Therapeutic hypothermia


Published on

Discussion of therapeutic hypothermia for cardiac arrest.

  • Be the first to comment

Therapeutic hypothermia

  1. 1. Therapeutic HypothermiaFrank W Meissner MD, FACP, FACC, FCCP, FASNC
  2. 2. The Hidden Obstacle to Reanimation CNS Reperfusion Injury Simply defined as ‘damage observed after resoration of blood flow to ischemic tissues’
  3. 3. Hypoxic Cerebral Insult6% Decrease in Cerebral Metabolism per1°C Decrease Core Body Temp => Anti-inflammatory EffectsResultant Suppression Of CNS ReperfusionInjury Decreased Free Radical Production Reduced Excitatory Neurotransmitters Suppression of Ca++ mediated cell death
  4. 4. Proof of Theory Studies
  5. 5. HACA* Study GroupWitnessed Cardiac Arrest (VF ^ VT) Age 18-75 yr Est time Reanimation attempt 5-15 min ROSC ≤ 60 mins275 of 3,551 Arrests Met Inclusion Criteria137 Randomized to Hypothermia Body Core Temperature 32-34° C X 24 hr Rewarmed over 8 hr * Hypothermia After Cardiac Arrest
  6. 6. Principle Results I Cumulative Survival in the Normothermia and Hypothermia GroupsThe Hypothermia after Cardiac Arrest Study Group, . N Engl J Med 2002;346:549-556
  7. 7. Principle Results IIThe Hypothermia after Cardiac Arrest Study Group, . N Engl J Med 2002;346:549-556
  8. 8. Current AHA (Y2005) GuidelineUnconscious adult patients with ROSC afterout-of-hospital arrest cooled to 32 - 34 °C(89.6 - 93.2° F) X 12-24 hr in V FibArrest(Class IIa)Similiar therapy may be beneficial for out-ofhospital or in-hospital non-VF arrest (ClassIIb)
  9. 9. Optimal Therapy
  10. 10. Surface Cooling I Conventional Surface Cooling (circulating cold water blankets or cold air-forced blankets) can take 4-8 hrs toreach 32-34° and temperature titration can be difficult CritiCool System uses 3-D CureWrap™ one piece garment with temperature controller resulting in high efficiency precisely controlled external cooling
  11. 11. Surface Cooling IIAdvantages Application in 2 minutes Portable no power requirements High Cooling Capacity Radioluminescent User friendly Suitable for induction and maintenance of cooling Low investment costs
  12. 12. Medivance Arctic Sun™Patented DesignArctic Sun andArcticGel™ Padsenables transfer ofup to five timesmore thermalenergy thanconventionalmethods such aswater blankets,wraps or ice packs.System’s precisionenables slowrewarming thoughtto be critical fortherapeutic benefit. The Arctic Sun hasreceived 510(k) FDAclearance in theU.S.
  13. 13. Blanketrol™ III
  14. 14. Invasive Cooling Methods I 30ml/kg Lacated Ringers Solution @ 4° C infused via femoral catheter over 30 mins => T 35.5 to 33.8° C Rapid & predictable + volume infusion blunts hypothermia induced diuresis Maintenance therapy cooling blanketsBernard, S. et al. Induced hypothermia using large volume, ice-cold intravenous fluid in comatose survivors of out-of-hospital cardiac arrest: A preliminary report. Resuscitation 2003;56:9-13)
  15. 15. Invasive Cooling Methods IIShivering bluntsexternal coolingefforts unlessmoderated byPropofol orBenzo’s Zoll (Formerly Alsius) Thermogard XP System
  16. 16. Thermal Regulatory Performance Cincinnati Medeco Icy Catheter Arctic Sun Subzero Conventional Caircooler Blanketrol III External H20 Cooling IV Heat External Gel- External Air Cold Saline, Ice, Circulating Circulating Pads Method Exchange coated Pads bags, Etc. Pads Cooling Rate (°C) 1.46 1.04 1.33 0.18 0.32 % of time Temp out of range (>0.2 °C from 3.2 44.2 50.5 74.1 69.8 Target Temp) Hoedemaekers CW, et al. Comparison of different cooling methods to induce and maintain normo- and hypothermia in ICU patients: a prospective intervention study. Critical Care 2007; 11:R91.
  17. 17. Invasive Cooling III Zoll Catheter Systems
  18. 18. Invasive Cooling IVZoll Catheter Systems
  19. 19. Practical ApproachInduction Phase (within 4 hr of arrest) Cold IV Saline NG Iced Lavage Cold Packs in Groin & AxillaMaintenance Phase (12 to 24 hr) IV Cooling Catheter External Cooling Patches or Arctic Sun SystemRewarming Phase (Precise Temp Control VITAL) 0.25 - 0.5 ° C/hr
  20. 20. Financial Analysis Avg Avg Direct Avg Direct Revenue Margin Per Cost Per Pt Per Pt PtDischarged $57,783 $37,099 $20,684 AliveExpired in $12,014 $8,686 $3,329 Hospital Take Heart America Program St Cloud Minn - Dec 05- Nov 07
  21. 21. Financial AnalysisOn average, each SCA patient deliveredalive to ED generated $27,900 ofrevenue & $9,400 of direct marginregardless of outcome in the hospital
  22. 22. Financial AnalysisSt Cloud saw a 131% increase in arrestsurvival rate compared to previous year=> $1,088,000 additional hospitalrevenue with direct margin of $366,000over 19 month period of the study
  23. 23. Knowledge TransitionHACA Theory Into Practice Europe & USA 30-40%Implementation of therapeutic hypothermiaguidelines for post-cardiac arrest syndrome at aglacial pace: Seeking guidance from theknowledge translation literatureResuscitation - Volume 77, Issue 3,Pages 286-292 (June 2008)
  24. 24. Barrier’s To Implementation500% variation in post arrest survivalTherapeutic Nihilism & FatalismStove-piped ProcessesInability To Effectively TeamLack of Physician ChampionInstitutional Financial Concerns
  25. 25. Level I Cardiac Arrest Center Minimum of 40 reanimated patient’s annually Aligned with STEMI Primary PCI Treatment of re-arrest EP assessment and/or ICD assessment and implantation
  26. 26. Roadmap