Daily Anesthesiology Research Analysis
Three anesthesiology-relevant studies stand out today: a randomized trial shows low-dose esketamine at induction halves postoperative delirium in anxious older adults after gastrointestinal tumor surgery; a systematic review/meta-analysis confirms preoperative anxiety is associated with higher chronic post-surgical pain; and a double-blind RCT demonstrates intranasal dexmedetomidine improves objective and subjective sleep quality on the first postoperative night after laparoscopic gynecologic su
Summary
Three anesthesiology-relevant studies stand out today: a randomized trial shows low-dose esketamine at induction halves postoperative delirium in anxious older adults after gastrointestinal tumor surgery; a systematic review/meta-analysis confirms preoperative anxiety is associated with higher chronic post-surgical pain; and a double-blind RCT demonstrates intranasal dexmedetomidine improves objective and subjective sleep quality on the first postoperative night after laparoscopic gynecologic surgery.
Research Themes
- Perioperative neurocognitive disorders and NMDA receptor modulation
- Psychological risk factors for chronic post-surgical pain
- Non-opioid strategies to enhance postoperative sleep and recovery
Selected Articles
1. Effects of Esketamine on Postoperative Delirium and Postoperative Cognitive Function in Elderly Gastrointestinal Tumor Patients with Preoperative Anxiety.
In elderly patients (60–80 years) with preoperative anxiety undergoing gastrointestinal tumor surgery, a single low-dose esketamine bolus (0.25 mg/kg) at induction halved postoperative delirium over 7 days and improved early postoperative MMSE scores compared with placebo. Safety signals in hemodynamics were monitored; analgesic needs and anxiety scores were secondary endpoints.
Impact: This randomized trial provides actionable evidence that peri-induction NMDA modulation can reduce postoperative delirium in a high-risk subgroup (elderly with preoperative anxiety). It offers a feasible, single-dose intervention with measurable cognitive benefits.
Clinical Implications: Consider low-dose esketamine at induction for elderly anxious patients at high risk of postoperative delirium, with appropriate monitoring for hemodynamics and neuropsychiatric effects. Integrate into multimodal delirium prevention pathways.
Key Findings
- Randomized comparison showed lower 7-day POD incidence with esketamine vs placebo (24% vs 48%).
- Early postoperative cognition (MMSE, days 1–7) improved in the esketamine group.
- Trial assessed secondary outcomes including hemodynamic adverse events, anxiety, pain scores, and analgesic use.
Methodological Strengths
- Randomized controlled design with clearly defined primary outcomes (POD incidence, MMSE).
- Targeted high-risk population (elderly with preoperative anxiety), enhancing clinical applicability.
Limitations
- Single-center study with modest sample size (n=100).
- Blinding procedures and detailed adverse event profiles are not fully described in the abstract.
Future Directions: Multicenter, adequately powered RCTs to validate efficacy, define optimal dosing/timing, characterize safety in diverse populations, and assess longer-term cognitive and functional outcomes.
PURPOSE: The aim of this study is to investigate the effects of administering low-dose esketamine during anesthesia induction on the occurrence of postoperative delirium (POD) and postoperative cognitive function in elderly patients with preoperative anxiety. PATIENTS AND METHODS: Elderly patients aged 60-80 years and with preoperative anxiety who were undergoing surgery for gastrointestinal tumors were enrolled. The patients were randomly divided into an esketamine group or a placebo group. Upon intravenous induction of general anesthesia, the placebo group received normal saline, while the esketamine group received a subanesthetic dose (0.25 mg/kg) of esketamine. The primary outcome was the incidence of POD and the Mini-Mental State Examination (MMSE) score within 7 days after the operation (d1 to d7). Secondary outcomes included perioperative hemodynamic adverse events, postoperative anxiety, postoperative pain score, and analgesic consumption. RESULTS: 118 patients were screened for eligibility, and 100 were recruited and analyzed. The incidence of POD within 7 days after surgery in the esketamine group was significantly lower than the placebo group (24.00% vs 48.00%, CONCLUSION: In elderly patients with preoperative anxiety who undergo gastrointestinal tumor surgery, administering a low-dose intravenous esketamine injection (0.25 mg/kg) during anesthesia induction can decrease the incidence of POD and improve early postoperative cognitive function.
2. The association between preoperative anxiety and chronic post-surgical pain after general anaesthesia, a systematic review and meta-analysis.
Across 23 studies, higher preoperative anxiety was associated with greater chronic post-surgical pain (standardized mean difference 0.31), translating to approximately 0.34 higher numeric rating scale pain. Findings were robust to subgroup analyses, though heterogeneity was high.
Impact: This DORA-aligned synthesis clarifies preoperative anxiety as a modifiable risk factor for chronic post-surgical pain, strengthening the rationale for perioperative psychological screening and targeted interventions.
Clinical Implications: Implement routine anxiety screening preoperatively and integrate psychological interventions (e.g., CBT, relaxation) within multimodal analgesia pathways to reduce CPSP risk. Consider stratifying trials by baseline anxiety.
Key Findings
- Meta-analysis of 23 studies found a positive association between preoperative anxiety and CPSP (SMD 0.31; 95% CI 0.20–0.41).
- Translation indicated a 0.34-point increase in NRS pain for patients with preoperative anxiety.
- High heterogeneity persisted but subgroup analyses did not change the overall association; protocol registered in PROSPERO.
Methodological Strengths
- PRISMA-compliant systematic review with risk-of-bias assessment and PROSPERO registration.
- Use of validated anxiety measures and CPSP assessed at ≥3 months.
Limitations
- High heterogeneity and potential residual confounding across observational studies.
- Limited granularity on types/timing of anxiety interventions in source studies.
Future Directions: Prospective trials targeting preoperative anxiety with standardized interventions and CPSP endpoints; mechanistic studies linking anxiety, central sensitization, and long-term pain trajectories.
BACKGROUND: Chronic post-surgical pain (CPSP) is a burden for both patients and healthcare, yet current treatment options are insufficient. Previous studies indicate preoperative anxiety as a risk factor for developing CPSP, yet no high-quality review exists. This study aims to systematically review the relationship between increased preoperative anxiety and the incidence of new CPSP. METHODS: Four databases were used to identify relevant studies for a systematic review and meta-analysis. Inclusion criteria included adult patients undergoing surgical procedures under general anaesthesia, measuring preoperative anxiety with validated tools, and postoperative pain at least 3 months after surgery. Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed, and a risk of bias analysis was performed. RESULTS: Of the 233 studies retrieved, 26 studies were included in the systematic review. Following risk of bias analysis, 23 papers were included in the meta-analysis. A correlation was found between preoperative anxiety and CPSP, with a standardised mean difference of 0.31 (95% confidence interval 0.20-0.41). High heterogeneity was observed, which was attributed to several possible confounding factors. Subgroup analysis did not alter this outcome. When translating the outcome to a relevant scale, we observed an increase in numeric rating scale pain of 0.34 for patients experiencing preoperative anxiety. CONCLUSIONS: There is moderate-quality evidence indicating a positive association between preoperative anxiety and CPSP, where an increase in preoperative anxiety correlates with an increased incidence of CPSP. More research is needed to identify specific patients that would benefit from treating preoperative anxiety and thus potentially preventing CPSP. SYSTEMATIC REVIEW PROTOCOL: PROSPERO (CRD42024513479).
3. Effects of Dexmedetomidine Nasal Sprays on Postoperative Sleep Quality in Patients Who Underwent Laparoscopic Gynaecological Surgery: A Single-Centre, Double-Blind, Randomized Controlled Study.
In a double-blind RCT (n=144 analyzed), intranasal dexmedetomidine 50 μg administered 30 minutes before sleep on the first postoperative night improved objective sleep metrics (total, deep, and REM sleep) and subjective sleep quality (AIS) versus saline after laparoscopic gynecologic surgery.
Impact: Addresses a frequent but under-treated recovery issue—postoperative sleep disruption—using a noninvasive, low-dose alpha-2 agonist with favorable safety, supporting broader multimodal recovery strategies.
Clinical Implications: Consider intranasal dexmedetomidine (50 μg) on the first postoperative night to improve sleep after minimally invasive gynecologic procedures, with monitoring for bradycardia or hypotension as per alpha-2 agonist effects.
Key Findings
- Intranasal dexmedetomidine improved total sleep time, deep sleep, and REM sleep compared to saline.
- Subjective sleep quality (Athens Insomnia Scale) improved on the first postoperative night.
- Trial was double-blind and randomized; 144 patients were included in the final analysis.
Methodological Strengths
- Double-blind randomized controlled design with objective and subjective sleep endpoints.
- Standardized dosing and timing (50 μg, 30 minutes before sleep).
Limitations
- Single-center design limits generalizability; effect durability beyond the first night is unknown.
- Abstract lacks detailed adverse event rates; heart rate changes noted as secondary outcomes.
Future Directions: Replicate in multicenter settings, define dose-response and optimal timing, test across surgical types, and assess impact on pain, delirium, and next-day functional recovery.
BACKGROUND: Dexmedetomidine nasal sprays is effective for perioperative sedation, analgesia, and anxiolysis. Nevertheless, its impact on postoperative sleep quality along with the optimal dosage and overall efficacy remains unclear in patients undergoing laparoscopic gynecological surgery. METHODS: A total of 150 adult patients undergoing laparoscopic gynecological surgery were enrolled, with 144 included in the final analysis. Patients in the dexmedetomidine (Dex) group received 50 µg of intranasal dexmedetomidine 30 minutes before sleep on the first postoperative night, while the control group received an equivalent volume of saline. Primary outcomes included objective sleep parameters (sleep duration, deep sleep duration, REM sleep duration and light sleep duration) measured via a portable sleep monitor, as well as subjective sleep parameters assessed by Athens Insomnia Scale (AIS) and Numerical Rating Scale (NRS) scores one night before and on the first night after surgery. Secondary outcomes comprised postoperative pain measured by VAS, nausea and vomiting, and average heart rate. RESULTS: The sleep duration, deep sleep duration and REM sleep duration of patients in the control group decreased after laparoscopic gynaecological surgery (vs preoperative control group, CONCLUSION: Dexmedetomidine nasal sprays improved postoperative sleep quality in patients who underwent laparoscopic gynaecological surgery. TRIAL REGISTRATION: Chinese Clinical Trial Registry (clinical trial number: ChiCTR2400080181).