Questions · Erector Spinae Plane Block
11 questions, 0 approved. Approve them one at a time — a quiz shows nothing you have not.
Recall — derived from a kept point
Bilateral ultrasound-guided erector spinae plane blocks were performed at T2 and at T8 in 11 fresh frozen cadavers and the dye spread was dissected. Describe what was found, including the difference between the two levels, and say what it predicts clinically.
Answer: Methylene blue spread variably and extensively deep to the fascia of the erector spinae muscles, but involvement of the spinal rami and the paravertebral space was uncommon and level-dependent: it occurred in 1 of 11 cadavers when injected at T8 and in 4 of 11 at T2, and there was crossover to the contralateral side of the spine. The authors state the clinical implication as a possibility rather than a demonstration: in cadavers the block follows the fascial planes with unpredictable spread, which might explain its varying clinical efficacy. Hold it at that strength — this study dissected dye, not analgesia, so it offers an explanation for variable performance rather than evidence that performance varies.
An injection that follows fascia goes where the fascia allows, not where you intend. Contralateral crossover in a cadaver is also a reminder that a bilateral block is not necessarily two independent blocks.
Source claim: In 11 fresh frozen cadavers receiving bilateral ultrasound-guided erector spinae plane blocks at the second and eighth thoracic vertebrae, methylene blue spread variably and extensively deep to the erector spinae fascia, with involvement of the spinal rami and paravertebral space in 1 of 11 cadavers at the eighth thoracic vertebra and 4 of 11 at the second, including crossover to the contralateral side; the authors conclude that in cadavers the erector spinae plane block follows the fascial planes with unpredictable spread, which might explain its varying clinical efficacy.
Dautzenberg KHW et al., Unpredictable Injectate Spread of the Erector Spinae Plane Block in Human Cadavers, Anesth Analg 2019
recall · CA-2 · phrased by llm
A multicentre, randomised, double-blind trial in 292 women having major oncological breast surgery compared the erector spinae plane block against the thoracic paravertebral block, with the percentage needing morphine in the first two hours as the primary outcome. What did it show, and what should you take from it about substituting the erector spinae plane block for a paravertebral block?
Answer: The erector spinae plane block failed to meet its non-inferiority criterion: 75.2% of the erector spinae plane group needed morphine within two hours against 50.3% of the paravertebral group. Pain scores were higher with the erector spinae plane block, particularly on movement, and the required dermatomal area was not covered in 55.9% of erector spinae plane patients against 20.4% of paravertebral patients. Total morphine consumption and patient satisfaction were similar and no major complications were observed in either arm. The authors' conclusion is that for major breast surgery the thoracic paravertebral block remains the preferred technique. What follows from this trial is that the erector spinae plane block is not an equivalent swap; where it does belong — as a fallback when the paravertebral block is contraindicated or unavailable — is a question the trial did not put to the test.
The dermatomal coverage figure explains the analgesic one. A block that misses the required area in more than half of patients cannot be non-inferior, and this is the anatomical variability of the cadaver studies showing up as a clinical endpoint.
Source claim: In a multicentre randomised double-blind trial of 292 women undergoing major breast surgery, 75.2% of the erector spinae plane block group and 50.3% of the paravertebral block group required morphine within the first two hours, the non-inferiority criterion for the erector spinae plane block was not met, and the required dermatomal area was not covered in 55.9% versus 20.4% of participants respectively; morphine consumption and participant satisfaction were similar between the groups, no major complications were observed, pain scores were greater in the erector spinae plane group especially during mobilisation, and the authors conclude that thoracic paravertebral block remains the preferred technique for major breast surgery.
Raft J et al., Erector spinae plane block versus paravertebral block for major oncological breast surgery: a multicentre randomised controlled trial, Br J Anaesth 2025
recall · CA-2 · phrased by llm
This meta-analysis found that for laparoscopic surgeries, an erector spinae plane block significantly reduces ___-hour postoperative pain scores and opioid consumption compared to a transversus abdominis plane block.
Answer: 24
This meta-analysis found that for laparoscopic surgeries, an erector spinae plane block significantly reduces 24-hour postoperative pain scores and opioid consumption compared to a transversus abdominis plane block.
Erector spinae plane block for laparoscopic surgeries: a systematic review and meta-analysis · PMID 39472781
recall · CA-2 · phrased by derived
This randomized trial found that for patients undergoing uniportal thoracoscopic surgery, surgical intercostal nerve blocks with ___ ml of 0.5% ropivacaine reduced 12-hour morphine consumption and systemic local anesthetic absorption compared to erector spinae plane blocks.
Answer: 30
This randomized trial found that for patients undergoing uniportal thoracoscopic surgery, surgical intercostal nerve blocks with 30 ml of 0.5% ropivacaine reduced 12-hour morphine consumption and systemic local anesthetic absorption compared to erector spinae plane blocks.
Erector Spinae Plane Block versus Intercostal Nerve Blocks in Uniportal Videoscopic-assisted Thoracic Surgery: A Multicenter, Double-blind, Prospective Randomized Placebo-controlled Trial · PMID 40537064
recall · CA-2 · phrased by derived
This randomized controlled trial found that for patients undergoing thoracoscopic lung resection, intercostal nerve block can be used interchangeably with erector spinae plane block for multimodal analgesia, as the ___-hour quality of recovery difference was not significant after Bonferroni correction.
Answer: 24
This randomized controlled trial found that for patients undergoing thoracoscopic lung resection, intercostal nerve block can be used interchangeably with erector spinae plane block for multimodal analgesia, as the 24-hour quality of recovery difference was not significant after Bonferroni correction.
Esketamine vs. placebo combined with erector spinae plane block vs. intercostal nerve block on quality of recovery following thoracoscopic lung resection: a randomized controlled factorial trial · PMID 39172717
recall · CA-2 · phrased by derived
This review identifies erector spinae nerve blocks as one of the commonly performed interventional procedures that, when combined with physical therapy and pharmacologic interventions, can help manage post-mastectomy pain syndrome, which affects 25-___% of breast surgery patients.
Answer: 60
This review identifies erector spinae nerve blocks as one of the commonly performed interventional procedures that, when combined with physical therapy and pharmacologic interventions, can help manage post-mastectomy pain syndrome, which affects 25-60% of breast surgery patients.
Interventional Treatment Options for Post-mastectomy Pain · PMID 37646901
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.