[Hemostatic wound management in marcumar patients. Collagen fleece vs. tranexamic acid]

Randomized Clinical Trial Comparing Three Local Hemostatic Agents for Dental Extractions in Patients under Chronic Anticoagulant Therapy - A Comparative Study

Introduction

Oral anticoagulants are widely used worldwide for many systemic diseases. Recent oral surgical protocols suggest that therapeutic levels of the anticoagulant drug should be maintained for simple dental extractions because bleeding complications could be managed with proper local hemostasis. The aim of the present study was to compare bleeding complication of three different local hemostatic agents for dental extractions without interrupting drug administration in patients undergoing oral Vitamin K antagonist chronic anticoagulant therapy.

Material and Methods

Randomized control trial of three hemostatic agents for dental extractions, in patients under oral anticoagulant therapy without drug interruption. The present study included 240 patients with international normalized ratio between 1.5 and 3.5. Patients took their anticoagulation drug normally. A single surgeon performed calibrated simple dental extractions and applied a plug of bismuth subgallate (BS), fibrin tissue adhesive (FTA) or microfibrillar collagen (MC), assigned randomly. Statistical analysis of bleeding between the groups was performed using the Chi-square test.

Results

There was no hemorrhagic complication in the BS group, and only one in the FTA group. However, in the MC group, 10 patients (12.5%) suffered postoperative bleeding. Data analysis showed statistical differences between the MC group and the other two groups (P < 0.05).

Discussion

BS and FTA showed similar clinical effectiveness and were more effective than MC for the control of postoperative bleeding in oral anticoagulated patients.

Antifibrinolytic therapy for preventing oral bleeding in people on anticoagulants undergoing minor oral surgery or dental extractions

BACKGROUND

Individuals on continuous treatment with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) are at increased risk of bleeding complications during and after oral or dental procedures. Anticoagulant treatment is preferably continued at the same dose, since dose reduction or discontinuation of treatment is associated with an increased risk of thromboembolism. The use of haemostatic measures during or after the procedure (or both) could enable continuation of the oral anticoagulant treatment.

OBJECTIVES

We aimed to assess the efficacy of antifibrinolytic agents for preventing bleeding complications in people on oral anticoagulants undergoing minor oral surgery or dental extractions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Coagulopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. We searched PubMed, Embase and the Cochrane Library. Additional searches were performed using ClinicalTrials.gov, the International Clinical Trials Registry Platform (ICTRP), the CINAHL database of nursing and allied health services, the open access ProQuest dissertation database, papers and reports from the American College of Clinical Pharmacy (ACCP) and abstract books from annual scientific conferences.Date of last search: 04 January 2018.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials in people on continuous treatment with VKAs or DOACs undergoing oral or dental procedures using antifibrinolytic agents (tranexamic acid (TXA) or epsilon aminocaproic acid) to prevent perioperative bleeding compared to no intervention or usual care with or without placebo.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the titles and abstracts of all identified articles. Full texts were obtained from potentially relevant abstracts and two authors independently assessed these for inclusion based of the selection criteria. A third author verified trial eligibility. Two authors independently performed data extraction and risk of bias assessments using standardized forms. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

No eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures were identified.Three randomised trials and one quasi-randomised trial (follow-up in all was seven days) in people on continuous treatment with VKAs were included with a total of 253 participants (mean age 60 years). Two trials published in 1989 and 1993 compared the antifibrinolytic agent TXA with placebo in people using VKAs. Two other trials were published in 1999 and 2015 and compared TXA with gelatin sponge and sutures, and dry gauze compression, respectively. In all included trials, those who were treated with VKAs had international normalised ratio (INR) values within the therapeutic range and TXA was applied locally, not systemically.The two trials from 1989 and 1993 comparing TXA with placebo showed a statistically significant beneficial effect regarding the number of major postoperative bleeding episodes requiring intervention, with a pooled risk difference (RD) of -0.25 (95% confidence interval (CI) -0.36 to -0.14) (128 participants) (moderate-quality evidence). For the two trials that compared TXA with either gelatin sponge and sutures or with dry gauze compression, there was no difference between the TXA and the standard care group, RD 0.02 (95% CI -0.07 to 0.11) (125 participants) (moderate-quality evidence). The combined RD of all included trials was -0.13 (95% CI -0.30 to 0.05) (moderate-quality evidence). There were no side effects of antifibrinolytic therapy that required treatment withdrawal (128 participants) (moderate-quality evidence). Despite heterogeneity between trials with respect to the different haemostatic measures used in the control groups, the trials were comparable regarding design and baseline participant characteristics.Overall, we considered the risk of bias to be low in the trials comparing TXA with placebo and moderate in the trials comparing TXA with alternative haemostatic measures.

AUTHORS' CONCLUSIONS

Based on the results of this Cochrane Review, there seems to be a beneficial effect of locally applied TXA in preventing oral bleeding in people on continuous treatment with VKAs undergoing minor oral surgery or dental extractions. However, the small number of identified randomised controlled trials, the relatively small number of participants included in the trials and the differences in standard therapy and treatment regimens between trials, do not allow us to conclude definite efficacy of antifibrinolytic therapy in this population.We were unable to identify any eligible trials in people on continuous treatment with DOACs undergoing oral or dental procedures. Therefore, a beneficial effect of antifibrinolytic therapy can currently only be assumed based on data from the people using VKAs.

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.

Oral surgery during therapy with anticoagulants-a systematic review

OBJECTIVES

Oral anticoagulation therapy (OAT) with vitamin K inhibitors protects the patients from thromboembolic events. It may however lead to excessive hemorrhage during and after an oral surgery procedure. The aim of this systematic review was to evaluate the justifications to reduce, withdraw, or alter OATs prior to minor oral surgery procedures to manage bleeding events.

MATERIALS AND METHODS

A systematic MEDLINE search was conducted for clinical studies in English or German language from 1994 to 2014 comparing patients treated with OAT, without OAT, as well as patients with altered OAT for oral surgery purposes. Relevant outcome parameters were: postoperative local hemostasis, bleeding episodes, occurrence of thromboembolic events, and other complications due to the anticoagulation medication. A hand search for references cited in the identified publications completed the review.

RESULTS

After screening of 1755 abstracts, 16 clinical studies were identified according to the selection criteria. Due to the heterogeneity of the obtained data, aggregation and synthesis were not possible. There was no significant difference in bleeding events comparing patients under continued OAT to those with reduced, altered, and/or discontinued OAT medications. Minor bleeding events in the test and control groups were successfully stopped with local measures. However, no superiority of a single hemostatic measure could be identified. Neither the international normalized ratio (INR), within the therapeutic range (2-4), nor the extent of the minor oral surgery procedure had an influence on postoperative bleeding episodes.

DISCUSSION

There is strong evidence that OAT patients undergoing minor oral surgery should not discontinue their medication in order to prevent thromboembolic complications.

CLINICAL RELEVANCE

Nonetheless, INR should be less than 4, local hemostatic measures are of high importance and patients need to be instructed and closely monitored as minor bleedings might occur more often in OAT patients.

Bleeding complications after oral surgery in outpatients with compromised haemostasis: incidence and management

PURPOSE AND RESULTS: The aim of this prospective study was to determine the incidence of postoperative bleeding after oral surgery under local anaesthesia performed in outpatients with haemostatic disorders within a 5-year period (2003-2007). One hundred twenty one (70 males, 51 females) out of 2,056 outpatients with different haemostatic disorders (acquired or hereditary) were included in this study. The following data were recorded: medical history and general condition; medications; indication for the surgical procedure; specification of local anaesthesia; applied surgical techniques, considering the kind of haemostatic disorder; and peri- or postoperative bleeding complications. Postoperative bleeding was observed in 12 patients (9.9%). In three cases, inpatient treatment became necessary. The management of two patients with a haemostatic disorder (von Willebrand s disease and haemophilia A) is presented in short case reports.

CONCLUSION

In a heterogeneous group of 121 outpatients with known haemostatic disorders, a combination of a few haemostatic agents with appropriate operative technique enables an effective wound management. In cases of failed local interventions after postoperative bleeding, further diagnostic investigations are required.

In-vitro-Testung der Thrombozytenaggregation an zahnärztlich verwendeten kollagenen Hämostyptika

AIM

The aim of the present study was to evaluate the adhesion of thrombocytes to different collagenous hemostyptics in a new blood flow chamber.

MATERIAL AND METHODS

Three hemostyptics were tested: (1) Resorba (RE, native equine collagen, Resorba Wundversorgung GmbH, Nürnberg, Germany), (2) Hemocol (HE, native porcine collagen, Medical Biomaterial Products GmbH, Neustadt-Gleve, Germany), and (3) an experimental sponge (ES, chemically cross-linked porcine collagen, Geistlich Biomaterials, Wolhusen, Switzerland). Ten specimens of each sponge were exposed to a laminar 40 ml/h anticoagulated blood flow and adhering thrombocytes were examined using a confocal laser scanning microscope (CLSM). Pure collagen (Kollagen S, Roche) served as positive control and fetal calf serum (FKS, Roche) as negative control. Examination time was set at 0, 60, 120, and 180 s. Furthermore, pH measurements of defined sponge volumes were evaluated after incubation with NaCl and human blood serum after 3, 30, and 60 min.

RESULTS

All specimens showed a comparable amount of fluorescence units on the surface over time which was statistically not significantly different from the positive control (p>0.05, ANOVA). Nevertheless, acidity of all specimens could be observed after incubation with NaCl and in cases of HE and ES after incubation with human blood serum.

CONCLUSION

Within the limits of the present in-vitro study it was concluded that (1) all hemostyptics examined showed similar results in thrombocyte adhesion; (2) chemical cross-linking of collagen does not affect the thrombogenicity of the tested collagen; (3) however, the acidity might have a negative effect on thrombus formation in vivo.

Zahnextraktionen unter Medikation mit Acetylsalicylsäure (ASS)

PURPOSE

The purpose of this prospective study was to show and analyze the bleeding complications after teeth extraction under therapy with 100 mg acetylsalicylic acid (ASA) and to compare them to bleeding complications after teeth extraction in patients with a healthy blood profile.

PATIENTS AND METHODS

In 65 patients under medication with 100 mg ASA and in 252 healthy patients, 151/ 543 teeth were extracted and the bleeding complications monitored.

RESULTS

The postoperative bleeding frequency was 1.54% in the ASA 100 group and 1.59% in the healthy control group without any medication. No serious or uncontrollable postoperative bleedings arose in either group. All bleedings could be easily handled. No obvious difference concerning the bleeding frequency between the two groups was observed. The small number of bleeding events and the complexity of affecting parameters did not permit statistical tests.

CONCLUSION

It is not necessary to interrupt the medication of 100 mg acetylsalicylic acid given to prevent thromboembolism before tooth extractions.

Comparison of laboratory and immediate diagnosis of coagulation for patients under oral anticoagulation therapy before dental surgery

Background

Dental surgery can be carried out on patients under oral anticoagulation therapy by using haemostyptic measures. The aim of the study was a comparative analysis of coagulation by laboratory methods and immediate patient diagnosis on the day of the planned procedure.

Methods

On the planned day of treatment, diagnoses were carried out on 298 patients for Prothrombin Time (PT), the International Normalised Ratio (INR), and Partial Thromboplastin Time (PTT). The decision to proceed with treatment was made with an INR < 4.0 according to laboratory results.

Results

Planned treatment did not go ahead in 2.7% of cases. Postoperatively, 14.8% resulted in secondary bleeding, but were able to be treated as out-patients. 1.7% had to be treated as in-patients. The average error between the immediate diagnosis and the laboratory method: 95% confidence interval was -5.8 ± 15.2% for PT, -2.7 ± 17.9 s for PTT and 0.23 ± 0.80 for INR. The limits for concordance were 9.4 and -21.1% for PT, 15.2 and -20.5 s for PTT, and 1.03 and -0.57 for INR.

Conclusion

This study showed a clinically acceptable concordance between laboratory and immediate diagnosis for INR. Concordance for PT and PTT did not meet clinical requirements. For patients under oral anticoagulation therapy, patient INR diagnosis enabled optimisation of the treatment procedure when planning dental surgery.

[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.

Oral surgical management of patients with mechanical circulatory support

After the introduction of mechanical circulatory support (MCS) for treatment of patients with severe cardiogenic shock, the survival rate of these patients increased significantly. Temporary MCS may be applied over a period of several days up to months prior to heart transplantation (HTx). Oral surgical management of patients with MCS is seriously complicated by a combination of anticoagulant and antiaggregant medication. Moreover, contact of blood with artificial surfaces, i.e. polyurethane and silicone, may increase the risk of thromboembolic events and infections. A total of 32 patients with MCS (29 men and three women with a median age 48 years [range 27-60 years]) were examined for odontogenic foci, treatment needs and local and cardiovascular complications after oral surgical intervention. In 27 patients (84%) at least one potential focus was diagnosed. Following tooth extraction 4 out of 6 patients presented with local haemorrhage (n=3) and thromboembolic events (n=2). Generally MCS has to be considered a relative contraindication for elective oral surgical interventions.