Bleeding complications with enoxaparin for deep venous thrombosis prophylaxis

Area of Science:

• Orthopedic Surgery
• Pharmacology
• Hematology

Background:

• Deep venous thrombosis prophylaxis is crucial after major orthopedic procedures.
• Enoxaparin, a low-molecular-weight heparin, is widely used for prophylaxis.
• Optimal enoxaparin use and associated bleeding risks require further investigation.

Purpose of the Study:

• To evaluate bleeding complications associated with enoxaparin prophylaxis after total knee, total hip, or hip hemiarthroplasty.
• To identify patient and operative factors influencing bleeding risk with enoxaparin.

Main Methods:

• A case-control study comparing patients receiving enoxaparin prophylaxis with matched controls receiving no pharmacologic anticoagulation.
• Analysis of patient/operative characteristics, hematologic values, and enoxaparin timing related to bleeding.
• Inclusion of 152 enoxaparin cases and 152 control cases.

Main Results:

• Enoxaparin group showed a higher total complication rate (23.7%) versus controls (16.5%), though not statistically significant (P=.11).
• Increased postoperative hematocrit drop (P=.003) and transfusion requirements (P=.02) were observed in the enoxaparin group, particularly after primary single-joint procedures.
• Fewer complications occurred when enoxaparin was initiated 10+ hours postoperatively (P=.05).
• One case of epidural hematoma occurred in a patient receiving enoxaparin with an epidural catheter.

Conclusions:

• While not statistically significant in this underpowered study, enoxaparin was associated with increased postoperative bleeding.
• Delayed enoxaparin administration (≥10 hours postoperatively) and use in primary single-joint replacements may minimize complications.
• Concurrent use of enoxaparin with indwelling epidural catheters is contraindicated due to severe bleeding risk.