Epinephrine Test Dose
Small amount of epinephrine-containing local anesthetic used to detect intravascular injection during epidural catheter placement.
Full Definition
A safety technique involving the injection of a small volume (typically 3-5 mL) of local anesthetic containing epinephrine (usually 1:200,000 or 15 mcg) through an epidural catheter to detect inadvertent intravascular placement. If the catheter tip is positioned within a blood vessel, the epinephrine will cause a transient increase in heart rate (typically >20 beats per minute) and blood pressure within 45-90 seconds. This test is particularly important in obstetric patients due to the engorged epidural venous plexus during pregnancy, which increases the risk of intravascular catheter placement. A positive test indicates the need for catheter repositioning to prevent systemic local anesthetic toxicity.
Usage
Usage note: Should document both the dose of epinephrine used and the patient's hemodynamic response.
In Context
- "The epinephrine test dose produced a heart rate increase to 110 bpm, suggesting intravascular catheter placement." — Anesthetic record
- "A negative epinephrine test dose confirmed proper epidural catheter positioning before proceeding with the block." — Labor analgesia note