Relationship between prehospital modified Charlson Comorbidity Index and septic shock 30-day mortality

In the prehospital setting, early identification of septic shock (SS) at risk of poor outcome is mainly based on clinical vital signs alteration evaluation. The Charlson Comorbidity Index (CCI) is an in-hospital tool used for burden of co-morbidity assessment. We report the relationship between the modified prehospital CCI, and 30-day mortality of SS patients initially cared for in the prehospital setting by a mobile ICU (MICU).

SS patients defined according to the 2016 sepsis-3 conference cared for by MICU between February 2017 and December 2021 were retrospectively analysed. The modified prehospital CCI calculation was based on the available comorbid conditions collected in the prehospital setting. A threshold of ≥5, was chosen according to previous results.

Five-hundred and twenty-nine patients were included among which 154 suffering from septic shock were analysed. Presumed origin of septic shock was mainly pulmonary (36%), digestive (33%) and urinary (16%). 30 day-mortality reached 33%. Logistic regression after propensity score matching found a significant association between the 30-day mortality in the modified prehospital CCI ≥ 5: aOR = 1.12 [1.07-1.31], p = 0.041.

Among septic shock patients initially cared for by a MICU in the prehospital setting, a significant association between 30-day mortality. A modified prehospital CCI of at least 6 appears to be useful for early identification of septic shock patients with poorer outcome.