Table 2.
Characteristics of patients, operations and SSIs
| Risk factors | HPRO | KPRO | OPRO | OMS | ||||
|---|---|---|---|---|---|---|---|---|
| SSI | SSI | SSI | SSI | |||||
| No | Yes | No | Yes | No | Yes | No | Yes | |
| n = 552 | n = 32 | n = 2961 | n = 14 | n = 342 | n = 18 | n = 2961 | n = 228 | |
| Duration of operation (min) | ||||||||
| Mean | 140 | 155 | 110 | 120 | 60 | 65 | 120 | 125 |
| SD | 42 | 43 | 36 | 36 | 16 | 16 | 38 | 38 |
| p value | 0.0503 | 0.3123 | 0.1971 | 0.0556 | ||||
| P75 (min) | 160 | 130 | 94 | 135 | ||||
| Age (years) | ||||||||
| Mean | 67.0 | 69.1 | 66.8 | 69.0 | 49.8 | 46.7 | 47.9 | 62.0 |
| SD | 18 | 18 | 18 | 18 | 16 | 16 | 16 | 18 |
| p value | 0.5215 | 0.6564 | 0.4235 | < 00001 | ||||
| The duration of the pre-hospitalisation (days) | ||||||||
| Mean | 6 | 6 | 6 | 6 | 4 | 4 | 3 | 4 |
| SD | 7 | 7 | 7 | 7 | 6 | 6 | 4 | 4 |
| p value | 1.0000 | 1.0000 | 1.0000 | 0.0003 | ||||
| Gender (%) | ||||||||
| Male | 55.3 | 53.1 | 58.1 | 57.1 | 51.5 | 55.6 | 70.6 | 64.5 |
| Female | 44.7 | 46.9 | 41.9 | 42.9 | 48.5 | 44.4 | 29.4 | 35.5 |
| p value | 0.8139 | 0.9413 | 0.7348 | 0.0520 | ||||
| OR (95%CI) | 0.8 (0.57–1.19) | 0.07 (0.04–0.11) | 0.7 (0.5–1.2) | 1.1 (0.9–1.3) | ||||
| Cleanliness of the surgical site (%) | ||||||||
| Clean, clean-contaminated | 99.8 | 100.0 | 99.6 | 100.0 | 99.7 | 100.0 | 93.0 | 82.0 |
| Contaminated, dirty | 0.2 | 0.0 | 0.4 | 0.0 | 0.3 | 0.0 | 7.0 | 18.0 |
| p value | 0.8096 | 0.8155 | 0.8183 | < 0.0001 | ||||
| OR (95%CI) | 1.0 (0.61–1.66) | 1.00 (0.48–2.11) | 1.00 (0.51–1.96) | 0.88 (0.72–1.1) | ||||
| State of the patient in the ASA scale (%) | ||||||||
| 1 or 2 | 67.6 | 53.1 | 69.8 | 42.9 | 76.9 | 72.2 | 83.0 | 86.0 |
| 3 or 4 or 5 | 32.4 | 46.9 | 30.2 | 57.1 | 23.1 | 27.8 | 17.0 | 14.0 |
| p value | 0.0916 | 0.0349 | 0.6474 | 0.2503 | ||||
| OR (95%CI) | 0.8 (0.9–3.8) | 3.0 (1.1–8.9) | 1.3 (0.4–3.7) | 0.8 (0.5–1.2) | ||||
| Incidence rate (%) | 5.8 | 5.4 | 5.3 | 7.7 | ||||
| Clinical form of the SSI, n (%) | ||||||||
| Superficial | 16 (50.0) | 12 (85.7) | 15 (83.3) | 97 (42.5) | ||||
| Deep | 14 (43.8) | 2 (14.3) | 3 (16.7) | 125 (54.8) | ||||
| Organ/space | 2 (6.3) | 0 (0.0) | 0 (0.0) | 6 (2.6) | ||||
| Time of detection of SSI, n (%) | ||||||||
| During hospital stay | 7 (21.9) | 4 (28.6) | 4 (22.2) | 139 (61.0) | ||||
| Post-disleftge | 12 (37.5) | 7 (50.0) | 14 (77.8) | 49 (21.5) | ||||
| Re-hospitalisation | 13 (40.6) | 3 (21.4) | 0 (0.0) | 40 (17.5) | ||||
ASA the American Society of Anesthesiologists physical status classification, HPRO hip endoarthroplasty, KPRO knee endoarthroplasty, OMS other musculoskeletal, OPRO other prostheses, OR (95%CI) odds ratio and 95% confidence interval, P75 75th percentile of duration of operation, SD standard deviation, SSI surgical site infections