Table 1 Baseline characteristics of participants. (N = 647)

N

647

410

237

Age, (year)

61.06 ± 8.16

60.34 ± 8.30

62.31 ± 7.79

Gender, n (%)

Male

501 (77.43%)

321 (78.29%)

180 (75.95%)

Female

146 (22.57%)

89 (21.71%)

57 (24.05%)

Comorbidities, n (%)

Hypertension

102 (15.77%)

64 (15.61%)

38 (16.03%)

Diabetes

47 (7.26%)

27 (6.59%)

20 (8.44%)

Heart disease

67 (10.36%)

44 (10.73%)

23 (9.70%)

Central nervous system

14 (2.16%)

9 (2.20%)

5 (2.11%)

Lung disease

150 (23.18%)

87 (21.22%)

63 (26.58%)

Laboratory examination

Hb, (g/dL)

13.09 ± 1.51

13.95 ± 0.97

11.59 ± 1.04

WBC, (×10^9/L)

7.13 ± 2.14

7.31 ± 1.95

6.82 ± 2.40

Na⁺, (mmol/L)

139.18 ± 3.14

139.27 ± 3.23

139.02 ± 2.97

 K⁺, (mmol/L)

4.00 ± 0.37

4.01 ± 0.35

3.99 ± 0.40

SCr, (mol/L)

90.51 ± 23.12

90.56 ± 19.69

90.41 ± 28.14

PT, (s)

11.02 ± 0.87

10.99 ± 0.85

11.06 ± 0.91

APTT, (s)

27.54 ± 4.86

27.25 ± 4.70

28.04 ± 5.08

Preoperative chemotherapy

142 (21.95%)

43 (10.49%)

99 (41.77%)

ASA ≥ 3

53 (8.19%)

28 (6.83%)

25 (10.55%)

Anesthesia

General + epidural

462 (71.41%)

297 (72.44%)

165 (69.62%)

General

185 (28.59%)

113 (27.56%)

72 (30.38%)

Operation form

Minimally invasive

300 (46.37%)

189 (46.10%)

111 (46.84%)

Open

347 (53.63%)

221 (53.90%)

126 (53.16%)

Operation time, (min)

239.13 ± 56.72

239.29 ± 61.03

238.87 ± 48.48

Blood loss, (ml)

198.61 ± 157.74

198.07 ± 168.76

199.54 ± 136.92

Fluid infusion, (ml)

2556.26 ± 604.97

2572.93 ± 608.48

2527.43 ± 599.05

Blood transfusion

127 (19.63%)

58 (14.15%)

69 (29.11%)

Postoperative admission to ICU

42 (6.49%)

23 (5.61%)

19 (8.02%)

Postoperative complications

Respiratory failure

24 (3.71%)

15 (3.66%)

9 (3.80%)

Lung infection

212 (32.77%)

129 (31.46%)

83 (35.02%)

Anastomotic fistula

42 (6.49%)

28 (6.83%)

14 (5.91%)

Cardiovascular complication

33 (5.10%)

20 (4.88%)

13 (5.49%)

LOS, (days)

26.31 ± 13.19

25.40 ± 11.44

27.89 ± 15.66