Table 1.

Results of subgroup analysis

Subgroup		Pooled survival (%)	95% CI (%)
Geographical region (p < 0.001)	Asia	19.5	13.0 to 26.8
	Europe and North America	57.8	44.8 to 70.3
Presence of CPR (p = 0.55)	CPR	Survival = 24.4% (21 of 86)
	No CPR	Survival = 27.3% (54 of 144)
LVEF (p = 0.09)	< 20%	62.0	51.6 to 72.1
	20 to 35%	42.3	6.70 to 82.8
	> 35%	32.1	8.70 to 60.7
Serum lactate (p = 0.20)	< 5 mmol/l	50.5	29.8 to 71.2
	> 5 mmol/l	32.2	16.2 to 50.7

CI confidence interval; VA Venoarterial; VV venovenous; CPR cardiopulmonary resuscitation; LVEF left ventricular ejection fraction