Table 4 Results of bivariable and multivariable Cox proportional hazards regression analyses, January 1, 2019, to December 31, 2022 (N = 386)

Sex

Male

44

195

0.9 [0.6, 1.5]

1.1 [0.70, 1.99]

Female

32

115

1

1

Duration of symptoms

> 3days

62

192

2.9 [1.3, 4.3]*

2.2 [1.15, 4.02]*

≤ 3days

14

118

1

1

Presence of comorbidity

Yes

30

74

1.14 [0.72, 1.82]

0.8 [0.49, 1.38]

No

46

236

1

Abdominal tenderness

No tenderness

20

183

1

Diffuse tenderness

56

127

1.5 [0.89, 2.55]

0.72 [0.20–4.03]

Fever

Yes

26

69

1.4 [0.89, 2.32]**

1.5 [0.89, 2.53]

No

50

241

1

1

abnormal leukocyte count

Yes

35

169

0.7 [0.46, 1.14]**

0.9 [0.49, 1.50]

Normal

41

141

1

1

Diagnosis

Large bowel obstruction

64

288

1.0 [0.6–1.7]

1.0 [0.55, 1.81]

viscus perforation

12

22

1.6 [0.9, 3.2]

1.2 [0.58, 2.92]

Preoperative antibiotic use

Yes

18

145

1.4 [0.8, 2.4]

1

No

58

165

0.9 [0.66, 2.10]

Preoperative vasopressor use

Yes

41

41

2.2 [1.4, 3.5] *

1.8 [1.11, 2.98] *

No

35

269

1

1

Preoperative hypotension

Yes

9

15

1.8 [0.9, 3.6]

1.1 [0.54, 2.51]

No

67

295

1

1

Preoperative sepsis

Yes

29

37

1.8 [1.1, 2.9]*

1.8 [1.05, 3.17]*

No

47

273

1

Degree of peritoneal contamination

Generalized

14

122

3.5 [1.24, 9.6]*

3.0 [0.96, 9.50]

Localized or none

62

188

1

Pus or faecal matter in peritoneal cavity

Yes

51

157

1.9 [1.2,3.0]*

1.7 [0.91, 2.93]

No

25

153

1

1

Duration of procedures

≥ 1 h

61

119

1.96 [1.1, 3.5]*

1.7 [0.82, 3.40]

< 1 h

15

191

1

1

Bowel ischemia

Yes

57

129

1.4 [0.81, 2.40]**

1.1 [0.54, 2.23]

No

19

181

1

1

Site of Postop care

ICU

20

25

1.96 [1.2, 3.3] *

2.0 [1.23, 3.49]*

PACU

56

285

1

1