Table 1 Demographic and Intraoperative Characteristics

Age (years)

56.15 ± 9.57

56.58 ± 9.53

0.832^△

Gender (Male/Female)

15/25

19/21

0.366^&

BMI (kg/m²)

24.86 ± 2.33

25.21 ± 2.50

0.445^△

Smoking history (no/current)

34/6

35/5

0.745^&

ASA rating (II/III)

33/7

28/12

0.189^&

Comorbidities (n)

 Hypertension

 Coronary heart disease

 Diabetes

15(37.5%)

3(7.5%)

2(5%)

13(32.5%)

2(5%)

5(12.5%)

0.639^&

0.644^&

0.235^&

Preoperative blood gas

 pH

 PaO₂ (mmHg)

 PaCO₂ (mmHg)

 Hb(g/L)

7.40 ± 0.12

88.08 ± 12.40

41.47 ± 3.07

137.13 ± 14.47

7.40 ± 0.02

84.25 ± 15.06

41.39 ± 2.90

137.13 ± 15.96

0.737^△

0.990^△

0.979^△

0.719^△

Preoperative pulmonary function

 Preoperative FEV₁

 Preoperative FVC

 Preoperative FEV₁/FVC

2.66 ± 0.46

3.29 ± 0.54

80.53 ± 3.52

2.78 ± 0.46

3.44 ± 0.57

80.72 ± 3.31

0.251^△

0.246^△

0.799^△

Preoperative heart function

 LVEF (%)

64.75 ± 4.11

65.40 ± 4.74

0.385^△

Type of surgery Lobectomy

 Lobectomy

 Wedge resection

 Segmentectomy

28(70.0%)

8(20.0%)

4(10.0%)

30(75%)

8(20.0%)

2(5.0%)

0.692^&

Operative site

 Left/right

14/26

13/27

0.813^&

Operation time (min)

140.75 ± 47.21

153.50 ± 53.32

0.261^△

Anesthesia time (min)

182.88 ± 46.20

196.38 ± 52.78

0.227^△

One lung ventilation time (min)

120.38 ± 45.64

133.25 ± 50.17

0.234^△

Intraoperative fluid load (L)

1.32 ± 0.20

1.34 ± 0.16

0.642^△

Intraoperative urine (L)

0.35 ± 0.03

0.35 ± 0.02

0.973^△