SAEM Emergency Medicine Exam with Questions and Answers

SAEM Emergency Medicine Exam with Questions and Answers The next step in treatment for a patient with ventricular fibrillation, which is refractory to multiple countershocks and epinephrine, is: A. calcium B. transcutaneous pacing C. adenosine D. lidocaine E. bicarbonate ANSWER The answer is D. Ventricular fibrillation is primarily treated with defibrillation. If three successive shocks and epinephrine have been given, the next line agent would be an antiarrhythmic, such as lidocaine or amiodarone. Which of the following is the treatment of choice for torsades de pointes? A. defibrillation B. sodium bicarbonate C. external pacing D. lidocaine E. magnesium sulfate ANSWER The answer is E. Torsades de pointes is a form of ventricular tachycardia in which the QRS morphology twists around the baseline. It may occur spontaneously in the setting of hypokalemia, hypomagnesia, or any drug that prolongs the QT interval. Magnesium best controls it. If that fails, try overdrive pacing. The unstable patient should be cardioverted when the rhythm is sustained, but cardioversion is not likely to have sustained success in the absence of adjunctive therapy (e.g. magnesium). A 60-year-old male is brought in by paramedics after a witnessed cardiac arrest. He remains pulseless and apneic. Rhythm strip is shown below. In addition to providing effective cardiopulmonary resuscitation, what management step is most likely to result in survival?