Background: Compressive hematoma after thyroidectomy is a rare complication (1%) but can potentially be severe. The aim of this study was to search for risk factors, in particular the use of anticoagulants or antiplatelet medication, and to see if the delay of hematoma formation would require 1-day surgery performed in a careful manner.
Materials and methods: Retrospective review of 6,830 patients undergoing thyroidectomy in a single institution (1991 to 2006) identified 70 patients with hematomas requiring reoperation. Case controls (210 patients) were matched for age, gender, year of operation, type of thyroid disease, and type of operation. The notion of anticoagulant or antiplatelet medication was particularly studied. The delay of hematoma formation and the cause of bleeding were studied in univariate analysis by a chi-squared test and a Fischer's test.
Results: In univariate analysis, the formation of hematoma is not related to age, gender, type of thyroid disease, or type of bleeding. The pre or intraoperatory administration of anticoagulant or antiplatelet medication did not influence hematoma formation. Thirty-seven hematomas (53%) presented within 6 h postoperatively, 26 (37%) between 7 and 24 h and seven (10%) beyond 24 h.
Conclusion: Patients undergoing anticoagulant or antiplatelet treatment are not a high-risk population for hematoma formation. Forty-seven percent of the patients presented postoperative hematomas beyond 6 h postoperatively, leading to the conclusion that 1-day surgery is not safe.