The effects of prehospital TXA on mortality and neurologic outcomes in patients with traumatic intracranial hemorrhage: a subgroup analysis from the prehospital TXA for TBI trial.

BACKGROUND: In the Prehospital Tranexamic Acid (TXA) for TBI Trial, TXA administered within two hours of injury in the out-of-hospital setting did not reduce mortality in all patients with moderate/severe traumatic brain injury (TBI). We examined the association between TXA dosing arms, neurologic outcome, and mortality in patients with intracranial hemorrhage (ICH) on computed tomography (CT). METHODS: This was a secondary analysis of the Prehospital Tranexamic Acid for TBI Trial (ClinicalTrials.gov [NCT01990768]) that randomized adults with moderate/severe TBI (Glasgow Coma Scale<13) and systolic blood pressure > =90 mmHg within two hours of injury to a 2-gram out-of-hospital TXA bolus followed by an in-hospital saline infusion, a 1-gram out-of-hospital TXA bolus/1-gram in-hospital TXA infusion, or an out-of-hospital saline bolus/in-hospital saline infusion (placebo). This analysis included the subgroup with ICH on initial CT. Primary outcomes included 28-day mortality, 6-month Glasgow Outcome Scale-Extended (GOSE) < = 4, and 6-month Disability Rating Scale (DRS). Outcomes were modeled using linear regression with robust standard errors. RESULTS: The primary trial included 966 patients. Among 541 participants with ICH, 28-day mortality was lower in the 2-gram TXA bolus group (17%) compared to the other two groups (1-gram bolus/1-gram infusion 26%, placebo 27%). The estimated adjusted difference between the 2-gram bolus and placebo groups was -8·5 percentage points (95% CI, -15.9 to -1.0) and between the 2-gram bolus and 1-gram bolus/1-gram infusion groups was -10.2 percentage points (95% CI, -17.6 to -2.9). DRS at 6 months was lower in the 2-gram TXA bolus group than the 1-gram bolus/1-gram infusion (estimated difference -2.1 [95% CI, -4.2 to -0.02]) and placebo groups (-2.2 [95% CI, -4.3, -0.2]). Six-month GOSE did not differ among groups. CONCLUSIONS: A 2-gram out-of-hospital TXA bolus in patients with moderate/severe TBI and ICH resulted in lower 28-day mortality and lower 6-month DRS than placebo and standard TXA dosing. LEVEL OF EVIDENCE: Therapeutic/Care Management, Level II.

Out-of-Hospital Research in the Era of Electronic Health Records.

Conducting out-of-hospital research is unique and challenging and requires tracking patients across multiple phases of care, using multiple sources of patient records and multiple hospitals. The logistics and strategies used for out-of-hospital research are distinct from other forms of clinical research. The increasing use of electronic health records (EHRs) by hospitals and emergency medical services (EMS) agencies presents a large opportunity for accelerating out-of-hospital research, as well as particular challenges. In this study, we describe seven key aspects of designing and implementing out-of-hospital research in the era of EHRs: (1) selection of research sites, (2) defining the patient population, (3) patient sampling and sample size calculations, (4) EMS data, (5) hospital selection, (6) handling missing data, and (7) statistical analysis. We use examples from a recent prospective out-of-hospital cohort study to illustrate these topics, including lessons learned.

Prospective Validation of the National Field Triage Guidelines for Identifying Seriously Injured Persons.

BACKGROUND: The national field trauma triage guidelines have been widely implemented in US trauma systems, but never prospectively validated. We sought to prospectively validate the guidelines, as applied by out-of-hospital providers, for identifying high-risk trauma patients. STUDY DESIGN: This was an out-of-hospital prospective cohort study from January 1, 2011 through December 31, 2011 with 44 Emergency Medical Services agencies in 7 counties in 2 states. We enrolled injured patients transported to 28 acute care hospitals, including 7 major trauma centers (Level I and II trauma hospitals) and 21 nontrauma hospitals. The primary exposure term was Emergency Medical Services' use of one or more field triage criteria in the national field triage guidelines. Outcomes included Injured Severity Score ≥16 (primary) and critical resource use within 24 hours of emergency department arrival (secondary). RESULTS: We enrolled 53,487 injured children and adults transported by Emergency Medical Services to an acute care hospital, 17,633 of which were sampled for the primary analysis; 13.9% met field triage guidelines, 3.1% had Injury Severity Score ≥16, and 1.7% required early critical resources. The sensitivity and specificity of the field triage guidelines were 66.2% (95% CI, 60.2-71.7%) and 87.8% (95% CI, 87.7-88.0%) for Injury Severity Score ≥16 and 80.1% (95% CI, 65.8-89.4%) and 87.3% (95% CI 87.1-87.4%) for early critical resource use. Triage guideline sensitivity decreased with age, from 87.4% in children to 51.8% in older adults. CONCLUSIONS: The national field triage guidelines are relatively insensitive for identifying seriously injured patients and patients requiring early critical interventions, particularly among older adults.