Bloody Tap
Inadvertent puncture of an epidural blood vessel during needle insertion, resulting in blood aspiration through the catheter. Requires catheter repositioning and affects drug absorption.
Full Definition
A bloody tap is a complication of epidural catheter placement where the needle or catheter inadvertently punctures an epidural blood vessel, most commonly the anterior or posterior venous plexus. This results in blood return when aspirating through the catheter and indicates intravascular placement. Bloody taps occur in approximately 3-12% of epidural procedures and are more common in obstetric patients due to increased epidural vascularity during pregnancy. The presence of blood contraindicates injection of local anesthetic due to the risk of systemic toxicity. Management involves withdrawing the catheter slightly and re-aspirating, or complete removal and re-insertion at a different level. A bloody tap may also increase the risk of epidural hematoma, particularly in patients with coagulation abnormalities.
Usage
Usage note: Distinguish from 'wet tap' (accidental dural puncture) - different complications requiring different management.
In Context
- "A bloody tap was encountered at L3-L4, necessitating catheter repositioning before drug administration." — Procedure note
- "The incidence of bloody taps is higher in pregnant patients due to epidural venous engorgement." — Research article