Will the Real Benefits of Single-Shot Interscalene Block Please Stand Up? A Systematic Review and Meta-Analysis
Bibliographic record
Abstract
BACKGROUND: Interscalene block (ISB) can provide pain relief after shoulder surgery, but a reliable quantification of its analgesic benefits is lacking. This meta-analysis examines the effect of single-shot ISB on analgesic outcomes during the first 48 hours after shoulder surgery. METHODS: We retrieved randomized and quasirandomized controlled trials examining the analgesic benefits of ISB compared with none in shoulder surgery. Severity of postoperative pain measured on a visual analog scale (10 cm scale, 0 = no pain, 10 = worst pain) at rest at 24 hours was the designated primary outcome. Secondary outcomes included pain severity at rest and with motion at 2, 4, 6, 8, 12, 16, 32, 36, 40, and 48 hours postoperatively. Opioid consumption, postoperative nausea and vomiting, patient satisfaction with pain relief, and postanesthesia care unit and hospital discharge time were also assessed. RESULTS: A total of 23 randomized controlled trials, including 1090 patients, were analyzed. Patients in the ISB group had more severe postoperative pain at rest by a weighed mean difference (95% confidence interval) of 0.96 cm (0.08-1.83; P = 0.03) at 24 hours compared with no ISB, but there was no difference in pain severity beyond that point. The duration of pain relief at rest and with motion after ISB were 8 and 6 hours, respectively, with a corresponding weighed mean difference in visual analog scale pain scores (99% confidence interval) of -1.59 cm (-2.60 to -0.58) and -2.20 cm (-4.34 to -0.06), respectively, with no additional pain relief benefits beyond these points. ISB reduced postoperative opioid consumption up to 12 hours, decreased postoperative nausea and vomiting at 24 hours, and expedited postanesthesia care unit and hospital discharge. The type, dose, and volume of local anesthetic used did not affect the results. CONCLUSIONS: ISB can provide effective analgesia up to 6 hours with motion and 8 hours at rest after shoulder surgery, with no demonstrable benefits thereafter. Patients who receive an ISB can suffer rebound pain at 24 hours but later experience similar pain severity compared with those who do not receive an ISB. ISB can also provide an opioid-sparing effect and reduce opioid-related side effects in the first 12 and 24 hours postoperatively, respectively. These findings are useful to inform preoperative risk-benefit discussions regarding ISB for shoulder surgery.
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 | 0.023 | 0.055 |
| Meta-epidemiology (narrow) | 0.002 | 0.002 |
| Meta-epidemiology (broad) | 0.022 | 0.040 |
| Bibliometrics | 0.005 | 0.005 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.004 | 0.003 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.003 | 0.002 |
| Insufficient payload (model declined to judge) | 0.006 | 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".