Blast Injury in a Civilian Trauma Setting is Associated with a Delay in Diagnosis of Traumatic Brain Injury

Abstract

High-pressure waves (blast) account for the majority of combat injuries and are becoming increasingly common in terrorist attacks. To our knowledge, there are no data evaluating the epidemiology of blast injury in a domestic nonterrorist setting. Data were analyzed retrospectively on patients admitted with any type of blast injury over a 10-year period at a busy urban trauma center. Injuries were classified by etiology of explosion and anatomical location. Eighty-nine cases of blast injury were identified in 57,392 patients (0.2%) treated over the study period. The majority of patients were male (78%) with a mean age of 40 ± 17 years. The mean Injury Severity Score was 13 ± 11 with an admission Trauma and Injury Severity Score of 0.9 ± 0.2 and Revised Trauma Score of 7.5 ± 0.8. The mean intensive care unit and hospital length of stay was 2 ± 7 days and 4.6 ± 10 days, respectively, with an overall mortality rate of 4.5 per cent. Private dwelling explosion [n = 31 (35%)] was the most common etiology followed by industrial pressure blast [n = 20 (22%)], industrial gas explosion [n = 16 (18%)], military training-related explosion [n = 15 (17%)], home explosive device [n = 8 (9%)], and fireworks explosion [n = 1 (1%)]. Maxillofacial injuries were the most common injury (n = 78) followed by upper extremity orthopedic (n = 29), head injury (n = 32), abdominal (n = 30), lower extremity orthopedic (n = 29), and thoracic (n = 19). The majority of patients with head injury [28 of 32 (88%)] presented with a Glasgow Coma Scale score of 15. CT scans on admission were initially positive for brain injury in 14 of 28 patients (50%). Seven patients (25%) who did not have a CT scan on admission had a CT performed later in their hospital course as a result of mental status change and were positive for traumatic brain injury (TBI). Three patients (11%) had a negative admission CT with a subsequently positive CT for TBI over the next 48 hours. The remaining four patients (14%) were diagnosed with skull fractures. All patients (n = 4) with an admission Glasgow Coma Scale score of less than 8 died from diffuse axonal injury. Blast injury is a complicated disease process, which may evolve over time, particularly with TBI. The missed injury rate for TBI in patients with a Glasgow Coma Scale score of 15 was 36 per cent. More studies are needed in the area of blast injury to better understand this disease process.