Table 1 Patient characteristics before and after propensity score matching

Age (year)

69.0 (58.0–76.0)

73.0 (65.0–81.0)

 < 0.001

0.388

71.0 (62.0–78.0)

72.0 (64.0–78.0)

0.392

0.085

Male

252 (64.1%)

87 (51.5%)

0.007

0.258

70 (49.6%)

73 (51.8%)

0.812

0.043

BMI (kg/m2)

22.1 (19.9–24.6)

22.0 (19.4–24.7)

0.592

0.041

22.2 (19.7–24.6)

22.0 (19.4–24.7)

0.894

0.036

ASA-PS

 < 0.001

0.459

0.742

0.133

 Class 1

23 (5.9%)

 Class 2

291 (74.0%)

7 (4.1%)

4 (2.8%)

7 (5.0%)

 Class 3

78 (19.8%)

94 (55.6%)

88 (62.4%)

84 (59.6%)

 Class 4

1 (0.3%)

65 (38.5%)

48 (34.0%)

48 (34.0%)

Comorbidities

3 (1.8%)

1 (0.7%)

2 (1.4%)

 Hypertension

136 (34.6%)

  CAD

28 (7.1%)

73 (43.2%)

0.066

0.177

56 (39.7%)

57 (40.4%)

1

0.014

  CVD

33 (8.4%)

22 (13.0%)

0.037

0.197

16 (11.3%)

14 (9.9%)

0.847

0.046

  Diabetes mellitus

55 (14.0%)

13 (7.7%)

0.911

0.026

10 (7.1%)

10 (7.1%)

1

 < 0.001

Medication history

27 (16.0%)

0.631

0.056

24 (17.0%)

23 (16.3%)

1

0.019

 ACEI or ARB

91 (23.2%)

Operative profiles

45 (26.6%)

0.439

0.08

36 (25.5%)

36 (25.5%)

1

 < 0.001

Type of surgery

 General surgery

97 (24.7%)

57 (33.7%)

 < 0.001

0.732

45 (31.9%)

49 (34.8%)

0.957

0.171

 Gynecology Surgery

16 (4.1%)

6 (3.6%)

5 (3.5%)

6 (4.3%)

 Hepatobiliary Surgery

24 (6.1%)

3 (1.8%)

5 (3.5%)

3 (2.1%)

 Neurosurgery

37 (9.4%)

15 (8.9%)

17 (12.1%)

15 (10.6%)

 Orthopedic surgery

25 (6.4%)

38 (22.5%)

23 (16.3%)

23 (16.3%)

 Other surgery

84 (21.4%)

8 (4.7%)

12 (8.5%)

8 (5.7%)

 Thoracic surgery

85 (21.6%)

33 (19.5%)

24 (17.0%)

28 (19.9%)

 Urological surgery

25 (6.4%)

9 (5.3%)

10 (7.1%)

9 (6.4%)

Combined with epidural anesthesia

141 (35.9%)

43 (25.4%)

0.02

0.228

34 (24.1%)

42 (29.8%)

0.347

0.128

Scheduled surgery

375 (95.4%)

151 (89.3%)

0.012

0.23

128 (90.8%)

131 (92.9%)

0.663

0.078