Daily Anesthesiology Research Analysis
Three practice-informing studies stood out in anesthesiology and critical care. A large stepped-wedge cluster RCT showed that targeting normoxemia (SpO2 90–96%) in trauma ICU patients safely reduced hyperoxemia and sped weaning to room air without increasing hypoxemia. An ICU randomized trial found a flexible-tip bougie markedly improved first-attempt success for tracheal intubation with a hyperangulated videolaryngoscope versus a stylet. A multicenter cohort linked higher early mechanical power
Summary
Three practice-informing studies stood out in anesthesiology and critical care. A large stepped-wedge cluster RCT showed that targeting normoxemia (SpO2 90–96%) in trauma ICU patients safely reduced hyperoxemia and sped weaning to room air without increasing hypoxemia. An ICU randomized trial found a flexible-tip bougie markedly improved first-attempt success for tracheal intubation with a hyperangulated videolaryngoscope versus a stylet. A multicenter cohort linked higher early mechanical power during ventilation to higher ICU mortality in acute hypoxemic respiratory failure, with no safe threshold.
Research Themes
- Oxygen stewardship and normoxemia targeting in critical care
- Airway device optimization for ICU videolaryngoscopy
- Ventilator-induced lung injury metrics (mechanical power) and outcomes
Selected Articles
1. Targeted Normoxemia and Supplemental Oxygen-Free Days in Critically Injured Adults: A Stepped-Wedge Cluster Randomized Clinical Trial.
In this multicenter stepped-wedge cluster RCT (N=12,487), targeting SpO2 90–96% increased time in normoxemia, reduced hyperoxemia, and did not increase hypoxemia. Although supplemental oxygen–free days were not improved overall, time to room air was shorter and a prespecified subgroup (not ventilated at ICU admission) had slightly more oxygen-free days.
Impact: This pragmatic trial provides high-level evidence to guide oxygen stewardship in the ICU, showing clinicians can safely reduce hyperoxemia by targeting normoxemia without increasing hypoxemia.
Clinical Implications: Adopt SpO2 targets of 90–96% for critically injured adults to reduce hyperoxemia and expedite weaning to room air, with monitoring to avoid hypoxemia. Expect neutral effect on overall oxygen-free days but process-of-care gains.
Key Findings
- Normoxemia time increased from 56.2% to 71.6%; hyperoxemia decreased from 42.4% to 26.7%; hypoxemia remained 1.1% in both groups.
- No overall increase in supplemental oxygen–free days (adjusted mean difference 0.32 days; 95% CI -0.37 to 1.00; P=0.30).
- Faster weaning to room air (adjusted hazard ratio 1.23; 95% CI 1.13–1.33) without safety signal; mortality to day 90 similar.
- Among patients not ventilated at ICU admission, oxygen-free days modestly improved (AMD 0.75 days; 95% CI 0.00–1.50).
Methodological Strengths
- Multicenter stepped-wedge cluster randomized design with intention-to-treat analysis
- Large sample size (N=12,487) and pragmatic, process-integrated intervention
Limitations
- Primary outcome was neutral overall; potential contamination and secular trends inherent to stepped-wedge designs
- Unblinded process intervention; conducted in US level I trauma centers, potentially limiting generalizability
Future Directions: Test normoxemia-targeting bundles in broader ICU populations, assess patient-centered outcomes and cost-effectiveness, and integrate automated closed-loop oxygen control.
2. Flexible-tip bougie vs. stylet for tracheal intubation with a hyperangulated videolaryngoscope in critical care: a randomised controlled trial.
In ICU intubations using a hyperangulated videolaryngoscope, a flexible-tip bougie achieved a 99% first-attempt success rate versus 83% with a stylet, with less need for laryngeal manipulation and no increase in complications.
Impact: Clear, clinically meaningful improvement in first-pass success supports changing default introducer choice for hyperangulated videolaryngoscopy in critical care.
Clinical Implications: Prefer a flexible-tip bougie rather than a stylet when using hyperangulated videolaryngoscopes in ICU to maximize first-pass success and minimize adjunct maneuvers.
Key Findings
- First-attempt success: 99% (flexible-tip bougie) vs 83% (stylet), P=0.005.
- Fewer laryngeal manipulations with bougie: 10% vs 31.4%.
- No significant difference in complication rates between techniques.
- Operator-rated difficulty favored bougie (not difficult/slightly difficult in 99% vs 90%).
Methodological Strengths
- Randomized controlled design with clinically relevant ICU population
- Clear, objective primary endpoint (first-attempt success) and standardized device context (hyperangulated blade)
Limitations
- Single-center trial and lack of blinding of operators
- Results limited to hyperangulated videolaryngoscopes; generalizability to standard blades uncertain
Future Directions: Validate findings across multiple centers, operator experience levels, and different hyperangulated platforms; assess effects on hypoxemia and hemodynamic instability.
3. The Association Between Mechanical Power Within the First 24 Hours and ICU Mortality in Mechanically Ventilated Adult Patients With Acute Hypoxemic Respiratory Failure: A Registry-Based Cohort Study.
Across 9,031 mechanically ventilated adults with acute hypoxemic respiratory failure, higher mechanical power within the first 24 hours was independently associated with higher ICU mortality (OR 1.58), fewer ventilator-free days, and lower extubation rates, with no safe threshold identified.
Impact: Mechanical power is a synthesizing metric of injurious ventilation. Quantifying its association with mortality in a broad AHRF cohort supports MP minimization as a target for future interventional trials.
Clinical Implications: Consider incorporating mechanical power into bedside ventilator management and aim to minimize MP early (e.g., by optimizing VT, RR, Pplat/PEEP) alongside conventional lung-protective strategies.
Key Findings
- High mechanical power (>17 J/min) in the first 24 hours was associated with higher ICU mortality (adjusted OR 1.58; 95% CI 1.44–1.72).
- Nonlinear dose-response relationship observed; no consistent safe threshold of mechanical power identified.
- High MP was linked to lower extubation rates and fewer ventilator-free days.
Methodological Strengths
- Large multicenter registry with 9,031 eligible AHRF patients and robust adjustment (IPTW, spline models)
- Predefined exposure window (first 24 hours) aligning with actionable ventilator management
Limitations
- Observational design with residual confounding; mechanical power components may reflect severity and clinician choices
- Modeling relies on dynamic driving pressure; generalizability to all ventilator modes requires caution
Future Directions: Randomized trials testing mechanical power–targeted ventilation strategies and evaluating causal effects on mortality and VILI biomarkers.