The Effect of Time to Redebridement on 30-Day Mortality in Critically Ill Patients with NSTI

Author(s):
Jacob O’Dell; Diego Mazzotti; Christopher Guidry

Background:

Necrotizing soft tissue infections (NSTIs) are surgical emergencies which convey high mortality. The optimal time frame for initial debridement has been demonstrated to be “emergent.” In contrast, the optimal time from 1st to 2nd debridement (redebridement interval), is not definitively known, but is frequently recommended to be 24 hours.

Hypothesis:

We hypothesized that patients who received redebridement within 1 day would have a lower mortality than those who had a longer redebridement interval.

Methods:

This retrospective cohort study identified patients at a single center from January 2005 through September 2021. A deidentified database was queried for all encounters meeting the following inclusion criteria: 1 or more diagnoses of NSTI by ICD code, 2 or more debridements by CPT code, and ICU admission. The variable of interest was redebridement interval, measured in days. Primary outcome was 30-day mortality. Comorbidities and markers of illness severity were gathered. Patients were stratified into Early Redebridement (ER) and Delayed Redebridement (DR) groups by redebridement interval. Day(s) to redebridement were defined as 1 in the ER group, and 2 or more in the DR group. Chi-squared, Fisher’s exact, and Wilcoxon’s Signed Rank tests were used to detect differences between the two subgroups. Significance threshold p = 0.05

Results:

127 patients met inclusion criteria (n = 127). 38 patients received redebridement within 1 calendar day (ER: n = 38). 89 patients received redebridement after 2 or more calendar days (DR: n = 89).  There were no differences in demographics, comorbidities, ICU status, vasopressor requirements, or number of debridements between groups.  At 30 days, 6 (15.8%) patients died in the early group, compared to 3 (3.4%) in the late group (p = 0.02). A subgroup analysis of only patients requiring vasopressors showed a similar increase in mortality for patients in the ER group (24.0 vs 5.2%; p=0.01).

Conclusions:

In our study, patients who received redebridement within the recommended 1-day window sustained a higher 30-day mortality than patients who received later redebridement. This relationship was opposite to both our hypothesis and findings from prior studies. We suspect that redebridement interval is a marker of presenting illness severity. These findings support continued refinement of the paradigm for redebridement urgency in NSTI, specifically a prospective assessment of the recommended 24-hour time frame.