Table 1 Comparison of risk factors between abdominal distension and non-distended groups (n = 1317)

Women (M/W), n(%)

107(58.79)

563(49.60)

Age (yr.), M ( Q₁, Q₃)

55.5(48,63.25)

57(50,66)

Age (yr.), n(%)

18∼20

5(2.75)

9(0.79)

21∼30

5(2.75)

21(1.85)

31∼40

11(6.04)

76(6.70)

41∼50

41(22.53)

185(16.30)

51∼60

66(36.26)

359(31.63)

61∼70

44(24.18)

350(30.84)

71∼80

10(5.49)

135(11.89)

BMI (kg/m²), M ( Q₁, Q₃)

23.23(21.31,24.98)

23.23(21.31,25.25)

TNM stage, n(%)

I

118(64.84)

794(69.95)

II

25(13.74)

176(15.51)

III

27(14.83)

101(8.90)

IV

12(6.59)

64(5.64)

Operation duration (h), (\(\overline x \pm s\))

1:50 ± 1:02

1:41 ± 0:55

Sedation and the amount of curarization time (h), (\(\overline x \pm s\))

4:17 ± 1:09

4:15 ± 1:09

Postoperative extubation time (hours), (\(\overline x \pm s\))

6:11 ± 3:15

6:04 ± 3:03

Surgical approach, n(%)

Open thoracotomy

134(73.63)

491(43.26)

VATS

48(26.37)

644(56.74)

Type of surgical resection, n(%)

Wedge resection

16(8.79)

139(12.25)

Segmentectomy

60(32.97)

269(23.70)

Lobectomy

82(45.05)

642(56.56)

Pneumonectomy

3(1.65)

10(0.88)

Others

21(11.54)

75(6.61)

Basic diseases history, n(%)

no

52(28.57)

282(24.85)

yes

130(71.43)

853(75.15)

Neoadjuvant Chemotherapy, n(%)

no

150(82.42)

1039(91.54)

yes

32(17.58)

96(8.46)

Postoperative pain level, n(%)

mild

171(93.96)

1084(95.51)

moderate

11(6.04)

51(4.49)

Postoperative opioid analgesic use, n(%)

no

92(50.55)

508(44.76)

yes

90(49.45)

627(55.24)

The time to start oral intake, (h) (\(\overline x \pm s\))

13:16 ± 3:10

12:50 ± 3:24

Whether there is gas or stool output in ICU period, n(%)

no

167 (91.76)

1033(91.01)

yes

15(8.24)

102(8.99)

Blood potassium (mmol/L), n(%)

low

60(32.97)

422(37.18)

normal

121(66.48)

709 (62.47)

high

1(0.55)

4(0.35)

Blood calcium (mmol/L), n(%)

low

29(15.93)

155(13.66)

normal

153(84.07)

980(86.34)