Appendix 3 Subgroup analysis of different types of SSI
From: Optimal timing of surgical antimicrobial prophylaxis in laparoscopic surgery: a before-after study
No SSI (n = 1207) | Superficial SSI (n = 113) | Deep and organ space SSI (n = 77) | P value | ||
|---|---|---|---|---|---|
No SSI vs superficial SSI | No SSI vs deep and organ space SSI | ||||
Age, median, (IQR) years | 66 (52–75) | 67 (53–76) | 72 (64–78) | 0.49 | < 0.001 |
< 65, n (%) | 554 (45.9) | 50 (44.3) | 21 (27.3) | 0.74 | 0.018 |
≥ 65, n (%) | 653 (54.1) | 63 (55.7) | 56 (72.7) | ||
Male gender, n (%) | 532 (44.1) | 57 (50.4) | 17 (22.1) | 0.19 | < 0.001 |
Co-morbidities, n (%) | |||||
Diabetes mellitus | 164 (13.6) | 13 (11.5) | 15 (19.5) | 0.53 | 0.15 |
Chronic lung diseases | 57 (4.7) | 6 (5.3) | 6 (7.8) | 0.78 | 0.23 |
Cardiovascular diseases | 59 (4.9) | 7 (6.2) | 3 (3.9) | 0.54 | 0.69 |
Hypertension | 442 (36.6) | 38 (33.6) | 33 (42.9) | 0.53 | 0.27 |
Dyslipidemia | 198 (16.4) | 19 (16.8) | 14 (18.2) | 0.91 | 0.68 |
Current smoker, n (%) | 560 (46.4) | 58 (51.3) | 52 (67.5) | 0.32 | < 0.001 |
ASA score, n (%) | |||||
1 (no disturbance) | 250 (20.7) | 22 (19.5) | 7 (9.1) | Ref. | Ref. |
2 (mild disturbance) | 854 (70.8) | 82 (72.6) | 62 (80.5) | 0.73 | 0.02 |
3 (severe disturbance) | 99 (8.2) | 9 (8.0) | 8 (10.4) | 0.94 | 0.05 |
4 (life-threatening) | 4 (0.3) | 0 (0) | 0 (0) | N/A | N/A |
Wound class, n (%) | |||||
2 clean-contaminated | 1202 (99.6) | 112 (99.1) | 76 (98.7) | 0.48 | 0.27 |
3 contaminated | 5 (0.4) | 1 (0.9) | 1 (1.3) | 0.48 | 0.27 |
Emergent surgery, n (%) | 200 (16.6) | 16 (14.2) | 6 (7.8) | 0.51 | 0.04 |
Type of surgery, n (%) | |||||
Cholecystectomy | 291 (24.1) | 11 (9.7) | 5 (6.5) | Ref. | Ref. |
Gastrectomy | 294 (24.4) | 28 (24.8) | 49 (63.6) | 0.011 | < 0.001 |
Appendectomy | 140 (11.6) | 14 (12.4) | 3 (3.9) | 0.019 | 0.77 |
Colectomy | 175 (14.5) | 16 (14.2) | 9 (11.7) | 0.028 | 0.05 |
Proctectomy | 306 (25.4) | 44 (38.9) | 11 (14.3) | < 0.001 | 0.18 |
Cholecystectomy and appendectomy | 1 (0.1) | 0 (0) | 0 (0) | N/A | N/A |
Operation time, median, (IQR) min | 205 (131–285) | 229 (164–296) | 325 (271–399) | 0.015 | < 0.001 |
< 180, n (%) | 502 (41.6) | 33 (29.2) | 9 (11.7) | 0.01 | < 0.001 |
≥ 180, n (%) | 705 (58.4) | 80 (70.8) | 68 (88.3) | ||
SAP drip infusion time, median, (IQR) min | 18 (14–23) | 18 (14–25) | 17 (13–22) | 0.52 | 0.46 |
Time from SAP completion to surgical incision, median, (IQR) min | 12 (4–25) | 14 (2–31) | 17 (6–29) | 0.39 | 0.69 |
Time windows, n (%) | |||||
31–60 min | 175 (14.5) | 24 (21.2) | 18 (23.4) | Ref. | Ref. |
< 0 min | 143 (11.9) | 18 (15.9) | 5 (6.5) | 0.80 | 0.04 |
0–30 min | 861 (71.4) | 65 (57.5) | 54 (70.1) | 0.02 | 0.08 |
> 60 min | 26 (2.2) | 6 (5.3) | 0 (0) | 0.30 | N/A |
Intervention status, “yes” | 395 (32.7) | 35 (31.0) | 25 (32.5) | 0.70 | 0.83 |