Table 4

Randomised clinical trials

Study (no. of patients)	Year	Initial cardiac rhythm	Cooling method + target temperature	T_targ	Duration of cooling	Patients	Survival to hospital discharge	Favourable neurological outcome	Jadad	Comments
Hachimi-Idrissi32 (n=30)	2001	Asystole or PEA	Cooling helmet 34°C	3 h post-ROSC	4 h	16 MTH 14 normothermia	MTH: 2/16 (13%) Normothermia: 0/14	Same as survival rate	3	Results NS (p=0.49)
Bernard2 (n=77)	2002	VF or pulseless VT	Ice packs 33°C	2 h post-ROSC	12 h	43 MTH 34 normothermia	MTH: 21/43 (49%) Normothermia: 9/34 (26%)	Same as survival rate. OR for favourable neuro. recovery 5.25 (95% CI 1.47 to 18.79)	1	Results significant (p=0.046)
HACA3 (n=275)	2002	VF or pulseless VT	Cooling mattress/ice packs 32–34°C	6 h after initiating cooling	24 h	136 MTH 137 normothermia		MTH: 75/1236 (55%) NT: 54/137 (39%)	3	Trend towards high infection rate in hypothermia group but benefit deemed to outweigh risk
Laurent33 (n=61)	2005	VF or asystole	Cooling of the substitution fluid on haemofiltraiton		24 h	20 Haemofiltration 22 Haemofiltration + hypothermia	OR for survival 4.4 (95% CI 1.1 to 16.6)		2	Results from haemofiltration alone were similar to haemofiltration with MTH. Haemofiltration is not practical for use within ED
Kim34 (n=125)	2007	All rhythms after non-traumatic OHCA	Infusion of up to 2 litres of 4°C saline prehospital	Variable	Variable	63 cooling 62 normothermia	NS		3	Significantly lower ED arrival temperature (34.7 vs 35.7°C) in group treated with cold intravenous fluid. Trend towards worse survival in non-VF patients treated with hypothermia. Only 78% randomised to cooling received treatment

ED, Emergency Department; MTH, mild therpautic hypothermia; NS, non-significant; OHCA, out-of-hospital cardiac arrest; PEA, pulseless electrical activity; ROSC, return of spontaneous circulation; T_targ, time to target temperature; VF, ventricular fibrillation; VT, ventricular tachycardia.