Table 4. The multivariate analysis results.

Risk factors	No. of study	Heterogeneity		ES (Effect size, 95% CI)	P	P of Egger
		I2 (%)	P
Age	4	12.8	0.329	0.01 (−0.02, 0.04)	0.477	0.188
BMI	2	0	0.462	−0.35 (−0.65, −0.05)	0.021	<0.001
Male	2	80	0.025	−0.35 (−1.53, 0.83)	0.565	<0.001
eGFR, mL/min	3	80.1	0.007	0.00 (−0.02, 0.02)	0.999	0.153
Pulmonary hypertension before surgery	2	76.1	0.410	0.24 (−1.05, 1.54)	0.711	<0.001
Diabetes	2	0	0.708	0.05 (−0.71, 0.80)	0.870	<0.001
Pulmonary hypertension	2	46.1	0.173	0.38 (−1.15, 1.91)	0.623	<0.001
Cystic fibrosis	2	0	0.975	0.77 (0.24, 1.30)	0.040	<0.001
Double lung transplantation	4	0	0.446	1.09 (0.59, 1.58)	<0.001	0.722
Cardiopulmonary bypass	2	0	0.564	0.00 (0.00, 0.01)	0.018	<0.001
Intra-op ECMO	4	0	0.876	0.09 (−0.43, 0.61)	0.742	0.526
Duration of mechanical ventilation	3	96.5	<0.001	0.17 (−2.79, 3.13)	0.909	0.638
Post-op ECMO	2	14.9	0.278	1.55 (0.15, 2.96)	0.030	<0.001
Mechanical ventilation >3 d	2	82.3	0.018	0.77 (−1.08, 2.62)	0.416	<0.001