Table 3 Outcome parameters. For binary data, the number (n) and proportion (%) of patients are listed with the odds ratio and 95% confidence interval (CI). p-values were calculated using Chi-square or Fischer’s exact tests, as appropriate. Numerical data are listed as median with interquartile range (IQR), and p-values were calculated using non-parametric two-sided Mann-Whitney U tests. For the comprehensive complication index, data are listed as mean with standard deviation (SD) and the p-value was calculated using a parametric two-sided student’s t-test. Complications up to three months post surgery were included. GI: gastro-intestinal, GT: gastric tube. TPN: total parenteral nutrition. ICU: intensive care unit

Hospitalization

 Length of stay in days, median (IQR)

8 (6-10.75)

7 (6–10)

8 (5.5–13)

—

0.384

 ICU stay in days, median (IQR)

1 (0–1)

0 (0–1)

1 (0–1)

—

0.051

 Readmission, n (%)

17 (18.48)

15 (25.42)

2 (6.06)

5.28 (1.22–24.31)

0.025

 Readmission stay in days, median (IQR)

7 (2.5-8)

7 (2–8)

7.5 (7–8)

—

0.654

Complications (all)

 Complications, n (%)

169 (100)

109 (64.50)

60 (35.50)

 Patients with complications, n (%)

63 (68.48)

42 (71.19)

21 (63.64)

1.41 (0.58–3.31)

0.455

 Number of complications per patient, median (IQR)

1 (0–3)

1 (0–3)

1 (0–3)

—

0.615

 CDC grade, median (IQR)

II (I-II)

II (I-IIIa)

II (I-II)

—

0.1736

  CDC grade per patient, median (IQR)

II (0-IIIa)

II (0-IIIa)

II (0-II)

—

0.217

 CDC grade, n (%)

  I

36 (39.13)

22 (37.29)

14 (42.42)

0.81 (0.33–2.02)

  II

44 (47.83)

29 (49.15)

15 (45.45)

1.16 (0.49–2.80)

  IIIa

23 (25.00)

18 (30.51)

5 (15.15)

2.46 (0.83–6.56)

  IIIb

6 (6.52)

5 (8.47)

1 (3.03)

2.96 (0.37–35.88)

  IVa

3 (3.26)

1 (1.69)

2 (6.06)

0.27 (0.02–2.40)

  IVb

1 (1.09)

1 (1.69)

0 (0.00)

—

  V

3 (3.26)

1(1.69)

2 (6.06)

0.27 (0.02–2.40

  Comprehensive complication index, mean (± SD)

22.29 (± 22.47)

22.73 (± 20.57)

21.49 (± 25.95)

—

0.803

GI complications

 GI complications, n (%)

25 (100)

18 (72.00)

7 (28)

—

 Patients with GI complications, n (%)

23 (25.00)

16 (27.12)

7 (21.21)

1.38 (0.51–3.54)

0.530

 Complication, n (%)

  Peritonitis

1 (1.09)

1 (1.69)

0 (0.00)

—

  Bleeding at anastomosis

1 (1.09)

1 (1.69)

0 (0.00)

—

  Paralytic ileus

16 (17.39)

11 (18.64)

5 (15.15)

1.28 (0.42–3.60)

  Mechanical ileus

5 (5.43)

3 (5.08)

2 (6.06)

0.83 (0.16–4.88)

  Dehiscence

1 (1.09)

1 (1.69)

0 (0.00)

—

  Total blowout

1 (1.09)

1 (1.69)

0 (0.00)

—

GI treatments

 GI treatments, n (%)

31 (100)

22 (70.97)

9 (29.03)

 Patients with GI treatments, n (%)

22 (23.91)

15 (25.42)

7 (21.21)

1.27 (0.46–3.26)

0.650

 GI treatment

  Gastric tube, n (%)

15 (16.30)

9 (15.25)

6 (18.18)

0.81 (0.26–2.65)

0.715

  GT reinsertion duration in days, median (IQR)

3 (1-4.25)

3 (1.5–4.75)

3 (0-6.5)

0.729

 Medication, n (%)

12 (13)

9 (15.25)

3 (9.09)

1.80 (0.51–6.53)

0.527

 Explorative laparotomy, n (%)

1 (1.09)

1 (1.69)

0 (0.00)

—

> 0.999

 TPN, n (%)

3 (3.26)

3 (5.08)

0 (0.00)

—

0.550

GI functional outcome parameters

 Time to intake in days, median (IQR)

1 (1–1)

1 (1–2)

1 (1–1)

0.506

 Time to flatus in days, median (IQR)

3 (2–4)

3 (2–4)

3 (2–4)

—

0.550

 Time to defecation in days, median (IQR)

5 (4–6)

5 (4–6)

5 (4–7)

—

0.898

 Time to drain ex in days, median (IQR)

4.5 (3–6)

4 (3–6)

5 (3.25–7.75)

—

0.350