Daily Anesthesiology Research Analysis
Analyzed 199 papers and selected 3 impactful papers.
Summary
Three papers stand out today in anesthesiology and perioperative medicine: a meta-analysis shows that higher fixed PEEP during one-lung ventilation increases intraoperative hypotension without reducing pulmonary complications; a large multinational perioperative cohort suggests continuing metformin on the day of surgery is associated with slightly more days alive and at home; and a comprehensive meta-analysis refines global and subgroup prevalence estimates for fibromyalgia, informing perioperative pain risk stratification.
Research Themes
- Intraoperative ventilation strategy during thoracic anesthesia
- Perioperative management of type 2 diabetes medications
- Epidemiology of chronic pain conditions relevant to perioperative care
Selected Articles
1. Higher vs. lower positive end-expiratory pressure during one-lung ventilation for thoracic surgery: a systematic review and meta-analysis.
Across eight RCTs with 2,747 thoracic surgery patients, higher fixed PEEP during one-lung ventilation increased intraoperative hypotension without reducing postoperative pulmonary complications. The findings argue against routine use of higher fixed PEEP and support research into individualized PEEP titration.
Impact: This directly informs a common intraoperative ventilation choice in thoracic anesthesia using pooled RCT evidence and challenges a frequently used strategy.
Clinical Implications: Avoid routine high fixed PEEP during one-lung ventilation given increased hypotension without clinical pulmonary benefit; consider individualized PEEP titration guided by physiology or imaging rather than fixed levels.
Key Findings
- Higher fixed PEEP during OLV significantly increased intraoperative hypotension risk.
- No reduction in postoperative pulmonary complications with higher PEEP compared to lower PEEP.
- Evidence synthesis used REML random-effects modeling with GRADE assessment and was PROSPERO-registered.
Methodological Strengths
- Meta-analysis of randomized controlled trials with predefined outcomes
- PROSPERO-registered protocol and GRADE certainty assessment
Limitations
- Heterogeneity in PEEP levels and co-interventions across trials
- Fixed PEEP strategies studied; limited data on individualized titration approaches
Future Directions: Prospective trials comparing individualized PEEP titration (e.g., EIT-, driving pressure-, or compliance-guided) versus fixed PEEP strategies on patient-centered outcomes.
BACKGROUND: Higher fixed positive end-expiratory pressure (PEEP) during one-lung ventilation (OLV) may improve intraoperative oxygenation but could compromise haemodynamic stability. We performed a systematic review and meta-analysis to evaluate the effects of higher vs. lower fixed PEEP strategies on intraoperative hypotension and postoperative pulmonary complications (PPCs) in patients undergoing thoracic surgery. METHODS: We searched MEDLINE, Embase, and CENTRAL from inception to 7 March 2026, supplemented by trial registries. Parallel-group randomised controlled trials (RCTs) comparing higher vs. lower fixed PEEP during OLV were eligible. Co-primary outcomes were intraoperative hypotension and PPCs. Pooled risk ratios (RRs) and mean differences (MDs) were estimated using random-effects models with restricted maximum likelihood (REML) estimation. Certainty of evidence was assessed using GRADE. This review was registered in PROSPERO (CRD420261329237). RESULTS: Eight RCTs (2,747 patients) were included. Higher PEEP was associated with a significantly increased risk of intraoperative hypotension (2 studies; CONCLUSIONS: Higher fixed PEEP during OLV significantly increases intraoperative hypotension risk without reducing PPCs. The haemodynamic cost of this strategy is not offset by measurable clinical benefit. Routine application of higher fixed PEEP during OLV should be approached with caution, and future research should evaluate individualised PEEP titration strategies. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD420261329237, identifier CRD420261329237.
2. The Prevalence of Fibromyalgia in the General Population and At-Risk Subpopulations: A Systematic Review and Meta-Analysis.
Synthesizing 882 studies across 38 countries, fibromyalgia prevalence is approximately 1.4% in the general population but substantially higher in defined at-risk subgroups (e.g., autoimmune and inflammatory disorders). Heterogeneity is extreme, and publication year and socioeconomic status (HDI) modulate prevalence estimates.
Impact: This large synthesis in a leading anesthesiology journal refines pain epidemiology and highlights high-risk subgroups, informing perioperative screening and resource allocation for pain management.
Clinical Implications: Perioperative teams should anticipate higher chronic pain burden in specific comorbidities (e.g., chronic urticaria, interstitial cystitis) and consider targeted screening, counseling, and multimodal analgesia planning while acknowledging diagnostic heterogeneity.
Key Findings
- Global pooled fibromyalgia prevalence in the general population: 1.40% (95% CI 0.49–2.47) with I2 = 100% and very low certainty.
- Markedly elevated prevalence in at-risk subpopulations: chronic urticaria 37.1%, interstitial cystitis 30.8%, systemic sclerosis 20.6%, celiac disease 20.5%, inflammatory bowel disease 19.9%.
- Meta-regression: publication year (β = 0.008, P < .001) and Human Development Index (β = 0.725, P = .002) significantly moderated prevalence.
Methodological Strengths
- Extremely large evidence base spanning 38 countries with predefined subgroup and meta-regression analyses
- Use of inverse variance heterogeneity model with Freeman–Tukey transformation
Limitations
- Extreme heterogeneity (I2 = 100%) and very low certainty limit precision and generalizability
- Diagnostic criteria and study quality varied widely across included studies
Future Directions: Standardize diagnostic criteria and conduct high-quality population-based studies in underrepresented regions; evaluate perioperative outcomes in high-risk subgroups.
Estimates of fibromyalgia prevalence vary widely worldwide due to differences in diagnostic criteria, study methodology, and population characteristics. Accurate estimates are essential to inform population-level surveillance, guide resource allocation, and highlight disparities in disease recognition and access to care. The objective of this systematic review and meta-analysis was to determine the global prevalence of fibromyalgia in the general population, and secondarily to identify factors moderating prevalence variation and to assess prevalence in defined at-risk subpopulations. Pooled prevalence estimates with 95% confidence intervals (CIs) were calculated using the inverse variance heterogeneity model with Freeman-Tukey transformation. Subgroup analyses were performed by sex, diagnostic criteria, country, and other study characteristics, and meta-regression assessed moderators including publication year and Human Development Index (HDI). Of 21,645 records identified, 1,728 underwent full-text review and 882 studies were included in the final analysis. Across 38 countries and 30,070,032 individuals (188 studies), the pooled fibromyalgia prevalence in the general population was 1.40% (95% CI, 0.49-2.47), with substantial heterogeneity (I2 = 100%) and very low certainty of evidence. Among at-risk subpopulations (9,771,123 participants; 768 studies), prevalence was markedly higher in autoimmune and inflammatory conditions, such as chronic urticaria (37.1%), interstitial cystitis (30.8%), systemic sclerosis (20.6%), celiac disease (20.5%), and inflammatory bowel disease (19.9%), and elevated in chronic pain, rheumatologic, and post-infection cohorts. Meta-regression identified publication year (β = 0.008, P < .001) and HDI (β = 0.725, P = .002) as significant moderators of prevalence. In conclusion, fibromyalgia affects 1% to 2% of the global population, with substantially higher rates in at-risk subpopulations. Temporal and socioeconomic trends emphasize diagnostic inconsistency and global disparities in care.
3. Withholding or continuing glucose-lowering drugs for elective surgery in patients with type 2 diabetes mellitus: a secondary analysis of the MOPED international, prospective, observational study.
In a secondary analysis of a large prospective multinational cohort, continuing metformin on the day of surgery was associated with a modest increase in days alive and at home at 30 days. No clear association was observed for SGLT2 inhibitors or GLP-1 receptor agonists, likely due to small sample sizes.
Impact: This study provides contemporary, multicountry evidence addressing a common perioperative dilemma and supports not routinely withholding metformin in elective surgery.
Clinical Implications: Perioperative protocols may consider continuing metformin on the day of elective surgery in stable patients, with individualized assessment; caution remains for newer agents given limited power and known risks (e.g., euglycemic ketoacidosis with SGLT2i).
Key Findings
- Among metformin users (n=3,623), continuation on the day of surgery (n=421) was associated with higher DAH-30 (28 vs 27 days; adjusted +0.47 days, P=0.044).
- No significant association of continuation vs withholding was observed for SGLT2 inhibitors (n=836) or GLP-1 receptor agonists (n=304).
- The analysis spanned 21 countries and 89 centers in a prospective observational framework.
Methodological Strengths
- Large, prospective, multicountry observational dataset with prespecified covariate adjustment
- Patient-centered primary outcome (DAH-30) relevant to perioperative value-based care
Limitations
- Nonrandomized exposure with potential residual confounding and selection bias
- Limited power for SGLT2i and GLP-1 RA subgroups constrains inference
Future Directions: Pragmatic randomized or emulation studies to test continuation strategies across glucose-lowering drug classes with safety endpoints; mechanistic work on perioperative glycemic and lactate dynamics.
BACKGROUND: There are conflicting guidelines on whether patients with type 2 diabetes mellitus should withhold or continue glucose-lowering drugs before surgery, especially newer agents. We tested the hypothesis that continuing glucose-lowering drugs increases days alive at home and out of hospital at 30 days (DAH-30). METHODS: We performed a secondary analysis of a prospective, observational study in 21 European countries of patients with type 2 diabetes mellitus undergoing elective surgery. The primary outcome was DAH-30. The exposure of interest was the continuation or discontinuation of glucose-lowering drugs (metformin, sodium-glucose cotransporter 2 inhibitors [SGLT2i], glucagon-like peptide-1 receptor agonists [GLP-1 RA]). Median (interquartile [IQR]) values are shown. RESULTS: Between January 2021 and December 2024, 5767 participants with type 2 diabetes mellitus (age 64 [range: 22-89] yr; 43% female) were enrolled from 89 centres, with 4988 (87%) undergoing elective surgery. For 3623/5767 (73%) participants receiving metformin, DAH-30 was higher (28 days [24-29]) in 421/3623 (12%) participants who continued metformin on the day of surgery compared with 27 days (23-29) in 3202 of 5767 (88%) participants who had not taken metformin (P=0.001). After adjusting for prespecified covariates, continuing metformin on the day of surgery remained associated with higher DAH-30 (0.47 days [95% confidence interval:0.01-0.93]; P=0.044). No association was found for either stopping/continuing SGLT2i (n=836 participants) or GLP-1 RA (n=304 participants) with DAH-30. CONCLUSIONS: Continuing metformin during surgery among patients with type 2 diabetes mellitus was associated with marginally shorter DAH-30, but the sample size for participants receiving SGLT2i and GLP-1 RA therapy precluded any meaningful estimates. TRACKER ID: ESA-IC_CTN_MOPED.