Reflections on the Complexity of Surgical Site Infection Prevention and Detection from an Organizational Lens

Impact of Wound Closure Technique on Surgical Site Infection After Lower Extremity Bypass Surgery

BACKGROUND

Surgical site infections (SSIs) are among the most common complications after lower extremity bypass (LEB). Both patient and hospital-related factors have been associated with SSI after LEB; however, the impact of surgical closure technique on SSI incidence remains unclear.

METHODS

Institutional electronic medical records (EMRs) were retrospectively queried for all LEB procedures performed from 2018 to 2022. Data were collected on patient demographics, medical comorbidities, operative details, wound closure techniques, and postoperative outcomes. Closure techniques included skin staples, absorbable monofilament (Monocryl), nonabsorbable monofilament (Nylon), or left open to heal by secondary intention. Logistic regression analysis was utilized to identify risk factors and calculate adjusted odds ratios (ORs) for postoperative SSI.

RESULTS

A total of 517 patients underwent LEB surgery over the study period. SSI was diagnosed in 120 (23.2%) patients over a median follow-up period of 1.5 years. The most common SSI locations were groin incision (40.0%), saphenectomy (31.7%), and leg incision (19.2%). The median onset of SSI was 18.5 d (interquartile range [IQR] 11-28 d) post-LEB surgery. Patients with SSI had higher body mass index (BMI) (28.2 [IQR 24.2-33.5] vs. 26.6 [23.1-31.5] kg/m2, P = 0.03) compared with non-SSI patients. Patient age, sex, and medical comorbidities were otherwise similar between groups. There were no differences in closure technique (79.2% vs. 78.1% staples, 18.3% vs. 19.7% Monocryl, 0.8% vs. 1.8% Nylon, 1.7% vs. 0.5% open; P = 0.53) in SSI versus non-SSI groups. On multivariate analysis, patient BMI (OR 1.04 per unit, 95% confidence interval [CI] 1.01-1.08, P = 0.02), reoperative field (OR 1.81, 95% CI 1.00-3.25, P = 0.03), and active smoking (OR 2.72, 95% CI 1.12-6.59, P = 0.048) were independently associated with increased SSI incidence. Postoperative SSI resulted in prolonged hospital length of stay (LOS) (7 vs. 6 days, P = 0.04), unplanned hospital readmission (49.2% vs. 12.3%, P < 0.001), and reoperation rates (64.7% vs. 8.1%, P < 0.001). Bypass graft infection rates were also higher among patients suffering postoperative SSI (9.2% vs. 0.0%, P < 0.001). On subset analysis of patients at increased risk of postoperative SSI, as found on multivariate modeling, there were no differences in closure technique between SSI and no SSI groups.

CONCLUSIONS

This study provides insights on wound closure techniques and postoperative SSI made available through granular, operative data that are not found in large database analyses. Surgical wound closure technique was not associated with postoperative SSI after LEB surgery, even among patients at increased risk of infection. These data support individualization of wound closure techniques among patients undergoing LEB surgery.

Relationships between predischarge and postdischarge infectious complications, length of stay, and unplanned readmissions in the ACS NSQIP database

BACKGROUND

Postoperative complications, length of index hospital stay, and unplanned hospital readmissions are important metrics reflecting surgical care quality. Postoperative infections represent a substantial proportion of all postoperative complications. We examined the relationships between identification of postoperative infection prehospital and posthospital discharge, length of stay, and unplanned readmissions in the American College of Surgeons National Surgical Quality Improvement Program database across nine surgical specialties.

METHODS

The 30-day postoperative infectious complications including sepsis, surgical site infections, pneumonia, and urinary tract infection were analyzed in the American College of Surgeons National Surgical Quality Improvement Program inpatient data during the period from 2012 to 2017. General, gynecologic, vascular, orthopedic, otolaryngology, plastic, thoracic, urologic, and neurosurgical inpatient operations were selected.

RESULTS

Postoperative infectious complications were identified in 5.2% (137,014/2,620,450) of cases; 81,929 (59.8%) were postdischarge. The percentage of specific complications identified postdischarge were 73.4% of surgical site infections (range across specialties 63.7-93.1%); 34.9% of sepsis cases (27.4-58.1%); 26.5% of pneumonia cases (18.9%-36.3%); and 53.2% of urinary tract infections (48.3%-88.0%). The relative risk of readmission among patients with postdischarge versus predischarge surgical site infection, sepsis, pneumonia, or urinary tract infection was 5.13 (95% confidence interval: 4.90-5.37), 9.63 (8.93-10.40), 10.79 (10.15-11.45), and 3.32 (3.07-3.60), respectively. Over time, mean length of stay decreased but postdischarge infections and readmission rates significantly increased.

CONCLUSION

Most postoperative infectious complications were diagnosed postdischarge. These were associated with an increased risk of readmission. The trend toward shorter length of stay over time was observed along with an increase both in the percentage of infections detected after discharge and the rate of unplanned related postoperative readmissions over time. Postoperative surveillance of infections should extend beyond hospital discharge of surgical patients.