Does IV contrast extravasation on CT in anticoagulant-related rectus sheath and iliopsoas hematoma predict hematoma expansion and patient outcomes?

OBJECTIVE: The purpose of the study was to evaluate if IV contrast extravasation on CT in anticoagulant-related rectus sheath and iliopsoas hematoma predict hematoma expansion and patient outcomes. MATERIALS AND METHODS: All patients presented with anticoagulation-related spontaneous IP hematoma or RS hematoma and who underwent contrast-enhanced CT exploration, with injection of a contrast material, from January 2012 to January 2015 in our institution were included in this study. Considering the retrospective nature of our study, our institutional review board judged our study to be exempted from ethical approval and no patient consent was required. Computed tomography (CT) images were retrospectively analyzed blindly of the evolution and treatment of hematomas. The type of muscle involved; the presence of contrast extravasation after contrast injection; the volume of the hematoma, as well as, clinical and biological results (hemoglobin value g/dL); and for each patient, the type of anticoagulation used, patient's treatment and outcomes were noted. The analyses were conducted using R 3.1.0. All statistical tests were 2-sided, and probability values <0.05 were regarded as significant. RESULTS: Sixty-eight patients were reviewed. Among 68 patients, 44 (65%) patients presented spontaneous IP hematoma and 24/68 (35%) a RS hematoma. There were 37 men (54%) and 31 (46%) women, ranging from 39 to 93 years with a median age of 75 years. Hemodynamic instability was statistically associated with IP hematomas and large volume of hematoma (p < 0.001). Only 15 patients had follow-up CT, 10 without and with IV contrast, 2 with IV contrast only, and 3 without contrast. Follow-up CT was performed from J0 to J8. Detection of contrast extravasation did not appear related to hemodynamically instability (p = 0.35), to a neurological deficit (p = 1), or to the increase in the volume of the hematoma on follow-up CT (p = 0.81). The different types of anticoagulant were not related to muscular type more than the other (p = 0.9). Among anticoagulant therapy, only vitamin K antagonist therapy was statistically associated with surgery (p = 0.04). CONCLUSION: CT extravasation of contrast material in IP and RS hematoma does not appear to be related with clinical criteria of severity, and therefore should not be solely considered as a radiological decision criteria.