Daily Anesthesiology Research Analysis
Three perioperative studies stand out today. A meta-analysis of randomized trials supports opioid-free anesthesia for laparoscopic surgery, reducing early postoperative pain. A post-hoc analysis of a randomized fluid trial shows that the diagnostic performance of PPV/PVI/CO for hypovolemia depends on the infusion fluid used. A double-blind RCT demonstrates that an esketamine-based opioid-sparing protocol improves early recovery after urologic surgery.
Summary
Three perioperative studies stand out today. A meta-analysis of randomized trials supports opioid-free anesthesia for laparoscopic surgery, reducing early postoperative pain. A post-hoc analysis of a randomized fluid trial shows that the diagnostic performance of PPV/PVI/CO for hypovolemia depends on the infusion fluid used. A double-blind RCT demonstrates that an esketamine-based opioid-sparing protocol improves early recovery after urologic surgery.
Research Themes
- Opioid-free and opioid-sparing anesthesia
- Hemodynamic monitoring and fluid responsiveness
- Enhanced recovery after surgery
Selected Articles
1. Safety and effectiveness of multimodal opioid-free anaesthesia for pain and recovery after laparoscopic surgery: a systematic review and meta-analysis.
Across 12 randomized trials (983 patients), opioid-free anesthesia was associated with lower early postoperative pain (0–2 h; MD −1.29 on a 0–10 scale). The synthesis also evaluated opioid consumption, QoR-40, PONV and recovery metrics, supporting OFA as a viable strategy to enhance early recovery after laparoscopy.
Impact: This is the most comprehensive synthesis to date for OFA in laparoscopy, providing higher-level evidence to inform ERAS pathways and analgesic protocols.
Clinical Implications: Consider adopting multimodal OFA protocols for laparoscopic procedures to reduce early pain and potentially improve recovery metrics (e.g., PONV, readiness for discharge), while standardizing regimen components and monitoring hemodynamics.
Key Findings
- Included 12 RCTs with 983 patients undergoing laparoscopic surgery.
- OFA reduced early postoperative pain at 0–2 hours versus opioid anesthesia (MD −1.29; 95% CI −2.23 to −0.36).
- Outcomes synthesized included opioid consumption, QoR-40, PONV, extubation time, and PACU discharge time under random-effects modeling.
Methodological Strengths
- PRISMA-guided systematic review and meta-analysis with PROSPERO registration.
- Random-effects modeling with prespecified primary and secondary outcomes across multiple RCTs.
Limitations
- Heterogeneity in OFA drug combinations and dosing across trials.
- Limited to laparoscopic surgery; durability of benefits beyond 24 hours not fully defined.
Future Directions: Define standardized OFA regimens, assess safety signals (e.g., bradycardia/hypotension), and extend evaluation to open procedures and high-risk populations with longer follow-up.
2. Detection of hypovolemia by non-invasive hemodynamic monitoring during major surgery using Ringer´s solution, 5% albumin, or 20% albumin as infusion fluid: a post-hoc analysis of a randomized clinical trial.
In a post-hoc analysis of a randomized trial (n=42), the diagnostic utility of PPV, PVI, and CO for hypovolemia depended on the infusion fluid: PPV performed best with 5% albumin, PVI with Ringer’s, and CO with 20% albumin. Albumin strategies better restored intravascular volume than Ringer’s alone, but 20% albumin increased vascular resistances.
Impact: It challenges the universal application of dynamic indices by showing fluid-dependent performance, with direct implications for intraoperative goal-directed therapy.
Clinical Implications: Interpret PPV/PVI/CO in the context of the fluid being infused; adapt thresholds and response criteria accordingly. Consider colloid (albumin) when rapid intravascular refilling is needed, while monitoring for increased vascular resistance with 20% albumin.
Key Findings
- Ringer-only replacement produced slight hypovolemia (mean ~313 mL), lower MAP, higher HR/PPV, and greater vasopressor need.
- 5% and 20% albumin restored intravascular volume more effectively (higher mean circulatory filling pressure; stable/decreased PPV).
- ROC analyses: PPV best detected >500 mL hypovolemia with 5% albumin; PVI was reliable with Ringer’s; CO indicated hypovolemia with 20% albumin.
Methodological Strengths
- Randomized fluid assignment with comprehensive hemodynamic profiling including Guyton-derived parameters.
- Concurrent assessment of PPV, PVI, and CO under different fluid strategies with ROC analysis.
Limitations
- Single-center, small sample size; post-hoc analysis of a randomized trial.
- CO measured via esophageal Doppler; generalizability to other monitors and surgical types may be limited.
Future Directions: Prospective validation of fluid-specific thresholds for PPV/PVI/CO and integration into adaptive goal-directed therapy algorithms.
3. Effect of Esketamine-Based Opioid-Sparing Anesthesia Protocol on the Quality of Early Recovery After Urological Surgery: A Randomized Clinical Trial.
In a double-blind RCT of elective urologic laparoscopy, esketamine-based opioid-sparing anesthesia increased 24-hour QoR-15 scores (median 114 vs 106). The protocol used 0.25 mg/kg induction and 0.125 mg·kg−1·h−1 maintenance infusions, supporting esketamine as a practical ERAS-compatible adjunct.
Impact: Provides randomized, blinded evidence that an esketamine-based opioid-sparing regimen improves early recovery quality, informing anesthetic plans where opioid minimization is prioritized.
Clinical Implications: Consider esketamine as part of an opioid-sparing anesthetic for laparoscopic urologic surgery to enhance early recovery (higher QoR-15), with protocolized dosing and vigilance for psychomimetic effects and hemodynamics.
Key Findings
- Randomized, double-blind, controlled trial in elective laparoscopic urologic surgery.
- Esketamine-based opioid-sparing anesthesia improved 24-hour QoR-15 (114 [108–116] vs 106 [102–109]).
- Protocol included 0.25 mg/kg induction and 0.125 mg·kg−1·h−1 maintenance infusion of esketamine.
Methodological Strengths
- Randomized, double-blind, controlled design with clearly defined dosing.
- Clinically meaningful primary endpoint (QoR-15) at 24 hours aligned with ERAS goals.
Limitations
- Single-center population limited to elective urologic laparoscopy; sample size not specified in abstract.
- Short-term follow-up; adverse events and opioid consumption details not fully reported in abstract.
Future Directions: Larger multicenter trials across surgical types to quantify safety, opioid-sparing magnitude, and patient-centered outcomes beyond 24–48 hours.