Daily Anesthesiology Research Analysis
Analyzed 123 papers and selected 3 impactful papers.
Summary
Analyzed 123 papers and selected 3 impactful articles.
Selected Articles
1. Ethological profiling defines pain behaviors and parses analgesia from drug side effects in a mouse model of complex regional pain syndrome.
Automated ethological profiling in a tibial fracture–cast CRPS model revealed robust, environment-dependent pain-like behaviors and showed that dexmedetomidine reduces mechanical allodynia primarily via central α2-adrenergic receptors. Notably, sedative effects were attenuated after injury, enabling separation of analgesia from sedation and highlighting a translational framework for α2-agonist evaluation.
Impact: This study advances mechanistic pain science by introducing scalable, automated behavioral phenotyping that disentangles analgesia from sedative confounds—critical for translating α2‑agonist effects to clinical pain management.
Clinical Implications: Findings support hypothesis-driven dosing and monitoring of dexmedetomidine where sympathetic activation may blunt sedation, and they encourage objective behavioral metrics to assess analgesia independently from sedation in translational studies.
Key Findings
- Automated LabGym analysis reliably categorized naturalistic and nocifensive behaviors after tibial fracture–cast injury across neutral and aversive environments.
- Dexmedetomidine reduced mechanical allodynia primarily through central α2-adrenergic receptors.
- Dexmedetomidine decreased locomotion, grooming, and rearing, with distinct effects on grooming quality/quantity in aversive settings.
- Sedative effects of dexmedetomidine were attenuated in injured versus uninjured mice, enabling separation of analgesia from sedation.
Methodological Strengths
- Use of a validated CRPS tibial fracture–cast model with both male and female mice and assessments in neutral and aversive contexts
- Automated, learning-based holistic behavior analysis (LabGym) reducing observer bias; pharmacologic dissection with α2-AR agonism/antagonism
Limitations
- Preclinical mouse study; generalizability to human CRPS and perioperative pain remains to be established
- Sample sizes and long-term durability of behavioral changes are not detailed in the abstract
Future Directions: Translate ethological metrics to clinical settings; test α2-agonist dosing paradigms that maximize analgesia while minimizing sedation; validate across other pain models and species.
Complex regional pain syndrome (CRPS) is a form of chronic postinjury pain affecting the extremities with contributions from the somatic and sympathetic nervous systems. The mouse tibial fracture-cast model was developed to enable preclinical study of CRPS mechanisms and guide condition-specific drug development. Given the inherent limitations of reflex pain measures in mice, we sought to holistically characterize pain-like behaviors in this model in neutral and aversive environments using quantitative behavior analysis with LabGym, a user-friendly automation tool that requires no special equipment or extensive computational resources. This study shows that tibial fracture-cast injury causes distinct changes in naturalistic and nocifensive behaviors in male and female mice in neutral and aversive environments, demonstrating reliable behavioral categorization using robust learning-based holistic assessment. As proof-of-concept for therapeutic testing, we leveraged this behavioral evaluation to characterize the peripheral vs central effects of targeting alpha-2 receptors (α2-AR) with dexmedetomidine (DEX), a selective α2-AR agonist with analgesic, sedative, and anxiolytic properties. We found that DEX reduced mechanical allodynia primarily through central α2-ARs. Dexmedetomidine also decreased motion metrics, grooming, and rearing in an open field and distinctly affected the quality and quantity of grooming in an aversive environment, and systemic α2-AR antagonists did not suppress this effect. Importantly, we also determined that the sedative effects of DEX were attenuated in injured compared with uninjured mice, consistent with known sympathetic nervous system activation in CRPS. Overall, this study highlights the use of automated behavioral testing to parse analgesia from sedation in a unique preclinical pain model.
2. Efficacy and Safety of Oliceridine for Patient-Controlled Intravenous Analgesia in Elderly Patients Undergoing Laparoscopic Radical Resection Surgery for Gastrointestinal Malignant Tumors: A Prospective Randomized Controlled Non-Inferiority Clinical Trial.
In older adults receiving PCIA after laparoscopic gastrointestinal cancer surgery, oliceridine achieved non-inferior analgesia to sufentanil while markedly lowering respiratory depression (2.3% vs 18.2%) and hypotension (11.4% vs 29.6%). Robustness across per-protocol and modified ITT analyses strengthens confidence in safety advantages.
Impact: Provides randomized, double-blind evidence supporting a safer μ‑opioid option for elderly PCIA, addressing high‑priority adverse events that constrain opioid use.
Clinical Implications: Clinicians may preferentially select oliceridine for elderly PCIA when respiratory and hemodynamic safety is paramount, with expectations of comparable analgesia and fewer adverse events.
Key Findings
- Non-inferior primary endpoint: resting pain AUC 0–48 h was similar between oliceridine and sufentanil.
- Marked reduction in respiratory depression with oliceridine (2.27%) versus sufentanil (18.18%).
- Lower hypotension with oliceridine (11.36%) versus sufentanil (29.55%).
- Findings consistent across per-protocol and modified intention-to-treat analyses.
Methodological Strengths
- Randomized, double-blind, non-inferiority design with prespecified margin and dual (PP and mITT) analyses
- Clinically relevant safety endpoints (respiratory depression, hypotension) in an elderly surgical population
Limitations
- Single-center study limits generalizability; sample size modest
- Analgesic background (ketorolac, tropisetron) may interact with opioid profiles and varies across institutions
Future Directions: Multicenter pragmatic trials comparing oliceridine with standard opioids across surgical types and frailty strata; cost-effectiveness and implementation studies.
BACKGROUND: Opioid-related adverse events are common with sufentanil-based patient-controlled intravenous analgesia after laparoscopic gastrointestinal cancer surgery in older adults. Oliceridine, a G protein-biased μ-opioid receptor agonist, may provide effective analgesia with fewer adverse events. METHODS: In this single-center, randomized, double-blind, non-inferiority trial (Tangdu Hospital, Xi'an, China), patients aged ≥60 years undergoing elective laparoscopic radical resection for gastrointestinal malignant tumors were allocated 1:1 to postoperative patient-controlled intravenous analgesia containing oliceridine (0.4 mg/kg) or sufentanil (2 μg/kg), combined with ketorolac and tropisetron, for 48 hours. The primary endpoint was the cumulative area under the curve for resting 0-10 visual analogue scale pain scores over 0-48 hours. The non-inferiority margin was prespecified as 20% of the mean AUC in the sufentanil group (18.3 points), a threshold based on prior studies and deemed clinically acceptable. RESULTS: Of 90 randomized patients, 88 received the study drug and were included in the analyses (44 per group); two patients were excluded as they never received the intervention. In the per‑protocol analysis, the cumulative resting pain area under the curve was 73.02±22.59 with sufentanil and 72.55±23.54 with oliceridine (between-group difference 0.48; 95% CI -9.30 to 10.26), meeting non-inferiority. A modified intention‑to‑treat analysis including all 88 treated patients yielded identical results, confirming robustness. Movement-evoked pain area under the curve was similar (difference 1.77; 95% CI -8.72 to 12.27). Respiratory depression occurred in 1/44 (2.27%) with oliceridine versus 8/44 (18.18%) with sufentanil, and hypotension in 5/44 (11.36%) versus 13/44 (29.55%). CONCLUSION: In elderly patients undergoing laparoscopic gastrointestinal cancer surgery, oliceridine provided non-inferior analgesia to sufentanil while significantly lowering the incidence of respiratory depression and hypotension. These findings suggest that oliceridine may be a preferred opioid option for PCIA when respiratory and hemodynamic safety are critical concerns. TRIAL REGISTRATION: ChiCTR2400090780.
3. Incidence of hemidiaphragmatic paralysis in superior trunk versus interscalene block upper limb surgeries: a systematic review, meta-analysis, and trial sequential analysis.
Across eight RCTs (n=597), superior trunk block cut complete hemidiaphragmatic paralysis risk to about one-tenth of that with interscalene block and also reduced Horner’s syndrome, without compromising analgesia or patient satisfaction. Trial sequential analysis supports robustness of these safety benefits.
Impact: Directly informs block selection by quantifying phrenic-sparing advantages of STB with preserved analgesia, addressing a common safety concern in shoulder anesthesia.
Clinical Implications: Consider STB as first-line for patients at risk of respiratory compromise (e.g., COPD, contralateral diaphragm dysfunction) where phrenic nerve sparing is critical, with no expected loss of analgesic efficacy.
Key Findings
- STB vs ISB: complete hemidiaphragmatic paralysis markedly reduced (RR 0.10; 95% CI 0.07–0.17; I2=0%).
- Horner’s syndrome significantly less frequent with STB (RR 0.06; 95% CI 0.01–0.24).
- No significant differences in postoperative pain, opioid use, patient satisfaction, or motor block duration.
- Trial sequential analysis supports sufficient evidence for the primary safety outcome.
Methodological Strengths
- PRISMA-compliant, PROSPERO-registered meta-analysis restricted to RCTs
- Inclusion of trial sequential analysis to assess accrued information size and control random errors
Limitations
- Potential heterogeneity in block techniques, volumes, and definitions across trials
- Generalizability to non-shoulder indications or varying ultrasound expertise may be limited
Future Directions: Head-to-head pragmatic trials comparing STB and ISB in high-risk respiratory populations; standardized protocols for STB technique and dosing.
BACKGROUND: Interscalene block (ISB) is widely used for upper limb surgery but frequently causes hemidiaphragmatic paralysis (HDP). Superior trunk block (STB) has emerged as a promising alternative that preserves phrenic nerve. This study aimed to evaluate whether STB is a safer option than ISB. METHODS: This systematic review and meta-analysis followed PRISMA guidelines and was registered in PROSPERO (CRD420250654685). Randomized controlled trials (RCTs) comparing STB and ISB in adults undergoing upper limb surgery and reporting HDP as the primary outcome were included. Secondary outcomes were postoperative pain, opioid consumption, motor block duration, patient satisfaction, and Horner's syndrome. Comprehensive searches were conducted through June 2025 in PubMed, Scopus, Embase, Cochrane, and Web of Science. Data were analyzed using a random-effects model in R, and trial sequential analysis was applied to assess statistical robustness. RESULTS: Eight RCTs involving 597 patients were included. Compared with ISB, STB significantly reduced the incidence of complete HDP (risk ratio [RR], 0.10; 95% confidence interval [CI], 0.07-0.17; I2 = 0%, P < 0.001) and Horner's syndrome (RR, 0.06; 95% CI, 0.01-0.24; I2 = 0%, P < 0.001). No significant differences were observed in opioid consumption (P = 0.262), pain scores (P = 0.661), patient satisfaction on a 0-10 scale (P = 0.117), or motor block duration (P = 0.624). CONCLUSIONS: STB provides postoperative analgesia comparable to ISB while significantly reducing the incidence of HDP and Horner's syndrome, supporting its role as a safer and effective alternative for shoulder surgery.