Identification of major hemorrhage in trauma patients in the prehospital setting: diagnostic accuracy and impact on outcome

Jared M Wohlgemut; Erhan Pisirir; Rebecca S Stoner; Evangelia Kyrimi; Michael Christian; Thomas Hurst; William Marsh; Zane B Perkins; Nigel R M Tai

doi:10.1136/tsaco-2023-001214

Identification of major hemorrhage in trauma patients in the prehospital setting: diagnostic accuracy and impact on outcome

Trauma Surg Acute Care Open. 2024 Jan 12;9(1):e001214. doi: 10.1136/tsaco-2023-001214. eCollection 2024.

Authors

Jared M Wohlgemut^{1

2}, Erhan Pisirir³, Rebecca S Stoner^{1

2}, Evangelia Kyrimi³, Michael Christian⁴, Thomas Hurst⁴, William Marsh³, Zane B Perkins^{1

2}, Nigel R M Tai^{1

2}

Affiliations

¹ Centre for Trauma Sciences, Blizard Institute, Queen Mary University of London, London, UK.
² Trauma Service, Royal London Hospital, Barts Health NHS Trust, London, UK.
³ School of Electronic Engineering and Computer Science, Queen Mary University of London, London, UK.
⁴ London's Air Ambulance, London, UK.

Abstract

Background: Hemorrhage is the most common cause of potentially preventable death after injury. Early identification of patients with major hemorrhage (MH) is important as treatments are time-critical. However, diagnosis can be difficult, even for expert clinicians. This study aimed to determine how accurate clinicians are at identifying patients with MH in the prehospital setting. A second aim was to analyze factors associated with missed and overdiagnosis of MH, and the impact on mortality.

Methods: Retrospective evaluation of consecutive adult (≥16 years) patients injured in 2019-2020, assessed by expert trauma clinicians in a mature prehospital trauma system, and admitted to a major trauma center (MTC). Clinicians decided to activate the major hemorrhage protocol (MHPA) or not. This decision was compared with whether patients had MH in hospital, defined as the critical admission threshold (CAT+): administration of ≥3 U of red blood cells during any 60-minute period within 24 hours of injury. Multivariate logistical regression analyses were used to analyze factors associated with diagnostic accuracy and mortality.

Results: Of the 947 patients included in this study, 138 (14.6%) had MH. MH was correctly diagnosed in 97 of 138 patients (sensitivity 70%) and correctly excluded in 764 of 809 patients (specificity 94%). Factors associated with missed diagnosis were penetrating mechanism (OR 2.4, 95% CI 1.2 to 4.7) and major abdominal injury (OR 4.0; 95% CI 1.7 to 8.7). Factors associated with overdiagnosis were hypotension (OR 0.99; 95% CI 0.98 to 0.99), polytrauma (OR 1.3, 95% CI 1.1 to 1.6), and diagnostic uncertainty (OR 3.7, 95% CI 1.8 to 7.3). When MH was missed in the prehospital setting, the risk of mortality increased threefold, despite being admitted to an MTC.

Conclusion: Clinical assessment has only a moderate ability to identify MH in the prehospital setting. A missed diagnosis of MH increased the odds of mortality threefold. Understanding the limitations of clinical assessment and developing solutions to aid identification of MH are warranted.

Level of evidence: Level III-Retrospective study with up to two negative criteria.

Study type: Original research; diagnostic accuracy study.

Keywords: diagnosis; diagnostic accuracy; hemorrhage; multiple trauma.