Table 2.

Univariate analysis of preoperative clinical risk factors related to pulmonary complications of hepatectomy

Variable	n	Pearson coefficient	P value 1
Age (years old)		0.087	0.000
≥ 65	147
< 65	1486
Medical diseases requiring drug treatment		0.200	< 0.001
Yes	248
No	1385
Child-pugh grade		0.093	< 0.001
A	1463
B, C	170
Number of segments resected		0.124	< 0.001
≤ 2 segments resected	1046
≥ 3 segments resected	587
Blood transfusion		0.182	0.000
Yes	689
No	944
Blood loss (mL)		0.103	< 0.001
≥ 800	204
< 800	1429
Operation duration (min)		0.169	0.000
≥ 180	922
< 180	711
Adjacent organ invasion		0.066	0.007
Yes	18
No	1615
Preoperative hospital stay (days)		0.098	0.000
≤ 7	1142
> 7	491

¹Pearson’s correlation analysis.