Characterization of Pediatric Traumatic Diaphragm Injury

Traumatic diaphragm injury (TDI) is a rare diagnosis occurring in less than 1 per cent of all pediatric traumas with several studies showing its association with injury severity and increased mortality. In addition, the consequence of diagnostic delay results in poorer outcomes secondary to herniation of abdominal contents, strangulation of intestine, sepsis, and even death. High index of suspicion and recognition of subtle clinical signs remain paramount for timely diagnosis. For children, there are little data available regarding this injury outside of small, single institutional case series and reports. We sought to characterize pediatric TDI with respect to associated injury patterns, injury severity, and outcomes to improve awareness of clinical situations where diagnosis is likely. Data for this analysis were derived from the National Trauma Data Bank Research Data Set from 2012 to 2014. The pediatric population was defined by ages 1 to 17. Pediatric trauma encounters over the given time frame totaled 335,469. Within this population, TDI was queried via ICD 9 coding for TDI (862.0 and 862.1). Specific data compiled for analysis included demographics, sex, Glasgow Coma Score (GCS), Injury Severity Score (ISS), outcomes, and associated injuries. Of the sample population, 620 children (0.18%) were diagnosed with TDI. Average age was 14 years and majority (81%) were male. TDI was associated with a lower GCS, higher ISS, and longer hospital/ intensive care unit (ICU) length of stay as compared with the overall pediatric population. Majority of injuries (69%) were secondary to penetrating mechanisms, although blunt injuries were associated with a statistically higher mortality, higher ISS, lower GCS, and longer hospital/ICU stay (Table 1). Overall mortality in the pediatric trauma cohort was 1.57 per cent whereas mortality associated with TDI was 24 per cent. TDI-associated injuries showed a predisposition toward several organ systems: hepatic, splenic, pulmonary, cardiac, rib fracture, vascular, renal, colon, and gastrointestinal. TDI had significantly higher overall rates of injuries in all queried organ systems. Blunt TDI was statistically more likely to be associated with splenic, pulmonary, renal, and thoracic musculoskeletal injuries whereas penetrating TDI was more likely to be associated with stomach injuries (Table 2). Our study represents the largest multicenter, multiyear cohort of pediatric diaphragm injuries ever described, mitigating some of the deficits of single-center, small sample studies. Our research establishes that TDI remains a rare diagnosis in the pediatric population with significant consequences on mortality and outcomes. We further establish the role of mechanism and associated injury patterns in the diagnosis of TDI in pediatrics. Given the lack of research surrounding TDI in the pediatric population, much of the data to date are garnered from the adult population with few data available in the pediatric literature. Research has consistently shown the correlation of TDI with specific injury patterns and mortality. Previously reported incidences of associated injuries were between 69 and 100 per cent with mortality rates ranging from 0 to 33 per cent.13 One specific study by Fair et al.4 evaluated traumatic diaphragm injuries in the adult population using the National Trauma Data Bank database. In this study, outcomes show similar trends between the adult and pediatric populations, but further evaluation of pediatric subpopulations revealed an overall increased mortality versus adults in both blunt (33 vs 20%) and penetrating (20 vs 9%) mechanisms. This is in addition to the relatively similar ISSs and decreased hospital Presented at the Pediatric Trauma Society 3rd Annual Meeting, November 11–12, 2016, Nashville, TN. Address correspondence and reprint requests to Michael C. Johnson, M.D., Division of Trauma and Emergency Surgery, Department of Surgery, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive (MC 7740), San Antonio, TX 78229-3900. E-mail: johnsonm9@uthscsa.edu.