Impact of prehospital orientation of septic shock on 30-day mortality

Background: In order to reduce sepsis mortality, early treatment implementation and referral to the most appropriate ward (emergency department (ED) or intensive care unit (ICU) are recommended. This multicentre retrospective study aims to study the relationship between 30-day mortality and the admission mode to ICU or ED among patients with septic shock cared for by a prehospital mobile Intensive Care Unit (MICU). Methods: From May 2016 to December 2022, septic shock patients cared for by a prehospital MICU were retrospectively analysed. To assess the relationship between 30-day mortality rate and the admission mode, a multivariate logistic regression after Inverse Probability Treatment Weighting (IPTW) propensity score matching was performed. Results: Among the 587 patients analysed, pulmonary, urinary and digestive infections were the main sepsis aetiology: 42%, 26% and 17% respectively. The overall 30-day mortality rate was 30%. Three-hundred and twenty-seven patients (58%) were admitted to ICU and 260 (42%) to the ED. On matched population, the multivariate analysis including the followings potential confounders: prehospital fluid expansion, norepinephrine administration, antibiotic therapy, age, chronic obstructive pulmonary disease, chronic renal failure, diabetes mellitus, cancer history, hypertension, chronic heart failure, coronary artery disease, hospitalization in the previous 3 months, SAPS-2, management in rural area and prehospital duration, an aRR=1.05 [1.00-1.09] (p=0.025) between 30-day mortality and ED admission. Conversely, the multivariate analysis with the same confounders found aRR=0.90 [0.86-0.95] between 30-day mortality and ICU admission. Conclusion: This study highlighted a positive relationship between ED admission and 30-day mortality of patients in septic shock cared for by a prehospital MICU suggesting a possible negative effect of ED admission whereas a direct ICU admission may be beneficial.