ORIGINAL ARTICLE Implementation of a Hospital-wide Protocol for Induced Hypothermia Following Successfully Resuscitated Cardiac Arrest Paul M. Szumita, PharmD, BCPS,* Steven Baroletti, PharmD, MBA, BCPS,† Kathleen Ryan Avery, RN,* Anthony F. Massaro, MD,‡ Peter C. Hou, MD,§ Carol Daddio Pierce, RN,¶ Galen V. Henderson, MD, Peter H. Stone, MD,‡** and Benjamin M. Scirica, MD, MPH‡** Abstract: Permanent neurologic impairment following cardiac arrest is often severely debilitating, even after successful resuscitation. Therapeutic hypo- thermia decreases anoxic brain injury and subsequent cognitive deficits. Current practice guidelines recommend therapeutic hypothermia in comatose survivors of cardiac arrest. To address the multifacets of therapeutic hypo- thermia, we assembled a multidisciplinary task force including members from various specialties to create an evidence-based guideline with transpar- ency across disciplines and consistency of care. We describe our institutional guidelines for the initiation and management of induced hypothermia in patients successfully resuscitated from a cardiac arrest. Key Words: hypothermia, cardiac arrest, temperature modulation (Crit Pathways in Cardiol 2010;9: 216 –220) P ermanent neurologic impairment following cardiac arrest is often severely debilitating, even after successful resuscitation. 1 In- creased brain temperature exacerbates the neurologic ischemic dam- age in the period following cardiac arrest. 2 Studies have demon- strated that therapeutic hypothermia decreases anoxic brain injury and subsequent cognitive deficits. 3–5 Randomized controlled trials support the use of mild induced hypothermia (IH) in comatose adults following resuscitation from ventricular fibrillation (VF) cardiac arrest 3,4 and non-VF arrests. 6–8 Current practice guidelines there- fore recommend therapeutic hypothermia in comatose survivors of cardiac arrest. 9,10 We describe our institutional guidelines for the initiation and management of IH in patients successfully resuscitated from a cardiac arrest (Fig. 1). 11 The goal of this guideline is to create a uniform approach at our institution in the optimization of care for these patients. To achieve transparency across disciplines and consis- tency of care within the guideline, we assembled a multidisciplinary task force including members from the following specialties: cardio- vascular medicine, neurology, pulmonary-critical care, emergency medicine, pharmacy, nursing, and cardiac intervention (Fig. 2). PATIENT SELECTION AND TIMING OF INDUCED HYPOTHERMIA The goal of IH is to cool patients for 24 hours with a goal temperature of 32°C to 34°C (90°F–93°F) achieved as early as possible following successful resuscitation. 10 Patients are eligible for the IH protocol if they are comatose, defined by our guideline as: not following commands, no speech, no eye opening, and no purposeful movements to noxious stimuli (equivalent to Richmond Agitation Sedation Scale RASS-4 to -5). Pathologic/posturing movements are permissible. Patients must be successfully resuscitated to a perfusing rhythm fol- lowing cardiac arrest from a nonperfusing rhythm: pulseless ventricular tachycardia [VT], VF, pulseless electrical activity [PEA], and asystole), though they can be started in the protocol if they require vasopressor or inotropic agents or mechanical circulatory support to maintain adequate perfusion. Patients are excluded from the protocol due to physiologic changes that may occur during IH, which may expose them to an excessive risk, specifically hemodynamic instability, impaired co- agulation, suppressed immunity, electrolyte imbalance, and alter- ations in drug metabolism. 12 We thus exclude patients who have suffered recent head trauma, undergone major surgery within the prior 14 days, have suspected sepsis or a systemic infection, and known bleeding diathesis. If there is any evidence or a clinical suspicion for possible head injury with the cardiac arrest, a noncon- trast head computed tomography is recommended prior to initiation or continuation of therapeutic hypothermia. Although data predominately evaluate initiation of cooling within several hours of resuscitation, it is unclear what the thera- peutic timeframe is for initiating cooling. Animal data suggest that the window for benefit may be extended when hypothermia is initiated beyond the initial several hours following resuscitation. 13,14 We recommend IH in comatose patients successfully resuscitated to a perfusing rhythm following cardiac arrest within the preceding 6 hours. However, it may be started as long as 12 hours after resuscitation, at the discretion of treating physicians. INITIATION OF COOLING Following the decision to initiate IH, the goal is to have the patient reach the target temperature as soon as possible. Patients are actively cooled for a 24-hour time period that starts at the initiation of cooling (ie, either in the field by emergency medical service or in-hospital). The IH protocol can be implemented in any intensive care unit, the emergency department, and the cardiac catheterization laboratory. In case of suspected ST elevation myocardial infarction, placement of ice packs or blankets should not delay transfer of patients to the catheterization laboratory. We use a proprietary temperature management system (TMS) and have 1 device for each medical and cardiac intensive care units. TMS offers the benefits of rapid cooling with controlled temperature monitoring, alleviating nursing time, temperature variances, and skin irritation. In most cases, patients will be cooled initially with cooled intravenous saline, ice bags, and then transitioned to TMS, although adequate cooling can be achieved with ice bags and cooling blankets alone. If iced saline has been started by emergency medical service, we recommend it be continued until the infusion is completed. If ice packs have been placed on the patient, their placement is checked for appropriate positions (groin, chest, axilla, and side of neck), and From the *Department of Pharmacy, Brigham and Women’s Hospital, Boston, MA; †Department of Pharmacy, MetroWest Medical Center, Framingham, MA; Departments of ‡Medicine, §Emergency Medicine, ¶Nursing, and Neu- rology, Brigham and Women’s Hospital, Boston, MA; and **Cardiovascular Division, Brigham and Women’s Hospital, Boston, MA. Reprints: Benjamin M. Scirica, MD, MPH, TIMI Study Group, Cardiovascular Division, Brigham and Women’s Hospital, Boston, MA 02115. E-mail: bscirica@partners.org. Copyright © 2010 by Lippincott Williams & Wilkins ISSN: 1535-282X/10/0904-0216 DOI: 10.1097/HPC.0b013e3181f8228d Critical Pathways in Cardiology • Volume 9, Number 4, December 2010 216 | www.critpathcardio.com