BACKGROUND: Mild therapeutic hypothermia (HT) has been implemented in the management of post cardiac arrest (CA) syndrome after the publication of clinical trials comparing HT with common practice (ie, usually hyperthermia). Current evidence on the comparison between therapeutic HT and controlled normothermia (NT) in CA survivors, however, remains insufficient. METHODS: Eight female swine (sus scrofa domestica; body weight 45 kg) were randomly assigned to receive either mild therapeutic HT or controlled NT, with four animals per group. Veno-arterial extracorporeal membrane oxygenation (ECMO) was established and at minimal ECMO flow (0.5 L/min) ventricular fibrillation was induced by rapid ventricular pacing. After 20 min of CA, circulation was restored by increasing the ECMO flow to 4.5 L/min; 90 min of reperfusion followed. Target core temperatures (HT: 33°C; NT: 36.8°C) were maintained using the heat exchanger on the oxygenator. Invasive blood pressure was measured in the aortic arch, and cerebral oxygenation was assessed using near-infrared spectroscopy. After 60 min of reperfusion, up to three defibrillation attempts were performed. After 90 min of reperfusion, blood samples were drawn for the measurement of troponin I (TnI), myoglobin (MGB), creatine-phosphokinase (CPK), alanin-aminotransferase (ALT), neuron-specific enolase (NSE) and cystatin C (CysC) levels. Reactive oxygen metabolite (ROM) levels and biological antioxidant potential (BAP) were also measured. RESULTS: Significantly higher blood pressure and cerebral oxygenation values were observed in the HT group (P<0.05). Sinus rhythm was restored in all of the HT animals and in one from the NT group. The levels of TnI, MGB, CPK, ALT, and ROM were significantly lower in the HT group (P<0.05); levels of NSE, CysC, and BAP were comparable in both groups. CONCLUSIONS: Our results from animal model of cardiac arrest indicate that HT may be superior to NT for the maintenance of blood pressure, cerebral oxygenation, organ protection and oxidative stress suppression following CA.

Cardiovascular Center Na Homolce Hospital Prague 15030 Czech Republic

Zobrazit více v PubMed

HACA-Study-Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med. 2002;346:549–556. PubMed

Bernard SA, Gray TW, Buist MD, Jones BM, Silvester W, Gutteridge G, Smith K. Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med. 2002;346:557–563. doi: 10.1056/NEJMoa003289. PubMed DOI

Peberdy MA, Callaway CW, Neumar RW, Geocadin RG, Zimmerman JL, Donnino M, Gabrielli A, Silvers SM, Zaritsky AL, Merchant R. Part 9: post-cardiac arrest care: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010;122:S768–S786. doi: 10.1161/CIRCULATIONAHA.110.971002. PubMed DOI

Deakin CD, Nolan JP, Soar J, Sunde K, Koster RW, Smith GB, Perkins GD. European Resuscitation Council Guidelines for Resuscitation 2010 Section 4. Adult advanced life support. Resuscitation. 2010;81:1305–1352. doi: 10.1016/j.resuscitation.2010.08.017. PubMed DOI

Holzer M, Bernard SA, Hachimi-Idrissi S, Roine RO, Sterz F, Mullner M. Hypothermia for neuroprotection after cardiac arrest: systematic review and individual patient data meta-analysis. Crit Care Med. 2005;33:414–418. doi: 10.1097/01.CCM.0000153410.87750.53. PubMed DOI

Arrich J, Holzer M, Herkner H, Mullner M. Hypothermia for neuroprotection in adults after cardiopulmonary resuscitation. Cochrane Database Syst Rev. 2009. p. CD004128. PubMed

Nielsen N, Friberg H. Insights from the evidence evaluation process–do we have the answers for therapeutic hypothermia? Resuscitation. 2011;82:501–502. doi: 10.1016/j.resuscitation.2011.02.041. PubMed DOI

Nielsen N, Friberg H, Gluud C, Herlitz J, Wetterslev J. Hypothermia after cardiac arrest should be further evaluated–a systematic review of randomised trials with meta-analysis and trial sequential analysis. Int J Cardiol. 2011;151:333–341. doi: 10.1016/j.ijcard.2010.06.008. PubMed DOI

Badjatia N. Hyperthermia and fever control in brain injury. Crit Care Med. 2009;37:S250–S257. doi: 10.1097/CCM.0b013e3181aa5e8d. PubMed DOI

Zeiner A, Holzer M, Sterz F, Schorkhuber W, Eisenburger P, Havel C, Kliegel A, Laggner AN. Hyperthermia after cardiac arrest is associated with an unfavorable neurologic outcome. Arch Intern Med. 2001;161:2007–2012. doi: 10.1001/archinte.161.16.2007. PubMed DOI

Takasu A, Saitoh D, Kaneko N, Sakamoto T, Okada Y. Hyperthermia: is it an ominous sign after cardiac arrest? Resuscitation. 2001;49:273–277. doi: 10.1016/S0300-9572(00)00360-9. PubMed DOI

Nielsen N, Wetterslev J, al-Subaie N, Andersson B, Bro-Jeppesen J, Bishop G, Brunetti I, Cranshaw J, Cronberg T, Edqvist K. Target Temperature Management after out-of-hospital cardiac arrest–a randomized, parallel-group, assessor-blinded clinical trial–rationale and design. Am Heart J. 2012;163:541–548. doi: 10.1016/j.ahj.2012.01.013. PubMed DOI

Horburger D, Testori C, Sterz F, Herkner H, Krizanac D, Uray T, Schober A, Stockl M, Stratil P, Weiser C. Mild therapeutic hypothermia improves outcomes compared with normothermia in cardiac-arrest patients-a retrospective chart review. Crit Care Med. 2012. PubMed

Jia X, Koenig MA, Venkatraman A, Thakor NV, Geocadin RG. Post-cardiac arrest temperature manipulation alters early EEG bursting in rats. Resuscitation. 2008;78:367–373. doi: 10.1016/j.resuscitation.2008.04.011. PubMed DOI PMC

Kruger A, Ostadal P, Vondrakova D, Janotka M, Herget J. Nitrotyrosine and nitrate/nitrite levels in cardiac arrest survivors treated with endovascular hypothermia. Physiol Res. 2012;61:425–430. PubMed

Ten years of our translational research in the field of veno-arterial extracorporeal membrane oxygenation

Inducibility of ventricular fibrillation during mild therapeutic hypothermia: electrophysiological study in a swine model