Pre-Operative Visit for Eye Surgery in Anticoagulated Patients
Direct Recommendation
For most eye surgeries, particularly cataract procedures, continue anticoagulation without interruption, as the risk of thromboembolic complications from stopping anticoagulants far outweighs the minimal bleeding risk associated with modern topical or intracameral anesthesia techniques. 1, 2
Risk Stratification by Procedure Type
Low Bleeding Risk Eye Procedures (Continue Anticoagulation)
- Cataract surgery with topical/intracameral anesthesia: Continue all anticoagulants including warfarin (if INR therapeutic), aspirin, and NOACs 1, 2
- Minor anterior segment procedures: Continue anticoagulation 3, 4
High Bleeding Risk Eye Procedures (Consider Interruption)
- Vitreoretinal surgery with extensive manipulation: May continue warfarin if INR 1.5-3.1, though individualized assessment needed 5
- Oculoplastic surgery with extensive dissection: Consider temporary interruption based on specific procedure 3, 4
- Glaucoma filtration surgery: May require interruption for certain techniques 3, 4
Essential Pre-Operative Assessment Components
1. Medication Documentation
- Identify specific anticoagulant: warfarin, aspirin, rivaroxaban, apixaban, dabigatran, or combination therapy 1
- Document indication for anticoagulation: atrial fibrillation, mechanical heart valve, recent VTE, coronary stents, cerebrovascular disease 1, 5
- Calculate thromboembolic risk: High-risk conditions include mechanical heart valves, recent stroke/TIA (<3 months), recent VTE (<3 months), atrial fibrillation with CHADS2 ≥4 1
2. Laboratory Testing
- Complete blood count: Assess baseline hemoglobin and platelet count 1
- Renal function (creatinine clearance): Calculate using Cockcroft-Gault or MDRD formula—critical for NOAC dosing and clearance 1
- Liver function tests: AST, ALT, bilirubin 1
- INR if on warfarin: Confirm therapeutic range (typically 2.0-3.0) 1, 5
- PT/aPTT baseline: Document coagulation parameters 1
3. Drug Interaction Assessment
- P-glycoprotein inhibitors (for dabigatran): verapamil, amiodarone, ketoconazole, quinidine, clarithromycin—increase bleeding risk 1
- CYP3A4 inhibitors (for rivaroxaban/apixaban): clarithromycin, erythromycin, azole antifungals—increase drug levels 1
- Concomitant antiplatelet agents: Aspirin <100mg increases bleeding risk but was allowed in clinical trials 1
4. Anesthesia Planning
- Strongly prefer topical or intracameral anesthesia over peribulbar/retrobulbar injection for cataract surgery—dramatically reduces bleeding risk even with continued anticoagulation 2, 3, 4
- Avoid needle-based regional blocks in anticoagulated patients when possible 2
Management Algorithm by Anticoagulant Type
Warfarin Management
For cataract surgery: Continue warfarin without interruption if INR is in therapeutic range (typically 2.0-3.0) 1, 2
If interruption required for high-risk procedures:
- Stop warfarin 5 days before surgery (allows 4-5 half-lives for clearance) 1, 6
- Check INR 1 day before surgery to confirm normalization 1
- Resume warfarin 12-24 hours after surgery once hemostasis achieved 1
- Do NOT use bridging anticoagulation for most patients—increases bleeding risk without reducing thrombotic events 1, 7, 8
Aspirin Management
Continue aspirin for all eye procedures including cataract surgery—safe and discontinuation increases thromboembolic risk 1, 2
Novel Oral Anticoagulants (NOACs)
Rivaroxaban (Xarelto)
For low bleeding risk procedures:
- Stop 2 days before surgery (skip 1 dose) if CrCl >50 mL/min 1
- Stop 3 days before surgery (skip 2 doses) if CrCl 15-30 mL/min 1
For high bleeding risk procedures:
- Stop 3 days before surgery (skip 2 doses) if CrCl >50 mL/min 1
- Stop 4 days before surgery (skip 3 doses) if CrCl 15-30 mL/min 1
- Resume 24-48 hours after surgery once hemostasis confirmed 7
Apixaban (Eliquis)
For low bleeding risk procedures:
- Stop 2 days before surgery (skip 2 doses) if CrCl >50 mL/min 1, 8
- Stop 3 days before surgery (skip 4 doses) if CrCl 30-50 mL/min 1, 8
For high bleeding risk procedures:
- Stop 3 days before surgery (skip 4 doses) if CrCl >50 mL/min 1, 8
- Stop 4 days before surgery (skip 6 doses) if CrCl 30-50 mL/min 1, 8
- Resume 24 hours after low-risk surgery, 48-72 hours after high-risk surgery 8, 9
Dabigatran (Pradaxa)
For low bleeding risk procedures:
- Stop 2 days before surgery (skip 2 doses) if CrCl >50 mL/min 1
- Stop 3 days before surgery (skip 4 doses) if CrCl 30-50 mL/min 1
For high bleeding risk procedures:
- Stop 3 days before surgery (skip 4 doses) if CrCl >50 mL/min 1
- Stop 4-5 days before surgery (skip 6-8 doses) if CrCl 30-50 mL/min 1
Critical Pitfalls to Avoid
Never use bridging anticoagulation routinely—increases bleeding risk 3-fold without reducing thrombotic events 1, 7, 8
Never stop aspirin for cataract surgery—the American College of Chest Physicians explicitly recommends continuation 1
Never fail to calculate creatinine clearance for NOAC patients—renal function directly determines drug half-life and required interruption period 1
Never use peribulbar/retrobulbar blocks in anticoagulated patients—topical anesthesia eliminates this bleeding risk 2, 3, 4
Never stop anticoagulation without consulting the prescribing physician—document the thromboembolic risk and obtain clearance for any interruption 3, 4, 5
Never assume NOACs can be managed like warfarin—they have different pharmacokinetics requiring specific timing based on renal function 1
Documentation Requirements
- Anticoagulant type, dose, and indication 1
- Calculated creatinine clearance (not just serum creatinine) 1
- INR if on warfarin 1
- Thromboembolic risk stratification 1
- Planned anesthesia technique 2, 3, 4
- Communication with prescribing physician if interruption considered 3, 4, 5
- Specific timing of last preoperative dose and planned resumption 1, 7, 8