Jun 072013
 
Managing Anticoagulation Therapy For Surgery and Procedures

See also: How to manage anticoagulation perioperatively (ACCP Guidelines)

NOTE: Please read the Terms of Use before proceeding. If you are a patient, stop reading now; this site is for health care professionals only. If you are a health care professional, do not rely on this information as being current, peer-reviewed, or authoritative. The information that follows is a digest from the referenced sources; it is intended as a road map to guide physicians back to the appropriate medical literature, not to replace that literature. By the nature of medical research and opinion, the posted information may be or become outdated or incorrect at any time. Read the current primary literature and guidelines and seek expert consultation for anticoagulation decisions. Do not rely on this information or this website for this purpose. This post does not constitute medical advice. 

One in 50 people in the U.S. are taking long-term anticoagulation therapy for a condition like atrial fibrillation, a mechanical heart valve, or a clotting disorder resulting in DVT / PE. Millions more with coronary artery disease or strokes are taking antiplatelets drug like Plavix, and often aspirin as well. About 1 in 10 people on anticoagulation therapy undergo surgery or an invasive procedure each year, and the management of their anticoagulation medicines can be challenging: the physician is expected to simultaneously prevent serious bleeding during the surgery, and also clotting resulting in pulmonary embolism, heart attack, or embolic stroke. This is not possible in all cases, so decisions must be made on the basis of estimated relative risks. Even with "perfect" planning and adherence with an optimized approach, complications (bleeding or clotting) will still sometimes occur.

Procedures Not Necessarily Requiring Interruption of Anticoagulation

According to some experts, these procedures have a risk of serious bleeding < 1.5%, and if this is acceptable, anticoagulation may be continued with a target INR of 2.5. Some authors also advise that full-dose antiplatelet therapy (e.g., Plavix) may be continued through these procedures.

Arthrocentesis Bronchoscopy (Dx) EGD (mucosal bx OK) Cardiac cath (Dx)*
Thoracentesis Some FNAs* Colonoscopy (Dx) Endotracheal Intubation
Paracentesis IVC filter plcmt Minor skin surgery Colposcopy (Dx)
Central Lines Vas-Cath for HD Tooth extraction Dilation & curettage
PICCs Small abd/pelvis drains Root canals PEG,nephrostomy tube exchange

 * "controversial," say some authors

Procedures With High Bleeding Risk: Experts Advise Interrupting Anticoagulation

More-invasive surgeries and procedures are expected to cause serious bleeding in >1.5% of people taking anticoagulation therapy. Anticoagulation should be interrupted for these procedures, as well as those in body areas vulnerable to injury (e.g., spinal cord). Patients at high risk for clotting with anticoagulation interruptions should be considered for "bridging therapy" with heparin. This is not an exhaustive or authoritative list. 

Lumbar puncture Chest tube plcmt Arterial puncture Spinal/epidural anesthesia
Transbronchial bx Stricture dilations Organ biopsies Tunneled catheter plcmt
Cardiac ablations Liver/GB drains Nephrostomy ERCP w sphincterotomy
PEG tube plcmt Cardiac cath PCI Pacemaker plcmt >1cm polypectomy
Major surgery Wide skin excision Eye surgery (not cataracts) Vascular interventions
Decision-Making for Anticoagulation for Procedures & Surgery

Each patient's situation should be considered individually and he/she included in the decision making and risk discussion. Generally speaking, some experts have advised these principles:

For most patients undergoing low-bleeding-risk procedures:

  • Interruption of warfarin is not necessary;
  • The INR should be adjusted to ~2.5 if possible.
  • Antiplatelet therapy like Plavix may be continued.

For most patients undergoing high-bleeding-risk procedures:

  • For those who are at low individual risk for clotting, anticoagulation can be interrupted without bridging therapy (heparin).
  • Most patients at high individual risk of blood clots should receive bridging anticoagulation therapy.

Bridging therapy is strongly recommended for people with:

  • DVT or PE within the past 3 months or severe thrombophilia;
  • Mechanical mitral valves,
  • "Old" design mechanical aortic valves (caged-ball or tilting-disk design, i.e., non-bileaflet),
  • Any mechanical valve with a history of stroke or transient ischemic attack,
  • Non-valvular atrial fibrillation with a CHADS2 score 4 or greater, history of stroke or TIA, or cardiac thrombus.

The BRIDGE anticoagulation study in Circulation provides a nice table for risk stratifying these patients, and the below NEJM article has a similar reference table.

In people with recent DVT or PE (< 3 months since diagnosis), some experts advise delaying elective surgery for 3 months while anticoagulating. If surgery must be performed, consider bridging therapy, and in those who've received less than one month of anticoagulation, consider the placement of an IVC filter as well.

For patients taking dual antiplatelet therapy after placement of coronary artery stents (aspirin plus Plavix or a similar drug):

These patients are at increased risk for sudden coronary artery thrombosis in the stent with "early" discontinuation of antiplatelet therapy.  This risk is particularly elevated in the first 6-12 months after stent placement, especially for drug-eluting stents. This risk needs to be balanced against the necessity of the invasive procedure and its risk of causing serious bleeding. Some expert authors advise:

  • Postpone elective procedures / surgeries for at least 6 weeks after a bare-metal stent is placed, and for 6 months if a drug-eluting stent was placed.
  • If the procedure/surgery is high-bleeding-risk (see above), delay it as long as feasible -- optimally, more than a year after stent placement of any kind.
  • If a high-bleeding-risk procedure must be performed before completion of 6 weeks antiplatelet therapy (for bare-metal stents) or 6 months (for drug-eluting stents), it's recommended to continue both Plavix and aspirin throughout the invasive procedure whenever possible, and to never discontinue aspirin. There's no known effective reversal agent to prevent the massive bleeding that often results, but platelet transfusion may be tried. These are the most challenging scenarios.
  • After 6 weeks / 6 months of dual antiplatelet therapy (depending on stent type) have elapsed post-PCI, elective procedures can be performed after interrupting Plavix for 5 days pre-procedure (or longer for Effient/Ticlid), but continuing aspirin.
  • For low-bleeding-risk procedures (see above) in patients taking dual antiplatelet therapy, authors advise continuing both aspirin and the Plavix-type drug.

There is a lot more to this complex subject, which cannot be effectively summarized in any single article or online digest. The consequences of these medical decisions can be lifesaving or catastrophic. Read the literature and consult other specialist physicians before making decisions.

Read more:

Todd H. Baron, Patrick S. Kamath, and Robert D. McBane. Management of Antithrombotic Therapy in Patients Undergoing Invasive Procedures. N Engl J Med 2013; 368:2113-2124.

James D. Douketis et al. Bridging Anticoagulation: Is it Needed When Warfarin Is Interrupted Around the Time of a Surgery or Procedure? Circulation 2012; 125: e496-e498.

See also: How to manage anticoagulation perioperatively (ACCP Guidelines)

Get our weekly email update, and explore our library of practice updatesreview articles. and board review questions.

PulmCCM is an independent publication not affiliated with or endorsed by any other organization, society or journal referenced on the website. (Terms of Use | Privacy Policy)

Authors: contribute your work in a guest post.

0 Comments

Managing anticoagulation for surgery and invasive procedures (Review)