Blunt Intra-abdominal Injury

Make the Diagnosis: Blunt Intra-abdominal Injury

Prior Probability of Intra-abdominal Injury After Blunt Abdominal Trauma

Among emergency department patients who sustained blunt abdominal trauma, the probability of an intra-abdominal injury is 13% (95% CI, 10%-17%), and 4.7% (95% CI, 2.5%-8.6%) have an injury significant enough that therapeutic surgery or angiographic embolization is required.

Population in Whom an Abdominal Injury Should be Considered

Abdominal injuries can be caused by blunt trauma from direct blows or from rapid deceleration. All emergency patients who sustained trauma should have a rapid trauma-focused examination to identify and correct life-threatening conditions affecting the airway, breathing, circulation, and mental status. Following this primary examination, a secondary examination should be completed that includes obtaining historical and physical examination findings, laboratory tests, and appropriate bedside radiographs and ultrasonography. The abdominal physical examination in unstable patients may be unreliable because of distracting injuries, endotracheal intubation, or altered level of consciousness.

Assessing the Likelihood of an Abdominal Injury

Once the presence of abdominal trauma is established, additional information about the type of trauma mechanism (eg, fall or pedestrian hit by a vehicle) adds no information for identifying patients at increased or decreased risk of an abdominal injury.¹ The physician should focus on the physical examination because abdominal pain as a symptom does not confirm (LR 1.6; 95% CI, 1.3-2.0) or rule out an injury (LR 0.52; 95% CI, 0.34-0.79).² The most useful signs, laboratory results, and imaging result are shown in Table 88-1. When emergency physicians classify a patient as unlikely to have an abdominal injury based on their overall impression, the patient is less likely to have suffered an injury (LR 0.21; 95% CI, 0.11-0.42).³ A positive Focused Assessment With Sonography for Trauma (FAST) result is much better than the individual clinical examination findings and the overall clinical impression for identifying injured patients (LR 30; 95% CI, 20-46).