Management of oral Anticoagulant and Antiplatelet drugs in patients attending for elective Endoscopy

• General Points
• Flow chart for anticoagulated patients
• Patients on warfarin referred for low risk procedure - elective gastroscopy or flexible sigmoidoscopy
• Patients on warfarin for 'low risk conditions' (Box 1) referred for 'high risk procedure' (Box 2) - elective colonoscopy, ERCP, or for Endoscopy with intended therapy or multiple biopsies (eg Barrett's surveillance).
• Patients on warfarin for 'high risk conditions' (Box 3) referred for 'high risk procedure' (Box 3).
• Antiplatelet therapy and elective procedures
• Flow chart for patients on anti-platelet agents
• Appendix 1: Pathway for Endoscopy admin staff on receipt of request
• Appendix 2: Letter to the GP advising regarding stopping warfarin and bridging with LMWH
• Appendix 3: Timeline letter for patients stopping warfarin and bridging with heparin

General Points

• This advice relates to elective endoscopic procedures for patients on anticoagulation therapy (warfarin or the direct oral anti-coagulant agents: ‘DOACs’ such as dabigatran, apixaban, edoxaban or rivaroxaban) or anti-platelet therapy (aspirin and P2Y12 receptor antagonists such as clopidogrel). They reflect the 2021 BSG guidelines on this topic. More information and the rationale for the LTHT guidelines can be found in the BSG guidelines. For acute gastrointestinal haemorrhage, please refer to the separate LTHT guidelines.
• Throughout the document, any guidance regarding clopidogrel also applies to prasugrel and ticagrelor.
• Decisions regarding the management of anticoagulation therapy prior to Endoscopy are the responsibility of the referring clinician. Thus, these guidelines are relevant to all clinicians who refer patients for elective outpatient Endoscopy. This is because the referring clinician knows most about why the patient is anticoagulated and what procedures he/she expects to be performed at the Endoscopy. Clinicians should seek advice from Cardiology, Haematology or Gastroenterology consultants as necessary.
• If the information on the request is deemed inadequate by Endoscopy staff to organise the procedure, an email will be sent to the referring consultant, and if necessary after 1 week the endoscopy referral will be returned (see Appendix 1).
• Guidance in relation to anticoagulation and anti-platelet medication depends on the risk of haemorrhage during the procedure (high or low risk) and the risk of discontinuing medication (high and low risk). See boxes 1 - 3.
• The endoscopist takes responsibility for the safety of the procedure and the immediate aftercare until the patient leaves the Endoscopy unit. The endoscopist may cancel the procedure if he / she is not convinced that it is safe to proceed.
• Summaries of the guidelines are also given in the flow charts (Figures 1 and 2).

Back to top

Flow chart for anticoagulated patients

Enlarge Image

Figure 1: Management of warfarin or direct oral anticoagulents (DOACs) in patients undergoing endoscopic procedures (taken from the BSG guidelines. Please note: procedures in which large numbers of biopsies are anticipated (eg Barrett’s surveillance) are categorised as ‘high risk’ for bleeding).
Tractional PEG removal, which is generally performed by non-medical staff, is included as high risk due to the potential bleeding risk.

Back to top

Patients on warfarin referred for low risk procedure - elective gastroscopy or flexible sigmoidoscopy

• The referring physician should discuss the issue of anticoagulation with the patient
• Patients referred for diagnostic procedures can usually be advised to continue on anticoagulation.  
• It is safe to take small numbers (4-6) of biopsies at therapeutic INR levels.
• However, patients should be told that if a lesion is found which requires sampling or removal, a second procedure may be required.
• Patients should be told to attend anticoagulation clinic 1 week before the Endoscopy for an INR check, and to bring their anticoagulation letter or book with their results with them to Endoscopy. For patients under the Leeds anticoagulant service their INR and dose should be visible on PPM+ titled “dose and nxt appoint’t/INR.

• If INR is in the therapeutic range continue usual dose

• If INR is above the therapeutic range but < 5 the dose should be reduced (at the anticoagulation clinic) until the INR is in the therapeutic range.

• If INR > 5 the anti-coagulation clinic should be contacted to omit/reduce doses as needed so that the procedure can be undertaken safely, provided that the INR check in Endoscopy on the day of the procedure is within the therapeutic range..

• INR will be checked on day of procedure in Endoscopy, prior to their procedure.

• Patients on warfarin for ‘low risk conditions’ referred for ‘high risk procedure’- see Box 1 - elective colonoscopy, ERCP, or for Endoscopy with intended therapy or multiple biopsies (eg Barrett's surveillance)

• The referring physician should discuss the issue of anticoagulation with the patient 
• Patients who are anticoagulated with warfarin for ‘low risk indications’ (see Box 1) are generally advised to stop anticoagulation 5 days before the examination.
• If the patient is an in-patient please review the VTE risk assessment and prescribe LMWH (if required) once INR is < 2.
• If the risk of stopping anticoagulation is uncertain, the referrer may seek advice from the team which commenced the anticoagulation therapy.
• INR should be checked to be < 1.5 before the procedure; for outpatients this will be done in Endoscopy prior to the procedure.

• The endoscopist recommends when warfarin should be restarted - usually restart the night of the procedure at either usual daily dose, or usual daily dose +50% for 2 days, then usual dose thereafter.
• Patient to attend anticoagulation clinic 1 week after procedure.

NB diagnostic colonoscopy can be performed as a low risk procedure as in Figure (1), so long as the patient is informed of the possible need to repeat the procedure if polyps are found.

Back to top

Patients on warfarin for 'low risk conditions' (Box 1) referred for 'high risk procedure' (Box 2) - elective colonoscopy, ERCP, or for Endoscopy with intended therapy or multiple biopsies (eg Barrett's surveillance).

Back to top

Patients on warfarin for 'high risk conditions' (Box 3) referred for 'high risk procedure' (Box 3).

• The referring physician discusses the issue of anticoagulation with the patient
• Anticoagulation with warfarin is discontinued 5 days before the elective procedure.
• 2 days after stopping warfarin (3 days before the procedure) heparin (generally low molecular weight heparin (LMWH: enoxaparin) at therapeutic dose) is started and continued following the endoscopy until oral anticoagulation is at the appropriate therapeutic level.
• LMWH can be prescribed in hospital (if patients live in Leeds they are generally sent to the anticoagulant clinic at SJUH to organise bridging with enoxaparin). If patients live outside Leeds, bridging is organised via the GP surgery and alternative LMWH may be used according to local protocol.  
• LMWH should be prescribed in the mornings and omitted on day of procedure
• INR should be checked before the procedure to be < 1.5.
• The endoscopist should recommend when anticoagulation is to be restarted.

For any patients on long term low dose (prophylactic) LMWH, this can be continued prior to any low or high risk procedure.

For patients on long term full dose (therapeutic) LMWH the LMWH is omitted the night before, unless the referring clinician feels that it would be too high risk to stop.

Back to top

DIRECT ORAL ANTICOAGULANTS (DOACs) AND ELECTIVE PROCEDURES

• Patients who have started anticoagulation in the last 3 months for a new thromboembolic event  should not have their anticoagulation stopped. If the procedure is urgent their case should be discussed with haematology
• For low-risk endoscopic procedures the morning dose of DOAC should be omitted on the day of the procedure. This applies to both once daily and twice daily DOAC regimes.
• For high-risk endoscopic procedures the last dose of DOAC should be taken at least 72 hours before the procedure.  For high-risk endoscopic procedures, in patients on dabigatran with eGFR of 30–50 mL/min the last dose should be taken 5 days prior to the procedure.
•  In any patient with a creatinine clearance <30mls/min, or rapidly deteriorating renal function a haematologist should be consulted.
• DOACs  will usually be restarted the day after a low risk procedure, but may be delayed until 48 hours or more post-procedure after high risk procedures, bearing in mind their rapid onset of action (unlike warfarin).

Back to top

Antiplatelet therapy and elective procedures

Flow chart for patients on anti-platelet agents

Enlarge Image

Figure 2:  Management of anti-platelet agents in patients undergoing endoscopic procedures

• Antiplatelet therapy with aspirin and/or dipyridamole are safe to continue for both diagnostic and therapeutic procedures. However, to avoid any confusion, if patients are on aspirin plus dipyridamole, dipyridamole is generally stopped for 7 days before a therapeutic procedure, as per guidelines for other dual anti-platelet therapy. NB The exception to the above is ampullectomy; 2021 BSG guidelines indicate that all anti-platelet/anti-thrombotic agents should be stopped prior to ampullectomy, due to the high bleeding risk.

1) Patient on clopidogrel (with or without aspirin), low risk procedure - elective gastroscopy and flexible sigmoidoscopy, diagnostic colonoscopy

• The referring physician discusses the issue of continuing antiplatelet therapy with the patient.
• Patients are usually advised to continue taking the antiplatelet agents.
• Patients should be told that if a lesion is found which requires multiple biopsies or removal, a second procedure would probably be required.
• The referring clinician should consider whether it would be more appropriate to arrange a CT colonography in patients on dual anti-platelet therapy to identify polyps so that a plan can be made for stopping one agent prior to polypectomy

2) Patient on clopidogrel, high risk procedure (ERCP and therapeutic endoscopic procedures)

• Clopidogrel should usually be discontinued before therapeutic endoscopy unless patient has a high risk condition. The current BSG guidelines indicate that cold snare polypectomy for small polyps may be considered in patients on clopidogrel (without aspirin); this would be followed by clipping to reduce the risk of post-polypectomy bleeding. Procedures in which large numbers of biopsies are anticipated (eg Barrett’s surveillance) are also categorized as ‘high risk’.
• The referring physician discusses the issue of anti-platelet therapy with the patient and if necessary the cardiologist.
• The patient should be advised to stop clopidogrel 7 days before the endoscopy.
• Aspirin should be continued, or can be used to replace the clopidogrel if patient not already on it.
• Clopidogrel should not be discontinued:

• < 12 months after insertion of a drug-eluting coronary stent

• <1 month after insertion of bare metal coronary stent

• Clopidogrel should be restarted at the endoscopist’s discretion, usually the day after the procedure.

Back to top

Appendix 1: Pathway for Endoscopy admin staff on receipt of request

Back to top

Appendix 2: Letter to the GP advising regarding stopping warfarin and bridging with LMWH

Back to top

Appendix 3: Timeline letter for patients stopping warfarin and bridging with heparin

Back to top