Utility of reverse shock index as a trauma triage tool among adult patients: concurrent use of Korean Triage and Acuity Scale

ABSTRACT

OBJECTIVE: The shock index (SI), as a trauma triage tool, is a capable clinical indicator of hemodynamic instability and hypovolemic shock, but the conception of SI is contradictory to shock. The reverse shock index (RSI) was introduced recently, but its utility has not been sufficiently proven. METHODS: This study examined the RSI utility by evaluating the procedures performed at an emergency department (ED) and the associated outcomes when the RSI is used alone or in combination with the Korean Triage and Acuity Scale (KTAS). This was a retrospective study conducted by including data of 4,789 adult trauma patients for a year. The clinical variables, procedures performed on patients, and outcomes were investigated. The median RSI was 0.9 in the RSI < 1 group. RESULTS: Patients in the RSI < 1 group had a higher odds of requiring procedures at the ED and for experiencing worse outcomes: intubation (odds ratio [OR], 5.4; 95% confidence interval [CI], 2.3–13.1; P < 0.001), chest tube insertion (OR, 6.5; 95% CI, 0.4–111.84; P < 0.001), use of emergency drugs (OR, 3.6; 95% CI, 1.5–8.5; P < 0.001), circulatory support (OR, 5.4; 95% CI, 2.3–12.9; P < 0.001), intensive care unit admission (OR, 3.5; 95% CI, 1.8–6.8; P < 0.001), and mortality during the ED stay (OR, 20.4; 95% CI, 5.5–75.7; P < 0.001). In the group with KTAS 1–3, trends similar to those in the RSI < 1 group were observed. Patients with RSI < 1 had more severe injuries and poorer outcomes than those with RSI≥1, regardless of whether the RSI was used alone or in combination with KTAS. CONCLUSION: RSI can provide an appropriate triage with concurrent KTAS use.