Hyperbaric oxygen treatment in the management of necrotising soft-tissue infections: results from a Danish nationwide registry study.

Objectives: Application of hyperbaric oxygen (HBO) treatment in the multidisciplinary setting of necrotising soft-tissue infection (NSTI) is debated as a considerable number of studies are of low quality with marked prognostication bias due to inadequately addressing disease severity. The objective of this study was to associate HBO treatment with mortality in patients with NSTI including disease severity as a prognostic variable.

Design: Nationwide population-based register study.

Setting: Denmark.

Participants: Danish residents with NSTI patients between January 2011 and June 2016.

Primary And Secondary Outcome Measures: Thirty-day mortality was compared between patients receiving and patients not receiving HBO treatment using inverse probability of treatment weighting and propensity-score matching with predetermined variables (age, sex and weighted Charlson comorbidity score, presence of septic shock and Simplified Acute Physiology Score II (SAPS II)).

Results: A total of 671 NSTI patients were included with a median age of 63 (52-71), 61% male sex, 30% had septic shock and a median SAPS II of 46 (34-58). Patients who received HBO treatment (n=266) were younger and had lower SAPS II, but a larger fraction had septic shock compared with patients not receiving HBO treatment. Overall, all-cause 30-day mortality was 19% (95% CI 17% to 23%). The statistical models were in general acceptably balanced with covariates reaching <0.1 absolute standardised mean differences and patients receiving HBO treatment were associated with lower 30-day mortality (OR 0.40, 95% CI 0.30 to 0.53, p<0.001).

Conclusions: In analyses using inverse probability of treatment weighting and propensity score analysis, patients treated with HBO treatment were associated with improved 30-day survival.