Background
Methods
Study design
Sampling
Data collection and Laboratory procedures
Data analysis
Study limitations
Results
Study population and demographic characteristics
Surgical Procedure | SSI Positive | SSI negative | Total |
---|---|---|---|
Laparotomy | 17 (27.9%) | 44 (72.1%) | 61 |
Open prostatectomy | 8 (30.8%) | 18 (69.8%) | 26 |
Excisional Biopsy | 7 (30.4%) | 16 (69.4%) | 23 |
Thyroidectomy | 1 (4.8%) | 20 (95.2%) | 21 |
Appendicectomy | 3 (15%) | 17 (85%) | 20 |
Herniotomy | 0 (0.0%) | 14(100%) | 14 |
Spinal Bifida Repair | 6 (46.2%) | 7 (53.8%) | 13 |
Mastectomy | 5 (45.5%) | 6 (55.5%) | 11 |
Mayors Repair | 3 (27.3%) | 8 (62.7%) | 11 |
Amputation | 1 (12.5%) | 7 (87.5%) | 8 |
Cholecystectomy | 1 (14.3%) | 6 (85.7%) | 7 |
Thoracotomy | 4 (66.7%) | 2 (33.3%) | 6 |
Splenectomy | 1 (33.3%) | 2 (67.7%) | 3 |
Cystolithotomy | 1 (33.3%) | 2 (67.7%) | 3 |
Skull elevation | 0 (0.0%) | 3 (100%) | 3 |
Others (20) | 7 (35%) | 13 (65%) | 20 |
Total
|
65 (26%)
|
185 (74%)
|
250
|
Variable | SSI | ||||
---|---|---|---|---|---|
Yes n (%) N = 65 | No n (%) N = 185 | P value | OR | 95% CI | |
Age in years
| |||||
< 21 | 12 (18.5%) | 49 (26.4%) | 1 | ||
21-40 | 18 (27.6%) | 59 (32.9%) | 0.60 | 1.24 | 0.54-2.83 |
41-60 | 21 (32.3%) | 47 (25.4%) | 0.15 | 1.82 | 0.81-4.11 |
> 61 | 14 (21.5%) | 30 (16.2%) | 0.16 | 1.91 | 0.78-4.66 |
Sex
| |||||
Female | 26 (40%) | 108 (58.3%) | 1 | ||
Male | 39 (60%) | 77 (42.7%) | 0.01 | 2.12 | 1.19-3.70 |
Pre-morbidity
| |||||
None Diabetes | 25(38.5%) 9 (13.8%) | 167 (90.3) 1 (0.5%) | < 0.001 0.001 | 0.072 29.6 | 0.03-0.17 4.3-281 |
Hypertension | 15(23.1%) | 13 (7.0%) | 0.002 | 4.0 | 2.1-10.8 |
HIV/AIDS | 7 (10.7%) | 2 (1.0%) | < 0.001 | 11.0 | 2.6-64.2 |
Pre-morbidity
| |||||
Absent | 26 (40%) | 168 (90.8%) | 1 | ||
Present | 39 (60%) | 17 (9.2%) | < 0.001 | 14.8 | 7.3-29.95 |
Smoking
| |||||
No | 37 (56.9%) | 180 (97.3%) | 1 | ||
Yes | 28 (43.1%) | 5 (2.7%) | < 0.001 | 27 | 9.87-75.2 |
Predictors of SSI
Pre-morbid illness
History of cigarette smoking
Antimicrobial prophylaxis
Variable | Surgical site infection | ||||
---|---|---|---|---|---|
Yes n (%), N = 65 | No n (%), N = 185 | P value | OR | 95% CI | |
Preoperative duration of hospitalization
| |||||
≤ 7 days | 41 (63%) | 140 (75.7%) | 1 | ||
> 7 days | 24 (37%) | 45 (24.3%) | 0.05 | 1.82 | 0.99-3.33 |
Antimicrobial prophylaxis
| |||||
Yes | 6 (9.2%) | 35 (18.9%) | 1 | ||
No | 59 (90.8%) | 150 (81.1%) | 0.08 | 2.29 | 0.91-5.73 |
Hair removal
| |||||
Yes | 1 (1.5%) | 5 (2.7%) | 0.59 | 1.78 | 0.20-15.5 |
No | 64 (98.5%) | 180 (97.3%) | 1 | ||
ASA
| |||||
I | 30 (46.2%) | 168 ((90.8%) | 1 | ||
II | 27 (41.5%) | 16 (8.6%) | < 0.001 | 9.45 | 4.55-16.6 |
III | 8 (12.3%) | 1 (0.6%) | < 0.001 | 44.8 | 5.4-371.3 |
Skin preparation
| |||||
Iodine alone | 38 (58.5%) | 16(8.7%) | < 0.001 | 13.9 | 6.8-28.2 |
Iodine and spirit | 27 (41.5%) | 158 (86.5%) | 1 |
American Society of Anesthesiologists (ASA) classification, skin preparation, use of drain
Duration of operation
Post-operative antibiotic prophylaxis
Surgical wound classification
Variable | SSI | ||||
---|---|---|---|---|---|
Yes n (%) N = 65 | No n (%) N = 185 | P value | OR | 95% CI | |
Nature of operation
| |||||
Elective | 54 (83%) | 142 (76.7%) | 1 | ||
Emergency | 11 (17%) | 43 (23.3%) | 0.29 | 0.67 | 0.32-1.39 |
Type of anaesthesia
| |||||
GA | 56 (86.1%) | 161 (87%) | 1 | ||
SAB | 9 (13.9%) | 24 (13%) | 0.86 | 1.07 | 0.47-2.46 |
Surgeon
| |||||
Registrar | 7 (10.7%) | 32 (17.3%) | 1 | ||
Resident | 13 (20%) | 37 (20%) | 0.37 | 1.6 | 0.57-4.5 |
Specialist | 45 (69.2%) | 116 (62,7%) | 0.21 | 1.8 | 0.73-4.3 |
Use of drain
| |||||
Yes | 26 (40%) | 28 (15.1%) | < 0.001 | 3.8 | 2.0-7.14 |
No | 39 (60%) | 157 (84.9%) | 1 | ||
Wound classification
| |||||
Clean | 41(63%) | 152 (82%) | 1 | ||
Clean contaminated | 20 (30.7%) | 26 (14%) | 0.002 | 2.85 | 1.44-5.61 |
Contaminated | 4 (6.3%) | 7 (4%) | 0.25 | 2.12 | 0.59-7.59 |
Suture
| |||||
Nylon | 44 (67.7%) | 118 (63.8%) | 1 | ||
Silk | 10 (15.4%) | 9 (4.9%) | 0.16 | 2.08 | 0.73-5.94 |
Vicryl | 11 (16.9%) | 57 (30.8%) | 0.01 | 0.33 | 0.13-0.77 |
Duration of operation
| |||||
< 3 hours | 43 (66.1%) | 163 (88.1%) | 1 | ||
≥ 3 hours | 22 (33.9%) | 22 (11.9%) | < 0.001 | 3.8 | 1.92-7.48 |
Number of people in theatre
| |||||
≤ 6 | 11 (16.9%) | 137 (74%) | 1 | ||
≥ 7 | 54 (83.1%) | 48 (26%) | < 0.001 | 14 | 6.77-29 |
Multivariate logistic regression
Predictor variable | Odd ratio | 95% CI | P- value |
---|---|---|---|
Pre-morbid illness | 6.1 | 1.3-28.9 | 0.022 |
ASA Classification above I | 0.7 | 0.15-3.7 | 0.713 |
Use of drain | 3.5 | 1.4-19.3 | 0.016 |
Use of iodine alone in skin preparation | 17.6 | 6.5-48.1 | < 0.001 |
Duration of Operation ≥ 3 hrs | 3.2 | 1.1-9.3 | 0.033 |
Use of Vicryl | 2.4 | 0.78-7.2 | 0.129 |
Cigarette smoking | 9.6 | 2.4-38.3 | 0.001 |