Discrepancy between heart rate and makers of hypoperfusion is a predictor of mortality in trauma patients

Tachycardia is an important early sign of shock in trauma. Although the base deficit (BD) and lactate are indicative of hypoperfusion and known to predict mortality, some cases show a discrepancy between heart rate (HR) and BD or lactate; such cases have poor prognosis. The objective of this study was to examine whether lack of tachycardia after hypoperfusion is associated with increased mortality.

Retrospective data were collected on 1,742 adult trauma patients. Mortality was compared with different levels of BD, lactate, and HR on admission. Multivariate logistic regression was used to identify significant risk factors for mortality.

Significantly increased mortality was observed in patients with hypoperfusion (BD less than -5 mmol/L or lactate more than 5 mmol/L). Among these patients, those with a normal HR (<80 bpm) were associated with a higher mortality rate than those with tachycardia (HR, 80-100 or>100 bpm). However, systolic blood pressure (SBP) was not significantly different between the different HR groups. Logistic regression analysis revealed that discrepancy between HR and indicators of hypoperfusion (Dis BD: BD less than -5 mmol/L and HR less than 80 bpm; or Dis lac: lactate more than 5 mmol/L and HR less than 80 bpm) are independent predictors of mortality after controlling for age, SBP, Injury Severity Score, head Abbreviated Injury Scale, HR, and BD or lactate (Dis BD: odds ratio, 2.67; 95% confidence interval, 1.07-6.61; p<0.05 and Dis lac: odds ratio, 4.11; 95% confidence interval, 1.57-10.74; p<0.01, respectively).

The lack of tachycardia in the presence of hypoperfusion is associated with poor prognosis independent of injury severity, SBP, and head injury. A discrepancy between HR and indicators of hypoperfusion could be considered as a predictor of mortality in trauma patients.