Thomas Velky

The impact of prehospital endotracheal intubation on outcome in moderate to severe traumatic brain injury.

BACKGROUND Although early intubation to prevent the mortality that accompanies hypoxia is considered the standard of care for severe traumatic brain injury (TBI), the efficacy of this approach remains unproven. METHODS Patients with moderate to severe TBI (Head/Neck Abbreviated Injury Scale [AIS] score 3+) were identified from our county trauma registry. Logistic regression was used to explore the impact of prehospital intubation on outcome, controlling for age, gender, mechanism, Glasgow Coma Scale score, Head/Neck AIS score, Injury Severity Score, and hypotension. Neural network analysis was performed to identify patients predicted to benefit from prehospital intubation. RESULTS A total of 13,625 patients from five trauma centers were included; overall mortality was 22.9%, and 19.3% underwent prehospital intubation. Logistic regression revealed an increase in mortality with prehospital intubation (odds ratio, 0.36; 95% confidence interval, 0.32-0.42; p < 0.001). This was true for all patients, for those with severe TBI (Head/Neck AIS score 4+ and/or Glasgow Coma Scale score of 3-8), and with exclusion of patients transported by aeromedical crews. Patients intubated in the field versus the emergency department had worse outcomes. Neural network analysis identified a subgroup of patients with more significant injuries as potentially benefiting from prehospital intubation. CONCLUSION Prehospital intubation is associated with a decrease in survival among patients with moderate-to-severe TBI. More critically injured patients may benefit from prehospital intubation but may be difficult to identify prospectively.

Early ventilation and outcome in patients with moderate to severe traumatic brain injury.

Objectives:An increase in mortality has been reported with early intubation in severe traumatic brain injury, possibly due to suboptimal ventilation. This analysis explores the impact of early ventilation on outcome in moderate to severe traumatic brain injury. Design:Retrospective, registry-based analysis. Setting:This study was conducted in a large county trauma system that includes urban, suburban, and rural jurisdictions. Patients:Nonarrest trauma victims with a Head Abbreviated Injury Score of ≥3 were identified from our county trauma registry. Interventions:Intubated patients were stratified into 5 mm Hg arrival Pco2 increments. Logistic regression was used to calculate odds ratios for each increment, adjusting for age, gender, mechanism of injury, year of injury, preadmission Glasgow Coma Scale score, hypotension, Head Abbreviated Injury Score, Injury Severity Score, Po2, and base deficit. Increments with the highest relative survival were used to define the optimal Pco2 range. Outcomes for patients with arrival Pco2 values inside and outside this optimal range were then explored for both intubated and nonintubated patients, adjusting for the same factors as defined previously. In addition, the independent outcome effect of hyperventilation and hypoventilation was assessed. Measurements and Main Results:A total of 890 intubated and 2,914 nonintubated patients were included. Improved survival was observed for the arrival Pco2 range 30–49 mm Hg. Patients with arrival Pco2 values inside this optimal range had improved survival and a higher incidence of good outcomes. Conversely, there was no improvement in outcomes for patients within this optimal Pco2 range for nonintubated patients after adjusting for all of the factors defined previously. Both hyperventilation and hypoventilation were associated with worse outcomes in intubated but not nonintubated patients. The proportion of arrival Pco2 values within the optimal range was lower for intubated vs. nonintubated patients. Conclusions:Arrival hypercapnia and hypocapnia are common and associated with worse outcomes in intubated but not spontaneously breathing patients with traumatic brain injury.

The influence of vehicle damage on injury severity of drivers in head-on motor vehicle crashes

Data from crashes investigated through the Crash Injury Research and Engineering Network (CIREN) Program were used to assess differences in injury patterns, severity, and sources for drivers, protected by safety belts and deploying steering wheel air bags, in head-on frontal impacts. We studied whether exterior vehicle damage with a different distribution (wide vs. narrow) across the front vehicle plane influenced injury characteristics. Drivers from both impact types were similar on the basis of demographic characteristics (except age), restraint use, and vehicle characteristics. There were significant differences in the type of object contacted and intrusion into the passenger compartment at the drivers seat location. The mean delta V (based on the kilometers per hour change in velocity during the impact) was similar for drivers in both (wide vs. narrow) impact types. There were no significant differences in injury patterns and sources except that drivers in wide impacts were almost 4 times more likely (odds ratio (OR)=3.81, 95% confidence limits (CL) 1.26, 11.5) to have an abbreviated injury scale (AIS) 3 serious or greater severity head injury. Adjusted odds ratios showed that drivers in wide impacts were less likely (OR=0.54, 95% CI 0.37, 0.79) to have severe injury (based on injury severity score (ISS)>25) when controlling for intrusion, vehicle body type, vehicle curb weight, age, proper safety belt use, and delta V. Drivers with intrusion into their position or who were driving a passenger vehicle were almost twice more likely to have severe injury, regardless of whether the frontal plane damage distribution was wide or narrow. Our study supports that the type of damage distribution across the frontal plane may be an important crash characteristic to consider when studying drivers injured in head-on motor vehicle crashes.