Risk Factors Associated with Readmission following Surgical Management of Necrotizing Soft Tissue Infections

Author(s):
Hayoung Park; Ashkan Moazzez; Chris de Virgilio; Brant Putnam; Angela L. Neville M.D.; Dennis KIM

Background:

Aggressive surgical debridement remains the mainstay of therapy for patients with necrotizing soft tissue infections (NSTIs). The complex pathophysiology of NSTIs, together with host and healthcare associated factors, place patients at an increased risk for postoperative complications, including readmission to hospital.

Hypothesis:

The objective of this study was to identify potentially modifiable risk factors associated with readmission following surgical management of NSTIs.

Methods:

Patients with a postoperative diagnosis of necrotizing fasciitis, gas gangrene or Fournier’s gangrene were extracted from the NSQIP database from 2011-2016.  Patients who underwent an elective, outpatient or non-emergent operation were excluded. Bivariate and multiple logistic regression analyses were performed to evaluate patient, clinical, and perioperative variables associated with readmission.

Results:

There were 2,325 patients who underwent operative management of NSTI, of which 168 patients (7.2%) were readmitted to hospital. On bivariate analysis, there were no significant differences between groups regarding demographics, comorbidities, transfer status, premorbid functional status, or discharge disposition. Patients who were readmitted had a shorter overall length of stay (LOS, days) (17 ± 15 vs. 12 ± 6, p<0.001) and experienced a greater number of postoperative complications including superficial surgical site infection (sSSI) (p=0.02), pulmonary emboli (PE) (p=0.003), urinary tract infection (p<0.001), and postoperative sepsis (p=0.008). On mutivariate logistic regression analysis, sSSIs (OR 2.7; 95% CI 1.1-6.4, p=0.03), PE (OR 7.6; 95% CI 2.4-24.3, p<0.001), postoperative sepsis (OR 1.7; 95% CI 1.2-2.4, p=0.006), and LOS (OR 0.95, 0.94-0.97, p<0.001) were independently associated with an increased risk of readmission. Recurrent NSTI, infectious wound complications and PE were the most common diagnoses for readmission.

Conclusions:

Venous thromboembolic events and postoperative infectious complications are associated with an increased risk of 30-day readmission following surgical management of NSTIs. Future studies should consider evaluating thromboembolism prophylaxis and antimicrobial stewardship practices among surgeons caring for patients with NSTIs in an effort to decrease hospital readmissions and improve outcomes.