Al-Harthi et al,9 1986, Saudi Arabia | 16 heatstroke patients (Tre>40°C, dry skin, CNS symptoms). Randomised to BCU or CM (see text) | Prospective randomised controlled trial | Cooling time to Tre<38.5°C, mortality | Mean cooling time 62 min (35–120) (BCU) and 64 min (35–120) (CM); no difference between groups. No deaths in patients followed up | Randomisation technique not defined. Small numbers. Not blinded. No exclusion criteria given. Outcomes not clearly defined. 2 patients lost to follow up. Comparison between 2 types of evaporative cooling |
Channa et al,11 1990, Saudi Arabia | 20 classical heatstroke patients, Tre>41.9°C. Either given dantrolene 2–4 mg/kg or not | Prospective randomised controlled trial | Cooling time to Tre<39.0°C, neurological outcome, mortality | Mean (SD) cooling time significantly lower in treatment group: 49.7 (4.4) v 69.2 (4.8) min (p<0.01). No difference in outcome or mortality (all patients survived) | Small numbers not justified by power calculation. Randomisation not defined. Not blinded. Inclusion and exclusion criteria not clear. Possible bias from different cooling methods and different doses of dantrolene. The conclusion does not reflect the results |
Bouchama et al,12 1991, Saudi Arabia | 52 classical heatstroke patients with Tre>40.1°C. Given dantrolene 2 mg/kg or placebo | Prospective randomised controlled trial | Cooling time to Tre<39.4°C, organ dysfunction, length of hospital stay, mortality | No significant difference between study group and control group in cooling time (67.9 (12.4) v 69.0 (10.5) min), organ dysfunction, length of hospital stay or mortality | Better study design. Powered to detect difference in cooling time of 30 min. Computer randomisation in blocks of 10. Treatment blinded to patients and clinicians. No mention of outcomes being blinded. Classical heatstroke patients |
Armstrong et al,10 1996, USA | 21 exertional heatstroke patients, cooled either by iced water immersion or wet towels | Non-randomised comparative trial | Cooling rates to unspecified target | Cooling rate 0.20°C/min for iced water, 0.11°C/min for wet towels | Non-randomised, large potential for bias. No outcome target given. Flawed comparison |