Comparison 1. Intervention versus control.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Mortality	8		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
1.1 Low CVP versus control	3	177	Risk Ratio (M‐H, Fixed, 95% CI)	0.36 [0.02, 8.43]
1.2 Autologous blood donation versus control	1	79	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
1.3 Haemodilution versus control	2	150	Risk Ratio (M‐H, Fixed, 95% CI)	0.35 [0.04, 3.32]
1.4 Haemodilution with controlled hypotension versus control	1	20	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
1.5 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1	12	Risk Ratio (M‐H, Fixed, 95% CI)	3.0 [0.15, 61.74]
1.6 Hypoventilation versus control	1	79	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
2 Serious adverse events	5		Rate Ratio (Fixed, 95% CI)	0.97 [0.57, 1.65]
2.1 Autologous blood donation versus control	1		Rate Ratio (Fixed, 95% CI)	0.49 [0.04, 5.32]
2.2 Haemodilution versus control	2		Rate Ratio (Fixed, 95% CI)	1.01 [0.57, 1.80]
2.3 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1		Rate Ratio (Fixed, 95% CI)	0.50 [0.05, 5.48]
2.4 Hypoventilation versus control	1		Rate Ratio (Fixed, 95% CI)	1.95 [0.18, 21.35]
3 Adverse events (severity unknown)	4		Rate Ratio (Fixed, 95% CI)	1.12 [0.68, 1.85]
3.1 Low CVP versus control	2		Rate Ratio (Fixed, 95% CI)	0.76 [0.28, 2.03]
3.2 Haemodilution versus control	1		Rate Ratio (Fixed, 95% CI)	1.38 [0.56, 3.39]
3.3 Hypoventilation versus control	1		Rate Ratio (Fixed, 95% CI)	1.22 [0.57, 2.62]
4 Number requiring allogeneic blood transfusion	8		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.1 Low CVP versus control	3	177	Risk Ratio (M‐H, Fixed, 95% CI)	0.66 [0.42, 1.03]
4.2 Autologous blood donation versus control	1	79	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
4.3 Haemodilution versus control	3	233	Risk Ratio (M‐H, Fixed, 95% CI)	0.41 [0.25, 0.66]
4.4 Haemodilution with controlled hypotension versus control	1	20	Risk Ratio (M‐H, Fixed, 95% CI)	0.05 [0.00, 0.72]
4.5 Hypoventilation versus control	1	79	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.17, 3.06]
5 Red cell transfusion	7		Std. Mean Difference (IV, Fixed, 95% CI)	Subtotals only
5.1 Low CVP versus control	2	135	Std. Mean Difference (IV, Fixed, 95% CI)	‐0.31 [‐0.65, 0.03]
5.2 Haemodilution versus control	3	180	Std. Mean Difference (IV, Fixed, 95% CI)	‐0.33 [‐0.63, ‐0.03]
5.3 Haemodilution with controlled hypotension versus control	1	20	Std. Mean Difference (IV, Fixed, 95% CI)	‐3.63 [‐5.16, ‐2.10]
5.4 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1	12	Std. Mean Difference (IV, Fixed, 95% CI)	0.23 [‐0.91, 1.36]
5.5 Hypoventilation versus control	1	80	Std. Mean Difference (IV, Fixed, 95% CI)	‐0.12 [‐0.55, 0.32]
6 Fresh frozen plasma			Other data	No numeric data
6.1 Low central venous pressure versus control			Other data	No numeric data
7 Operative blood loss (ml)	8		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
7.1 Low central venous pressure versus control	3	175	Mean Difference (IV, Fixed, 95% CI)	‐419.35 [‐575.06, ‐263.63]
7.2 Autologous blood donation versus control	1	79	Mean Difference (IV, Fixed, 95% CI)	‐37.0 [‐100.51, 26.51]
7.3 Haemodilution versus control	3	128	Mean Difference (IV, Fixed, 95% CI)	‐17.95 [‐67.89, 32.00]
7.4 Haemodilution with controlled hypotension versus control	1	20	Mean Difference (IV, Fixed, 95% CI)	‐245.00 [‐357.80, ‐136.20]
7.5 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1	12	Mean Difference (IV, Fixed, 95% CI)	370.0 [‐1103.59, 1843.59]
8 Operating time (minutes)	5		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
8.1 Low CVP versus control	2	90	Mean Difference (IV, Fixed, 95% CI)	‐24.69 [‐44.28, ‐5.09]
8.2 Haemodilution versus control	2	208	Mean Difference (IV, Fixed, 95% CI)	‐28.86 [‐57.37, ‐0.35]
8.3 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1	12	Mean Difference (IV, Fixed, 95% CI)	23.0 [‐83.60, 129.60]
9 Hospital stay (days)	4		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
9.1 Low CVP versus control	2	135	Mean Difference (IV, Fixed, 95% CI)	‐4.53 [‐7.38, ‐1.68]
9.2 Haemodilution versus control	1	130	Mean Difference (IV, Fixed, 95% CI)	0.0 [‐2.66, 2.66]
9.3 Haemodilution with bovine haemoglobin (HBOC‐201) versus haemodilution with hydroxy ethyl starch (HES)	1	12	Mean Difference (IV, Fixed, 95% CI)	2.30 [‐7.52, 12.12]