Associated injuries in blunt solid organ trauma: implications for missed injury in nonoperative management.

BACKGROUND: During the past decade, nonoperative management (NOM) of hemodynamically stable blunt trauma patients with liver (L) or spleen (S) injury has become the standard of care. This trend has led to concerns over missed associated intra-abdominal injuries with concomitant morbidity. To better understand the incidence and risk of missed injury, patterns of associated intra-abdominal injury were examined in all patients with blunt liver and spleen injuries, and missed injuries were reviewed in patients undergoing NOM.
METHODS: Patients were identified from the registry of a Level I trauma center over a 3-year period. Records were reviewed for demographics, injury characteristics, and associated injuries. Indications for primary operation were hemodynamic instability or significant associated intra-abdominal injury. Missed injury was defined as unsuspected intra-abdominal injury requiring laparotomy in patients otherwise undergoing NOM for liver or spleen injury.
RESULTS: Eight hundred three patients (338 in the L group, 345 in the S group, and 120 in the L + S group) were treated between December 1995 and December 1998. Rates of planned NOM were 89% (L group), 78% (S group), and 75% (L + S group). On examination of all patients with blunt liver or spleen injuries, the incidence of associated intra-abdominal injury was higher in the L group at 5% as compared with 1.7% in the S group (p = 0.02). The associated intra-abdominal injury rate in the L + S group was similar to the L group at 4.2%. Although in the L and S groups, rates of diaphragm (0.5% vs. 1%, p = 0.45) and intra-abdominal bladder injury (0.3% vs. 0.3%, p = 0.99) were similar, bowel injury was more common in the L group (11% vs. 0%, p = 0.0004), as was pancreatic injury (7% vs. 0%, p = 0.007). In NOM patients, missed injury occurred in seven (2.3%) L patients versus zero S patients (p = 0.012). No L + S patient had unexpected injuries. Missed injuries included two small bowel, three diaphragm, one pancreas, and one mesenteric tear.
CONCLUSION: Damage to the pancreas and bowel is significantly associated with liver as opposed to spleen injuries. Actual missed intra-abdominal injury with NOM mirrors this pattern, occurring more often with liver than with spleen injuries. However, the overall incidence of missed injury is quite low, and should not influence decisions concerning eligibility for NOM. We speculate that the greater amount and/or different vector of energy transfer needed to injure the liver versus the spleen accounts for the greater rate of associated injuries to the pancreas/small bowel.