Folder: Subfolder: Title: Original Effective Date: Approved by Group/committee: Date(s) Revised: Date(s) Reviewed: Joint Commission Chapter and Year: Other Flags: Emergency Department/Critical Care Management of the Patient Receiving Mild Therapeutic Hypothermia after Cardiac Arrest 3/2010 Critical Care Committee Emergency Department Leadership 4/2010 Joint Commission Chapter: JCAHO Standard PC3.130 Cardiac Arrest, Hypothermia Purpose: The purpose of this protocol is to guide the medical and nursing staff in the appropriate management of the patient receiving mild therapeutic hypothermia (MTH) following a cardiac arrest. Equipment: Cold (4˚C) normal saline (from Trauma refrigerator) Naso/oro gastric tube Esophageal temperature probe Thermometer External cooling blankets Endovascular cooling device Ice packs Towels Background/Supportive Data: Brain temperature during the first 24 hours after resuscitation from cardiac arrest may have a significant effect on survival and neurological recovery. Cooling the patient to 3234 °C for 24 hours decreases the chance of death and increases the chance of neurological recovery. 1. Review patient eligibility a. Inclusion Criteria: 1. Age greater than 21. 2. Cardiac arrest defined as: documented pulselessness in a patient who received cardiopulmonary resuscitation (CPR) regardless of initial cardiac rhythm. 3. The patient has return of spontaneous circulation (ROSC). 4. Less than 6 hours since ROSC. 5. The patient is comatose at the time of cooling. (Comatose is defined as: not following commands, no speech, no eye opening, no purposeful movements to noxious stimuli1. Brainstem reflexes and pathological/posturing movements are permissible. Sedative or paralytic medications should be unnecessary during the evaluation.) CP/IB 2008 Draft updated 4/26/2010 6. Out-of-hospital cardiac arrest: presumed cardiac etiology. 7. In-hospital cardiac arrest: unexpected ventricular fibrillation/tachycardia cardiac arrest. For post surgical patients, discretion will be left to the primary surgeon. 8. Negative Head CT if presumed head injury. 9. Pre-arrest cognitive status not severely impaired (ie: able to perform ADL independently). 10. No evidence of uncontrolled dysrhythmias or untreated complete heart block. Exclusion Criteria: 1. Age less than or equal to 21 years. 2. Pregnancy. 3. Presumed non-cardiac cause for arrest: i.e. trauma, stroke, poisoning, sepsis, and seizure. 5. Known severe coagulopathy history or significant active bleeding. (Anticoagulation, antiplatelet agents, and thrombolytics [TPA] are not contraindicated.) 6. Patient has valid Do Not Resuscitate/Intubate order. 7. Pre-existing multisystem organ failure 8. Prolonged down time is not an absolute contraindication but resuscitation time of less than 1 hour is recommended. 2. Pre-Induction Activate “Code Chill” by calling hospital operator 1. This will notify the ICU screener, CCU charge nurse, Neurology resident, Nursing supervisor, Respiratory therapist, Pharmacy, Admitting. 2. For private patients, the attending will notify requested cardiologist and intensivist. For service patients, the ICU screener will notify the UCG fellow and appropriate cardiologist and intensivist. 3. Patients will be admitted to the CCU. a. Mandatory Organ Sharing Network notification within 60 minutes of arrival. 1. To facilitate early identification of potential donors, all ventilator dependent patients (regardless of age, diagnosis, sedation or religious beliefs) will be referred to the NJ Sharing Network by the primary nurse. 2. Ideal referral will be within 1 hour of arrival, but no longer than two hours of meeting the following clinical triggers: a of GCS of 5 or less, or the loss of two or more of the following reflexes: gag, cough, pupils, corneal, respiration, or response to pain. b. Mandatory Critical Care Consult with initiation of hypothermia. c. Mandatory Neurology consult within 12 hours to help facilitate EEG monitoring for seizure activity during cooling. d. Establish and secure an airway. 1. Maintain the patient on mechanical ventilation without warm humidified oxygen. 2. Maintain PaO2 of 100 mmHg and a PaCO2 of 40 mmHg. e. Obtain a stat 12-lead EKG. 1. Analyze electrocardiogram (EKG). CP/IB 2008 Draft updated 4/26/2010 If the EKG is suggestive of ST elevation myocardial infarction (STEMI), proceed with current Code MI protocol. MTH may be considered, but should not delay transport to the CATH lab. Ensure discussion with interventional cardiologist as per Code MI protocol, but if cold fluid and/or line placement are requested prior to catheterization consider placement location. 2. If an anti-arrhythmic is needed consider administration of Amiodarone. 3. If the patient’s history and EKG are suggestive of acute coronary syndrome without MI, administer anticoagulation as appropriate. f. Apply continuous cardiac monitoring. g. Apply continuous pulse oximetry. h. Establish at least 2 large bore IVs of size 18g or greater. i. Maintain mean arterial pressure (MAP) 80-100 mmHg to help maintain adequate cerebral perfusion. If evidence of CHF, ACS or Shock use lower range of MAP (80-100 mmHg) and may even require a goal MAP as low as 65 mmHg, depending on the degree cardiac dysfunction. If patient is showing signs of CHF/Pulmonary Edema stop fluid infusion and call MD. 1. Vasopressors, inotropes, nitrates, and fluid bolus may be used as indicated. 2. Consider a lower MAP goal if clear CHF or acute coronary syndrome. j. Administer appropriate pain control. k. Administer appropriate sedation. l. Administer appropriate neuromuscular blockade for shivering prevention. Single initial dose of vecuronium preferred; titrate future doses to maintain 2/4 with train-of-four monitoring. m. Insert an oral gastric tube and connect it to continuous low wall suction. n. Administer aspirin per OGT to all patients unless contraindicated. o. Check glucose. 1. If not known diabetic and initial glucose level was within target of 100150 mg/dl, recheck every 4 hours. 2. If known diabetic or not within target of 100-150 mg/dl, recheck every 2 hours. 3. If greater than 150 mg/dl, consider insulin bolus or drip as appropriate. p. Draw and send appropriate labs including ABG, CMP, CBC, LFTS, PT/INR, PTT, Type & Screen, Lactate, Cardiac enzymes. q. Vital signs (Temperature, Pulse, Respirations, Blood Pressure and Pulse Oximetry) should be recorded at a minimum of every 15 minutes for 2 hours, then every 30 minutes for 4 hours and hourly thereafter. r. Notify MD for any dysrhythmia or heart rate less than 50 beats/min. s. Insert temperature sensing Foley catheter, if unavailable or contraindicated, the physician will insert an esophageal temperature probe. t. Record hourly I&O. u. Insert an A-line as soon as possible, preferably before MTH initiation. Radial location preferred. v. Obtain baseline temperature. 3. Hypothermia Induction a. All Patients 1. Document time that cooling is initiated. CP/IB 2008 Draft updated 4/26/2010 2. Infuse intravenously 1500-2000 ml of cold (4 ºC from the refrigerator) 0.9% NaCL bolus over a period of 20 minutes unless clear contraindication of pulmonary edema. If known cardiomyopathy may consider reduced fluid bolus. 3. Close the door to the patient’s room and set thermostat in the patient’s room as close to 60 oF if possible. 4. Remove all clothing and apply a hospital gown. 5. Cover hands/feet in dry towel to prevent thermal injury. 6. Notify MD immediately if shivering occurs during induction. Titrate neuromuscular blockade. 7. Monitor the patient for hypothermia-related diuresis. Consider 1:1 fluid replacement with cold 0.9% NS or Lactated Ringers. If known cardiomyopathy the 1:1 fluid replacement should include the current volume of all infusions. 8. Replace electrolytes as needed. Maintain serum potassium between 3.2 and 3.5 mEq/L. Anticipate a rise in potassium as warming occurs. b. Endovascular Cooling 1. Obtain KUB to ensure that an IVC filter is not present. 2. The MD will insert an endovascular cooling catheter via femoral site as long as an IVC filter is not present. If immediate cardiac catheterization is anticipated, discuss placement location with interventional cardiologist. Consider fluoroscopy guidance if filter present and difficulty anticipated. 3. Catheters may be inserted in the ED, ICU, and cath lab. 4. Set up endovascular cooling module according to manufacturer’s specifications. Set goal temperature as 33.0 ºC [91.4 ºF] (for target temperature range 33-34 ºC [91.4-93.2 ºF]) and cooling rate “maximum.” 5. Note: ports on endovascular catheters can be used for routine central line functions, including CVP measurement except administration of mannitol due to temperature dependent crystallization. 6. Use caution if any catheter must be placed above the diaphragm if baseline temperature is less than 32 °C [89.6 ˚F] due to risk of ventricular ectopy. c. Surface Cooling (if endovascular cooling device not available) 1. Apply cooling blanket below and above patient with sheets between blankets and patient. Skin is NOT to come in direct contact with cooling blankets. 2 Apply ice packs wrapped in towels to the axillae, groin, and sides of neck. 3. Remove ice packs and stop cold saline once temperature is less than or equal to 34 ºC [93.2 ºF]. 4. Consider turning off cooling blanket temporarily to avoid temperature overshoot. 5. Complete skin assessment at a minimum of every 2 hours. 6. During rewarming using auxiliary surface cooling, slowly discontinue cooling blanket or consider setting water temperature in cooling blanket to 35 °C and slowly increasing the water temperature by 0.5 °C every 2 hours until CP/IB 2008 Draft updated 4/26/2010 a stable core body temperature of 36 °C has been reached. Do not warm faster than 0.5 °C/hour. 4. Hypothermia Maintenance 1. Record the exact time that the core temperature first reaches the target range (less than or equal to 34 ºC [93.2 ºF]) on the nursing flow sheet. 2. Maintain core temperature 33-34 ºC [91.4-93.2 ºF] for 24 consecutive total hours starting from initiation of cooling. 3. If temperature falls below 32.2 °C [90.0 ºF], notify MD immediately. 4. Continue 1:1 urine output replacement with cold 0.9%NS.Avoid potassium repletion within 6 hours of anticipated rewarming as potassium will shift back out of cells and hyperkalemia may result. 5. Nutrition therapy should be held during the initiation or maintenance phase of therapy due to reduced metabolism and preferential shunting of blood to other organs. Re-warming a. All Patients 1. After 24 hours total of hypothermia, re-warm at no more than 0.5 ºC/hour. 2. Record all vital signs at a minimum of every 30 minutes during rewarming. 3. Set ambient room temperature to 68 ˚F degrees. 4. Maintain neuromuscular blockade until temperature reaches 36 ºC [96.8 ˚F]. 5. Potassium administration including any mixed fluids should be stopped as potassium may increase during rewarming. Monitor potassium every 6 hours for 24 hours post warming. 6. Notify MD once temperature returns to 36 °C [96.8 ˚F]. 7. As temperature increases, peripheral vasculature may dilate. Maintain MAP greater than 80 mm Hg. 8. Monitor glucose every 2 hours during re-warming. 9. Once the patient has reached target temperature the console may be placed on “Standby” and utilized for monitoring temperature for up to a total of 72 hours. 10. If within the 72 hours that the catheter is in place the console may be utilized in the fever control mode and set target temperature at 37.5. After 72 hours the tubing must be discarded. If the patient becomes febrile after cooling catheter is removed, traditional water circulating cooling blanket should be used to treat fever, which is often unresponsive to acetaminophen. 11. Stop the 1:1 urine replacement if the patient is hemodynamically stable and maintaining a urine output of at least 1cc/kg/hour or as dictated by the patient’s condition. b. Endovascular Cooling 1. Set the cooling catheter apparatus to 36.5 °C with a “controlled rate” of 0.3 °C/hour. CP/IB 2008 Draft updated 4/26/2010 2. Endovascular cooling in combination with antipyretics may be used to ensure normothermia (strict avoidance of hyperthermia) over the next 12 hours. The catheter should be removed within 72 total hours of placement. 5. Supportive Care/Special Considerations a. Resource personnel are available to help staff with questions related to the protocol and for trouble shooting of the equipment. These resources are not directly placing orders and all orders are to be discussed with the critical care attending as usual and the appropriate cardiologist. The attending of record is responsible for the management of the patient. In the event there is a discrepancy in the care of the patient the medical director of the respected unit should be notified. b. Administer appropriate stress ulcer prophylaxis. c. Deep venous thrombosis prophylaxis as appropriate. d. Keep head of bed elevated at 30˚ to prevent aspiration by using reverse trendelenberg) in order to prevent kinking of the catheter. e. Patients should NOT have sedation holiday during MTH protocol. f. Complete serial EKGs every 8 hours x 3, then daily. g. Avoid bathing patient during hypothermic or rewarming period. h. Lab Work: CMP, CBC, PT/PTT/INR, ABG, cardiac enzymes, lactate every 8 hours x 3, then daily. i. If patient has not regained any neurological function at 72 hours after initiation of MTH, consider evaluation for brain death (Refer to the policy “Declaration of Death upon the Basis of Neurological Criteria”). Please note there are reports of patients awakening after 72 hours due to slowed metabolism of sedation medication, etc. Prognostication prior to 72 hours is considered unreliable. j. If burst or sz activity is noted on EEG, treatment with ativan, keppra, depakote, lamictal, zonegran, or topamax, can be considered depending upon the clinical situation although this commonly represents prior anoxic neural injury and is poorly responsive to therapy. k. Nutrition should be considered as soon as the patient becomes normothermic. l. MTH can inhibit CP450 metabolism; increase plasma concentration of Midazolam, Propofol, and Fentanyl; and increase the duration of action of Vecuronium. In animal studies, however, morphine’s potency and affinity for mu receptors declined, requiring higher doses for desired analgesia2. m. If appropriate or indicated the distal port of the catheter may be used to transducer CVP (during hypothermia the CVP may be artificially elevated) or a ScVO2 specimen. n. Lacrilube should be applied to each eye every 8 hours and prn while paralyzed. o. Forehead pulse oximeter with a fingertip sensor may be inadequate, so frequent ABG’s may be indicated. p. Apply Prafo boots/high top sneakers while paralyzed to prevent foot drop. 6. Monitoring for Complications a. Monitor patient for potential complications and document any of the following for 72 hours from initiation of MTH. CP/IB 2008 Draft updated 4/26/2010 1. Bleeding: any clinically significant bleeding requiring transfusion, or hemoglobin concentration drop greater or equal to 2 g/dl. 2. Cardiac arrhythmia: any cardiac arrhythmia requiring treatment with an anti-arrhythmic agent or cardioversion. 3. Infection: any new infection requiring initiation of antibiotic therapy. 4. Temperature overshoot: body temperature less than 32 ºC [89.6 ˚F] for more than 1 hour in duration3. 7. Reasons for early discontinuation of MTH. a. If the patient develops any of the below conditions thought to be related to cooling, the cooling devices need to be discontinued immediately and the patient will be allowed to passively re-warm. 1. Ventricular tachycardia or ventricular fibrillation. 2. Asystole. 3. Sustained SVT. 4. Refractory hypotension despite 2 vasopressors and not an intra-aortic balloon pump (IABP) candidate. . 8. Performance Improvement a. Each case will be reviewed as part of an ongoing process by multidisciplinary Therapeutic Hypothermia working group. 9. Education: a. Families and next of kin should be provided with education as appropriate. References: 1. 2. 3. Giacino JT. Disorders of consciousness: differential diagnosis and neuropathologic features. Semin Neurol. Jun 1997;17(2):105-111. Tortorici MA, Kochanek PM, Poloyac SM. Effects of hypothermia on drug disposition, metabolism, and response: A focus of hypothermia-mediated alterations on the cytochrome P450 enzyme system. Crit Care Med. Sep 2007;35(9):2196-2204. Merchant RM, Abella BS, Peberdy MA, et al. Therapeutic hypothermia after cardiac arrest: unintentional overcooling is common using ice packs and conventional cooling blankets. Crit Care Med. Dec 2006;34(12 Suppl):S490-494. CP/IB 2008 Draft updated 4/26/2010