Traumatic diaphragmatic injury in the American College of Surgeons National Trauma Data Bank: a new examination of a rare diagnosis.

Background: Traumatic diaphragmatic injury (TDI) is a rarely diagnosed injury in trauma. Previous studies have been limited in their evaluation of TDI because of small population size and center bias. Although injuries may be suspected based on penetrating mechanism, blunt injuries may be particularly difficult to detect. The American College of Surgeons National Trauma Data Bank is the largest trauma database in the United States. We hypothesized that we could identify specific injury patterns associated with blunt and penetrating TDIs.

Methods: We examined demographics, diagnoses, mechanism of injury, and outcomes for patients with TDI in 2012 as this is the largest and most recent dataset available. Comparisons were made using chi-square or independent samples t test.

Results: There were a total of 833,309 encounters in the National Trauma Data Bank in 2012. Three thousand eight hundred seventy-three patients had a TDI (.46%). Of those, 1,240 (33%) patients had a blunt mechanism and 2,543 (67%) had a penetrating mechanism. Patients with blunt TDI were older (44 ± 19 vs 31 ± 13 years, P < .001), had a higher injury severity score (33 ± 14 vs 24 ± 15, P < .001), and a higher mortality rate (19.8% vs 8.8%, P < .001). Compared with patients with penetrating injuries, those with blunt TDI were more likely to have injuries to the thoracic aorta (2.9% vs .5%, P < .001), lung (48.7% vs 28.1, P < .001), bladder (5.9% vs .7%, P < .001), and spleen (44.8% vs 29.1%, P < .001). Penetrating TDI was associated with liver and hollow viscus injuries.

Conclusions: Diaphragmatic injury is an uncommon but significant diagnosis in trauma patients. Blunt injuries may be more likely to be occult; however, a pattern of associated injuries to the aorta, lung, spleen, and bladder should prompt further workup for TDI.