Daily Anesthesiology Research Analysis
An international Delphi consensus refined how ARDS should be conceptually defined and highlighted priorities for subphenotyping, with implications for diagnosis and research. A randomized trial in total knee arthroplasty found spinal mepivacaine modestly hastened motor recovery versus bupivacaine without improving ambulation or discharge. A meta-analysis of 12 RCTs showed transversus abdominis plane blocks reduce pain and opioid use after gastric surgery and modestly speed gastrointestinal recov
Summary
An international Delphi consensus refined how ARDS should be conceptually defined and highlighted priorities for subphenotyping, with implications for diagnosis and research. A randomized trial in total knee arthroplasty found spinal mepivacaine modestly hastened motor recovery versus bupivacaine without improving ambulation or discharge. A meta-analysis of 12 RCTs showed transversus abdominis plane blocks reduce pain and opioid use after gastric surgery and modestly speed gastrointestinal recovery.
Research Themes
- Refining ARDS definition and advancing subphenotyping for precision critical care
- Optimizing neuraxial anesthesia agents for rapid functional recovery
- Regional anesthesia in ERAS pathways for upper gastrointestinal surgery
Selected Articles
1. Defining and subphenotyping ARDS: insights from an international Delphi expert panel.
A four-round Delphi process involving diverse ARDS experts achieved consensus on a conceptual model and key definition components across clinical, research, and educational contexts, and endorsed advancing subphenotyping. The panel identified knowledge gaps and research priorities to refine diagnostic precision and account for ARDS heterogeneity.
Impact: This consensus clarifies what should constitute an ARDS definition and prioritizes subphenotyping, guiding future trials and diagnostic strategies in critical care.
Clinical Implications: Refined ARDS components and emphasis on subphenotyping can improve patient selection, stratification in trials, and potentially personalize ventilatory and adjunctive therapies.
Key Findings
- Consensus on a conceptual model and defining components for ARDS across clinical, research, and educational use cases.
- Endorsement of further research into ARDS subphenotyping to address heterogeneity.
- Use of a rigorous, anonymous multi-round Delphi method with diverse international experts and predefined quantitative criteria.
Methodological Strengths
- Structured four-round Delphi with anonymity, minimizing groupthink and bias.
- Global, multidisciplinary expert participation ensuring broad applicability.
Limitations
- Consensus does not equate to empirical validation; proposed components were not prospectively tested.
- Operational thresholds and diagnostic performance metrics were not established.
Future Directions: Prospective validation of proposed components and subphenotypes, integration with biomarkers and imaging, and evaluation of phenotype-guided treatment strategies.
Although the definition of acute respiratory distress syndrome (ARDS) has undergone numerous revisions aimed at enhancing its diagnostic accuracy and clinical practicality, the usefulness and precision of these definitions remain matters of ongoing discussion. In this Position Paper, we report on a Delphi study to reach a consensus on the conceptual model of ARDS, specifically identifying its defining components within clinical, research, and educational contexts as well as exploring the potential role of subphenotyping. We did a
2. Mepivacaine versus bupivacaine spinal anesthesia for return of motor function following total knee arthroplasty: a randomized controlled trial.
In 163 TKA patients, spinal mepivacaine shortened time to motor recovery by about 19 minutes and reduced urinary retention versus bupivacaine, but did not improve time to ambulation, ambulation distance, same-day discharge, length of stay, or opioid use. PACU pain scores were higher with mepivacaine but equalized by 6–48 hours.
Impact: This well-powered RCT provides high-quality comparative data for selecting intrathecal local anesthetics in fast-track arthroplasty pathways.
Clinical Implications: Mepivacaine may be preferred when modestly faster motor recovery and lower urinary retention are priorities, but expectations for earlier ambulation or discharge should be tempered.
Key Findings
- Time to return of motor function was shorter with mepivacaine (median 210 vs 229 minutes; p<0.001).
- Urinary retention was less frequent with mepivacaine (36% vs 57%; p=0.007).
- No differences in time to first ambulation, ambulation distance, same-day discharge, length of stay, or opioid consumption.
- Higher PACU pain with mepivacaine, with no differences by 6–48 hours.
Methodological Strengths
- Randomized controlled design with trial registration.
- Clinically relevant outcomes including ambulation and discharge metrics.
Limitations
- Single procedure type limits generalizability beyond TKA.
- No blinding details provided; modest absolute difference in motor recovery.
Future Directions: Evaluate dosing strategies and adjuncts to balance faster motor recovery with early analgesia; assess cost-effectiveness and patient-centered outcomes in fast-track programs.
BACKGROUND: Demand for same-day discharge pathways and early ambulation following knee arthroplasty continues to increase. While spinal anesthesia with mepivacaine versus bupivacaine may promote return of motor function and ambulation, there are limited randomized trials evaluating this in knee arthroplasty patients. This study hypothesized that spinal mepivacaine would result in earlier return of motor function, promoting ambulation and same-day discharge. METHODS: Patients undergoing primary total knee arthroplasty (n=163) were enrolled and randomized patients to mepivacaine (60 mg) or isobaric bupivacaine (10 mg) for spinal anesthesia. The primary outcome was time to return of motor function. Additional outcomes included time to first ambulation, distance at first ambulation, same-day discharge rate, length of stay, postoperative pain, opioid consumption, and side effects. RESULTS: Patients receiving a mepivacaine spinal anesthetic had faster median (95% CI) time to return of motor function, (210 min (200, 216) vs 229 (223, 237) min, p<0.001) and lower rates of urinary retention (36% vs 57%, p=0.007). Mepivacaine patients exhibited higher pain scores in the post-anesthesia care unit (32.4 vs 9.5 mm, p<0.001) but no differences at 6, 24, or 48 hours postoperative. Opioid consumption did not differ at any time point (p=0.769). There were no differences in time to first ambulation, distance at first ambulation, same-day discharge rate, length of stay, nausea, vomiting, pruritus, or transient neurological symptoms between groups. CONCLUSIONS: Although mepivacaine expedited return of motor function after knee arthroplasty, a clinically relevant 20% reduction was not observed. Ambulation times and same-day discharge rates did not differ. TRIAL REGISTRATION NUMBER: NCT05765682.
3. Efficacy of transversus abdominis plane block for gastric surgery: a meta-analysis.
Across 12 RCTs (n=841), TAP blocks after gastric surgery lowered pain scores through 48 hours, reduced opioid consumption, and modestly accelerated first ambulation and flatus, without shortening hospital stay. Findings support TAP as part of multimodal ERAS analgesia for gastric procedures.
Impact: Synthesizes randomized evidence specific to gastric surgery, informing ERAS analgesic strategies with consistent benefits in pain and opioid reduction.
Clinical Implications: Consider incorporating TAP blocks into standard gastric surgery ERAS pathways to reduce pain and opioids and facilitate early GI recovery, while recognizing limited impact on length of stay.
Key Findings
- TAP reduced postoperative VAS pain scores at 1–48 hours (WMD ~ -0.62 to -0.97).
- Postoperative opioid consumption decreased with TAP (WMD -1.89).
- Earlier first flatus (WMD -5.17 hours) and a borderline improvement in time to ambulation (SMD -0.46).
- No significant difference in hospital length of stay.
Methodological Strengths
- Exclusive inclusion of RCTs with multi-database search and dual-reviewer screening.
- Consistent effects across multiple time points and outcomes.
Limitations
- Potential heterogeneity in TAP techniques, surgical approaches, and perioperative care.
- Unclear assessment of publication bias and variable reporting quality across trials.
Future Directions: Head-to-head comparisons of TAP variants (e.g., subcostal vs lateral), local anesthetic dosing strategies, and integration with adjunct blocks in specific gastric procedures.
BACKGROUND: Multimodal analgesia is an important component of Enhanced Recovery After Surgery (ERAS). Transversus abdominis plane (TAP) block helps achieve this pain management in various types of surgeries. To evaluate the efficacy of TAP block versus non-TAP approaches for postoperative pain management and recovery after gastric surgery. METHODS: A systematic literature search across four databases (Cochrane, Embase, Web of Science, PubMed) until February 2024 identified relevant randomized controlled trials (RCTs) evaluating TAP block in gastric surgery. Two independent reviewers screened studies, extracted data, and assessed analyses. PRIMARY OUTCOME: postoperative pain scores. SECONDARY OUTCOMES: postoperative opioid consumption, hospital stay, time to ambulation, and time to flatus. RESULTS: Twelve RCTs involving 841 participants were included. Compared to non-TAP, the TAP group demonstrated significantly lower visual analog scale (VAS) pain scores at 1, 3, 6, 12, 24, and 48 h postoperatively (WMD range: -0.62 to -0.97). Time to first ambulation (SMD - 0.46; 95% CI: -0.92, 0.00) and first flatus (WMD - 5.17; 95% CI: -8.58, -1.77) were shorter in the TAP group. Postoperative opioid consumption was reduced with TAP (WMD - 1.89; 95% CI: -2.41, -1.37), with no difference in hospital stay between groups. CONCLUSION: TAP block effectively relieves pain after gastric surgery, decreases postoperative morphine requirements, and modestly shortens bed rest duration while promoting intestinal function recovery. However, it does not significantly affect the overall hospital length of stay.