Management of heparin therapy in the high-risk, chronically anticoagulated, oral surgery patient: a review and a proposed nomogram

Comparative Risk of Bleeding of Anticoagulant Therapy with Vitamin K Antagonists (VKAs) and with Non-Vitamin K Antagonists in Patients Undergoing Dental Surgery

OBJECTIVES

A wide variety of approaches have been proposed to manage anticoagulant drugs in patients undergoing dental surgery; vitamin K antagonists and novel direct oral anticoagulants have been used. The present study aims to explore the existing evidence concerning the management of patients in anticoagulant therapy undergoing oral surgery procedures and to give suggestions related to peri- and post-operative measures.

MATERIALS AND METHODS

A comprehensive search of databases was conducted to identify studies that evaluated the relationship between direct oral anticoagulants and dental procedures. The present scoping review was realized in adherence with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The publications varied from randomized controlled trials (RCT) to cohort trials. Only articles written in English language and published between 2000 to 2020 were screened. The studies were included if discussing the management of a patient in anticoagulant therapy (warfarin or direct oral anticoagulants) scheduled for tooth extraction.

RESULTS

33 studies were selected and included in the qualitative review. Nineteen considered anticoagulant therapy with warfarin, six considered anticoagulant therapy with new oral anticoagulants and eight compared patients taking warfarin with patients taking direct oral anticoagulants.

CONCLUSIONS

No case of extractive surgery should alter the posology of the drug: thromboembolic risks derived from discontinuation are heavier than hemorrhagic risks.

CLINICAL RELEVANCE

direct oral anticoagulants are safer in terms of bleeding and manageability and bleeding episodes are manageable with local hemostatic measures.

A prospective comparative study to assess the risk of postoperative bleeding after dental surgery while on medication with direct oral anticoagulants, antiplatelet agents, or vitamin K antagonists

Background

The aim of this prospective study was to investigate the occurrence and severity of postoperative bleeding following dentoalveolar surgery in patients with uninterrupted anticoagulation therapy (AT).

Methods

Patients receiving AT (vitamin k antagonist (VK), direct oral anticoagulants (DOAC) or antiplatelet therapy (APT) and in need of surgical intervention classified as A, B or C (single or serial tooth extraction, osteotomy, or implant placement) were studied between 2019 and 2021. A healthy, non-anticoagulated cohort (CG) served as a control group. The main outcomes measured were the frequency of postoperative bleeding, the classification of the severity of postoperative bleeding (1a, 1b, 1c, 2, 3), and the correlation with the AT surgical intervention classification.

Results

In total, 195 patients were included in the study, with 95 patients in the AT group and 100 in the CG. Postoperative bleeding was significant in the AT group vs. the CG (p = 0.000), with a significant correlation with surgical intervention class C (p = 0.013) and the severity class of bleeding 1a (p = 0.044). There was no significant correlation with procedures of type A, B or C for the other postoperative bleeding gradations (1b, 1c, 2 and 3). There was a statistically significant difference in the occurrence of postoperative bleeding events between the DOAC/APT group and the VK group (p = 0.036), but there were no significant differences regarding the other AT agents.

Conclusion

The continuation of anticoagulation therapy for surgical interventions also seems reasonable for high-risk interventions. Although significantly more postoperative bleeding occurs, the severity of bleeding is low. The perioperative management of anticoagulated patients requires well-coordinated interdisciplinary teamwork and detailed instruction of patients.

Clinical trial registration The study is registered (29.03.2021) at the German clinical trial registry (DRKS00024889).

Management of anticoagulated patients in dentoalveolar surgery: a retrospective study comparing bridging with heparin versus unpaused vitamin K antagonist medication

Background

The aim of this study was to investigate the occurrence of postoperative bleeding following dentoalveolar surgery in patients with either continued vitamin K antagonist medication or perioperative bridging using heparin.

Methods

A retrospective study was performed analyzing patients who underwent tooth extraction between 2012 and 2017. Patients were retrospectively allocated into two comparative groups: un-paused vitamin K antagonist medication versus bridging using heparin. A healthy, non-anticoagulated cohort with equivalent surgery served as a control group. Main outcome measures were: the occurrence and frequency of postoperative bleeding, the number of removed teeth, the surgical technique of tooth removal (extraction/osteotomy/combined extraction and osteotomy) and the prothrombin time.

Results

In total, 475 patients were included in the study with 170 patients in the group of un-paused vitamin K antagonist medication VG, 135 patients in the Bridging group BG and 170 patients in the control group CG. Postoperative bleeding was significant: CG versus VG p = 0.004; CG versus BG p < 0.001, BG versus VG p < 0.001. A significant correlation of number of the extracted teeth in the BG (p = 0.014) and no significance in VG (p = 0.298) and CG (p = 0.210) and in the BG versus VG and CG with p < 0.001 in terms of surgical intervention extraction. No difference observed in terms of prothrombin time.

Conclusions

Bridging with heparin increases the risk for bleeding compared to un-paused vitamin K antagonist medication. The perioperative management of anticoagulated patients requires a well-coordinated interdisciplinary teamwork to minimize or at best avoid both: postoperative bleeding and thromboembolic incidences.

Management of anticoagulated patients in dentoalveolar surgery: a clinical comparative study

OBJECTIVES

This prospective, comparative, clinical study analyzed the postoperative bleeding risk of patients on anticoagulation therapy (AT) who were undergoing tooth extractions and osteotomies.

MATERIALS AND METHODS

Patients with the following ATs were included (test groups): (1.) platelet aggregation inhibitors (PAIs), (2.) vitamin K inhibitors, (3.) low molecular weight heparin (LMWH), and (4.) direct oral anticoagulants (DOACs). Patients in the control group were not on any AT (non-AT group). Patients were subdivided into the following treatment groups: (1.) single tooth extraction, (2.) serial extraction (≥ 2 adjacent teeth), and (3.) tooth osteotomy. Pre-, intra-, and postoperative data concerning the treatment, extent of the surgery, and bleeding were recorded and statistically evaluated.

RESULTS

There were 15 postoperative bleeding events in 838 patients (1.7%): four (0.7%) in the non-AT group (n = 603 patients) and 11 (4.7%) in the AT group (n = 235 patients). The surgical procedure had no statistically significant effect on postoperative bleeding frequencies. Patients taking vitamin K inhibitors had a significantly higher risk of postoperative bleeding compared with patients without AT (p < 0.00001). Four patients were hospitalized due to the severity of the bleeding (vitamin K inhibitor group). Postoperative bleeding events were all controlled with local hemostatic measures.

CONCLUSIONS

The postoperative bleeding risk after tooth extractions and osteotomies in patients continuing AT is low, and bleeding can be controlled with local hemostatic measures.

CLINICAL RELEVANCE

AT should be continued in patients undergoing tooth removal procedures under the provision that local hemostatic measures are applied.

Management of anticoagulated patients in implant therapy: a clinical comparative study

OBJECTIVES

This prospective clinical comparative study aimed to analyze the postoperative bleeding risk of patients continuing their anticoagulation therapy (AT) and undergoing implant surgery and bone grafting procedures.

MATERIALS AND METHODS

The treatments ranged from the insertion of single or multiple dental implants over implant exposures to sinus floor augmentation and vertical and/or lateral bone grafting with autologous bone grafts. The patients of the test groups (AT groups) were treated with platelet aggregation inhibitors (PAIs), Vitamin-K inhibitors, Vitamin-K inhibitor withdrawal bridged with heparin (LMWH), or new/direct oral anticoagulants (NOACs/DOACs). Patients of the control group were non-anticoagulated (non-AT group). Surgical procedures were performed in the same manner in all groups. Pre, intra, and postoperative data concerning the treatment, extent of the surgery and bleedings was recorded and statistically evaluated.

RESULTS

There were seven postoperative bleedings in 564 patients (1.2%), four in the AT groups (3.4%), and three in the non-AT group (0.6%). No thromboembolic complication occurred in the whole observation period. The invasiveness of the surgical procedure had no statistically significant effect on bleeding frequencies. Patients taking Vitamin-K inhibitors had a significantly higher risk of a postoperative bleeding compared to patients without any AT (P = 0.038). Two patients were hospitalized due to the severity of the bleeding as a precautionary measure (one in the non-AT and one in the PAI group). All bleedings were easily controllable with local hemostatic measures. There was no postoperative bleeding recorded for patients taking DOACs.

CONCLUSIONS

Anticoagulation therapy should be continued in patients undergoing implant surgery and bone grafting procedures avoiding thromboembolic complications. Surgeons should always apply the most minimally invasive approach to reduce postoperative risks and be able to apply local hemostatic measures in terms of a bleeding complication.

The dental patient on oral anticoagulant medication: a literature review

Specific diseases and medications may considerably influence the delivery of oral care and the course of dental therapy. The purpose of this literature review is to examine the relationship between oral anticoagulant medication and dental treatment. Electronic and manual searches were conducted for clinical studies in the English literature for the years 1988-2010. The review process provided a total of 110 pertinent literature references, out of which 38 studies dealt with oral anticoagulants and dental treatment. Different treatment strategies relative to dental periprocedural anticoagulation regimens have been identified, and their accompanying thromboembolic and bleeding risks are being presented and discussed. Regarding to what extent a safe and successful dental treatment in patients on anticoagulant medication is feasible, the level of evidence is lacking. Until high-level data are provided, an individualised treatment approach after consultation with the physician of the patient is highly recommended.

Dentoalveolar Procedures for the Anticoagulated Patient: Literature Recommendations Versus Current Practice

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.

[Tooth extraction and anticoagulants]

INTRODUCTION

The purpose of this study was to show the possibility of extracting teeth without modifying the anticoagulant treatment (anti-platelet and anti-vitamin K agents).

MATERIAL AND METHOD

Two hundred patients underwent dental extraction from May 2003 to July 2006 without modifying their anticoagulant treatment; only 137 of them were hospitalized. Most of the teeth were extracted under local anesthesia, and hemostatic pad were inserted in the sockets without suture.

RESULTS

One thousand (and) sixteen extractions were performed with bleeding disorders in 4%, successfully resolved by using local hemostatics.

DISCUSSION

Modifying an anticoagulant treatment is a thrombo-embolic complication risk factor. Performing tooth extraction according to our protocol decreases this risk and bleeding complications, thus proving the validity of our technique.

Periprocedural bridging therapy in patients receiving chronic oral anticoagulation therapy

BACKGROUND

In patients receiving chronic oral anticoagulation with vitamin K antagonists (VKAs) it may be necessary to temporarily discontinue VKA therapy to allow surgery or other invasive procedures to be performed, as maintaining treatment may increase the risk of bleeding during the procedure. This, however, creates a clinical dilemma, since discontinuing VKAs may place the patient at risk of thromboembolism.

SCOPE

We undertook a systematic narrative review of patients on chronic oral anticoagulation, requiring a periprocedural bridging therapy with heparin during invasive procedures.

FINDINGS AND RECOMMENDATIONS

For patients requiring temporary discontinuation of VKA, current guidelines recommend the use of 'bridging' therapy with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) in patients considered to be at intermediate-to-high risk of thromboembolism, such as those with prosthetic heart valves or atrial fibrillation. Recent studies show that LMWHs are associated with low rates of thromboembolism and, when compared with UFH, are as effective and safe as UFH when used as periprocedural bridging therapy in such patients. LMWHs also offer advantages such as ease of administration and predictable anticoagulant effects. Moreover, outpatient-based periprocedural bridging therapy with LMWH has been shown to result in significant cost savings compared with in-hospital UFH.

CONCLUSIONS

The decision to provide bridging therapy requires careful consideration of the relative risks of thromboembolism and bleeding in each patient. Based upon the studies reviewed we recommend a therapeutic dose of UFH or LMWH for patients at intermediate-to-high thromboembolic risk requiring interruption of VKA, especially for low bleeding risk procedures. We would like to propose upgrading the American College of Chest Physicians (ACCP) guideline recommendations from 2C to 1C. However, there is still a need for a randomized controlled trial on the efficacy and safety of the available bridging strategies, including heparin and placebo comparators, in preventing thromboembolism for specific patients and procedures.

[Intraoperative adverse events in minor oral surgery. Risk analysis]

AIM OF THE STUDY

The aim of this prospective study was to evaluate oral surgical procedures performed as day surgery under local anesthesia. We examined patients' general condition, and besides checking for intraoperative complications we analyzed postoperative bleeding in patients with hemostatic disorders.

PATIENTS

The patient population consisted of 1540 patients (797 female, 743 male), who underwent a total of 2055 minor oral surgical procedures over a 5-year period (1998-2002). Before the treatment started a data file was made for each patient, which contained information on his or her past medical history, concomitant medication, why the operation was indicated, premedication, anesthetic and surgical techniques applied, and postoperative treatment.

RESULTS

Systemic pathologies influencing surgical decisions were found in 316 patients (20.5%), affecting 676 interventions (32.9%). In 109 patients (5.3% of the 2055) altered hemostasis was found. The surgical procedures recorded were: (operative) tooth extraction (n=394), interventions for surgical conservation of teeth (n=272), treatment for cysts (n=140), surgical revisions (n=46) and preprosthetic surgery (n=19). Passing complications, mostly systemic in nature, occurred during 27 sessions of local anesthesia (1.3%). There were 87 adverse events intraoperatively (4,2%), most of which were confined to the surgical field; specifically 15% of these complications took the form of hemorrhage. We observed no significant correlation between the occurrence of intraoperative complications and patients' gender, predisposing systemic pathologies including bleeding disorders, or age. Postoperative hemorrhage was observed significantly more frequently in patients with impaired hemostasis and required admission to hospital for inpatient treatment in 2 cases.

CONCLUSION

According to our investigation, oral surgery can be performed in patients with compromised general condition with as few intraoperative complications as in patients with no general medical problems. However, in individual cases specific risk factors can be present and oral surgery may be temporarily contraindicated, at least as day surgery.

Hemostatic effect of n-butyl-2-cyanoacrylate (histoacryl) glue in warfarin-treated patients undergoing oral surgery

PURPOSE

Our goal was to evaluate the local hemostatic effect of n-butyl-2-cyanoacrylate (Histoacryl; B. Braun, Melsungen, Germany) glue in warfarin-treated patients who undergo outpatient oral surgery without a change in their level of anticoagulation.

MATERIALS AND METHODS

Thirty consecutive warfarin-treated patients randomly assigned to study and control groups and 10 patients who had never been on anticoagulant therapy serving as the negative control group were included in this trial. Before multiple teeth extractions, all patients had a prothrombin time and the international normalized ratio (INR) determined. To gain hemostasis and primary closure, gelatin sponge and multiple interrupted resorbable sutures were used in the control and negative control groups, and Histoacryl glue and the minimal number of interrupted resorbable sutures were used in the study group. Postoperatively, patients were to contact the oral surgeon if abnormal bleeding occurred. Patients who did not have postoperative bleeding were seen on the 10th postoperative day. Data were collected, and statistical differences in age and gender distributions, number of teeth extracted, INR levels, and bleeding that required treatment were analyzed with the Mantel-Haenzel test. Statistical significance was defined as a value of P <.05.

RESULTS

Local hemostasis was obtained immediately in study patients and only after 10 to 20 minutes in the control and negative control patients. In relation to bleeding complications, there were no cases of postoperative bleeding requiring treatment in both the negative control patients and study patients. In the control patients, 5 cases had postoperative spontaneous bleeding that required treatment. This difference was statistically significant. No patient had wound infection and the healing process appeared to be normal.

CONCLUSION

Multiple extractions can be performed in patients taking oral anticoagulant therapy without a change in their level of anticoagulation provided an efficient local hemostatic measure is instituted. And, in this regard, Histoacryl glue, used as a topical adhesive over approximated wound edges, is an effective and easily applicable local hemostatic for oral surgery in such patients.

Oral surgery in patients on anticoagulant therapy

OBJECTIVE

Surgery is the main oral healthcare hazard to the patient with a bleeding tendency, which is mostly caused by the use of anticoagulants. The traditional management entails the interruption of anticoagulant therapy for dental surgery to prevent hemorrhage. However, this practice may increase the risk of a potentially life-threatening thromboembolism. Because this issue is still controversial, it is the aim of this paper to review the evidence, to highlight the areas of major concern, and to suggest management regimens for patients on the 3 main types of anticoagulants: coumarins, heparins, and aspirin. MATERIALS REVIEWED: The pertinent literature and clinical protocols of hospital dentistry departments have been extensively reviewed and discussed.

RESULTS

Several evolving clinical practices in the last years have been detected: anticoagulant use is generally not discontinued; oral surgery is performed despite laboratory values showing significant bleeding tendency; new effective local methods are used to prevent bleeding; and patients at risk are referred to hospital-based clinics.

CONCLUSION

The management of oral surgery procedures on patients treated with anticoagulants should be influenced by several factors: extent and urgency of surgery, laboratory values, treating physician's recommendation, available facilities, dentist expertise, and patient's oral, medical, and general condition.

Dental extractions in patients maintained on oral anticoagulant therapy: comparison of INR value with occurrence of postoperative bleeding

The purpose of this study was to evaluate the incidence of postoperative bleeding in patients treated with oral anticoagulant medication who underwent dental extractions without interruption of the treatment and to analyze the incidence of postoperative bleeding according to the International Normalized Ratio (INR) value. The 249 patients who underwent 543 dental extractions were divided into five groups: Group 1 with INRs of 1.5-1.99, Group 2 with INRs of 2-2.49, Group 3 with INRs of 2.5-2.99, Group 4 with INRs of 3-3.49 and Group 5 with INRs>3.5. The INR was measured on the day of the procedure. Local haemostasis was carried out with gelatin sponge and multiple silk sutures. Of the 249 patients, 30 presented with postoperative bleeding (12%): Group 1, three patients presented with bleeding (5%), Group 2, 10 patients (12.8%), Group 3, nine patients (15.2%), Group 4, five patients (16.6%) and Group 5, three patients (13%). The incidence of postoperative bleeding was not significantly different among the five groups. The value of the INR at the therapeutic dose did not significantly influence the incidence of postoperative bleeding. Thus, dental extractions can be performed without modification of oral anticoagulant treatment. Local haemostasis with gelatin sponge and sutures appears to be sufficient to prevent postoperative bleeding.