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Microsoft powerpoint - therapuetic induced hypothermia.ppt

Therapeutic Hypothermia Annmarie Keck RN, CEN, EMT-B Clinical Outreach Educator

History of Hypothermia Baron Dominique Jean Larrey, a surgeon in the Napoleonic army who invented the "flying ambulance" to rapidly rescue wounded soldiers from the field, described that during the Napoleonic wars wounded soldiers who were put close to a campfire died earlier than those who were not re-warmed.

Dog Studies-Safar Center Dr Peter Safar editorial 2002 Safar Center for Resuscitation Research University of Pittsburg PA - 1994 5 outcome studies in dogs that documented for the first time after normothermic cardiac arrest, the ability of mild hypothermia to reduce brain damage. "It was the dog outcome data that led to the positive randomized clinical outcome studies in Europe and Australia published in NEJM Feb. 2002." Annals Emergency Medicine Vol 41:6 p 887 – 888 June 2003

1. Bernard SA, Gray TW Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia NEJM 2002;346:557-563, Australia Results: 49% vs 26%, hypo vs normo, had a "good outcome" - as defined by discharge to home or rehab 2. Hypothermia After Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest NEJM 2002;346:549-556 Results: 55% vs 39%, hypo vs normo, had a CPC-cerebral performance category score of "good recovery" or "moderate disability"

ILCOR Advisory Statement-Oct ‘02 "Unconscious adult patients with spontaneous circulation after out-of-hospital cardiac arrest should be cooled to 32C to 34C for 12-24 hrs when the initial rhythm was ventricular fibrillation." Nolan, et al., Circulation July 8th 2003 p 118 – 121 • Apotosis vs Necrosis • Reperfusion injury • Inflammatory response • Free radicals "Cool Under Pressure" The Spokesman Review Friday Jan 23rd 2004 A 44 y/o fm comatose after apparent MI on January 12th associated with cardiac arrest, and resultant coma.
Transported from City of Sprague to Deaconess E.D.
Dr. James Nania, Dr. Pierre Leimgruber and Dr. Dan Coulston and the fine nursing staff of the Deaconess ED and CICU The patient awoke after nearly 48 hours • Without measurable neurological deficits • no memory for the day of the heart attack.
It took 7 defibrillations – some with an AED, and some in the ambulance en route to Deaconess.
DMC's Manual protocol External cooling will be initiated in ED by RN to include: Initiation with ice packs on patient's axilla and groin until cooling blankets started.
Lay single layer sheet on top of each cooling blanket.
Wrap patient in 2 cooling blankets/ sheets (sheet side to patient) by "log rolling" patient—one blanket wrapped around torso and the other around the pelvis and legs.
he "MANUAL" mode on cooling machine and set the
set point temperature on the cooling unit to 5 degrees C.
Once patient temperature of 33 degrees C is achieved, select the "AUTO" mode on the cooling machine
2006 Overcooling • Therapeutic hypothermia after cardiac arrest: Unintentional overcooling is common using ice packs and conventional cooling blankets-sponsored by Alsius Merchant, Raina M. MD; Abella, Benjamin S. MD, MPhil; Peberdy, Mary
Ann MD; Soar, Jasmeet MD; Ong, Marcus E. H. MBBS, MPH; Schmidt,
Gregory A. MD; Becker, Lance B. MD; Vanden Hoek, Terry L. MD
Issue:Volume 34(12) Suppl, December 2006, pp S490-S494
• Shows two different patients temp graphs • Alsius-intravascular cooling catheter used at DMC beginning in 2006 • Arctic Sun-external cooling pads used by Providence Sacred Heart Jan 2007, Kadlec Medical Center, Central Washington Hospital, Kootenai Medical Center Artic Sun-Medivance • Non-Traumatic cardiac arrest with return of spontaneous
circulation (ROSC) but remains unconscious • Patient > 16 years of age• Initial temperature > 34° C (93.2 °F)• Patient remains comatose (no purposeful response to pain)• Patient must be intubated to initiate protocol.
• If patient meets other criteria for induced hypothermia and is not intubated, then intubate according to protocol before induced cooling. • If unable to intubate DO NOT initiate induced hypothermia.
• Initiated within 3 hours of cardiac arrest
• If there is loss of spontaneous circulation after cooling is
initiated, discontinue cooling and initiate appropriate protocol.
• CPR for more than 45 minutes • Comatose or vegetative state prior to cardiac arrest • Evidence of hypotension (MAP < 60) for more than 30 minutes after ROSC and prior to initiation of hypothermia • Terminal illness that preceded the arrest (life expectancy < 1 • Temperature <34°C • Inability to intubate patient • Appearance of the gravid abdomen • Active bleeding/known pre existing coagulopathy (Note: Thrombolytic therapy does not preclude the use of hypothermia) Medstar's pre-hospital protocol • Obtain core temperature with Temporal Scanner or rectal Hypothermia thermometer before initiation of protocol • Administer 100% FiO2 per ventilator or manual ventilation • ETCO2 target of 40mmhg, avoid hyperventilation
• Expose patient / cover lightly • Apply gel cooling packs to neck, axilla, groin • Keep patient sedated with Versed per protocol MedStar's protocol cont… • Paralyze patient to prevent shivering with Vecuronium • Administer cold normal saline (ideally 2°- 4° C [35.6 - 39.2° F]) boluses 30ml/kg to maximum of 2 liters over 30-60 minutes if patient can tolerate (No CHF) • Maintain core temperature between 32°- 34°C (89.6 - • Maintain MAP 90-100 (SBP 150). Administer vasopressors as indicated • Notify receiving hospital of induced hypothermia initiation Physiological changes with Hypothermia • Neurologic Effects Decreased metabolic rate 5-7 % for each 1 degree C Decreased Cerebral Blood Flow (vasoconstriction) Decreased Magnesium- associated with worse outcomes. May cause Cerebral and Coronary Vasoconstriction • Cardiovascular Effects Tachycardia then Bradycardia Increased B/P during Hypothermia / Increased SVR Hypotension during re-warming Intracellular Potassium Shifts- Hypokalemia can be significant. K+ levels decrease during cooling Replete carefully during rewarming, if < 2.7 Physiological changes with Hypothermia • Immune Effects Decreased Platelet Aggregation Increased Bleeding Time and ClottingLowers Number of Circulating WBCsSuppresses PMN release from Bone Marrow in response to infxnReduces production of Pro-Inflammatory CytokinesInfection Risk Increases AFTER 48 hrs of hypothermia • Renal Effects Decreases reabsorption of water in the asc limb of the loop of Henle.
Increased Urine Output "Cold Diuresis" during Induction May cause Hypotension and worsen cerebral perfusion. Physiological changes with Hypothermia Decreased gut motility-Ileus Increased LFTsRare- Mild Pancreatitis • Endocrine Effects Decreased Insulin secretion Insulin Drip Recommended 140-180mg/dlNeurotoxicity with Hyperglycemia Possible Increased Infection Risk Physiological changes with Hypothermia • Pulmonary Effects Risk of Ventilator associated pneumonia after 48 hrs CO2 Production decreased by 30% when at 33C decrease vent rate as low as 6 to 8 Complications of Hypothermia Ventilator Dependency Decreased WBC / BM Suppression Decreased Inflammatory cytokines Elevated Glucose Complications of Hypothermia • Miscellaneous Does NOT significantly increase metabolic acidosis or Lactate levels Will often cause mild HYPOTENSION, use Pressorsto maintain MAP > 80 for cerebral perfusion (90 – 100) Drug Metabolism slowed significantly (Propofol / Fentanyl / Verapamil / Propanolol) Complications of Hypothermia Increases O2 Consumption between 40 – 100% Shivering responses occur primarily between 30 – 35 C Sedation and anesthesia to halt shivering also increasePeripheral Blood Flow If you paralyze, you can't screen for seizures Buspirone (Buspar) 20mg PO q 8hrs / hold for SCr > 1.7Meperidine (Demerol) 25 – 50mg IV q 4 hrs prnUse Paralytics as second line Avoid Rebound Hyperthermia Potassium Levels Increase with Re-Warming (Initial Cold Diuresis & Hypokalemia with initial cooling (2.7)) Peripheral Vasodilation and Hypotension (Isotonic Fluid Replacement) Re-Warm NO FASTER than 0.25 – 0.33 C per Hour
• 16 year old male collapses playing basketball with V-fib arrest • ROSC, patient has GCS of 7 with • No history of cardiac issues, no family history, pt is on an unknown anti-biotic for sinusitis • Is this patient a candidate for Therapeutic Hypothermia treatment? • How would you initiate treatment? • How would you maintain hypothermia? • The patient has recurrent V Fib, how • What is the likely cause of arrest? • 65 year old male collapses at home, bystander CPR performed • ROSC after AED used by first responders • Brought to ED, responds only to central • History of CVA, on Coumadin Discussion Questions • Is this patient a candidate for Therapeutic • Why or Why not? • What is the likely cause of this patient's • 7 month pregnant female collapses at home found to be in V Tach • ROSC, in coma • No cardiac history, baby appears viable with good heart rate Discussion Questions • Is this patient a candidate for Therapeutic • Why or Why not? • Likely causes of this patient's collapse.

Source: https://www.nwmedstar.org/uploadedFiles/Services/Education_and_Outreach/Provider_Chats/Therapuetic%20Induced%20Hypothermia.pdf