Daily Anesthesiology Research Analysis
Across anesthesiology and perioperative medicine, three studies advance precision risk assessment and therapy selection: a double-blind RCT shows inhaled nitric oxide does not prevent AKI after prolonged cardiopulmonary bypass in patients with endothelial dysfunction; a Medicare analysis links advanced CKM syndrome stages to higher postoperative MACE and mortality; and large dual-cohort data identify creatinine–cystatin C eGFR discordance as a novel predictor of postoperative complications.
Summary
Across anesthesiology and perioperative medicine, three studies advance precision risk assessment and therapy selection: a double-blind RCT shows inhaled nitric oxide does not prevent AKI after prolonged cardiopulmonary bypass in patients with endothelial dysfunction; a Medicare analysis links advanced CKM syndrome stages to higher postoperative MACE and mortality; and large dual-cohort data identify creatinine–cystatin C eGFR discordance as a novel predictor of postoperative complications.
Research Themes
- Perioperative risk stratification and phenotyping
- Organ protection and negative trials informing practice
- Biomarker-driven precision perioperative medicine
Selected Articles
1. Nitric Oxide to Reduce Acute Kidney Injury in Patients with Pre-existing Endothelial Dysfunction Requiring Prolonged Cardiopulmonary Bypass: A Randomized Clinical Trial.
In a double-blind RCT of 250 cardiac surgery patients with endothelial dysfunction undergoing prolonged CPB, perioperative inhaled NO (80 ppm for 24 h) did not reduce AKI by KDIGO criteria or RRT use at any follow-up time point. The results argue against routine NO use for AKI prevention in this high-risk subgroup.
Impact: A well-controlled, registered RCT providing definitive negative evidence in a biologically plausible subgroup helps de-implement low-value therapy and refocus organ-protection strategies.
Clinical Implications: Do not routinely administer 80 ppm inhaled NO for 24 h to prevent AKI in cardiac surgery patients with endothelial dysfunction undergoing prolonged CPB; emphasize multimodal AKI prevention bundles (hemodynamics, nephrotoxin avoidance, perfusion strategies) and target alternative trials.
Key Findings
- AKI incidence: 44.0% (NO) vs 43.2% (control); adjusted OR 1.00 (95% CI 0.59–1.69).
- No differences in AKI severity (KDIGO stages 1–3) between groups.
- No reduction in renal replacement therapy during hospitalization or at 6 weeks, 90 days, or 1 year.
Methodological Strengths
- Double-blind, placebo-controlled, randomized design with trial registration (NCT02836899).
- Clinically meaningful outcomes using KDIGO criteria and longitudinal RRT assessments.
Limitations
- Single-center design may limit generalizability.
- Trial may be underpowered to detect smaller effects on less frequent endpoints (e.g., long-term RRT).
Future Directions: Explore alternative perioperative nephroprotection strategies (e.g., perfusion pressure targets, hemolysis mitigation, nitric oxide bioavailability via different routes) and phenotype-enriched trials beyond endothelial dysfunction alone.
2. Association of the cardiovascular-kidney-metabolic syndrome and adverse outcomes after noncardiac surgery.
In a Medicare cohort of over 2.1 million surgeries, advanced CKM stages (≥3) independently increased risks of MACE (AOR 1.70–3.42), mortality (1.52–3.61), and non-home discharge (1.98–4.25). These associations were consistent across race/ethnicity and sex within CKM stages.
Impact: Provides scalable, phenotype-based perioperative risk stratification using CKM staging across a national dataset, informing preoperative evaluation and resource planning.
Clinical Implications: Incorporate CKM staging into preoperative assessment to identify patients at high risk for MACE and mortality, guide optimization (cardiac, renal, metabolic), and plan postoperative disposition and monitoring.
Key Findings
- Advanced CKM stages (≥3) associated with higher MACE risk (AOR 1.70–3.42).
- Mortality and non-home discharge risks increased with CKM stage (AOR 1.52–3.61 and 1.98–4.25).
- No excess MACE risk differences by race/ethnicity or sex within the same CKM stage.
Methodological Strengths
- Very large national cohort with detailed administrative data.
- Multivariable modeling across CKM stages with assessment of disparities.
Limitations
- Retrospective administrative data subject to residual confounding and misclassification.
- Limited generalizability to patients under 65 years or outside Medicare.
Future Directions: Prospective validation of CKM-integrated perioperative risk tools and interventional studies targeting modifiable CKM components to reduce postoperative events.
3. Discordances Between Preoperative Creatinine- and Cystatin C-Based Estimated Glomerular Filtration Rate and Outcomes After Noncardiac Surgery: An Observational Study.
Across two large Chinese surgical cohorts (n=35,488 and 23,417), a more negative preoperative eGFRdiff (cystatin C minus creatinine) independently predicted higher risks of a composite of postoperative complications and death, with similar effect sizes per 10 mL/min/1.73 m² decrease.
Impact: Introduces a simple, physiologically grounded biomarker (eGFRdiff) for perioperative risk stratification with consistent performance across independent cohorts.
Clinical Implications: Consider measuring both cystatin C and creatinine to compute eGFRdiff in preoperative evaluation; a negative eGFRdiff may flag higher risk for cardiovascular events, AKI, infections, and pulmonary complications to guide monitoring and optimization.
Key Findings
- Per 10 mL/min/1.73 m² decrease in eGFRdiff, adjusted ORs for the composite outcome were 1.12 (95% CI 1.09–1.15) and 1.11 (95% CI 1.09–1.14) in two cohorts (P<0.001).
- Associations were consistent across component outcomes: cardiovascular events, AKI, infections, pulmonary complications, and death.
- Findings replicated across two geographically distinct, ethnically different hospital cohorts.
Methodological Strengths
- Large, dual-cohort design with multivariable adjustment for demographics, comorbidities, and labs.
- Consistent effect sizes across independent populations and outcomes.
Limitations
- Retrospective design with potential residual confounding and assay variability.
- Generalizability beyond Asian populations and two-center settings requires validation.
Future Directions: Prospective, multicenter validation and integration of eGFRdiff into perioperative risk calculators; exploration of mechanisms underlying discordance and targeted optimization strategies.