Читать книгу Management of Complications in Oral and Maxillofacial Surgery - Группа авторов - Страница 60

 Etiology: vessel injury, undiagnosed vascular malformation, patient risk factors

 Management: pressure and packing, vessel ligation, electrocautery, bone wax, topical hemostatic agents, interventional radiology

The incidence of clinically significant bleeding as a result of third molar surgery ranges from 0.2% to 5.8% [4–6]. According to the AAOMS Age‐Related Third Molar Study, approximately 0.7% occur intraoperatively and 0.1% occur postoperatively [1]. Significant bleeding or hemorrhage is most often associated with mandibular third molar surgery (80%) when compared with maxillary third molar surgery (20%) [16]. Specific risk factors include advanced age, distoangular impactions, and deep impactions [6]. Massive intraoperative bleeding is a rare occurrence and is often attributed to the presence of an undiagnosed arteriovenous malformation (AVM) [16]. As such, examination of the surgical site for gingival discoloration, palpable thrill, or bruit is necessary. Imaging may demonstrate a multilocular radiolucency in the area of AVM. In these patients, angiography is essential to confirm diagnosis and treatment with embolization before the extraction is preferred.

The most common inherited bleeding disorder, von Willebrand disease, affects an estimated 1% of individuals. Hemophilia A or B is present in 1 in 5000 live births. Depending upon patient age and sex, the first surgical procedure a patient undergoes may be third molar extraction, and patients with mild to moderate forms of certain coagulopathies may have gone undiagnosed previously. Patients with acquired or congenital coagulopathy will require further workup prior to surgery. Depending upon the specific condition, recent laboratory values, coagulation factor replacement, hematology consultation, or inpatient surgery and hematological management schemes may be necessary.

Antithrombotic treatment with medications such as warfarin (Coumadin), clopidogrel (Plavix), and aspirin is commonly encountered among patients requiring extractions. Coumadin and Plavix rank among the top 100 prescribed medications in the United States, with an estimated 25% of individuals over age 75 currently on Coumadin, and according to the US Food and Drug Administration, over 100 billion aspirin pills are consumed each year. Most current literature does not recommend withholding these medications for uncomplicated tooth extraction. The risk of a thrombotic event outweighs any benefit of withholding the medication. In patients taking Coumadin, a preoperative INR (international normalized ratio) may be of value in assessing the current status of bleeding risk. According to Potoski, an INR value of 4.0 is acceptable for minor surgical procedures, an INR of 3.0 is preferred if the patient is also taking Plavix, aspirin, or another antiplatelet medication, and an INR of 2.5 is preferred for more involved or complex surgery where significant bleeding is anticipated [16].