Ultrasound-guided Sciatic Nerve Block in Overweight and Obese Patients
Bibliographic record
Abstract
BACKGROUND AND OBJECTIVES: Despite ultrasound (US) guidance, sciatic nerve block (SNB) remains among the least performed peripheral blocks. By targeting the tissue plane between the gluteus maximus and quadratus femoris muscles, the US-guided subgluteal space technique may facilitate the performance of US-guided SNB. We aimed to evaluate whether the subgluteal space technique shortens SNB performance time in overweight and obese patients compared with the conventional infragluteal technique. METHODS: Overweight and obese patients (body mass index, > 25 kg m ) undergoing US-guided SNB for knee arthroplasty received 30 mL admixture (1:2 lidocaine 2%; bupivacaine 0.5% with 1:200,000 epinephrine) in the tissue plane between the gluteus maximus and quadratus femoris (subgluteal space group) or around the sciatic nerve at the infragluteal level (infragluteal group). All patients received spinal anesthesia, continuous femoral nerve block, and postoperative multimodal analgesia. The primary outcome was SNB performance time defined as the time interval between placement of the US transducer on skin, and needle withdrawal after injection. Number of needle passes, procedural pain, SNB-related complications, SNB success, postoperative pain, and opioid consumption were also assessed. RESULTS: Twenty-seven patients were assessed (subgluteal space, 14; infragluteal, 13). Mean SNB performance time was 4.4 minutes (95% confidence interval, 3.7-5.0) for the subgluteal space group and 9.0 minutes (95% confidence interval, 7.7-10.3) for the infragluteal group (P < 0.0001). Number of needle passes and procedural pain scores were lower in the subgluteal space group. There were no differences in SNB success or analgesic outcomes. CONCLUSIONS: The subgluteal space technique may be performed 50% faster, with no detectable differences in block success and analgesic efficacy, compared with the infragluteal technique for US-guided SNB in overweight and obese patients receiving multimodal analgesia. Injection of local anesthetics along tissue planes may produce similar block characteristics to perineural injection for US-guided SNB.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".