11.14 Tachycardia Is As Bad As Bradycardia In Traumatic Brain Injury

Posted on January 25, 2017

A. Azim1, P. Rhee2, K. Ibraheem1, T. O’Keeffe1, N. Kulvatunyou1, G. Vercruysse1, A. Tang1, L. Gries1, B. Joseph1  1University Of Arizona,Trauma And Surgical Critical Care/Department Of Surgery,Tucson, AZ, USA 2Grady Memorial Hospital,Trauma And Surgical Critical Care/Department Of Surgery,Atlanta, GA, USA

Introduction:
Heart rate (HR) at initial presentation is an important indicator of hemodynamic status of the patient. However, systolic blood pressure (SBP) often takes precedence over heart rate in clinical decision-making. The aim of this study was to assess the independent effect of admission HR on mortality in traumatic brain injury (TBI) patients. 

Methods:
A one-year (2011) analysis of the National Trauma Data Bank (NTDB) was performed. Patients with TBI (head abbreviated injury scale (AIS) score ≥3) were included. Transferred patients, patients dead on arrival, and those missing vitals on presentation were excluded. Patients were stratified into groups based on admission HR. Outcome of mortality was compared for different HR groups in reference to HR range of 90-100. The association of HR groups with mortality was assessed using multivariate regression analysis after controlling for age, head AIS, gender, ISS, vital parameters, admission GCS.

Results:
A total of 48,359 patients with isolated TBI were included with mean age 41 ± 37 years, median [Range] GCS score of 15 [3-15], mean (SD) SBP of 132 (40) mm of Hg, and mean HR of 88 ± 29 bpm. The overall mortality rate was 8.9% (n=4,321). Patients with HR >100 were 25% more likely to die compared to patients with HR between 90-100 (OR: [95% CI]: 1.253 [1.117-1.404], p<0.001).  Mortality in patients with heart rate <90 was 23% higher than patients with HR between 90-100 (OR: [95% CI]: 1.23 [1.103-1.371], p<0.001). Patients with HR in the range of 80-90 bpm had the lowest mortality rate among the groups (p<0.001). With every 10 bpm increase or decrease from HR range of 90-100, mortality increases.

Conclusion:
Admission heart rate is independently associated with mortality in TBI patients regardless of their presenting SBP and GCS. The results of our study demonstrate a curvilinear association towards both extremes of heart rate. Patients who are either tachycardic or bradycardic have an associated increased mortality and warrant careful evaluation.