A Retrospective Review of Quadratus Lumborum Block for Analgesia after Minimally Invasive Hysterectomy

Introduction

• Analgesic efficacy of the quadratus lumborum block (QLB) for laparoscopic and robotic surgeries remain controversial [1-5].

• Hypothesis: preoperative bilateral anterior QLB will reduce postoperative opioid consumption and pain severity in minimally invasive hysterectomies (MIH).

 

Methods

• Retrospective analysis of 1,673 patients who underwent robotic or laparoscopic hysterectomies at UAB between Jan. 2, 2019 and Dec. 28, 2023.

• 316 (18.9%) patients received preoperative bilateral QLB with 50-60 mL 0.25% ropivacaine, and remaining 1,357 (81.1%) did not receive the block

• Primary outcome:

o Cumulative 24-hr postoperative MME

• Secondary outcome:

o Cumulative MME at other postoperative time intervals (1, 6, 12, 48 hrs)

o Pain scores at each time interval

o Time to ambulation

o Time to first postoperative opioid

o Incidence of nausea

• Statistical analyses were performed using two-sample t-tests, chi-square tests, and log-rank tests.

 

Results

• QLB group vs No Block group:

↑24-hr postoperative MME (88.17 vs 67.31, p < 0.014)

↑ incidence of nausea (23.73% vs 17.02%, p <0.005)

↑ intraoperative use of ketorolac (20.25% vs 14.89%) and ketamine (32.59% vs 20.61%)

• No significant differences in pain scores at any time point, time to ambulation, and time to first postoperative opioid

Discussion

• Our single-center retrospective review suggests that bilateral anterior QLB may not be effective in decreasing postoperative MME and pain scores in MIH.

• Our results are like recent studies that showed no analgesic benefit in QLB for laparoscopic gynecologic surgery [4-5].

• Limitations of the study:

o Retrospective design

o Block effectiveness was not regularly tested prior to surgery

o Variability in intraoperative analgesics administration

o Differences in block execution due to resident training

o Larger number of patients were in the no block group compared to the QLB group which may reflect our institution’s ERAS protocols and surgeon preferences

Conclusion

• In patients undergoing MIH, adding bilateral QLB to a multimodal analgesia regimen did not reduce postoperative opioid consumption at 24 hours or improve pain scores at any time point.