RELATIONSHIP BETWEEN SHOCK INDEX, MODIFIED SHOCK INDEX, AND AGE SHOCK INDEX AND 28-DAY MORTALITY AMONG PATIENTS WITH PREHOSPITAL SEPTIC SHOCK

A relative hypovolemia occurs during septic shock (SS); the early phase is clinically reflected by tachycardia and low blood pressure. In the prehospital setting, simple objective tools to assess hypovolemia severity are needed to optimize triaging. The aim of this study was to evaluate the relationship between shock index (SI), diastolic SI (DSI), modified SI (MSI), and age SI (ASI) and 28-day mortality of patients with SS initially cared for in a prehospital setting of a mobile intensive care unit (MICU). From April 6, 2016 through December 31, 2021, 530 patients with SS cared for at a prehospital MICU were analyzed retrospectively. Initial SI, MSI, DSI, and ASI values, that is, first measurement after MICU arrival to the scene were calculated. A propensity score analysis with inverse probability of treatment weighting (IPTW) method was used to assess the relationship between SI, DSI, MSI, and ASI and 28-day mortality. SS resulted mainly from pulmonary, digestive, and urinary infections in 44%, 25%, and 17% of patients. The 28-day overall mortality was 31%. IPTW propensity score analysis indicated a significant relationship between 28-day mortality and SI (adjusted odds ratio [aOR] 1.13; 95% CI 1.01–1.26; p = 0.04), DSI (aOR 1.16; 95% CI 1.06–1.34; p = 0.03), MSI (aOR 1.03; 95% CI 1.01–1.17; p = 0.03), and ASI (aOR 3.62; 95% CI 2.63–5.38; p < 10–6). SI, DSI, MSI, and ASI were significantly associated with 28-day mortality among patients with SS cared for at a prehospital MICU. Further studies are needed to confirm the usefulness of SI and SI derivates for prehospital SS optimal triaging.