Daily Anesthesiology Research Analysis
Translational work identifies methylglyoxal-driven endothelial barrier failure as a causal driver of capillary leak and mortality in sepsis and shows the dipeptide anserine mitigates these effects in vivo. A cohort study links shorter apnea intervals during tracheal intubation in out-of-hospital cardiac arrest to markedly better survival. A pediatric dose-finding trial estimates age-stratified remimazolam doses for reliable loss of consciousness during induction.
Summary
Translational work identifies methylglyoxal-driven endothelial barrier failure as a causal driver of capillary leak and mortality in sepsis and shows the dipeptide anserine mitigates these effects in vivo. A cohort study links shorter apnea intervals during tracheal intubation in out-of-hospital cardiac arrest to markedly better survival. A pediatric dose-finding trial estimates age-stratified remimazolam doses for reliable loss of consciousness during induction.
Research Themes
- Translational sepsis therapeutics targeting endothelial barrier dysfunction
- Airway management quality metrics in cardiac arrest
- Pediatric anesthetic pharmacodynamics for remimazolam
Selected Articles
1. Anserine reduces mortality in experimental sepsis by preventing methylglyoxal-induced capillary leakage.
Using clinical data analyses, animal models, and mechanistic in vitro assays, the study shows methylglyoxal drives endothelial barrier failure and capillary leak in sepsis via RAGE–MAPK signaling. The dipeptide anserine scavenges methylglyoxal, preserves junctional integrity, reduces capillary leakage, and lowers mortality in vivo.
Impact: Identifies a causal, druggable pathway of sepsis-induced capillary leak and provides preclinical efficacy for anserine, motivating rapid translational work. This mechanistic insight could shift sepsis therapy toward endothelial barrier protection.
Clinical Implications: If validated in humans, anserine or other methylglyoxal-scavenging strategies could reduce vasopressor/fluids needs and improve survival in septic shock by stabilizing the endothelial barrier.
Key Findings
- Methylglyoxal independently associated with 48-hour mortality and higher catecholamine/fluids in early sepsis.
- Carbonyl stress disrupted endothelial junctional proteins causing capillary leak in murine sepsis models.
- RAGE–MAPK signaling mediated the detrimental effects of methylglyoxal.
- Anserine reduced AGE formation, preserved junctional complexes in vitro, and decreased capillary leakage and mortality in vivo.
Methodological Strengths
- Translational design linking human observational data with in vivo and in vitro mechanistic validation.
- Multipronged assays (TEER, FACS, cytokines, gene and enzyme analyses, immunostaining) supporting reproducibility.
Limitations
- Preclinical efficacy; no randomized human interventional data yet.
- Exact human sample sizes and selection from the secondary analyses are not detailed in the abstract.
Future Directions: Conduct early-phase clinical trials testing anserine or similar scavengers in septic shock with endothelial leak biomarkers to validate efficacy and dosing.
BACKGROUND: We previously identified methylglyoxal as a biomarker for early identification and outcome prediction in human sepsis. We hypothesised that methylglyoxal causally impacts disease severity, and the methylglyoxal-scavenging dipeptide anserine can attenuate the detrimental effects of methylglyoxal. METHODS: Using a translational approach, secondary analyses of two observational trials were performed to test the initial hypotheses. Afterwards, these results were re-evaluated in different murine models of experimental sepsis in vivo. The detrimental effects of methylglyoxal as well as the underlying mechanisms were further assessed in vitro using transendothelial electrical resistance measurements, fluorescence-activated cell sorting analyses, cytokine assays, gene expression analyses, and enzyme activity assays, as well as immunofluorescence and immunohistochemistry staining. FINDINGS: The secondary analyses confirmed methylglyoxal as an independent marker associated with increased mortality within the first 48 h after sepsis onset and high catecholamine and fluid requirements in the first 24 h after sepsis onset. In the sepsis models, methylglyoxal-derived carbonyl stress significantly contributed to the development of capillary leakage by disrupting endothelial barrier-forming proteins. Mechanistically, a pathway involving the receptor of advanced glycation end products and mitogen-activated protein kinase was identified. The methylglyoxal-scavenging dipeptide anserine (β-alanyl-N-methylhistidine) reduced methylglyoxal-induced advanced glycation end-product formation and disruptions of junctional complexes in vitro. Moreover, anserine reduced capillary leakage and mortality in vivo. INTERPRETATION: Methylglyoxal causally contributes to capillary leak formation and mortality in experimental sepsis, which can be mitigated by anserine. Therefore, anserine represents an innovative therapeutic option for the treatment of septic shock. FUNDING: German Research Foundation (grant number BR 4144/2-1).
2. ED50 and ED95 of remimazolam for loss of consciousness in young children: a dose-finding study for induction of anaesthesia.
In a 120-child, age-stratified dose-finding study using a biased-coin up-and-down design, the investigators estimated ED50/ED95 for remimazolam to induce loss of consciousness. Results support single-bolus induction dosing around 0.45–0.60 mg/kg across pediatric age groups, with predefined monitoring of hemodynamic and respiratory safety.
Impact: Provides practical, age-stratified dosing guidance for a new ultra-short-acting benzodiazepine in pediatric induction, addressing a key evidence gap.
Clinical Implications: Supports adopting approximately 0.45–0.60 mg/kg remimazolam as a starting bolus for pediatric induction, with vigilant monitoring for hypotension and respiratory depression.
Key Findings
- Biased-coin up-and-down design in 120 children (1–12 years) estimated ED50/ED95 for remimazolam-induced loss of consciousness.
- Findings support single-bolus induction dosing around 0.45–0.60 mg/kg across pediatric age groups.
- Secondary outcomes included predefined surveillance for hypotension, respiratory depression, and adverse events.
Methodological Strengths
- Prospective, age-stratified dose-finding with a biased-coin up-and-down method appropriate to estimate ED50/ED95.
- Trial registered (NCT06061159), enhancing transparency.
Limitations
- Abstract truncation limits visibility of precise ED50/ED95 values and safety event rates.
- Single-bolus pharmacodynamics assessed; maintenance dosing and recovery profiles not addressed.
Future Directions: Confirm ED50/ED95 in multicenter settings, define maintenance strategies and recovery profiles, and compare against standard agents in randomized trials.
BACKGROUND: The optimal single i.v. bolus dose of remimazolam for induction of general anaesthesia in children is not defined. We aimed to determine the 50% (ED50) and 95% (ED95) effective doses of remimazolam for inducing loss of consciousness in children. METHODS: A total of 120 children, aged 1-12 yr, were divided into three groups, with 40 children in each group: toddler (1 to <3 yr), preschool (≥3 to <6 yr), and school-age group (≥6 to <12 yr). Each child received a single i.v. bolus of remimazolam, with doses determined using a biased coin design up-and-down method. The primary outcome was the ED50 and ED95 of remimazolam for inducing loss of consciousness. Secondary outcomes included the incidence of hypotension, respiratory depression, and adverse events. RESULTS: The ED50 and ED95 of remimazolam were 0.42 mg kg CONCLUSIONS: A single i.v. bolus of remimazolam at estimated doses of 0.45-0.60 mg kg CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT06061159).
3. The apnea interval: Ventilation interruption during tracheal intubation and its association with cardiac arrest resuscitation care and outcome.
In 254 VF-OHCA cases, the median apnea interval during attempted intubation was 84 seconds, and intervals ≤60 seconds independently correlated with higher ROSC, survival to discharge, and favorable neurologic survival despite high chest compression fractions. The apnea interval emerges as a modifiable quality metric during airway management.
Impact: Defines a simple, measurable airway metric linked to survival that can be targeted in training and protocols to improve OHCA outcomes.
Clinical Implications: Emphasize techniques that minimize apnea duration during intubation (preoxygenation, apneic oxygenation, first-pass success strategies) and monitor apnea interval as a quality metric.
Key Findings
- Median apnea interval during intubation attempts was 84 s (IQR 64–113 s) in VF-OHCA.
- Apnea interval ≤60 s associated with higher ROSC (72% vs 56%), survival to discharge (39% vs 25%), and favorable neurologic survival (39% vs 23%).
- High chest compression fraction (overall 85%) was maintained, suggesting apnea interval independently contributes to outcomes.
Methodological Strengths
- Clear operational definition of apnea interval with objective ventilation timing.
- Multivariable logistic regression adjusting for confounders in a real-world EMS cohort.
Limitations
- Single metropolitan EMS system limits generalizability.
- Observational design cannot prove causality; residual confounding possible.
Future Directions: Test targeted interventions (e.g., apneic oxygenation, videolaryngoscopy protocols) to prospectively reduce apnea intervals and measure impact on survival.
BACKGROUND: Guidelines for out-of-hospital cardiac arrest (OHCA) resuscitation recommend advanced airway management without interrupting chest compressions. However, the extent and impact of interrupting ventilation is unknown. We described the apnea interval that occurs during tracheal intubation and its association with clinical outcomes. METHODS: We conducted a cohort investigation of adult ventricular fibrillation (VF) OHCA patients who underwent attempted tracheal intubation prior to return of spontaneous circulation (ROSC) in a metropolitan EMS system (2017-2020). Apnea interval was defined as elapsed time between last breath delivered before and first breath delivered following tracheal intubation attempt. We used multivariable logistic regression to determine the relationship between apnea interval (≤60 s vs > 60 s) and outcomes: ROSC, survival to hospital discharge, and favorable neurologic survival (CPC 1-2). RESULTS: Among 254 patients, median age was 65 years, 18% were female, and 98% had tracheal intubation success. Overall, 151 (59%) achieved ROSC, 71 (28%) survived to discharge, and 67 (26%) with favorable survival. The median apnea interval during attempted tracheal intubation was 84 s (64-113 s). Median chest compression fraction was 85% overall and 87% during the apnea interval. In unadjusted and adjusted analyses, a shorter apnea interval was associated with better outcomes: ROSC (72% vs 56%), survival (39% vs 25%), and favorable survival (39% vs 23%) (p < 0.05 for each comparison). CONCLUSIONS: In this VF-OHCA cohort, shorter apnea intervals (≤60 s) were associated with greater likelihood of favorable outcomes. Given its variability and relationship to outcomes, the apnea interval may be a modifiable measure to improve OHCA survival.