Volume vs Concentration: Quadratus Lumborum Blocks With High Volume/Low Concentration or Low Volume/ High Concentration in Nephrectomies

Volume Versus Concentration: a Prospective, Double Blind, Parallel Study to Compare the Clinical Effectiveness of Bilateral Quadratus Lumborum Blocks Using High Volume/Low Concentration or Low Volume/ High Concentration Local Anesthetic in Nephrectomies

The quadratus lumborum has since 2016 become standard of care for abdominal and retroperitoneal surgeries at UPMC-Shadyside Hospital, replacing paravertebral blocks, and as part of a broader multimodal analgesia institutional Enhanced Recovery After surgery protocol. Since the first description of this technique, several approaches to and anatomic targets within the quadratus lumborum plane have been described although their mechanism of action, spread, and relative clinical effectiveness remain areas of some debate. What is proposed here is to investigate the relative clinical effectiveness of the relationship high volume/low concentration of local anesthetic or low volume/ high concentration of local anesthetic.

Inclusion Criteria:

1. Patients 18-90 years old
2. Patients undergoing nephrectomy
3. Body Mass Index 19-36
4. Male and Female
5. All races
6. American Society of Anesthesiologist scale I, II, III

Exclusion Criteria:

1. Patient refusal
2. Pregnancy
3. Non-English speaking or inability to participate in the study
4. Patients with coagulopathy or With International Normalized Ratio >1,5 the day of the surgery.
5. Chronic steroid use
6. Chronic pain
7. Chronic opiate use