Brent B Ward1, Miller H Smith. 1. Department of Surgery, Section of Oral and Maxillofacial Surgery, University of Michigan, Ann Arbor, MI 48109, USA. bward@umich.edu
Abstract
PURPOSE: To evaluate the current practice of oral and maxillofacial surgeons in Michigan regarding perioperative warfarin therapy and dentoalveolar surgery in defined procedure risk groups. MATERIALS AND METHODS: Surveys were distributed to all surgeons (n = 188) registered with the Michigan Society of Oral and Maxillofacial Surgeons. Low/moderate/high surgery risk groups were defined based on retrospective data accumulated for procedures on pretransplant liver failure patients. We requested the surgeon's maximum tolerated International Normalized Ratio (INR) for each risk group. In addition, surgeons were asked if their routine practice for each group included continuation or discontinuation of therapeutic warfarin perioperatively. RESULTS: A 72.6% response rate was achieved. The average maximum INR cutoff values for the various risk groups were: low, 2.68; moderate, 2.28; and high, 2.01. Routine discontinuation of warfarin occurred in these groups 23.6%, 48.8%, and 70.5%, respectively. Using a paired t test, these results showed statistically significant differences in patient management practices (P < .001) between the low, moderate, and high risk groupings. CONCLUSION: Lack of uniformity exists regarding warfarin therapy and dentoalveolar surgery. No studies to date involve significant numbers of moderate/high risk procedures to provide evidence-based support of safety with maintenance of therapeutic INR. For moderate or high risk procedures, the majority of surgeons prefer warfarin discontinuation with minimally therapeutic or subtherapeutic levels, a practice that secondarily increases risk for thromboembolism. Based on these preliminary data, we believe a prospective trial to elucidate stronger management guidelines for both the moderate and high risk surgery population is indicated.
PURPOSE: To evaluate the current practice of oral and maxillofacial surgeons in Michigan regarding perioperative warfarin therapy and dentoalveolar surgery in defined procedure risk groups. MATERIALS AND METHODS: Surveys were distributed to all surgeons (n = 188) registered with the Michigan Society of Oral and Maxillofacial Surgeons. Low/moderate/high surgery risk groups were defined based on retrospective data accumulated for procedures on pretransplant liver failurepatients. We requested the surgeon's maximum tolerated International Normalized Ratio (INR) for each risk group. In addition, surgeons were asked if their routine practice for each group included continuation or discontinuation of therapeutic warfarin perioperatively. RESULTS: A 72.6% response rate was achieved. The average maximum INR cutoff values for the various risk groups were: low, 2.68; moderate, 2.28; and high, 2.01. Routine discontinuation of warfarin occurred in these groups 23.6%, 48.8%, and 70.5%, respectively. Using a paired t test, these results showed statistically significant differences in patient management practices (P < .001) between the low, moderate, and high risk groupings. CONCLUSION: Lack of uniformity exists regarding warfarin therapy and dentoalveolar surgery. No studies to date involve significant numbers of moderate/high risk procedures to provide evidence-based support of safety with maintenance of therapeutic INR. For moderate or high risk procedures, the majority of surgeons prefer warfarin discontinuation with minimally therapeutic or subtherapeutic levels, a practice that secondarily increases risk for thromboembolism. Based on these preliminary data, we believe a prospective trial to elucidate stronger management guidelines for both the moderate and high risk surgery population is indicated.
Authors: Wolfgang Eichhorn; Jens Burkert; Oliver Vorwig; Marco Blessmann; Georg Cachovan; Jürgen Zeuch; Marc Eichhorn; Max Heiland Journal: Clin Oral Investig Date: 2011-12-13 Impact factor: 3.573