Ward Brent B, Smith Miller H
Department of Surgery, Section of Oral and Maxillofacial Surgery, University of Michigan, Ann Arbor, MI 48109, USA.
J Oral Maxillofac Surg. 2007 Aug;65(8):1454-60. doi: 10.1016/j.joms.2007.03.003.
To evaluate the current practice of oral and maxillofacial surgeons in Michigan regarding perioperative warfarin therapy and dentoalveolar surgery in defined procedure risk groups.
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.
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.
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.
评估密歇根州口腔颌面外科医生在特定手术风险组中围手术期华法林治疗及牙槽外科手术的当前实践情况。
向密歇根州口腔颌面外科协会注册的所有外科医生（n = 188）发放调查问卷。根据移植前肝功能衰竭患者手术积累的回顾性数据定义低/中/高手术风险组。我们询问了每位外科医生各风险组的最大耐受国际标准化比值（INR）。此外，还询问外科医生其对每组患者的常规做法是否包括围手术期继续或停用治疗性华法林。
应答率为72.6%。各风险组的平均最大INR临界值分别为：低风险组2.68，中风险组2.28，高风险组2.01。这些组中分别有23.6%、48.8%和70.5%的患者常规停用华法林。使用配对t检验，结果显示低、中、高风险组在患者管理实践方面存在统计学显著差异（P < .001）。
华法林治疗与牙槽外科手术缺乏一致性。迄今为止，尚无研究涉及大量中/高风险手术，无法为维持治疗性INR时的安全性提供循证支持。对于中高风险手术，大多数外科医生倾向于停用华法林并维持最低治疗水平或亚治疗水平，这种做法会增加血栓栓塞风险。基于这些初步数据，我们认为有必要进行一项前瞻性试验，以阐明针对中高风险手术人群更强有力的管理指南。
