Healthcare trajectory of critically ill patients with necrotizing soft tissue infections: a multicenter retrospective cohort study using the clinical data warehouse of Greater Paris University Hospitals.

Background: Necrotizing skin and soft tissue infections (NSTIs) are rare but serious and rapidly progressive infections characterized by necrosis of subcutaneous tissue, fascia and even muscle. The care pathway of patients with NSTIs is poorly understood. A better characterization of the care trajectory of these patients and a better identification of patients at risk of a complicated evolution, requiring prolonged hospitalization, multiple surgical re-interventions, or readmission to the intensive care unit (ICU), is an essential prerequisite to improve their care. The main objective of this study is to obtain large-scale data on the care pathway of these patients. We performed a retrospective multicenter observational cohort study in 13 Great Paris area hospitals, including patients hospitalized between January 1, 2015 and December 31, 2019 in the ICU for surgically confirmed NSTIs.

Results: 170 patients were included. The median duration of stay in ICU and hospital was 8 (3-17) and 37 (14-71) days, respectively. The median time from admission to first surgical debridement was 1 (0-2) day but 69.9% of patients were re-operated with a median of 1 (0-3) additional debridement. Inter-hospital transfer was necessary in 52.4% of patients. 80.2% of patients developed organ failures during the course of ICU stay with 51.8% of patients requiring invasive mechanical ventilation, 77.2% needing vasopressor support and 27.7% renal replacement therapy. In-ICU and in-hospital mortality rates were 21.8% and 28.8%, respectively. There was no significant difference between patients with abdomino-perineal NSTIs (n = 33) and others (n = 137) in terms of in-hospital or ICU mortality. Yet, immunocompromised patients (n = 43) showed significantly higher ICU and in-hospital mortality rates than non-immunocompromised patients (n = 127) (37.2% vs. 16.5%, p = 0.009, and 53.5% vs. 20.5%, p < 0.001). Factors associated with a complicated course were the presence of a polymicrobial infection (adjusted odds ratio [aOR = 3.18 (1.37-7.35); p = 0.007], of a bacteremia [aOR = 3.29 (1.14-9.52); p = 0.028] and a higher SAPS II score [aOR = 1.05 (1.02-1.07); p < 0.0001]. 62.3% of patients were re-hospitalized within 6 months.

Conclusion: In this retrospective multicenter study, we showed that patients with NSTI required complex management and are major consumers of care. Two-thirds of them underwent a complicated hospital course, associated with a higher SAPS II score, a polymicrobial NSTI and a bacteremia.