Table 3 Factors affecting the shorter time to first flatus (early bowel recovery)

Groups

 Collagen

1

1

 Control

2.12 (1.21–3.72)

< 0.01^a

2.02 (1.12–3.67)

0.02

Sex

 Male

1

 Female

1.06 (0.62–1.82)

0.83

Age

 ≥ 65

1.36 (0.78–2.35)

0.28

 < 65

1

BMI

 ≥ 25

1.15 (0.67–1.97)

0.61

 < 25

1

Smoking

 Yes

0.47 (0.18–1.20)

0.11^a

0.52 (0.19 − 1.39)

0.19

 No

1

1

Comorbidity

 Yes

0.92 (0.53 − 1.59)

0.76

 No

1

 CCI > 5

1.60 (0.93 − 2.77)

0.09^a

1.51 (0.84 − 2.70)

0.17

 CCI ≤ 5

1

1

History of abdominal surgery

 Yes

0.99 (0.51–1.90)

0.97

 No

1

Tumor

 Benign

1

 Malignant

0.85 (0.45–1.60)

0.61

Location

 Left

1

1

 Right

2.10 (0.99–4.41)

0.05^a

1.95 (0.91–4.15)

0.08

Surgery

 Combined surgery

4.01 (1.30–12.41)

0.01^a

3.83 (1.18–12.46)

0.03

 Isolated surgery

1

1

Complication

 Yes

1.90 (0.92–3.93)

< 0.01^a

1.53 (0.69–3.37)

0.29

 No

1

1

Dosage of using IV analgesic

 Dosage > 3

2.29 (1.33–3.97)

< 0.01^a

1.92 (1.07–3.42)

0.03

 Dosage ≤ 3

1

1