Supplemental Table 1: Clinical characteristics of all patients in this study.
Characteristics Development cohort (N= 493) Validation cohort (N= 130) P
Outcome (n, %)
Good 392 (79.51) 100 (76.92) 0.5191
Poor 101 (20.49) 30 (23.08)
Age (n, %)
≥80 years 29 (5.88) 9 (6.92) 0.6592
<80 years 464 (94.12) 121 (93.08)
Sex (n, %)
Male 308 (62.47) 76 (58.46) 0.4026
Female 185 (37.53) 54 (41.54)
Smoke (n, %)
No 398 (80.73) 104 (80.00) 0.8515
Yes 95 (19.27) 26 (20.00)
Drink (n, %)
No 417 (84.58) 110 (84.62) 0.9930
Yes 76 (15.42) 20 (15.38)
Hypertension (n, %)
No 418 (84.79) 110 (84.62) 0.9614
Yes 75 (15.21) 20 (15.38)
Diabetes (n, %)
No 464 (94.12) 121 (93.08) 0.6592
Yes 29 (5.88) 9 (6.92)
Past abdominal surgery history (n, %)
No 360 (73.02) 95 (73.08) 0.9900
Yes 133 (26.98) 35 (26.92)
Cardiovascular disease (n, %)
No 466 (94.52) 126 (96.92) 0.2630
Yes 27 (5.48) 4 (3.08) Chronic kidney disease (n, %)
No 491 (99.59) 130 (100) 1.0000
Yes 2 (0.41) 0 (0)
COPD (n, %)
No 486 (98.58) 128 (98.46) 1.0000
Yes 7 (1.42) 2 (1.54)
Core temperature (°C) (n, %)
<36.0 11 (2.23) 3 (2.31) 0.5108
36.0–38.0 414 (83.98) 104 (80.00)
>38.0 68 (13.79) 23 (17.69)
Heart rate (beats/min) (n, %)
<60 4 (0.81) 3 (2.31) 0.1465
60–100 280 (56.80) 80 (61.54)
>100 209 (42.39) 47 (36.15)
Respiratory rate (breaths/min) (n, %)
<22 320 (64.91) 83 (63.85) 0.8610
22–29 145 (29.41) 42 (32.31)
30–35 21 (4.26) 4 (3.08)
>35 7 (1.42) 1 (0.77)
MAP (mmHg) (mean ± SD) 90.92 ± 14.75 90.09 ± 13.40 0.5655
NRS (mean ± SD) 2.68 ± 1.33 2.73 ± 1.11 0.6664
Source of infection (n, %)
Appendix 165 (33.47) 36 (27.69) 0.7812
Colon 51 (10.34) 15 (11.54)
Small bowel 81 (16.43) 18 (13.85)
Stomach 28 (5.68) 8 (6.15)
Duodenum 43 (8.72) 13 (10.00)
Gallbladder 120 (24.34) 39 (30.00)
Other 5 (1.01) 1 (0.77) Surgical approach (n, %)
Endoscope 278 (56.39) 75 (57.69) 0.7897
Open belly 215 (43.61) 55 (42.31)
Type of surgery* (n, %)
Emergency 23 (4.67) 2 (1.54) 0.2148
Urgent 100 (20.28) 26 (20.00)
Semi-urgent 111 (22.52) 33 (25.38)
Non-urgent 108 (21.91) 21 (16.15)
Planned 151 (30.63) 48 (36.92)
Time from symptoms to hospital (h) (mean ± SD) 47.78 ± 42.32 45.11 ± 37.58 0.5131
Postoperative
hospital stay (days) (mean ± SD) 10.51 ± 8.15 11.67 ± 9.19 0.1605Operation time (h) (mean ± SD) 2.46 ± 1.14 2.49 ± 1.06 0.8044
MEWS (mean ± SD) 3.03 ± 1.50 2.87 ± 1.29 0.2166
APACHE II score (mean ± SD) 7.01 ± 4.99 7.21 ± 4.89 0.6786
SOFA score (mean ± SD) 1.87 ± 1.99 1.99 ± 2.01 0.5213
AAST grade surgery (n, %)
1 161 (32.66) 37 (28.46) 0.7173
2 110 (22.31) 35 (26.92)
3 155 (31.44) 40 (30.77)
4 42 (8.52) 13 (10.00)
5 25 (5.07) 5 (3.85)
*Emergency surgery: the operation was performed within 2 h; Urgent surgery: the operation was performed within 4 h; Semi-urgent surgery: the operation was
performed within 8 h; Non-urgent surgery: the operation was performed within 24 h.
AAST: American Association for the Surgery of Trauma; COPD: Chronic obstructive pulmonary disease; MAP: Mean arterial pressure; NRS: Numeric rating scale;
MEWS: Modified Early Warning Score; SOFA: Sequential organ failure assessment;
APACHE II: Acute Physiology and Chronic Health Evaluation II.
Supplemental Table 2: Results of univariate and multivariable logistic regression for the analysis of variables associated with poor outcome.
Variables
Univariable logistic regression Multivariable logistic regression*
OR (95% CI) P OR (95% CI) P
Age 1.034 (1.021 to 1.047) <0.0001 1.018 (1.002 to 1.034) 0.0270
Sex
Male 1.000 (reference) – –
Female 0.766 (0.482 to 1.217) 0.2595 – –
Anatomical related AAST grade
1 1.000 (reference) – 1.000 (reference)
2 2.76 (1.212 to 6.284) 0.0156 1.645 (0.668 to 4.052) 0.2790
3 4.243 (2.015 to 8.933) 0.0001 2.012 (0.880 to 4.597) 0.0973
4 12.474 (5.161 to 30.148) <0.0001 3.959 (1.443 to 10.865) 0.0076
5 79.221 (22.790 to 275.386) <0.0001 10.591 (2.659 to 42.185) 0.0008
Physiological related
MEWS 1.465 (1.275 to 1.683) <0.0001 – –
SOFA score 1.594 (1.413 to 1.798) <0.0001 1.322 (1.147 to 1.522) 0.0001
APACHE II score 1.197 (1.142 to 1.255) <0.0001 – –
Comorbidities related Hypertension
No 1.000 (reference) – –
Yes 1.275 (0.712 to 2.281) 0.4137 – –
Diabetes
No 1.000 (reference) – –
Yes 1.013 (0.401 to 2.559) 0.9777 – –
Cardiovascular disease
No 1.000 (reference) – –
Yes 1.385 (0.569 to 3.373) 0.4728 – –
Chronic kidney disease
No 1.000 (reference) – –
Yes 3.91 (0.242 to 63.057) 0.3365 – –
COPD
No 1.000 (reference) – –
Yes 0.644 (0.077 to 5.406) 0.6852 – –
Surgical related Surgical approach
Endoscope 1.000 (reference) 1.000 (reference)
Open belly 9.845 (5.613 to 17.268) <0.0001 5.576 (2.493 to 10.565) <0.0001 Past abdominal surgery history
No 1.000 (reference) – –
Yes 2.108 (1.329 to 3.345) 0.0015 – –
Type of surgery (n, %)
Emergency 2.565 (0.947 to 6.950) 0.0639 – –
Urgent 1.654 (0.860 to 3.182) 0.1319 – –
Semi-urgent 1.885 (1.007 to 3.526) 0.0474 – –
Non-urgent 1.587 (0.832 to 3.025) 0.1610 – –
Planned 1.000 (reference) – – –
Operation time 1.704 (1.402 to 2.070) <0.0001 1.321 (1.044 to 1.672) 0.0202