Deadly Duo for EMS in TBI

Short Attention Span Summary

Brains like BP and O2
We know prehospital hypotension and hypoxia are bad for patients with traumatic brain injury.  But what if a patient has both?  Comparing patients over age 10 with moderate or severe traumatic brain injury with neither hypoxia nor hypotension, hypotension alone, hypoxia alone, or both, mortality was: 5.6%, 20.7%, 28.1%, and 43.9%, respectively.  Efforts to establish and reinforce EMS protocols and education to aggressively prevent hypotension and hypoxia in head injured patients will save lives.

Spoon Feed
Hypotension or hypoxia increase mortality in head-injured patients, and both together are even worse.  This is a tangible opportunity for EMS pros to make a big impact and save lives.


Abstract

Ann Emerg Med. 2017 Jan;69(1):62-72. doi: 10.1016/j.annemergmed.2016.08.007. Epub 2016 Sep 28.

The Effect of Combined Out-of-Hospital Hypotension and Hypoxia on Mortality in Major Traumatic Brain Injury.

Spaite DW1, Hu C2, Bobrow BJ3, Chikani V4, Barnhart B5, Gaither JB6, Denninghoff KR6, Adelson PD7, Keim SM6, Viscusi C6, Mullins T8, Sherrill D9.

Author information:

1Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ; Department of Emergency Medicine, College of Medicine, the University of Arizona, Tucson, AZ. Electronic address: dan@aemrc.arizona.edu.

2Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ; College of Public Health, the University of Arizona, Tucson, AZ.

3Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ; Department of Emergency Medicine, College of Medicine, the University of Arizona, Tucson, AZ; Arizona Department of Health Services, Bureau of EMS and Trauma System, Phoenix, AZ.

4Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ; Arizona Department of Health Services, Bureau of EMS and Trauma System, Phoenix, AZ.

5Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ.

6Arizona Emergency Medicine Research Center, College of Medicine, the University of Arizona, Phoenix, AZ; Department of Emergency Medicine, College of Medicine, the University of Arizona, Tucson, AZ.

7Barrow Neurological Institute at Phoenix Children's Hospital and Department of Child Health/Neurosurgery, College of Medicine, the University of Arizona, Phoenix, AZ.

8Arizona Department of Health Services, Bureau of EMS and Trauma System, Phoenix, AZ.

9College of Public Health, the University of Arizona, Tucson, AZ.

Abstract

STUDY OBJECTIVE:

Survival is significantly reduced by either hypotension or hypoxia during the out-of-hospital management of major traumatic brain injury. However, only a handful of small studies have investigated the influence of the combination of both hypotension and hypoxia occurring together. In patients with major traumatic brain injury, we evaluate the associations between mortality and out-of-hospital hypotension and hypoxia separately and in combination.

METHODS:

All moderate or severe traumatic brain injury cases in the preimplementation cohort of the Excellence in Prehospital Injury Care study (a statewide, before/after, controlled study of the effect of implementing the out-of-hospital traumatic brain injury treatment guidelines) from January 1, 2007, to March 31, 2014, were evaluated (exclusions: <10 years, out-of-hospital oxygen saturation ≤10%, and out-of-hospital systolic blood pressure <40 or >200 mm Hg). The relationship between mortality and hypotension (systolic blood pressure <90 mm Hg) or hypoxia (saturation <90%) was assessed with multivariable logistic regression, controlling for Injury Severity Score, head region severity, injury type (blunt versus penetrating), age, sex, race, ethnicity, payer, interhospital transfer, and trauma center.

RESULTS:

Among the 13,151 patients who met inclusion criteria (median age 45 years; 68.6% men), 11,545 (87.8%) had neither hypotension nor hypoxia, 604 (4.6%) had hypotension only, 790 (6.0%) had hypoxia only, and 212 (1.6%) had both hypotension and hypoxia. Mortality for the 4 study cohorts was 5.6%, 20.7%, 28.1%, and 43.9%, respectively. The crude and adjusted odds ratios for death within the cohorts, using the patients with neither hypotension nor hypoxia as the reference, were 4.4 and 2.5, 6.6 and 3.0, and 13.2 and 6.1, respectively. Evaluation for an interaction between hypotension and hypoxia revealed that the effects were additive on the log odds of death.

CONCLUSION:

In this statewide analysis of major traumatic brain injury, combined out-of-hospital hypotension and hypoxia were associated with significantly increased mortality. This effect on survival persisted even after controlling for multiple potential confounders. In fact, the adjusted odds of death for patients with both hypotension and hypoxia were more than 2 times greater than for those with either hypotension or hypoxia alone. These findings seem supportive of the emphasis on aggressive prevention and treatment of hypotension and hypoxia reflected in the current emergency medical services traumatic brain injury treatment guidelines but clearly reveal the need for further study to determine their influence on outcome.

Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

PMCID: PMC5173421 [Available on 2018-01-01]

PMID: 27692683 [PubMed - in process]