TABLE 4.
Outcomes | Event Rate n (%) | Adjusted Odds Ratios (95% Confidence Interval) | |||||
---|---|---|---|---|---|---|---|
Baseline (n = 2615) | Implementation (n = 1122) | Postimplementation (n = 1400) | |||||
P Value | Baseline | Implementation | Postimplementation | ||||
Any SSI | 206 (7.9%) | 74 (6.6%) | 98 (7.1%) | 0.347 | 1.00 (REF) | 0.84 (0.59, 1.20) | 0.92 (0.72, 1.17) |
Superficial SSI | 95 (3.6%) | 28 (2.5%) | 34 (2.4%) | 0.071 | 1.00 (REF) | 0.69 (0.40, 1.20) | 0.70 (0.49, 1.02)+ |
Deep SSI | 21 (0.8%) | 7 (0.6%) | 7 (0.5%) | 0.421 | 1.00 (REF) | 0.80 (0.34, 1.86) | 0.66 (0.31, 1.41) |
Organ space SSI | 109 (4.2%) | 42 (3.8%) | 64 (4.6%) | 0.572 | 1.00 (REF) | 0.92 (0.62, 1.35) | 1.12 (0.82, 1.52) |
Overall morbidity | 369 (14.1%) | 128 (11.4%) | 162 (11.6%) | 0.102 | 1.00 (REF) | 0.82 (0.59, 1.14) | 0.86 (0.65, 1.14) |
Extended LOS* | 596 (22.8%) | 241 (21.5%) | 268 (19.1%) | 0.121 | 1.00 (REF) | 0.99 (0.75, 1.33) | 0.90 (0.71, 1.14) |
Readmission | 235 (9.0%) | 89 (7.9%) | 133 (9.5%) | 0.408 | 1.00 (REF) | 0.89 (0.69, 1.15) | 1.08 (0.87, 1.35) |
P values from design-corrected chi-square tests with responses clustered by hospital.
Statistical significance of odds ratio estimates is denoted as follows:
P = 0.06.
Notes: Based on 4985 to 5315 observations (sample size varies by outcome measure) based on missing data and preexisting complications. Implementation and postimplementation effects are as compared to the Baseline period. SSI subtypes can co-occur, therefore subtype rates do not add up to the any SSI rate.
Models adjusted for patient age, American Society of Anesthesiologists classification, BMI category (underweight, normal, overweight, or obese), procedure type (proctectomy vs. colectomy), and open procedure (vs. laparoscopic) except for extended LOS (proctectomy indicator not included). The underweight BMI category was excluded from the deep incisional SSI model due to separation of data points with respect to the outcome.
Extended LOS defined as surgical length of stay >6 d for colectomy and >8 d for proctectomy based on the 75th percentile of LOS in these elective procedure types in the NSQIP PUF for 2015–2016.
LOS indicates length of stay; REF, referent; SSI, surgical site infection.