0
Correspondence |

ResponseResponse FREE TO VIEW

Regina Kunz, MD, MSc (Epi); Alex C. Spyropoulos, MD, FCCP; Frederick A. Spencer, MD; Michael Mayr, MD; Amir K. Jaffer, MD, FHM; Mark H. Eckman, MD; Andrew S. Dunn, MD; James D. Douketis, MD, FCCP
Author and Funding Information

From the asim, Swiss Academy of Swiss Insurance Medicine (Dr Kunz), University Hospital Basel; Anticoagulation Services and Clinical Thrombosis (Dr Spyropoulos), North Shore/Long Island Jewish Health System at Lenox Hill Hospital; Division of Cardiology, Department of Medicine (Dr Spencer), McMaster University; Outpatient Department, Department of Medicine (Dr Mayr), University Hospital Basel; Department of Medicine, Miller School of Medicine (Dr Jaffer), University of Miami; Division of General Internal Medicine and Center for Clinical Effectiveness (Dr Eckman), University of Cincinnati; Division of Hospital Medicine, Icahn School of Medicine at Mount Sinai (Dr Dunn), The Mount Sinai Hospital; and Division of Hematology and Thromboembolism, Department of Medicine (Dr Douketis), McMaster University.

Correspondence to: Regina Kunz, MD, MSc (Epi), asim, Swiss Academy of Insurance Medicine, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland; e-mail: regina.kunz@usb.ch


Financial/nonfinancial disclosures: The authors of this guideline provided detailed conflict of interest information related to each individual recommendation made in this article. A grid of these disclosures is available online at http://chestjournal.chestpubs.org/content/141/2_suppl/e326S/suppl/DC1. In summary, the authors have reported to CHEST the following conflicts of interest: Dr Douketis was a consultant for Boerhinger-Ingelheim and served as a consultant during four advisory board meetings (by Sanofi-Aventis, Astra-Zeneca, Boehringer-Ingelheim, Pfizer) relating to the development and clinical use of novel, but not approved for clinical use, antiplatelet drugs (ticagrelor) and anticoagulant drugs (apixaban, semuloparin, dabigatran). Dr Eckman has received the following university grants: “Using Decision Analytic Modeling to Guide the ACCP Guideline Development Process for Antithrombotic Therapy in Atrial Fibrillation” (Foundation for Informed Medical Decision Making; October 2011-September 2013; $185,000); “Cost-Effectiveness of Screening for Chronic Hepatitis C Infection” (Merck/Schering-Plough; October 2011-September 2012; $58,000); “Greater Cincinnati BEACON Collaborative” (Office of the National Coordinator for Health Information Technology [90BC0016/01]; September 2010-March 2012; ∼ 15% effort); “Cincinnati Center for Clinical and Translational Science and Training (CTSA) ARRA Supplement for Development of Distance Learning Program in Medical Informatics” (National Institutes of Health [NIH]/National Center for Research Resources [NCRR] [UL1 RR026314-01S1]; August 2009-August 2011; ∼ 20% effort); “Cincinnati Center for Clinical and Translational Science and Training (CTSA)” (NIH/NCRR [1U54 RR 025216]; January 2009-February 2014; ∼ 15% effort); “A Patient Specific Decision Support Tool for Bariatric Surgery” (National Institute of Diabetes and Digestive and Kidney Diseases [K23 DK075599]; August 2007-June 2012; no financial support); National Heart, Lung, and Blood Institute (K23 HL085387; June 2008-March 2013; no financial support); and “Cost-Effectiveness of Screening for Chronic Hepatitis B Infection” (Gilead Sciences Inc; March 2008-August 2010; ∼ $56,000). He has also served as consultant for Savient Pharmaceuticals (“Cost Effectiveness Analysis of Gout Medication”; 2010; ∼ $300) and as editorial consultant for the ACP (“Physicians’ Information and Education Resource [PIER]: Module on Pre-Operative Assessment for Bleeding Disorders”; 2006-present; ∼ $250/year). Dr Spyropoulos has served as a consultant to Pfizer, Sanofi-Aventis, and EISAI. Dr Jaffer served as a consultant to sanofi-aventis, Janssen, Canyon Pharmaceuticals, Boehringer Ingelheim, and Daiichi Sankyo; he has formerly spoken on behalf of sanofi-aventis. Dr Jaffer is also on the steering committee of an NHLBI clinical trial. Dr Kunz is a member of the GRADE Working Group, the methodology of which is used in these guidelines. She has an interest in seeing this methodology applied. Drs Spencer, Mayr, and Dunn have reported that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.


Chest. 2013;144(4):1424-1426. doi:10.1378/chest.13-1728
Text Size: A A A
Published online
To the Editor:

We thank Dr Wahl et al for their comments expressing concern about a recommendation in our article1 in the Antithrombotic Therapy and Prevention of Thrombosis, 9th edition: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (AT9) (February 2012) on how to manage patients receiving vitamin K antagonists (VKAs) who need a minor dental procedure. The recommendation suggests that such patients “continue VKAs with co-administration of an oral prohemostatic agent or stopping VKAs 2 to 3 days before the procedure instead of alternative strategies (Grade 2C).”1 The authors request the removal of the second management option stopping VKAs 2 to 3 days before the procedure (which was an additional recommendation compared with previous guideline editions) because such a recommendation may expose patients to undue risks of thromboembolic complications.

Some background may help to reconcile the expressed concerns with the recommendations provided. Compared with previous guideline editions, the AT9 iteration is anchored on the more rigorous and explicit guideline methodology of the GRADE (Grading of Recommendations Assessment, Development and Evaluation) Working Group.2 In translating evidence into clinical practice recommendations, the GRADE approach involves a systematic literature search and data extraction process, coupled with documenting the confidence in the estimate (previously called quality of evidence) and the effects of the studies, pooled or unpooled, according to predefined outcomes and transparent judgments. The latter point incorporates the balance of the benefit vs risk and burden, the strength of the evidence, and patient values and preferences.

Anticipating limited evidence for the guideline question, we searched for randomized trials and observational studies examining the continuation of VKA in the periprocedural period, including studies where a prohemostatic agent was coadministered or where VKA was interrupted for 2 to 3 days to attenuate but not eliminate its anticoagulant effect (partial interruption). The retrieved evidence was sparse, of low to very-low quality, and allowed only indirect comparisons of the two treatment options. None proved superior with regard to the clinical outcomes of thromboembolic events or major, moderate, or minor bleeding.

Given these major limitations of the evidence, the guideline panel gave a weak grade 2C recommendation in favor of either intervention, to continue warfarin combined with a prohemostatic drug and for partial periprocedural VKA interruption. In the language of AT9, a 2C recommendation expresses the uncertainty of the evidence and implies that higher-quality research is likely to have an important impact on our confidence in the estimate of effect and may well change the estimate. It encourages the clinician to take additional considerations for individual patient management into account, such as availability of the oral prohemostatic agents and whether recent international normalized ratio values provide confidence that interrupting a VKA for 2 to 3 days would, in most instances, result in partial anticoagulation (international normalized ratio, 1.6-1.9).

We acknowledge the point from Dr Wahl et al that the partial interruption approach would not be feasible in some patients but, similarly, oral prohemostatic agents may not be available for other patients who may continue a VKA. They also make the point that multiple studies have demonstrated the safety of dental surgery (including tooth extractions) with local hemostatic measures, though the quoted studies had major methodologic limitations. Finally, although they suggest that partial VKA interruption may expose patients to serious thromboembolic complications, this premise is yet to be demonstrated in observational studies.3 The risk of complete (10-14 days) periprocedural VKA interruption with or without heparin bridging is being assessed in randomized controlled trials.

Without further evidence we will adhere to the weak recommendations of two alternative options to manage patients on VKA during the periprocedural period. We would encourage dentists and other clinicians to consider individual patient characteristics in deciding on the best management course, while acknowledging the high degree of uncertainty in the estimates of benefits, risks, and burdens of each option.

References

Douketis JD, Spyropoulos AC, Spencer FA, et al. Perioperative management of antithrombotic therapy: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines [published correction appears inChest. 2012;141(4):1129]. Chest. 2012;141(2_suppl):e326S-e350S.
 
Guyatt GH, Norris SL, Schulman S, et al. Methodology for the development of antithrombotic therapy and prevention of thrombosis guidelines: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest. 2012;141(2_suppl):53S-70S.
 
Garcia DA, Regan S, Henault LE, et al. Risk of thromboembolism with short-term interruption of warfarin therapy. Arch Intern Med. 2008;168(1):63-69. [CrossRef] [PubMed]
 

Figures

Tables

References

Douketis JD, Spyropoulos AC, Spencer FA, et al. Perioperative management of antithrombotic therapy: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines [published correction appears inChest. 2012;141(4):1129]. Chest. 2012;141(2_suppl):e326S-e350S.
 
Guyatt GH, Norris SL, Schulman S, et al. Methodology for the development of antithrombotic therapy and prevention of thrombosis guidelines: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest. 2012;141(2_suppl):53S-70S.
 
Garcia DA, Regan S, Henault LE, et al. Risk of thromboembolism with short-term interruption of warfarin therapy. Arch Intern Med. 2008;168(1):63-69. [CrossRef] [PubMed]
 
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543