Transmuscular quadratus lumborum block for percutaneous nephrolithotomy: Study protocol for a dose-finding trial

Area of Science:

• Anesthesiology
• Regional Anesthesia
• Pain Management

Background:

• Percutaneous nephrolithotomy (PNL) is a surgical procedure for kidney stones.
• Effective postoperative pain control is crucial for PNL patients.
• The transmuscular quadratus lumborum (TQL) block is an emerging regional anesthesia technique.

Purpose of the Study:

• To determine the minimal effective volume (MEV90) of 0.75% ropivacaine for a single-shot TQL block.
• To optimize the TQL block for pain management in PNL patients.
• To establish evidence-based dosing for TQL blocks in this specific surgical context.

Main Methods:

• A double-blind, randomized, controlled dose-finding trial using a biased coin up-and-down design.
• Sequential administration of ropivacaine volumes based on previous patient responses.
• Block success defined by Numeric Rating Scale (NRS) pain score ≤3 in the post-anesthesia care unit (PACU).
• A minimum of 25 patients required for precise MEV90 estimation with bootstrapping.

Main Results:

• The study aims to identify the MEV90 of ropivacaine for TQL block.
• Data analysis will be performed, with results intended for publication.
• The precise MEV90 will be derived using bootstrapping methods.

Conclusions:

• The findings will provide crucial data on optimal ropivacaine volume for TQL blocks.
• This research will contribute to improved pain management strategies for PNL.
• The study seeks to establish a standardized and effective anesthetic protocol for TQL blocks.