Weekly ReportOct 12–18, 2026
Anesthesiology, week 42 edition
We read 299 papers and selected 3.
Summary
This week’s anesthesiology literature emphasized precision monitoring, opioid-sparing regional anesthesia, and safer individualized perioperative care. Randomized data refined interpretation of the Bispectral Index across volatile anesthetics, while a methodological EEG study showed that preprocessing order can create irreversible functional-connectivity artifacts in anesthesia-relevant signals. Regional techniques continued to expand, including phrenic nerve-sparing shoulder field anesthesia and cardiac-surgery blocks, while prediction models, prehospital GFAP testing, early oral intake, sustainable anesthesia, and pediatric neuromuscular reversal highlighted broader clinical and health-system innovation.
Selected Articles
1. Characterization of the Bispectral Index in Healthy Volunteers Receiving Inhalation Anesthetics in Combination With Opioids in a Randomized Trial.
This randomized trial of 211 healthy volunteers evaluated BIS and responsiveness across sevoflurane, desflurane, and isoflurane regimens, with selected opioid combinations. BIS predicted responsiveness with an AUROC of at least 0.95, but BIS50 and BIS95 thresholds varied across agents. Opioids added to sevoflurane had minimal influence, whereas desflurane produced somewhat lower BIS thresholds.
Impact: The study provides rigorous calibration data for a widely used anesthesia monitor and demonstrates that a single BIS target does not represent an identical clinical state across volatile anesthetics. This directly supports agent-aware interpretation of processed EEG monitoring.
Clinical Implications: BIS is useful for assessing responsiveness during volatile anesthesia, but thresholds should be interpreted in the context of the specific anesthetic agent and clinical setting. These volunteer data should not be directly transferred to older, medically complex, or surgically stimulated patients.
Key Findings
- BIS50 ranged from 67.5 to 76.2 and BIS95 ranged from 49.1 to 63.3 across anesthetic regimens.
- BIS predicted responsiveness with AUROC values of at least 0.95.
- Adding remifentanil or fentanyl to sevoflurane had minimal impact, while desflurane was associated with lower BIS thresholds.
2. Irreversible functional network deformation induced by preprocessing scheme order in multivariate EEG recordings.
This methodological study used human sleep EEG, synthetic signals, and surrogate-based testing to show that re-referencing before filtering can generate spurious cross-correlations in multivariate EEG. The distortion was strongest and potentially irreversible in signals with steep power spectra, including slow-wave sleep and anesthesia-related states. Filtering followed by re-referencing with surrogate correction was recommended.
Impact: The paper identifies a systematic and underappreciated source of bias that can alter functional-connectivity conclusions in anesthesia, sleep, epilepsy, and disorders of consciousness. It offers an immediately actionable reproducibility standard and may require reanalysis of existing datasets.
Clinical Implications: EEG studies used for anesthesia depth, emergence, epilepsy monitoring, or disorders of consciousness should prespecify preprocessing order and apply appropriate surrogate correction. Existing connectivity-based biomarkers should be interpreted cautiously until their preprocessing pipelines are verified.
Key Findings
- Re-referencing followed by filtering produced spurious cross-correlations that increased with frequency band and depended on the power spectral exponent.
- For signals with power spectral exponent β ≥2, artificial correlations were reported to be irreversible.
- Filtering followed by re-referencing with surrogate correction was recommended for multivariate signals with β ≥2.
3. Comparison of Shoulder Field Anesthesia (SFA) with Interscalene Block (ISB) for Analgesia After Arthroscopic Shoulder Surgery: A Randomized Noninferiority Trial.
In this randomized trial of 80 patients, surgeon-performed shoulder field anesthesia was noninferior to interscalene block for cumulative 48-hour pain. Interscalene block provided better analgesia at 4–8 hours, but opioid use and satisfaction were similar, while shoulder field anesthesia had shorter hospital stay and no observed respiratory or Horner syndrome events.
Impact: The trial provides Level I evidence for a phrenic nerve-sparing alternative to a standard shoulder block. It directly addresses respiratory risk while preserving overall analgesic effectiveness, supporting more individualized regional anesthesia selection.
Clinical Implications: Shoulder field anesthesia may be considered for patients in whom phrenic nerve dysfunction or hemidiaphragmatic paralysis would pose substantial risk, particularly those with limited pulmonary reserve. Interscalene block may remain preferable when maximal early analgesia is the priority.
Key Findings
- Shoulder field anesthesia was noninferior to interscalene block for cumulative 48-hour pain.
- Cumulative opioid consumption and patient satisfaction were similar between groups.
- Horner syndrome and respiratory events occurred only in the interscalene group, although the study was underpowered for uncommon complications.