Back pain after epidural anesthesia with chloroprocaine

Area of Science:

• Anesthesiology
• Pain Management
• Pharmacology

Background:

• Chloroprocaine use in epidural anesthesia is associated with severe back pain.
• Potential contributing factors include EDTA preservative, large anesthetic volumes, low pH, and local infiltration.

Purpose of the Study:

• To investigate the relationship between chloroprocaine characteristics and post-epidural anesthesia back pain.
• To compare the incidence and severity of back pain across different chloroprocaine formulations and volumes versus lidocaine.

Main Methods:

• A randomized study involving 100 outpatients undergoing knee surgery with continuous epidural anesthesia.
• Patients received one of five local anesthetics: lidocaine control, chloroprocaine with EDTA, higher volume chloroprocaine, chloroprocaine without EDTA, or pH-adjusted chloroprocaine.
• Pain was assessed using visual analog and verbal analog scales post-anesthesia and via telephone interview at 24 hours.

Main Results:

• Two types of back pain were identified: superficial (Type 1) and deep, aching, burning lumbar pain (Type 2).
• Type 2 pain incidence was significantly higher in the group receiving 30 ml of chloroprocaine (Group III) compared to lidocaine and other chloroprocaine groups.
• Group III also reported significantly higher overall pain scores.

Conclusions:

• Large doses (≥40 ml) of chloroprocaine containing EDTA are associated with a higher incidence of deep, burning lumbar back pain.
• Using 25 ml or less of chloroprocaine resulted in back pain incidence comparable to the lidocaine control group.