Table 1. Basic clinical characteristics of preoperative prophylaxis alone group and pre- plus intraoperative prophylaxis group.
| Variables | Full cohort (N=1,840) | Preoperative only (N=361) | Pre + intraoperative (N=1,479) | P |
|---|---|---|---|---|
| Age, years | 54.24±12.81 | 52.02±14.24 | 54.78±12.38 | <0.01 |
| <60 | 1,147 (62.3%) | 244 (67.6%) | 903 (61.1%) | 0.02 |
| ≥60 | 693 (37.7%) | 117 (32.4%) | 576 (38.9%) | |
| Gender | ||||
| Female | 778 (42.3%) | 161 (44.6%) | 617 (41.7%) | 0.32 |
| Male | 1,062 (57.7%) | 200 (55.4%) | 862 (58.3%) | |
| BMI (kg/m2) | 23.89±3.52 | 24.22±3.77 | 23.81±3.46 | 0.06 |
| <24 | 998 (54.2%) | 187 (51.8%) | 811 (54.8%) | 0.30 |
| ≥24 | 842 (45.8%) | 174 (48.2%) | 668 (45.2%) | |
| Smoking status | ||||
| No | 1,169 (65.5%) | 228 (63.2%) | 941 (63.6%) | 0.58 |
| Yes | 671 (36.5%) | 133 (36.8%) | 538 (36.4%) | |
| Operation location | ||||
| Head and neck | 583 (31.7%) | 160 (44.3%) | 423 (28.6%) | <0.001 |
| Chest | 365 (19.8%) | 85 (23.5%) | 280 (18.9%) | |
| Abdomen | 729 (39.6%) | 102 (28.3%) | 627 (42.4%) | |
| Limbs and spine | 163 (8.9%) | 14 (3.9%) | 149 (10.1%) | |
| Duration of surgery (min) | 352.72±127.34 | 323.06±129.88 | 359.97±125.70 | <0.001 |
| <360 | 1,148 (62.4%) | 257 (71.2%) | 891 (60.2%) | <0.001 |
| ≥360 | 692 (37.6%) | 104 (28.8%) | 588 (39.8%) | |
| Hypertension | ||||
| No | 1,241 (67.4%) | 239 (66.2%) | 1,002 (67.7%) | 0.83 |
| Yes | 599 (32.6%) | 122 (33.8%) | 477 (32.3%) | |
| Blood glucose control | ||||
| <6.1 mmol/L | 1,421 (77.2%) | 261 (72.3%) | 1,160 (78.4%) | 0.01 |
| ≥6.1 mmol/L | 419 (22.8%) | 100 (27.7%) | 319 (21.6%) | |
| Hemoglobin (g/L) | 133.81±26.92 | 135.66±28.87 | 133.35±26.41 | 0.15 |
| WBC (×109/L) | 7.45±3.46 | 8.17±4.44 | 7.28±3.16 | <0.001 |
| ≤10 | 1,590 (86.4%) | 293 (81.2%) | 1,297 (87.7%) | <0.01 |
| >10 | 250 (13.6%) | 68 (18.8%) | 182 (12.3%) | |
| ASA score | ||||
| ≤2 | 1,763 (95.8%) | 342 (94.7%) | 1,421 (96.1%) | 0.25 |
| >2 | 77 (4.2%) | 19 (5.3%) | 58 (3.9%) | |
| Wound class | ||||
| I–II | 320 (17.4%) | 140 (38.8%) | 180 (12.2%) | <0.001 |
| III–IV | 1,520 (82.6%) | 221 (61.2%) | 1,299 (87.8%) | |
| Intraoperative blood loss | ||||
| No | 1,178 (64.0%) | 261 (72.3%) | 917 (62.0%) | <0.001 |
| Yes | 662 (36.0%) | 100 (27.7%) | 562 (38.0%) | |
| Blood supply | ||||
| No | 1,355 (73.6%) | 292 (80.9%) | 1,063 (71.9%) | <0.001 |
| Yes | 485 (26.4%) | 69 (19.1%) | 416 (28.1%) | |
| SSI | ||||
| No | 1,780 (96.7%) | 341 (94.5%) | 1,439 (97.3%) | <0.01 |
| Yes | 60 (3.3%) | 20 (5.5%) | 40 (2.7%) | |
BMI, body mass index; WBC, white blood cell; ASA, American Society of Anesthesiologists; SSI, surgical site infection.