Differential axillary nerve block for hand or forearm soft-tissue surgery.

Area of Science:

• Anesthesiology
• Regional Anesthesia
• Pain Management

Background:

• Axillary brachial plexus block is crucial for forearm and hand surgery.
• Achieving differential block (sensory block with preserved motor function) is key for patient satisfaction and adequate analgesia.
• Determining the optimal ropivacaine concentration is essential for effective differential block.

Purpose of the Study:

• To determine the effective concentration of ropivacaine for sensory block with mobilization via axillary brachial plexus block.
• To evaluate the adequacy of analgesia and patient satisfaction after soft tissue surgery of the forearm or hand.
• To establish the optimal ropivacaine concentration for achieving differential block.

Main Methods:

• Forty-four patients underwent ultrasound-guided axillary nerve block using 16 mL of ropivacaine.
• Postoperative analgesia, sensory/motor function, side effects, and patient satisfaction were assessed 24 hours post-surgery.
• Effective nerve block concentration was calculated using probit analysis.

Main Results:

• Eighteen patients achieved satisfactory differential block, reporting significantly higher satisfaction than those with incomplete block.
• The maximum effective concentration of ropivacaine for differential block was calculated at 0.1285% (using 6 mL).
• This concentration resulted in 71% of patients experiencing both sensory block and maintained motor function.

Conclusions:

• 16 mL of 0.1285% ropivacaine is suitable for achieving differential block.
• Ultrasound-guided axillary nerve block with this concentration provides effective analgesia and preserves motor function for hand and forearm surgery.
• The findings support the use of this specific ropivacaine concentration for optimized patient outcomes.