Daily Anesthesiology Research Analysis
Analyzed 79 papers and selected 3 impactful papers.
Summary
Three perioperative studies stand out today. A large double-blind RCT shows that adding perineural esketamine to ropivacaine for genicular/IPACK blocks markedly reduces chronic postsurgical pain after total knee arthroplasty. Another RCT suggests ephedrine lowers early postoperative delirium versus phenylephrine in elderly arthroplasty patients, while a 116,996-patient cohort links accelerated biological aging to higher intraoperative hypotension risk, informing preoperative risk stratification.
Research Themes
- Prevention of chronic postsurgical pain with adjuvant regional anesthesia
- Vasopressor choice and neurocognitive outcomes (postoperative delirium)
- Biological aging metrics for perioperative hemodynamic risk stratification
Selected Articles
1. Esketamine as an Adjuvant to Ropivacaine in Genicular Nerve and IPACK Blocks for Total Knee Arthroplasty: A Double-Blind Randomized Trial.
In a double-blind RCT of 367 TKA patients, perineural esketamine (0.2 mg/kg) added to 0.5% ropivacaine for genicular and IPACK blocks reduced 6-month CPSP to 4.9% versus 17.9% (ropivacaine) and 27.0% (control). Pain burden and early functional recovery improved without increased adverse events.
Impact: Demonstrates a pragmatic, scalable strategy to prevent chronic postsurgical pain after TKA using a familiar regional anesthesia framework with a novel adjuvant.
Clinical Implications: Consider perineural esketamine (0.2 mg/kg) as an adjuvant to ropivacaine for genicular and IPACK blocks to mitigate CPSP risk and improve early recovery after TKA, with ongoing vigilance for neurotoxicity or local reactions.
Key Findings
- Esketamine adjuvant reduced 6-month CPSP to 4.9% versus 17.9% (ropivacaine) and 27.0% (control).
- Overall pain burden (AUC) and early functional metrics (eg, TUG, walking distance, QoR-15) improved in the esketamine group.
- No increase in adverse events was reported with perineural esketamine.
Methodological Strengths
- Prospective, randomized, double-blind design with three-arm comparison
- Clinically meaningful primary endpoint at 6 months with functional secondary outcomes
Limitations
- Single-trial setting with journal not field-top; external validation needed
- Details on long-term safety of perineural esketamine remain limited
Future Directions: Replicate in multicenter settings, define optimal dose ranges and formulations, and assess durability beyond 6–12 months and in other orthopedic procedures.
2. Effect of Ephedrine versus Phenylephrine on Postoperative Delirium in Elderly Patients Undergoing Total Hip or Knee Arthroplasty: A Randomized Controlled Trial.
In elderly arthroplasty patients, ephedrine to treat intraoperative hypotension reduced 3-day postoperative delirium from 22.4% to 7.7% versus phenylephrine. Ephedrine also lowered intraoperative bradycardia but required more intraoperative opioids, with no difference in postoperative pain.
Impact: Provides actionable evidence that vasopressor selection may influence early neurocognitive outcomes, a modifiable factor in enhanced recovery pathways for older adults.
Clinical Implications: When correcting intraoperative hypotension in elderly arthroplasty patients, ephedrine may be preferred over phenylephrine to reduce early postoperative delirium, while monitoring for higher intraoperative opioid needs.
Key Findings
- Postoperative delirium within 3 days: 7.7% (ephedrine) vs 22.4% (phenylephrine), RR 0.344, p=0.019.
- Ephedrine reduced intraoperative bradycardia versus phenylephrine.
- Higher intraoperative opioid consumption with ephedrine did not translate into higher postoperative pain.
Methodological Strengths
- Randomized controlled design with standardized delirium assessment (3D-CAM)
- Clear, clinically relevant primary endpoint within a defined postoperative window
Limitations
- Single-center trial with modest sample size; limited generalizability
- No cerebral oxygen saturation monitoring; delirium follow-up limited to 3 days
Future Directions: Confirm in multicenter trials with longer delirium follow-up, cerebral oximetry, and mechanistic endpoints (e.g., cerebral perfusion/EEG).
3. Associations of accelerated biological aging with intraoperative hypotension in major surgery: a multicenter cohort study of 116,996 patients.
Across 116,996 surgical patients at three centers, higher Phenotypic Age Acceleration was independently associated with increased incidence, duration, and AUC of intraoperative hypotension (MAP <60 mmHg). The findings support incorporating biological aging metrics into preoperative risk stratification.
Impact: Introduces a scalable, biology-informed predictor for a common and harmful intraoperative event, enabling precision perioperative management beyond chronological age.
Clinical Implications: Use biological aging metrics (e.g., PhenoAgeAccel) to identify patients at higher risk for IOH, prompting proactive hemodynamic strategies (e.g., monitoring intensity, vasopressor planning, fluid responsiveness guidance).
Key Findings
- Phenotypic Age Acceleration was independently associated with higher IOH incidence.
- Higher biological aging correlated with longer IOH duration and greater MAP<60 mmHg AUC.
- Associations were robust across sensitivity and subgroup analyses in 116,996 patients.
Methodological Strengths
- Very large multicenter cohort with standardized MAP thresholds and integrated AUC metrics
- Adjusted analyses with multiple sensitivity and subgroup checks
Limitations
- Retrospective design; residual confounding cannot be excluded
- External generalizability outside the included health systems requires validation
Future Directions: Prospective validation integrating biological aging with dynamic hemodynamic monitoring and testing targeted interventions for high-risk phenotypes.