Age shock index, shock index, and modified shock index for predicting postintubation hypotension in the emergency department



      Hypotension after emergent ETI is a relatively common complication during and after emergency airway management. We aimed to evaluate SI, MSI, and age SI to predict PIH in patients who presented to the emergency department. Moreover, which factors would be better for predicting the event or similar to the others.


      A retrospective, standardized chart review of consecutive ED patients requiring intubation at an urban, tertiary-care teaching hospital, from January 2011 to December 2016. PIH was defined as any recorded SBP <90 mmHg or MAP <65 mmHg within the 60-minute period after intubation.


      Hypotension after emergent ETI was observed in 130 (29.7%) patients. The ROC-AUC of age SI, MSI, and SI before intubation for prediction of PIH were 0.676 (95% CI 0.63–0.72), 0.614 (95% CI 0.567–0.66), and 0.611 (95% CI 0.564–0.657). The prognostic performance of age SI for prediction of PIH was better than MSI and SI (p = 0.006 for age SI versus MSI, p = 0.005 for age SI versus SI).


      Preintubation age SI, MSI, and SI are all independent predictors of PIH in patients who need emergent intubation. Aong these parameters, age SI is the best marker to predict the outcome. Calculation of these indexes are simple and could be an guide of implement to prevent hypotension after ETI.
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