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
(C) Intravenous administration of digoxin
(D) Intravenous administration of propranolol
(E) Electrical cardioversion
E
A patient has severe hypotension, bronchospasm, and edema of the upper airway after injection of radiocontrast medium during cerebral angiography. The most appropriate immediate treatment is administration of
A patient has fever and chills in the recovery room following an abdominal hysterectomy that required the intraoperative administration of whole blood 1 unit. A blood sample drawn in the recovery room shows no free hemoglobin. Subsequently, packed red blood cells 1 unit and fresh frozen plasma 1 unit are administered, and the fever and chills recur. The most likely cause of the fever and chills is
(A) an allergic-type transfusion reaction
(B) a hemolytic transfusion reaction to untested antibodies
(C) bacterial contamination of blood
(D) a reaction to leukocytes contained in the plasma
(E) the presence of cold agglutinins in the patient
D
A 30-year-old woman is undergoing laparoscopic tubal ligation. Thirty minutes after induction of general anesthesia, arterial oxygen saturation has decreased to 89%. Arterial blood gases at an FiO2 of 1.0 are PaO2 63 mmHg and PaCO2 40 mmHg; PetCO2 is 32 mmHg. Which of the following is the most likely cause?
(A) Carbon dioxide embolus
(B) Endobronchial intubation
(C) Hypoventilation
(D) Inadvertent application of high levels of positive end-expiratory pressure