sensitivity to vecuronium
(D) Laudanosine toxicity after administration of atracurium 0.4 mg/kg
(E) Normal serum potassium concentration if administration of succinylcholine is preceded by d-tubocurarine 3 mg
A 6-year-old boy undergoes craniotomy in the supine position for brain tumor during anesthesia with 1.5% isoflurane in oxygen. PetCO2 is 38 mmHg, heart rate is 78 bpm, and blood pressure is 130/80 mmHg. After opening the dura, the surgeon notes that the brain is bulging. Which of the following management options is LEAST likely to significantly decrease brain size?
A 72-year-old woman with stable angina is undergoing bowel resection. Anesthesia is induced with etomidate. Five minutes after starting isoflurane 1% in nitrous oxide 50%, her blood pressure decreases from 110/84 to 70/40 mmHg. The most likely cause is
(A) coronary steal produced by isoflurane
(B) direct myocardial depression produced by isoflurane
(C) vasodilation produced by isoflurane
(D) adrenocortical suppression produced by etomidate
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
A child has tachypnea immediately after reintubation for intractable laryngospasm. Oxygen saturation is 78% at an FiO2 of 1.0. A radiograph of the chest taken 15 minutes later is most likely to show
(A) bilateral pleural effusions
(B) diffuse homogenous pulmonary infiltrates
(C) patchy central infiltrates of the right upper lobe