What is the risk of bleeding in a patient with a history of bleeding disorders or on anticoagulant medications such as warfarin, aspirin, or clopidogrel (antiplatelet medications) undergoing a 24-hour pH study?

Risk of Bleeding During 24-Hour pH Study

The risk of bleeding during a 24-hour pH study is minimal to negligible, even in patients on anticoagulants or antiplatelet medications, as this is a diagnostic procedure without mucosal disruption. 1

Understanding the Procedure Risk Profile

A 24-hour pH study involves placement of either a catheter-based system or a wireless capsule to monitor esophageal acid exposure. The British Society of Gastroenterology guidelines specifically address this procedure and classify it differently based on the method used:

Catheter-Based pH Monitoring

• This carries essentially no bleeding risk as there is no tissue trauma or mucosal disruption 1
• The catheter is simply passed through the nose or mouth into the esophagus without any cutting, biopsy, or tissue manipulation 1
• No modifications to anticoagulant or antiplatelet therapy are required for catheter-based studies 1

Wireless pH Capsule Monitoring

• There may be a small increased risk of esophageal bleeding when the capsule is attached to the esophageal mucosa via suction 1
• The BSG guidelines note that "there may be an increased risk of oesophageal bleeding during or following wireless pH monitoring in patients taking antiplatelet agents, such as clopidogrel, and anticoagulants such as warfarin or direct acting oral anticoagulants" 1
• However, the guidelines acknowledge this is based on theoretical concern rather than documented cases, stating "in the absence of guidelines or data on this risk, we cannot make a categorical recommendation" 1

Management Recommendations for Patients on Antithrombotic Therapy

For Wireless pH Capsule Studies:

Patients should be counseled about the small theoretical increased bleeding risk, but routine discontinuation of antithrombotics is not mandated 1

• For warfarin: Ensure the INR is within therapeutic range (not above) prior to testing 1
• For aspirin (secondary prevention): Continue therapy, as the thrombotic risk of discontinuation far outweighs the minimal bleeding risk 2, 3
• For clopidogrel or other P2Y12 inhibitors: Individual risk-benefit assessment is needed, weighing the small bleeding risk against the thrombotic risk of discontinuation 1
• For DOACs: Consider individual assessment, though no specific data exists for this procedure 1

Clinical Context for Decision-Making:

The BSG guidelines recommend "following the BSG guidelines on antiplatelets and anticoagulants, if antiplatelets or anticoagulants are to be discontinued before wireless pH monitoring" 1. However, given that:

• Diagnostic endoscopy with mucosal biopsy (which involves actual tissue sampling) carries minimal bleeding risk even on continued antithrombotics 1
• No severe hemorrhage has been reported in thousands of patients undergoing diagnostic endoscopy with biopsies on aspirin, clopidogrel, or warfarin 1
• The wireless capsule attachment is less invasive than mucosal biopsy 1

The actual bleeding risk for wireless pH monitoring is likely extremely low, even on continued antithrombotic therapy.

Important Caveats and Pitfalls

Avoid Unnecessary Discontinuation of Antithrombotics:

• Discontinuing aspirin in patients on secondary prevention carries a nearly sevenfold increase in risk for death or acute cardiovascular events 2
• For patients with recent coronary stents, discontinuation of antiplatelet therapy dramatically increases stent thrombosis risk 2, 3
• The thrombotic risk of stopping antithrombotics almost always exceeds the minimal bleeding risk of this diagnostic procedure 1, 2

Specific High-Risk Scenarios Requiring Cardiology Consultation:

• Recent coronary stent placement (especially within 12 months) 2, 3
• Left main coronary artery stenting 2
• History of stent thrombosis 2
• Patients on dual antiplatelet therapy 2, 4

Bleeding Disorders:

• Patients with underlying bleeding disorders (hemophilia, von Willebrand disease, severe thrombocytopenia <50 × 10⁹/L) require individualized assessment 1
• The procedure itself poses minimal trauma, but these patients may have prolonged bleeding from even minor mucosal contact 1

Practical Algorithm

For patients requiring wireless pH capsule monitoring:

1. Assess cardiovascular risk:

   • Secondary prevention (prior MI, stroke, stent)? → Continue all antithrombotics 2, 3
   • Primary prevention only? → May consider holding aspirin 2

2. For warfarin patients:

   • Check INR within 24-48 hours before procedure 1
   • Proceed if INR is within therapeutic range (2.0-3.0) 1
   • Do not proceed if INR is supratherapeutic 1

3. Counsel patient:

   • Inform about small theoretical bleeding risk 1
   • Emphasize that no documented cases of significant bleeding exist in the literature 1
   • Discuss signs of bleeding to monitor for (chest pain, hematemesis, melena) 1

4. Document decision:

   • Record risk-benefit discussion 1
   • Note cardiovascular indication for antithrombotic therapy 2