Abstract

PURPOSE
The management of hemorrhagic shock is critical for trauma patients. To assess hemorrhagic shock, the clinician commonly uses a change in positional blood pressure, the shock index, an estimate of the diameter of inferior vena cava based on sonography, and an evaluation of hypoperfusion complex shown on a CT scan. To add the finding for the hypoperfusion complex, the 'halo sign' was introduced recently. To our knowledge, this 'halo sign' has not been evaluated for its clinical usefulness, so we designed this study to evaluate its usefulness and to find the useful CT signs for hypoperfusion complex.
METHODS
The study was done from January 2007 to May 2007. All medical records and CT images of 124 patients with trauma were reviewed, of which 103 patients were included. Exclusion criteria was as follows: 1) age < 15 year old and 2) head trauma score of AIS > or = 5.
RESULTS
The value of kappa, to assess the inter-observer agreement, was 0.51 (p < 0.001). The variables of the halo-sign-positive group were statistically different from those of the halo-sign-negative group. The rate of transfusion for the halo-sign-positive group was about 10 times higher than that of the halo-sign-negative group and the rate of mortality was about 6 times higher.
CONCLUSION
In the setting of trauma, early abdominal CT can show diffuse abnormalities due to hypoperfusion complex. Recognition of these signs is important in order to prevent an unwanted outcome in hemorrhagic shock. We conclude that the halo sign is a useful one for hypoperfusion complex and that it is useful for assessing the degree of hemorrhagic shock.

• Keywords: Shock indexHypoperfusion complexHalo signHemorrhagic shock