Post-Embolization Hemoglobin Changes: When to Consider Re-intervention.

PURPOSE: Decline in hemoglobin (Hgb) levels is common post-embolization, but there is no consensus on the classification of patients based on risk for re-bleeding or re-intervention. The current study evaluated post-embolization Hgb level trends with the goal of understanding the factors predictive of re-bleeding and re-intervention. MATERIALS AND METHODS: All patients who underwent embolization for gastrointestinal (GI), genitourinary, peripheral, or thoracic arterial hemorrhage from 01/2017 to 01/2022 were reviewed. Data included demographics, periprocedural pRBC transfusion (TF) or pressor requirements, and outcome. Lab data consisted of Hgb values pre-embolization, immediately post-embolization, and daily values on days 1-10 after embolization. Hgb trends were compared between patients across TF and re-bleeding outcomes. Regression model was used to examine factors predictive of re-bleeding and magnitude of Hgb reduction post-embolization. RESULTS: A total of 199 patients were embolized for active arterial hemorrhage. Perioperative Hgb level trends were similar for all sites and between TF + and TF- patients, showing a decline reaching a nadir within 6 days post-embolization followed by an upward trend. Maximum Hgb drift was predicted by GI embolization (p = 0.018), TF before embolization (p = 0.001), and use of vasopressor (p = 0.000). Patients with Hgb drop > 15% within the first two days post-embolization had a higher chance of having a re-bleeding episode (p = 0.04). CONCLUSION: Perioperative Hgb trends showed a consistent downward drift followed by an upward shift, irrespective of TF requirement status or site of embolization. Using a cut-off value of 15% Hgb reduction within the first two days post-embolization may be helpful to assess re-bleeding risk.