Mortality is Reduced for Heart Rate 80 to 89 After Traumatic Brain Injury1

BackgroundIncreasing data indicate treatment with β blockers might improve survival after traumatic brain injury (TBI); the optimal heart rate (HR) range for these patients is unknown. To guide treatment, admission HR in moderate to severe TBI patients was analyzed to determine if a specific range is associated with decreased mortality.MethodsThe Los Angeles County Trauma System Database, consisting of five Level I and 8 Level II trauma centers, was queried for all injured patients admitted between 1998 and 2005 (n = 147,788). Isolated moderate to severe TBI patients (head abbreviated injury score ≥ 3) were then identified. Demographics and outcomes were compared at various admission HR subgroups (<50, 50–59, 60–69, 70–79, 80–89, 90–99, 100–109, ≥110). Logistic regression was then performed to determine predictors of mortality.ResultsAfter exclusions, a total of 11,977 isolated moderate to severe isolated TBI patients were analyzed, overall mortality was 11.5% with a trend toward lowest mortality at HR 80 to 89 (7.3%). Each HR subgroup had a significantly increased unadjusted odds ratio for mortality compared with HR 80 to 89, except HR 90 to 99 (OR 1.2, CI 1.0–1.5) and HR 100 to 109 (OR 1.2, CI 1.0–1.5). In multivariable logistic regression analysis, HR <50, 50–59, 60–69, and ≥110 were independent predictors for increased mortality compared with HR 80–89.ConclusionAfter isolated moderate to severe TBI, HR <50, 50–59, 60–69, and ≥110 were independent predictors of increased mortality. HR outside the range 70–109 could serve as a marker for aggressive resuscitation. As mortality increased significantly with HR: <50 (AOR 4.70), 50–59 (AOR 2.21), and 60–69 (AOR 1.63), our findings recommend avoiding HR < 70 in patients with moderate to severe TBI.