Diaphragmatic injuries: why are they overlooked?

Twenty-one cases of diaphragmatic tears (11 blunt and ten penetrating injuries) were reviewed retrospectively. Left-sided diaphragmatic ruptures predominated except for two patients with penetrating injuries and one patient with bilateral tears following blunt trauma. Significant associated injuries (injury severity score greater than 16) were present in 76% of cases: the most common being intra-abdominal visceral injuries of the stomach, spleen and liver. Initial hypotension (systolic pressure less than 100 mmHg) was present in seven patients and respiratory distress (rate greater than 30 per min and/or Pa,O2 less than 70 mmHg) was seen in eight cases. Correct preoperative diagnosis was made in six cases while 12 were only detected during operation. The other three cases were diagnosed late. A variety of reasons accounts for the tendency to overlook diaphragmatic injuries in trauma victims. First, it is an uncommon condition presenting to an unsuspecting clinician. Second, the paucity of pathognomonic clinical signs makes for a difficult diagnosis. Third, the diverting attention of life-threatening visceral injuries accounts for failure to identify patients with the few available clinical and radiological features.