PITFALLS IN THE DIAGNOSIS OF BLUNT DIAPHRAGMATIC INJURY

BACKGROUND: Severe blunt trauma to the torso result in diaphragmatic d isruption. Prompt recognition of this potentially life-threatening inj ury is difficult when the initial chest roentgenogram is unrevealing a nd immediate thoracotomy or celiotomy is not performed. This retrospec tive study was undertaken to: (1) determine the incidence of missed di aphragmatic injuries on initial evaluation; (2) identify factors contr ibuting to diagnostic delays; and (3) formulate a diagnostic approach that reliably detects diaphragmatic rupture following blunt trauma. ME THODS: Retrospective review of hospital records and radiographs from o ur 18-year experience with blunt diaphragmatic injuries. RESULTS: Seve n of 57 (12%) blunt diaphragmatic injuries were missed on initial eval uation. Recognition followed 2 days to 3 months later. Two (4%) isolat ed left-sided injuries initially presented with normal chest roentgeno grams. Five patients (9%) (4 with right-sided ruptures) had abnormalit ies on chest roentgenogram or computed tomography (CT) initially attri buted to chest trauma. They were diagnosed by radionuclide, ultrasound , or CT investigations of hemothorax, pulmonary sepsis, and right uppe r quadrant pain; and, in 1 case, at thoracotomy for a persistent right hemothorax. In the remaining 50 patients (88%), the diagnosis was est ablished within 24 hours. In 21 (42%) of these, the problem was initia lly recognized at the time of celiotomy for accompanying injuries. CON CLUSIONS: Blunt diaphragmatic injuries are easily missed in the absenc e of other indications for immediate surgery, since radiologic abnorma lities of the diaphragm-particularly those involving the right hemidia phragm-are often interpreted as thoracic trauma. In this setting, a hi gh index of suspicion coupled with selective use of radionuclide scann ing, ultrasound, and CT or magnetic resonance imaging is necessary for early detection of this uncommon injury.