Shock Index as a Predictor of Mortality in Intubated Patients in a Tertiary Care Hospital
DOI:
https://doi.org/10.54112/bcsrj.v6i2.2373Keywords:
Shock index; endotracheal intubation; mortality; hemodynamic instability; critical illnessAbstract
Emergency endotracheal intubation in critically ill patients is frequently complicated by hemodynamic instability and mortality. The shock index, calculated as heart rate divided by systolic blood pressure, may provide a rapid bedside method for identifying high-risk patients before intubation. Objective: To determine the prognostic value of the pre-intubation shock index for in-hospital mortality among adults undergoing emergency endotracheal intubation in a tertiary-care hospital. Methods: This prospective observational cohort study included 80 consecutively enrolled adult patients who underwent emergency endotracheal intubation between June and November 2024. Pre-intubation clinical and hemodynamic variables were recorded, and the shock index was calculated. A shock index of ≥0.90 was considered elevated. The primary outcome was all-cause in-hospital mortality. Receiver operating characteristic curve analysis and multivariable binary logistic regression were performed to assess predictive performance and independent associations with mortality. Results: The mean age of the patients was 51.6 ± 16.2 years, and 50 (62.5%) were male. The mean pre-intubation shock index was 0.93 ± 0.24, while 35 (43.8%) patients had a shock index of ≥0.90. Overall, in-hospital mortality was 31.3% (25/80). The mean shock index was significantly higher among non-survivors than survivors (1.10 ± 0.25 versus 0.85 ± 0.19; p<0.001). Mortality was 51.4% in patients with a shock index of ≥0.90 compared with 15.6% in those with a lower shock index (risk ratio 3.31; 95% CI: 1.56–7.02). After adjustment for SOFA score and serum lactate, a shock index of ≥0.90 remained independently associated with mortality (adjusted OR 4.08; 95% CI: 1.32–12.60; p=0.015). The area under the receiver operating characteristic curve was 0.79, with 72.0% sensitivity, 69.1% specificity, and an 84.4% negative predictive value at the ≥0.90 threshold. Conclusion: A pre-intubation shock index of ≥0.90 was independently associated with increased in-hospital mortality and peri-intubation complications. It may serve as a simple and readily available bedside tool for early risk stratification before emergency intubation.
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Copyright (c) 2025 Anisa Malik, Mariam Barkat, Amna Tariq, Ayesha Akram, Syeda Sobya Owais, Marium Farid
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