Questions · Quadratus Lumborum Block
11 questions, 0 approved. Approve them one at a time — a quiz shows nothing you have not.
Recall — derived from a kept point
A meta-analysis of eight randomised trials in 564 patients having abdominal surgery compared the quadratus lumborum block with the transversus abdominis plane block. Summarise the pain, opioid and side-effect findings, and state the anatomical reason the quadratus lumborum block would be expected to come out ahead.
Answer: Pain scores favoured the quadratus lumborum block at every time point measured — 2, 4, 6, 12 and 24 hours — 24-hour morphine consumption was lower, and the duration of analgesia was longer. Postoperative nausea and vomiting did not differ between the two. The anatomical rationale usually offered is the site of deposition: the quadratus lumborum block places injectate against the quadratus lumborum muscle, posterior to the transversalis fascia, while the transversus abdominis plane block places it between two muscle layers of the abdominal wall. Say that as background rather than as a finding — this meta-analysis pooled clinical outcomes and made no anatomical measurements, so it cannot show that the difference in deposition is what produced the pain and opioid results.
The pooled effect sizes here are large but rest on eight small trials with differing surgery and technique; treat the direction as better established than the magnitude.
Source claim: Pooling eight randomised trials with 564 patients undergoing abdominal surgery, the quadratus lumborum block gave significantly lower postoperative pain scores at 2, 4, 6, 12 and 24 hours, lower 24-hour morphine consumption and longer duration of analgesia than the transversus abdominis plane block, with no significant difference in postoperative nausea and vomiting.
Liu X et al., Quadratus lumborum block versus transversus abdominis plane block for postoperative analgesia in patients undergoing abdominal surgeries: a systematic review and meta-analysis of randomized controlled trials, BMC Anesthesiol 2020
recall · CA-2 · phrased by llm
A procedure-specific meta-analysis of five randomised trials in 255 patients having inguinal hernia repair compared the quadratus lumborum block with the transversus abdominis plane block. The pooled pain difference was a mean of -0.45 points (95% CI -0.75 to -0.14, p = 0.004) with I-squared of 94%, and there was no difference in 24-hour opioid consumption. Is that a reason to change your block for hernia repair? Justify your answer from the numbers.
Answer: Not on this evidence. Three things in that result argue against changing. The effect size is under half a point on a pain scale, and the review never translates it into a benefit a patient would feel. The I-squared of 94% means the trials disagreed almost completely, so the pooled point estimate is not describing a consistent effect. And the outcome that would corroborate a real analgesic difference — 24-hour opioid consumption — showed no difference at all. The reviewers put their own finding as "QLB may offer superior pain reduction. However, its effect on opioid consumption remains unclear", which is a good deal short of a reason to change technique.
Statistical significance, clinical significance and consistency are three separate questions. This paper answers the first and leaves the other two open, and the review's own conclusion says the effect on opioid consumption remains unclear.
Source claim: Pooling five randomised trials with 255 patients undergoing inguinal hernia repair, the quadratus lumborum block reduced postoperative pain by a mean difference of -0.45 (95% CI -0.75 to -0.14, p = 0.004) with I-squared 94%, there was no difference in 24-hour opioid consumption between quadratus lumborum and transversus abdominis plane blocks, and the authors conclude that the quadratus lumborum block may offer superior pain reduction but that its effect on opioid consumption remains unclear.
Marcolin P et al., Quadratus lumborum block versus transversus abdominis plane block for inguinal hernia repair: A systematic review and meta-analysis with trial sequential analysis, World J Surg 2024
recall · CA-2 · phrased by llm
This meta-analysis found that combining a quadratus lumborum block with a fascia iliaca compartment block ranked highest for reducing total morphine consumption at ___ hours after primary total hip arthroplasty.
Answer: 24
This meta-analysis found that combining a quadratus lumborum block with a fascia iliaca compartment block ranked highest for reducing total morphine consumption at 24 hours after primary total hip arthroplasty.
Regional anaesthesia modalities for primary total hip arthroplasty: a systematic review and component network meta-analysis · PMID 40483183
recall · CA-2 · phrased by derived
This randomized controlled trial found that for posterior lumbar interbody fusion, quadratus lumborum block at lateral supra-arcuate ligament with ___ mL of 0.4% ropivacaine per side reduced PACU stay by 11 minutes and improved 12 h activity pain scores versus erector spinae plane block.
Answer: 20
This randomized controlled trial found that for posterior lumbar interbody fusion, quadratus lumborum block at lateral supra-arcuate ligament with 20 mL of 0.4% ropivacaine per side reduced PACU stay by 11 minutes and improved 12 h activity pain scores versus erector spinae plane block.
Quadratus lumborum block at lateral supra-arcuate ligament versus erector spinae plane block for perioperative analgesia and postoperative recovery in posterior lumbar interbody fusion: a randomized controlled trial · PMID 41168374
recall · CA-2 · phrased by derived
This meta-analysis found that while quadratus lumborum block statistically reduced ___-hour morphine consumption by 4.61 mg in total laparoscopic hysterectomy patients, this reduction was below the 10 mg minimal clinically important difference and did not decrease postoperative nausea and vomiting.
Answer: 24
This meta-analysis found that while quadratus lumborum block statistically reduced 24-hour morphine consumption by 4.61 mg in total laparoscopic hysterectomy patients, this reduction was below the 10 mg minimal clinically important difference and did not decrease postoperative nausea and vomiting.
Quadratus Lumborum Block for Total Laparoscopic Hysterectomy: A Systematic Review and Meta-Analysis · PMID 40154947
recall · CA-2 · phrased by derived
This randomized controlled trial found that for laparoscopic cholecystectomy, ultrasound-guided quadratus lumborum plane block provided significantly lower Numerical Rating Scale pain scores up to ___ hours and required less tramadol compared to external oblique intercostal plane block.
Answer: 24
This randomized controlled trial found that for laparoscopic cholecystectomy, ultrasound-guided quadratus lumborum plane block provided significantly lower Numerical Rating Scale pain scores up to 24 hours and required less tramadol compared to external oblique intercostal plane block.
Comparison of Ultrasound-Guided Quadratus Lumborum Plane Block and External Oblique Intercostal Plane Block for Postoperative Analgesia After Laparoscopic Cholecystectomy: A Two-Center Randomized Controlled Trial · PMID 41155827
recall · CA-2 · phrased by derived
The point with one number taken out. No model wrote any of this: the stem is the sentence you reviewed, minus a digit, and the paper it came from is named beneath it.
Open prompts
How does your plan change if the patient is not optimised?
open · CA-2 · phrased by derived
What is the physiology behind what we just did?
open · CA-2 · phrased by derived
Talk me through the trade-off you made there.
open · CA-2 · phrased by derived
What would make you abandon this plan and do something else?
open · CA-2 · phrased by derived
Questions only — nothing here asserts anything, which is why a model is allowed to phrase them. Where no model was reachable these are the level defaults.