Admission heart rate is a predictor of mortality

The association between admission heart rate (AHR) and mortality after trauma can assist initial emergency department triage and resuscitation. In addition, increased AHR is often associated with sympathetic hyperactivity which may require targeted treatment. We determined whether AHR was a predictor for mortality in trauma patients.

The Los Angeles County Trauma System Database was queried for all injured patients admitted between 1998 and 2005 (n = 147,788). Traumatic brain injury (TBI) patients (head Abbreviated Injury Scale score ≥ 3) were excluded. Demographics were compared at various AHR subgroups (<50, 50-59, 60-69, 70-79, 80-89, 90-99, 100-109, and ≥ 110). Mortality was compared at various AHR ranges, and logistic regression was performed to determine significance.

After exclusions, 103,799 trauma patients requiring admission were identified; overall mortality was 1.4%. AHR 80 to 89 demonstrated a statistically significant lower mortality (0.5%) compared with all other AHR ranges, except AHR 70 to 79 (0.6%). In trauma patients who required admission, AHR 70 to 79 and 80 to 89 were predictors of lower mortality. Mortality for 22,232 moderate to severely injured patients was 5.5% and AHR 80 to 89 demonstrated a statistically lower mortality (2.0%) than all other AHR ranges, except AHR 70 to 79 (1.9%). After moderate to severe trauma, AHR <60 and ≥ 100 were associated with significantly higher mortality.

Mortality after trauma increases outside the AHR range of 70 to 89 beats per minute. AHR ranges previously considered "normal" were associated with significantly increased mortality. Prospective research is required to evaluate if resuscitation goals should target heart rate at the 70 to 89 range.