GENERAL MEDICINE/CASE REPORT Successful Transcutaneous Pacing in 2 Severely Hypothermic Patients Jeffrey D. Ho, MD William G. Heegaard, MD Douglas D. Brunette, MD From the Department of Emergency Medicine, Hennepin County Medical Center, and the Emergency Medicine Program, University of Minnesota Medical School, Minneapolis, MN. The clinical condition of profound hypothermia is well described in the medical literature. There have been many case reports and studies describing successful aspects of caring for this problem. Significant bradycardia is a known pathophysiologic consequence of profound hypothermia. Transcutaneous pacing for this condition is not a routine or recommended practice in the literature. This case report details 2 patients with profound hypothermia and resultant bradycardia with hypotension. In both cases, transcutaneous pacing was successfully applied and used as part of the resuscitation. In both cases, transcutaneous pacing was required to maintain an adequate blood pressure so that continuous arteriovenous rewarming could be used during the resuscitation. Both cases had successful outcomes, and the rewarming process was greatly assisted by the pacing procedure. [Ann Emerg Med. 2007;49:678-681.] 0196-0644/$-see front matter Copyright © 2007 by the American College of Emergency Physicians. doi:10.1016/j.annemergmed.2006.05.014 INTRODUCTION Severe hypothermia is classically defined as a body temperature less than 30°C (86°F). Cardiac arrhythmia and irritability as a result has been well described in such cases. Accepted treatment includes rapid rewarming practices, cardiopulmonary resuscitation (CPR) as necessary, and limited medications and defibrillation in cardiac arrest situations. Transcutaneous pacing is not a routine or recommended practice in severely hypothermic patients with hypotension and bradycardia. In this report, we describe 2 patients with profound hypothermia, bradycardia, and hypotension who responded well to transcutaneous pacing. Both patients survived, with excellent clinical and neurologic outcome. CASE REPORT Case 1 On a midwinter afternoon, we received an unresponsive 80-year-old man in our emergency department (ED). He was found by a concerned neighbor who went to check on him because she had not seen him that morning as usual. He had last been seen 48 hours earlier and was reported to have no medical complaints at that time. The neighbor found the back door to the home unlocked and open, with the patient lying face down in the kitchen area. Because of the open door, the kitchen area was fully exposed to the external elements. The neighbor found the patient prone and noticed his eyeglasses to be broken and lying beside him. She rolled him on to his back and found him to be very cold to the touch. She called 911 immediately, and when emergency medical services (EMS) arrived, they found the patient to have no discernible blood pressure, with cardiac electrical activity at a sinus bradycardic rate of 30 beats/min. His respiratory rate was spontaneous but labored at 12 breaths/min. Pulse oximetry was unobtainable. The patient was administered high-flow oxygen, an intravenous line was established, and 0.5 mg of atropine was administered per protocol, which resulted in the patient’s cardiac rate increasing to 40 beats/min but still without a palpable pulse or blood pressure. The patient also had a nasopharyngeal airway placed en route to the hospital. On arrival, the patient was taken to our resuscitation area immediately. A primary survey was conducted, and the patient was noted to occasionally moan. His airway was clear. He had equal breath sounds. We were unable to auscultate heart tones. He did have a bradycardic rhythm on the cardiac monitor that perfused with weak, intermittent carotid and femoral pulses at a rate of 22 beats/min. There was occasional spontaneous movement of his extremities, but it was not purposeful. On secondary survey, his blood pressure remained unobtainable. His head had some abrasions around the nose and on the scalp. His pupils were 1 mm and nonreactive. He had some dried blood around his right naris. His tympanic membranes were unable to be visualized, because of cerumen impaction. He was in a cervical spine protection collar per EMS. His lungs were clear to auscultation, his heart tones remained inaudible, and his abdominal examination result was 678 Annals of Emergency Medicine Volume , .  : May 