Daily Anesthesiology Research Analysis
Three impactful anesthesiology papers stood out: a consensus-driven core outcome set to standardize airway management research; a two-center randomized trial showing no oxygenation benefit of flow-controlled versus volume-controlled ventilation during one-lung ventilation; and a randomized, double-blind trial demonstrating that low-dose intravenous butorphanol reduces epidural-related maternal fever during labor.
Summary
Three impactful anesthesiology papers stood out: a consensus-driven core outcome set to standardize airway management research; a two-center randomized trial showing no oxygenation benefit of flow-controlled versus volume-controlled ventilation during one-lung ventilation; and a randomized, double-blind trial demonstrating that low-dose intravenous butorphanol reduces epidural-related maternal fever during labor.
Research Themes
- Standardization of outcomes in airway management research
- Ventilation strategies during one-lung ventilation
- Prevention of epidural-related maternal fever in obstetric anesthesia
Selected Articles
1. A core outcome set for airway management research.
Through a systematic review, two-round Delphi surveys across six continents, and consensus panels, the ATOM project defined 11 core outcomes for airway management research and agreed on measurement instruments. The set emphasizes patient safety (e.g., death, cardiac arrest, unrecognized esophageal intubation, hypoxemia) and procedural success without complications, aiming to harmonize future studies.
Impact: Standardized outcomes and definitions will improve comparability and meta-analyses in airway research, accelerating translation into practice. Broad stakeholder engagement enhances generalizability and adoption.
Clinical Implications: Investigators should incorporate the 11 core outcomes and agreed measurement instruments into airway trials and registries to enable robust evidence synthesis and patient-centered evaluation.
Key Findings
- Eleven core outcomes were agreed: death, cardiac arrest, serious complications, pulmonary complications, neurological complications, airway trauma, unrecognised oesophageal intubation, hypoxaemia, first attempt success without complications, overall success without complications, and difficult airway.
- Two-round Delphi surveys included 453 and 155 participants, respectively, from six continents and multiple stakeholder groups.
- Outcome measurement instruments with definitions were proposed and agreed for all included outcomes.
Methodological Strengths
- Systematic review to generate a comprehensive longlist of candidate outcomes
- Multistakeholder, international modified Delphi process with consensus panels
Limitations
- Consensus-based framework without prospective validation of impact on trial conduct or outcomes
- Potential selection bias in Delphi participation and underrepresentation of some regions
Future Directions: Prospective adoption in clinical trials with reporting audits, validation of feasibility and sensitivity to change, and periodic updates to incorporate emerging outcomes.
INTRODUCTION: Airway management research has historically incorporated heterogeneous outcome selection and definitions. This impedes evidence synthesis and hinders advances in patient care. We aimed to develop a core outcome set to standardise airway management research and improve outcome reporting. METHODS: We performed a systematic review of outcomes reported in airway management studies to identify candidate outcomes from a random sample of eligible studies. We used a modified Delphi survey of three key st
2. Efficacy of Intravenous Butorphanol for Preventing Epidural-Related Maternal Fever (ERMF) During Epidural Labor Analgesia: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.
In a randomized, double-blind trial of 424 parturients receiving epidural labor analgesia, a single 1 mg intravenous dose of butorphanol at epidural initiation reduced the incidence of maternal fever compared with placebo (37.3% vs 48.6%). This identifies a pragmatic, pharmacologic prevention strategy for epidural-related maternal fever.
Impact: ERMF contributes to maternal discomfort, antibiotic use, and neonatal sepsis workups; a simple single-dose intervention could reduce this burden.
Clinical Implications: Consider a 1 mg IV butorphanol dose at epidural initiation for laboring patients at institutions adopting ERMF prevention protocols, while monitoring for sedative or neonatal effects in future implementations.
Key Findings
- Randomized, double-blind, placebo-controlled design with 424 women undergoing epidural labor analgesia.
- Butorphanol 1 mg IV at epidural onset reduced maternal fever incidence versus control (37.3% vs 48.6%).
- Demonstrates a feasible pharmacologic strategy to prevent epidural-related maternal fever.
Methodological Strengths
- Randomized, double-blind, placebo-controlled design
- Adequate sample size with balanced allocation (212 vs 212)
Limitations
- Abstract does not report detailed safety, neonatal outcomes, or exact statistical estimates (p-values and effect sizes)
- Single-dose, single-timepoint intervention; generalizability to different populations/settings requires confirmation
Future Directions: Confirmatory multicenter trials with predefined neonatal endpoints, safety profiling, and subgroup analyses (e.g., duration of labor, epidural dose) to inform guideline adoption.
PURPOSE: The purpose of this research was to investigate whether intravenous low dose of butorphanol (1mg) at the onset of epidural analgesia (EA) can reduce the incidence of ERMF during labor. PATIENTS AND METHODS: Four hundred and twenty-four women, aged 18 to 40 years, BMI <=30 kg/m RESULTS: A total of 424 subjects (212 subjects in Butor group and 212 subjects in Con group) were included in the final analysis. There was a significant decrease for the incidence of maternal fever in Butor group compared to Con group (37.3% versus 48.6%, CONCLUSION: A low dose of butorphanol intravenously used at the onset of EA in women undergoing vaginal delivery could effectively reduce the incidence of ERMF. Butorphanol may serve as a potential intervention for preventing ERMF in future.
3. Comparative effects of flow- versus volume-controlled one-lung ventilation on gas exchange and respiratory system mechanics in thoracic surgery: A randomised controlled clinical trial.
In 78 thoracic surgery patients randomized to FCV or VCV during one-lung ventilation, PaO2 at 20 minutes did not differ between groups, while mechanical power was lower with FCV. There were no differences in hypoxemia/hypercapnia rescue needs, postoperative complications, or 30-day hospital-free days.
Impact: This RCT tempers enthusiasm for FCV during OLV by showing no oxygenation or outcome advantages over standard VCV, informing ventilation strategy choices and equipment adoption.
Clinical Implications: VCV remains an appropriate default during OLV; FCV may reduce mechanical power but without demonstrated clinical benefits under FiO2 1.0 and standardized settings.
Key Findings
- Primary endpoint (PaO2 at 20 minutes of OLV) showed no difference between FCV and VCV (24.8 ± 14.8 vs 26.1 ± 15.9 kPa; P = 0.721).
- Mechanical power was lower during FCV compared with VCV.
- No differences in rescue maneuvers for hypoxemia/hypercapnia, postoperative complications, or hospital-free days at day 30.
Methodological Strengths
- Randomized, controlled, two-center design with predefined primary outcome
- Standardized ventilatory settings and perioperative management across groups
Limitations
- Use of FiO2 1.0 may mask oxygenation differences; limited generalizability to different FiO2 strategies
- Sample size powered for oxygenation endpoint, not rare clinical outcomes
Future Directions: Evaluate FCV versus VCV under lung-protective FiO2 strategies, different PEEP/VT titrations, and assess patient-centered pulmonary outcomes (e.g., PPCs) in adequately powered multicenter trials.
BACKGROUND: The effect of flow-controlled ventilation (FCV) as compared with volume-controlled ventilation (VCV) on oxygenation and respiratory system mechanics in patients undergoing one-lung ventilation (OLV) is unknown. OBJECTIVE: To test the hypothesis that FCV would improve oxygenation and respiratory system mechanics compared with VCV during OLV. DESIGN: Two-centre, two-arm, randomised controlled clinical trial. SETTING: University hospital and speciality hospital for pulmonary diseases in Germany. PATIENTS: