Table 2.

Perioperative characteristics.

Variables	Before PS Matching			After PS Matching
	OLR (n = 160)	LLR (n = 96)	p-Value	OLR (n = 91)	LLR (n = 91)	p-Value
ASA classification			0.949			0.648
1	10 (6.3%)	3 (3.1%)		3 (3.3%)	2 (2.2%)
2	134 (83.8%)	86 (89.6%)		78 (85.7%)	82 (90.1%)
3	16 (10.0%)	7 (7.3%)		10 (11.0%)	7 (7.7%)
Previous abdominal operation	42 (26.3%)	18 (18.8%)	0.223	23 (25.3%)	16 (17.6%)	0.278
Extent of resection (major)	79 (49.4%)	46 (48.4%)	0.898	40 (44.0%)	44 (48.9%)	0.552
Operation time (min)	222 (71–599)	239 (43–590)	0.345	204 (71–408)	240 (43–590)	0.040
Blood loss during operation (mL)	300 (30–3000)	250 (30–2500)	0.750	200 (50–1500)	250 (50–2500)	0.172
RBC transfusion during operation	10 (6.3%)	4 (4.2%)	0.579	1 (1.1%)	4 (4.4%)	0.368
Tumor size (cm)	3.9 (0.3–17.0)	2.6 (0.9–14.0)	<0.001	2.9 (0.3–13.2)	2.6 (0.9–14.0)	0.445
Tumor size > 10 cm	12 (7.5%)	4 (4.2%)	0.425	3 (3.3%)	4 (4.4%)	0.700
Tumor grade 3 or 4	21 (13.3%)	5 (5.2%)	0.053	11 (12.4%)	4 (4.4%)	0.063
Tumor necrosis	67 (43.5%)	35 (38.0%)	0.425	33 (37.9%)	34 (39.1%)	0.876
Complete encapsulation	121 (77.6%)	68 (70.8%)	0.189	63 (72.4%)	64 (70.3%)	0.843
Microvascular invasion	110 (68.8%)	58 (60.4%)	0.178	51 (56.0%)	58 (63.7%)	0.364
Portal vein tumor thrombosis	5 (3.1%)	7 (7.3%)	0.139	0 (0%)	7 (7.7%)	0.014
Intrahepatic metastasis	6 (3.8%)	2 (2.1%)	0.714	3 (3.3%)	2 (2.2%)	0.650
Cirrhosis	50 (31.3%)	46 (47.9%)	0.011	40 (44.0%)	43 (47.3%)	0.766
Free resection margin (mm)	10 (2–55)	10 (2–65)	0.428	10 (2–55)	10 (2–65)	0.865
Hospitalization (day)	10 (5–177)	7 (4–41)	<0.001	9 (5–177)	7 (4–41)	<0.001

PS, propensity score; OLR, open liver resection; LLR, laparoscopic liver resection; ASA, American Standards Association; RBC, red blood cell.