Daily Anesthesiology Research Analysis
Analyzed 101 papers and selected 3 impactful papers.
Summary
Three anesthesia-focused randomized trials stood out today. A double-blind RCT showed that the G protein-biased μ-agonist oliceridine halved intraoperative hypoxia versus sufentanil during sedated hysteroscopy. Two rigorous regional anesthesia trials refined block selection: a PENG block did not improve overall postoperative analgesia after ambulatory hip arthroscopy, and a 40-mL supra-inguinal fascia iliaca block rarely covered the obturator nerve, with an added obturator block failing to enhance analgesia after total knee arthroplasty.
Research Themes
- Opioid pharmacology and sedation safety
- Effectiveness and coverage of perioperative regional anesthesia
- Evidence-based optimization of block selection and recovery pathways
Selected Articles
1. Effect of oliceridine on hypoxia during sedated hysteroscopy: a Phase 4 randomized clinical trial.
In a double-blind randomized trial of 492 women undergoing sedated hysteroscopy, oliceridine halved intraoperative hypoxia versus sufentanil (9.8% vs 19.5%; RR 0.50) and was associated with higher nadir SpO2 and lower supplemental propofol use. Findings support oliceridine as a safer opioid option for sedation in this setting.
Impact: Demonstrates a clinically meaningful reduction in hypoxia with a novel biased agonist in a common ambulatory gynecologic procedure. Directly informs sedation safety and opioid selection.
Clinical Implications: For sedated hysteroscopy, oliceridine may be preferable to sufentanil to reduce intraoperative hypoxia and sedative requirements, particularly in patients at risk for respiratory compromise. Protocols should consider availability, dosing, and monitoring pathways.
Key Findings
- Intraoperative hypoxia incidence was lower with oliceridine vs sufentanil: 9.8% vs 19.5% (RR 0.50; 95% CI 0.32–0.79; p=0.002).
- Nadir oxygen saturation was higher in the oliceridine group (median 99% vs 97%; p<0.001).
- Oliceridine required less intraoperative propofol (median difference 10 mg; p=0.03) and showed favorable respiratory gas metrics.
Methodological Strengths
- Prospective, double-blind, randomized design with adequate sample size (n=492).
- Objective primary endpoint (hypoxia incidence) and registered protocol (ChiCTR2400090351).
Limitations
- Single-center study may limit generalizability to other settings and populations.
- Arterial blood gas and severe hypoxia outcomes were secondary and not fully detailed in the abstract.
Future Directions: Multicenter trials comparing oliceridine to other opioids and non-opioid regimens across diverse procedures and risk strata, with standardized respiratory endpoints and cost-effectiveness analyses.
BACKGROUND: Hypoxia is a common complication in hysteroscopic surgery under sedation with conventional opioids. Oliceridine, a novel G protein-biased μ-opioid receptor agonist, provides effective analgesia with fewer opioid-related adverse events, but its impact on intraoperative hypoxia in hysteroscopy remains unclear. METHODS: This is a single-center, prospective, double-blind, randomized clinical trial (TRN: ChiCTR2400090351), patients scheduled for hysteroscopic surgery under sedation were enrolled. Participants were randomized (1:1) to receive sufentanil (0.15 μg·kg⁻¹) or oliceridine (40 μg·kg⁻¹), combined with propofol (1.5 mg·kg⁻¹). The primary outcome was the incidence of intraoperative hypoxia from sedative drug initiation to hysteroscopy completion. Secondary outcomes included subclinical respiratory depression, severe hypoxia, airway interventions, supplemental propofol requirements, pain scores, arterial blood gas analysis, and patient and surgeon satisfaction. RESULTS: Among 492 randomized patients, 482 (98%) completed the trial. The incidence of intraoperative hypoxia is significantly lower in the oliceridine group (24 [9.8%] of 246 patients) than that in the sufentanil group (48 [19.5%] of 246 patients; RR, 0.50 [95% CI, 0.32-0.79]; P = 0.002). The lowest oxygen saturation is higher in the oliceridine group (99.0 [94.0, 100.0] vs 97.0 [90.0, 100.0], P < 0.001). Compared to sufentanil group, oliceridine group requires less propofol intraoperatively (median difference: 10.0 mg, 95% CI: 0.0 to 14.5; P = 0.03), has lower PaCO CONCLUSIONS: Oliceridine reduces the incidence of intraoperative hypoxia during hysteroscopic surgery under sedation, suggesting it may be a safer alternative to sufentanil. During hysteroscopic surgery, patients are often given medicines to reduce pain and discomfort. However, commonly used pain drugs can slow breathing and lead to low oxygen levels, which may be dangerous. Oliceridine is a new pain medicine designed to reduce these breathing-related side effects. In this study, nearly 500 women undergoing hysteroscopic surgery were randomly given either oliceridine or a conventional opioid, together with propofol. We closely monitored SpO
2. Analgesic efficacy of the ultrasound-guided pericapsular nerve group (PENG) block for ambulatory hip arthroscopy: a randomized controlled double-blind trial.
In 94 outpatients undergoing hip arthroscopy, preoperative PENG block did not improve 24-hour opioid use or QoR-15 versus sham, though it modestly reduced PACU opioids (−9.5 MME) and shortened PACU stay (−20.5 min). Routine preoperative PENG use is not supported beyond multimodal analgesia but may aid select early recoveries.
Impact: Provides high-quality, negative evidence in a fast-growing indication, preventing overuse of a motor-sparing block without demonstrable overall benefit.
Clinical Implications: Reserve PENG block for select patients to facilitate early PACU milestones; prioritize multimodal non-opioid analgesia and consider alternative blocks with proven benefit. Incorporate shared decision-making about expected benefits.
Key Findings
- No difference in 24-hour QoR-15 scores between PENG and control (96.8±20.9 vs 101.0±20.9; adjusted p=0.414).
- No difference in 24-hour opioid consumption; PENG reduced PACU opioid use (−9.5 MME; p=0.039).
- PENG shortened PACU stay by approximately 20.5 minutes (p=0.027) without differences in adverse effects.
Methodological Strengths
- Randomized, double-blind, sham-controlled design with prespecified co-primary outcomes.
- Use of validated patient-centered recovery metric (QoR-15) and standardized multimodal analgesia.
Limitations
- Single-center study; potential variability in surgical technique and anesthetic practices may limit generalizability.
- Not powered to detect rare block-related complications or long-term functional outcomes.
Future Directions: Evaluate PENG as a rescue block and in multimodal strategies versus comparator blocks (e.g., fascia iliaca, femoral) across diverse hip procedures with cost-effectiveness and functional outcomes.
BACKGROUND: Hip arthroscopy is an increasingly common outpatient surgical procedure where postoperative pain can be severe. Peripheral nerve blocks have been evaluated for analgesia following hip arthroscopy; however, there is no consensus on an optimal technique that provides effective local anesthetic-based postoperative analgesia without motor blockade. We hypothesized that the pericapsular nerve group (PENG) block would provide effective motor-sparing analgesia following ambulatory hip arthroscopy. METHODS: We conducted a randomized placebo-controlled double-blind trial comparing an ultrasound-guided PENG block with 20 mL of 0.5% ropivacaine to a control with a sham injection. Our primary outcomes were cumulative opioid consumption (oral morphine equivalent) and quality of recovery (QoR-15) scores at 24 hours postoperatively. Secondary outcomes included pain, postoperative opioid consumption, time to first analgesic request, postanesthesia care unit (PACU) length of stay, and opioid and block-related side effects. RESULTS: 94 patients were included (47 per group). QoR was similar between groups at 24 hours as measured by the QoR-15 (range 0-150, higher scores indicate better recovery): mean SD 96.8±20.9 in the PENG group versus 101.0±20.9 in the control group (mean difference -4.2; adjusted p=0.414). Opioid consumption at 24 hours was also similar between groups. In adjusted analyses, the PENG group required less opioid analgesia in the PACU (mean difference -9.5 MME; p=0.039) and had a shorter PACU stay (mean difference -20.5 min; p=0.027). Pain scores at rest and on movement decreased over time in both groups, with no consistent differences in overall pain trajectories. Opioid consumption at 48 hours, opioid-related adverse effects and block-related complications were similar between groups. CONCLUSIONS: When administered preoperatively, the PENG block provides only modest early perioperative benefits without improving overall postoperative analgesia or QoR in patients undergoing ambulatory hip arthroscopy. Based on these findings, routine preoperative use of the PENG block for ambulatory hip arthroscopy cannot be recommended beyond standard multimodal analgesia, although it may be considered selectively to facilitate early PACU recovery in carefully chosen patients. The potential role of postoperative PENG block as a rescue intervention warrants further investigation. TRIAL REGISTRATION NUMBER: NCT03449680; https://clinicaltrials.gov/study/NCT03449680.
3. Clinical evaluation of obturator nerve involvement following a supra-inguinal fascia iliaca compartment block: A randomized, double-blind trial.
A double-blind randomized trial in TKA patients showed that a 40-mL supra-inguinal fascia iliaca block seldom anesthetizes the obturator nerve, and adding a selective obturator nerve block did not reduce 24-hour morphine equivalents or improve recovery metrics, while causing more adductor weakness.
Impact: Clarifies nerve coverage limits of a widely used block and shows no analgesic gain from adding an obturator block after TKA, informing block selection and minimizing motor impairment.
Clinical Implications: Do not rely on SFICB (40 mL, 0.5% ropivacaine) for obturator coverage in TKA; routine addition of an obturator block is unlikely to improve analgesia and may increase adductor weakness. Focus on femoral/LFCN coverage and multimodal strategies.
Key Findings
- ONB success was 97.6% with active drug vs 2.4% with placebo (risk difference 95.2%; p<0.001).
- 24-hour IV morphine equivalents did not differ (median 6.8 mg vs 7.8 mg; p=0.156).
- Greater reduction in adductor strength occurred with active ONB; other recovery and pain outcomes were similar through 48 hours.
Methodological Strengths
- Randomized, double-blind, active-controlled design with fixed-sequence testing of dual primary outcomes.
- Standardized spinal anesthesia and postoperative analgesia protocols, with comprehensive sensorimotor assessments.
Limitations
- Single-center study; findings may not extrapolate to different volumes/concentrations or surgical contexts.
- Did not evaluate minimum effective SFICB volume for broader nerve coverage.
Future Directions: Dose-finding to determine minimal SFICB volume that reliably involves femoral and LFCN without motor deficits; pragmatic trials comparing block bundles for TKA analgesia and function.
BACKGROUND: Clinical evidence on obturator nerve involvement after supra-inguinal fascia iliaca compartment block (SFICB) is limited. This study aimed to investigate whether a 40-mL SFICB reliably anesthetizes the obturator nerve and whether the addition of a selective obturator nerve block (ONB) improves postoperative analgesia in patients undergoing total knee arthroplasty. METHODS: In this randomized, double-blind, active-controlled trial, 84 patients who underwent total knee arthroplasty were randomized to receive SFICB (40 mL of 0.5% ropivacaine) plus either active (10 mL of 0.5% ropivacaine) or placebo (10 mL of normal saline) ONBs. Spinal anesthesia and postoperative analgesia were standardized. Two primary outcomes were (1) the success rate of ONB, measured 45 min after block completion, and (2) equivalent intravenous morphine consumption during the first 24 h postoperatively, tested following a predefined fixed-sequence procedure. Secondary outcomes included post-block sensorimotor function, pain scores, rescue analgesic use, patient satisfaction, sleep quality, recovery quality, and adverse effects within 48 h postoperatively. RESULTS: The success rate of ONB was significantly higher in the ONB group than in the placebo group (97.6% vs 2.4%; risk difference, 95.2%; 95% confidence interval, 81.2%-98.0%; P < 0.001). Equivalent intravenous morphine consumption during the first 24 h postoperatively did not differ significantly between the ONB and placebo groups (6.8 [2.5, 11.5] vs 7.8 [4.6, 17.5] mg; median difference, -2.5; 95% confidence interval, -5.0 to 0.5; P = 0.156). No differences were observed in the secondary outcomes, except for a greater reduction in adductor strength in the ONB group. CONCLUSIONS: An SFICB with 40 mL of 0.5% ropivacaine rarely anesthetized the obturator nerve. The addition of a selective ONB did not improve postoperative analgesia or recovery quality within 48 h after total knee arthroplasty. Further studies are needed to define the minimum effective SFICB volume that reliably involves the femoral and lateral femoral cutaneous nerves. CLINICAL TRIAL REGISTRATION: ChiCTR2300073558.