Daily Anesthesiology Research Analysis
A multicentre double-blind RCT found that adding raw EEG interpretation to processed EEG did not improve quality of recovery or reduce propofol use. A large US cardiac surgery analysis revealed sex- and race-based disparities in perioperative management for CABG, with transesophageal echocardiography and multimodal analgesia linked to better outcomes. A double-blind RCT optimized superior trunk block dosing, significantly reducing hemidiaphragmatic paralysis while maintaining surgical anesthesia
Summary
A multicentre double-blind RCT found that adding raw EEG interpretation to processed EEG did not improve quality of recovery or reduce propofol use. A large US cardiac surgery analysis revealed sex- and race-based disparities in perioperative management for CABG, with transesophageal echocardiography and multimodal analgesia linked to better outcomes. A double-blind RCT optimized superior trunk block dosing, significantly reducing hemidiaphragmatic paralysis while maintaining surgical anesthesia, albeit with shorter postoperative analgesia.
Research Themes
- Intraoperative brain monitoring and recovery outcomes
- Perioperative equity and practice variation in cardiac anesthesia
- Diaphragm-sparing regional anesthesia optimization
Selected Articles
1. The effect of raw EEG implementation for assessing depth of anaesthesia on patient quality of recovery: A multicentre, double-blind, randomised controlled trial.
In a multicentre, double-blind RCT across four Swiss centres, a brief raw EEG tutorial with intraoperative raw EEG display did not improve QoR-15 on postoperative day 1 or reduce propofol consumption versus standard processed EEG alone. Findings suggest raw EEG interpretation training, as delivered, is insufficient to change recovery endpoints in largely middle-aged laparoscopic cohorts.
Impact: Provides high-quality negative evidence on a widely discussed monitoring strategy, guiding resource allocation and training priorities in depth-of-anaesthesia monitoring.
Clinical Implications: Do not expect improved recovery solely by adding raw EEG interpretation to processed EEG. If adopting raw EEG, consider comprehensive, in-depth training and targeting higher-risk populations or endpoints beyond QoR-15 (e.g., awareness, hypotension, delirium).
Key Findings
- No significant difference in QoR-15 on postoperative day 1 between groups (mean difference -3.2; 95% CI -8.8 to 2.5; P=0.273).
- Propofol consumption was not reduced with raw EEG implementation (mean difference 0.36 mg/kg/h; 95% CI -0.01 to 0.73; P=0.055).
- Matched and randomized 232 practitioner–patient pairs; 209 analyzed; monitoring included raw+processed EEG vs processed EEG alone.
Methodological Strengths
- Multicentre, double-blind randomized controlled design with practitioner–patient pair matching
- Use of validated tutorial and standardized outcomes (QoR-15, propofol consumption)
Limitations
- Predominantly middle-aged, largely female laparoscopic population; limited generalizability to high-risk cohorts
- Brief educational intervention; potential underdosing of training; no long-term cognitive or delirium outcomes
Future Directions: Evaluate comprehensive raw EEG training packages in vulnerable populations (older adults, high anesthetic risk), with endpoints including intraoperative awareness, hypotension burden, postoperative delirium, and longer-term recovery.
BACKGROUND: Processed electroencephalography is widely used to assess depth of anaesthesia and to titrate anaesthetics, thereby increasing the quality of recovery. However, the processed electroencephalogram is influenced by technical, patient, and anaesthetic factors. Adding information from the frontal real-time raw electroencephalogram may help to overcome these limitations. OBJECTIVE: To assess the effect of a raw electroencephalogram tutorial and its intra-operative implementation versus standard care on postoperative quality of recovery and propofol consumption. DESIGN: Multicentre double-blind randomised controlled trial. SETTING: The trial was conducted at four tertiary centres in Switzerland. PATIENTS AND ANAESTHESIA PRACTITIONERS: We screened 534 adult patients undergoing in-hospital laparoscopies and 346 anaesthesia practitioners with at least 2 years of anaesthesia experience. We matched and randomised 232 pairs and analysed 209. The patients were 78% female. INTERVENTION: The anaesthesia practitioners assigned to the patients were randomised to a validated tutorial for assessing depth of anaesthesia with the raw electroencephalogram or to a no tutorial group. Monitoring included raw and processed electroencephalogram for patients allocated to the tutorial and only processed electroencephalogram for the no tutorial group. MAIN OUTCOME MEASURES: The primary outcome was quality of recovery on the first postoperative day measured with the QoR-15 score. The first secondary outcome was propofol consumption. Groups were compared with a two-sample t -test. RESULTS: We found no statistically significant difference between the tutorial and the no tutorial group with mean differences of -3.2 [95% confidence interval (CI), -8.8 to 2.5, P = 0.273] for QoR-15 score and 0.36 mg kg -1 h -1 (95% CI, -0.01 to 0.73, P = 0.055) for propofol consumption. CONCLUSION: A short tutorial on the raw electroencephalogram and its addition intra-operatively was not able to improve quality of recovery or reduce propofol consumption in middle-aged, largely female patients.
2. Variations in perioperative management and outcomes of patents undergoing coronary artery bypass grafting by sex, race, and ethnicity: analysis of a US cardiac surgery database.
Among 40,009 isolated CABG cases, female and Black patients were less likely to receive TOE and multimodal analgesia; Black patients were also less likely to receive PACs. TOE and multimodal analgesia were independently associated with improved outcomes, whereas PAC use and an attending-with-trainee care team were associated with worse outcomes.
Impact: Links practice variation and inequity to clinical outcomes at national scale, identifying modifiable anesthetic practices correlated with benefit or harm.
Clinical Implications: Promote equitable, protocolized use of TOE and multimodal analgesia in CABG and scrutinize indications for PAC use. Develop equity-focused quality metrics and decision support to reduce practice gaps.
Key Findings
- Female (OR 0.86) and Black (OR 0.78; 95% CI 0.71–0.86) patients were less likely to receive TOE.
- Black patients were less likely to receive PACs (OR 0.84; 95% CI 0.73–0.91); both female (OR 0.82) and Black (OR 0.58) patients were less likely to receive multimodal analgesia.
- TOE (OR 0.88) and multimodal analgesia (OR 0.76) were associated with improved outcomes, whereas PAC (OR 1.25) and attending-with-trainee teams (OR 1.30) were associated with worse outcomes.
Methodological Strengths
- Very large, contemporary national cohort from the STS database with multivariable adjustment
- Simultaneous evaluation of practice patterns and outcome associations across multiple modalities
Limitations
- Observational design limits causal inference; residual confounding and selection bias possible
- Practice definitions and indications may vary by site; unmeasured severity or resource factors may influence associations
Future Directions: Prospective, equity-focused implementation studies to standardize TOE and multimodal analgesia use, and randomized or quasi-experimental evaluations of PAC strategies in CABG.
BACKGROUND: Variations in coronary artery bypass graft (CABG) anaesthetic practices and their effects on clinical outcomes according to sex, race, and ethnicity are understudied. METHODS: Patients who underwent isolated CABG in the Society of Thoracic Surgeons Adult Cardiac Surgery Database from July 2017 to December 2023 were included. Multivariable models evaluated (1) the association between key anaesthetic practices (transoesophageal echocardiography [TOE], pulmonary artery catheter [PAC], multimodal analgesia [MMA], acute normovolaemic haemodilution, transfusion algorithm, cerebral oximetry, electroencephalography, and anaesthesia care team) and sex, race, and ethnicity, and (2) the association between anaesthetic practices and postoperative morbidity and mortality. RESULTS: In total, 40 009 patients were included. Female and Black patients were less likely to receive TOE when compared with male (odds ratio [OR] 0.86; P<0.001) and White patients (OR 0.78; 95% confidence interval [CI] 0.71-0.86; P<0.001). Black patients were less likely to receive PACs than White patients (OR 0.84; 95% CI 0.73-0.91; P<0.008). Female and Black patients were less likely to receive MMA when compared with male (OR 0.82; 95% CI 0.71-0.96; P=0.011) and White patients (OR 0.58; 95% CI 0.50-0.68; P<0.001). TOE (OR 0.88; 95% CI 0.78-1.00; P<0.047) and MMA (OR 0.76; 95% CI 0.65-0.88; P<0.001) were independently associated with improved outcomes. PAC (OR 1.25; 95% CI 1.15-1.36; P<0.001) and anaesthesia attending with fellow/resident team (OR 1.30; 95% CI 1.18-1.43; P<0.001) were independently associated with worse outcomes. CONCLUSIONS: There is variability in CABG anaesthetic practices by sex, race, and ethnicity. Future studies should test whether adoption of specific anaesthetic practices in specific populations may impact CABG outcomes.
3. Optimizing the superior trunk block for arthroscopic shoulder surgery: a randomized, double-blind comparison of low- vs. conventional-dose ropivacaine on anesthesia, analgesia, and diaphragmatic function.
In a double-blind RCT of 88 arthroscopic shoulder surgery patients, low-dose ropivacaine (10 mL 0.25%) STB reduced complete/partial hemidiaphragmatic paralysis from 84.1% to 31.8% while maintaining successful surgical anesthesia. Trade-offs included higher 12-hour pain scores and shorter sensory block duration, though overall satisfaction favored the low-dose strategy.
Impact: Defines a diaphragm-sparing dosing strategy that preserves operative anesthesia, informing safer regional anesthesia choices for shoulder surgery.
Clinical Implications: Consider 10 mL of 0.25% ropivacaine for superior trunk block to reduce hemidiaphragmatic paralysis risk. Plan multimodal postoperative analgesia or adjuncts to offset shorter block duration.
Key Findings
- HDP incidence at 3 h was significantly lower with low-dose STB (31.8%) vs conventional dose (84.1%); absolute risk reduction 52.3% (95% CI 34.8–69.8%).
- All patients achieved adequate surgical anesthesia without conversion or intraoperative rescue analgesia.
- Low-dose group had higher pain scores at 12 h and shorter sensory block duration, but higher overall satisfaction.
Methodological Strengths
- Randomized, double-blind design with predefined primary and secondary outcomes
- Direct clinical relevance with objective diaphragm function assessment and patient-centered outcomes
Limitations
- Single-centre, modest sample size; external validity requires confirmation
- Short follow-up; no long-term respiratory or opioid-related outcomes reported
Future Directions: Dose-finding and adjunct studies to extend analgesia while maintaining diaphragm-sparing benefits; evaluate respiratory and functional outcomes and opioid consumption.
BACKGROUND: The superior trunk block (STB) has been proposed as an alternative to interscalene block for reducing the risk of hemidiaphragmatic paralysis (HDP) while maintaining adequate analgesia. However, the optimal local anesthetic dosage for STB has not been established. This study aimed to evaluate whether a low dose of ropivacaine could effectively provide surgical anesthesia, reduce the incidence of complete and partial HDP, and improve anesthetic safety and patient comfort during shoulder arthroscopy. METHODS: Eighty-eight patients scheduled for shoulder arthroscopy were enrolled and randomly allocated in a 1:1 ratio to either a low-dose group (LD group; 10 mL of 0.25% ropivacaine) or a conventional-dose group (CD group; 15 mL of 0.5% ropivacaine). The primary outcome was the incidence of HDP assessed at 3 h post-block. Secondary outcomes included rates of successful surgical anesthesia, pain scores, opioid consumption, duration and onset time of the block, handgrip strength, and patient satisfaction. RESULTS: The incidence of complete and partial HDP at 3 h post-STB was significantly lower in the LD group than in the CD group (31.8% vs. 84.1%, p < 0.001), with an absolute risk reduction of 52.3% (95% CI: 34.8% to 69.8%). All patients in both groups successfully underwent surgery without conversion to general anesthesia with tracheal intubation or requiring supplemental intraoperative analgesia. The overall patient satisfaction score was significantly higher in the LD group compared to the CD group (p = 0.003). However, patients in the LD group reported higher pain scores at 12 h post-block (p = 0.044), exhibited a shorter duration of sensory block (p = 0.001) compared to the CD group. CONCLUSIONS: These findings indicate that a low-dose ropivacaine regimen (10 mL of 0.25%) for STB significantly reduces the incidence of HDP while still providing sufficient surgical anesthesia. However, this approach may be associated with reduced efficacy in postoperative analgesia.