What is the bleeding risk for glaucoma procedures, particularly in patients on anticoagulant therapy like apixaban (apixaban)?

Glaucoma Procedures: Bleeding Risk Classification

Glaucoma procedures are classified as low-to-moderate bleeding risk procedures with a 30-day major bleeding risk of 0-2%, and ophthalmological procedures (including cataract surgery) are specifically listed as minimal bleeding risk procedures in standardized perioperative anticoagulation guidelines. 1

Bleeding Risk Stratification

Minimal Bleeding Risk Category

• Ophthalmological procedures, including cataract surgery, are explicitly categorized as minimal bleeding risk with an approximately 0% 30-day major bleeding risk. 1
• These procedures can be safely performed under full-dose anticoagulation, with consideration to hold the DOAC dose only on the day of procedure to avoid peak anticoagulant effects. 1

Low-to-Moderate Risk Considerations for Specific Glaucoma Surgeries

• The classification applies to most routine glaucoma procedures, though specific surgical techniques may modify risk. 2
• Procedures involving scleral manipulation (trabeculectomy and viscocanaloplasty) carry higher bleeding risk compared to other glaucoma procedures. 3
• Some residual anticoagulant effect is acceptable at the time of low-moderate risk procedures. 1, 2

Anticoagulation Management for Patients on Apixaban

For Minimal Risk Glaucoma Procedures

• Continue apixaban without interruption, or at most hold the dose on the day of procedure to avoid peak anticoagulant effects. 1
• No bridging anticoagulation is required. 4

For Low-to-Moderate Risk Glaucoma Procedures (if interruption deemed necessary)

Preprocedural Management:

• Stop apixaban 1 day (24 hours) before surgery for patients with normal renal function (CrCl ≥30 mL/min). 5, 4
• This corresponds to 2-3 drug half-lives, allowing minimal residual anticoagulant effect of approximately 6%. 1, 4
• For patients with moderate renal impairment (CrCl 15-29 mL/min), extend interruption to 36-48 hours. 4

Postprocedural Resumption:

• Resume apixaban 24 hours after surgery once adequate hemostasis is established. 5, 2, 4
• Critical pitfall: Do NOT resume therapeutic-dose anticoagulation within 24 hours postprocedure, as this confers a 20-fold higher risk for major bleeding. 2, 1
• Heparin bridging is NOT recommended for brief DOAC interruption periods. 4

For High Bleeding Risk Glaucoma Procedures (if applicable)

• Stop apixaban 2 days (48 hours) before surgery for patients with normal/mild renal impairment. 5
• This corresponds to 4 half-lives with minimal (6%) residual anticoagulant effect. 5
• For moderate renal impairment, extend discontinuation to 4 days before surgery. 5
• Resume apixaban 48-72 hours postoperatively. 5
• Consider reduced dose for first 2-3 days (apixaban 2.5 mg twice daily) in high thromboembolism risk patients, then advance to full dose. 5

Evidence-Based Bleeding Risk Data

Actual Bleeding Rates in Glaucoma Surgery

• Patients on anticoagulation/antiplatelet therapy have a 10.1% rate of hemorrhagic complications versus 3.7% in controls. 6
• Patients on anticoagulation specifically have a 22.9% hemorrhagic complication rate versus 8.0% for antiplatelet therapy alone. 6
• Patients who continued anticoagulation during surgery had the highest rate at 31.8%. 6
• However, a 2022 prospective study found no significant increase in severe intraoperative bleeding events related to antiplatelet/anticoagulant medication use (OR 1.2,95% CI 0.7-2.2, p=0.54). 3

Risk Factors Beyond Anticoagulation

• Preoperative intraocular pressure elevation significantly increases bleeding risk. 6
• History of deep vein thrombosis or peripheral arterial occlusive disease increases severe bleeding risk. 3
• Type of glaucoma surgery matters: trabeculectomy and viscocanaloplasty (scleral manipulation procedures) carry higher bleeding risk. 3
• Postoperative hypotony, previous ocular surgeries, and race are additional risk factors. 7

Critical Clinical Pitfalls

Do not routinely discontinue anticoagulation for most glaucoma procedures, as the thromboembolic risk from discontinuation substantially exceeds the risk of significant local hemorrhage. 8

Do not use standard coagulation tests (INR, aPTT) to assess residual apixaban effect, as these tests are insensitive to DOACs; anti-Xa activity correlates with apixaban exposure if measurement is needed. 5, 4

Do not resume LMWH bridging within 24 hours after procedures, as this confers a 20-fold increased bleeding risk. 2, 1

Coordinate management with the patient's cardiologist or primary care provider to balance individual thromboembolism risk versus hemorrhage risk. 7