Study | Year | Initial cardiac rhythm | Cooling method + target temperature | Ttarg (min) | Duration of cooling | Outcomes |
Bernard6 (n=22) | 1997 | Any | Ice packs 33°C | 74 | 12 h | No significant side effects. Increased survival and better neurological outcome compared with historical controls |
Yanagawa7 (n=13) | 1998 | Any | Cooling blanket 33–34°C | 414 | 48 h | Cooling associated with increased rates of pneumonia. Higher survival and recovery rates in hypothermia group |
Zeiner25 (n=27) | 2000 | Any | Cold air | 276 | >24 h | No major complications in first 24 h. Mild resuscitative hypothermia shown to be safe and feasible |
Felberg26 (n=9) | 2001 | Any | Cooling blanket | 378 | 24 h | No major complications. Cooling methods found to be slow and imprecise. Favourable neurological outcome demonstrated |
Bernard27 (n=22) | 2003 | Any | Cold fluids (30 ml/kg 4°C Ringer's), ice | ASAP | Rapid drop in core body temperature from 35.5 to 33.8°C, improved BP and renal function. No cases of pulmonary oedema | |
Kim28 (n=17) | 2005 | Any | Cold fluids (2 litres of 4°C saline) | ASAP | 24 h | Fluid infusion did not alter ejection fraction, central venous pressure or pulmonary pressures |
Busch29 (n=27) | 2006 | Any | Sports ice packs and water-soaked towels placed prehospital | 450 | 12–24 h | Cooling rates found to be slow. Higher in-hospital survival rates in cooled patients |
Merchant30 (n=32) | 2006 | Any | Cooling blanket | 360 | 12–24 h | Majority of cases showed unintentional overcooling to <32°C |
Kliegel31 (n=20) | 2007 | Any | Cold fluids (4°C saline 30 ml/kg/h) | 60 | 24 h | Majority reached <34°C in <60 min |
ASAP, as soon as possible; BP, blood pressure; Ttarg, time to target temperature.