Daily Anesthesiology Research Analysis
Three impactful anesthesiology and pain research papers emerged: (1) an international consensus establishing a core outcome set of patient-reported instruments for perioperative pain, (2) a randomized multicenter study demonstrating 12-month durability of cooled radiofrequency ablation for sacroiliac joint pain, and (3) a pediatric randomized trial showing isotonic balanced fluids reduce hyponatremia risk in major neurosurgery albeit with minimal clinical effect. Together, they advance outcome s
Summary
Three impactful anesthesiology and pain research papers emerged: (1) an international consensus establishing a core outcome set of patient-reported instruments for perioperative pain, (2) a randomized multicenter study demonstrating 12-month durability of cooled radiofrequency ablation for sacroiliac joint pain, and (3) a pediatric randomized trial showing isotonic balanced fluids reduce hyponatremia risk in major neurosurgery albeit with minimal clinical effect. Together, they advance outcome standardization, durable interventional pain care, and safer perioperative fluid management.
Research Themes
- Standardizing perioperative pain outcomes with patient-reported measures
- Durable interventional pain therapies for spine/pelvic pain
- Perioperative fluid choice and electrolyte safety in pediatric neurosurgery
Selected Articles
1. A core outcome set of measurement instruments for assessing effectiveness and efficacy of perioperative pain management: results of the international IMI-PainCare PROMPT Delphi consensus process.
An international, multiprofessional Delphi process established a core set of patient-reported instruments to standardize outcome assessment in perioperative pain research. The set includes specific tools for pain intensity, pain interference with in-bed activities, procedure-specific physical function, self-efficacy, and opioid-related adverse events.
Impact: This work provides a standardized toolkit that will harmonize outcomes across trials and enable better meta-analyses and patient-centered research in perioperative pain. It is likely to influence study design, reporting, and regulatory/journal requirements.
Clinical Implications: Adopting this core outcome set can improve comparability across perioperative pain trials, guide instrument selection in protocols, and support value-based, patient-centered quality improvement in postoperative pain care.
Key Findings
- Defined a core set of PROM instruments covering pain intensity (average, worst, rest, activity-specific), pain interference with in-bed activities, procedure-specific physical function, self-efficacy, and opioid-related adverse events.
- Used COSMIN-based psychometric appraisal plus international Delphi consensus including stakeholders with lived experience.
- Concluded that routine use of the core set will harmonize outcomes and improve postoperative pain research and care.
Methodological Strengths
- Systematic literature searches and COSMIN-based psychometric evaluation.
- International, multiprofessional Delphi with inclusion of patient stakeholders and formal consensus meetings.
Limitations
- Implementation and cross-cultural validation across diverse surgical populations remain to be demonstrated.
- The core set focuses on PROMs and does not standardize clinician-reported or performance-based outcomes.
Future Directions: Prospective validation and uptake studies across procedures and countries; integration into trial registries, journal requirements, and perioperative quality programs.
BACKGROUND: Effective perioperative pain management is crucial to prevent patient suffering, delayed recovery, chronic postsurgical pain, and long-term opioid use. However, the heterogeneous use of outcomes in studies complicates evidence synthesis and might not accurately reflect the experiences of individual patients. We initiated a consensus process to establish a core outcome set (COS) of patient-reported outcome measures (PROMs) in postoperative pain, building upon the earlier consensus on a COS of domains. METHODS: Potential PROMs were identified via systematic literature searches for the domains pain intensity (with subdomains at rest and during activity), physical function, self-efficacy, and adverse events, followed by appraisal of psychometric properties according to the COnsensus-based Standards for the selection of health Measurement INstruments methodology. Then, a consensus meeting was convened, followed by a Delphi process with an international, multiprofessional panel of stakeholders, including those with lived experience. A conclusive consensus meeting approved the final COS of PROMs. RESULTS: The final COS consists of one unidimensional numerical rating scale for assessing pain intensity on average, worst pain intensity, pain intensity at rest, and procedure-specific pain intensity during activity; one unidimensional scale for pain interfering with activities in bed; one procedure-specific scale for assessing physical function; the IMI-PainCare PROMPT adaptation of the Arthritis Self-Efficacy Scale for assessing self-efficacy; and the IMI-PainCare PROMPT adaptation of the Opioid-Related Symptom Distress Scale for assessing adverse events. CONCLUSIONS: Comprehensive use of a core outcome set will help harmonise outcome assessment, facilitate comparisons between studies, promote patient-centred research, and improve postoperative pain care.
2. Cooled radiofrequency ablation provides extended clinical utility in the management of chronic sacroiliac joint pain: 12-month follow-up results from the observational phase of a randomized, multicenter, comparative-effectiveness crossover study.
In patients with injection-confirmed sacroiliac joint pain, cooled radiofrequency ablation produced sustained 12-month pain reduction (mean NRS 6.4 to 3.5; ~57% responders) and improvements in quality of life and disability, with similar benefits in crossover patients. No serious CRFA-related adverse events were reported.
Impact: Provides multicenter, randomized comparative-effectiveness evidence with 12-month durability supporting CRFA as a disease-modifying option for SIJ pain. This can influence payer coverage, clinical pathways, and guideline recommendations.
Clinical Implications: For injection-confirmed SIJ pain, CRFA can be considered earlier in the pathway for patients responding to prognostic blocks, with expectations of 12-month benefit and low serious adverse event risk.
Key Findings
- Mean pain NRS decreased from 6.4±1.4 to 3.5±2.6 at 12 months in the randomized CRFA cohort; 57.4% met responder criteria.
- Crossover patients achieved similar 12-month improvements (mean NRS 6.1±1.5 to 3.4±2.5; ~55.6% responders).
- Clinically meaningful gains in EQ-5D-5L (+0.22±0.27 CRFA; +0.21±0.33 XO) and ODI (−12.4%±14.7 CRFA; −13.7%±17.1 XO); no serious CRFA-related adverse events.
Methodological Strengths
- Randomized, multicenter comparative-effectiveness design with predefined responder criteria.
- Injection-confirmed diagnosis and requirement for prognostic lateral branch block responders enhance patient selection validity.
Limitations
- Observational 12-month extension with crossover complicates strict between-group comparisons and may introduce selection bias.
- Lack of sham control limits inference about placebo effects.
Future Directions: Head-to-head trials versus alternative interventional options, cost-effectiveness analyses, and subgroup analyses to identify predictors of sustained response.
INTRODUCTION: Sacroiliac joint (SIJ) pain comprises up to 30% of cases of mechanical low back pain (LBP), the leading cause of disability worldwide. Despite sacral lateral branch cooled radiofrequency ablation (CRFA) showing efficacy in clinical trials, there is a lack of comparative-effectiveness long-term follow-up. METHODS: In this randomized, multicenter, comparative-effectiveness study, 210 patients with injection-confirmed SIJ pain who responded to prognostic lateral branch blocks were randomly assigned to receive CRFA of the L5 dorsal ramus and S1-S3/4 lateral branches or standard medical management (SMM) consisting of pharmacotherapy, physical therapy, injections, and integrative therapies. Patients were followed up at 1, 3, 6, 9, and 12 months, with participants reporting unsatisfactory SMM outcomes being allowed to crossover (XO) and receive CRFA at 3 months. The primary outcome measure was the mean change in average LBP score on a 0-10 Numeric Rating Scale (NRS), with secondary outcomes including measures of quality of life (QoL) and function. A responder was defined as a participant who experienced a ≥30% or ≥2-point decrease in average daily NRS pain score coupled with a score ≥5 out of 7 (moderately better) on the Patient Global Impression of Change scale. RESULTS: At 12 months, the mean NRS pain score declined from a baseline of 6.4±1.4 to 3.5±2.6, with 57.4% (35/61) of participants in the randomized CRFA cohort experiencing a ≥2-point or 30% decrease in average LBP from baseline. In the crossover cohort, 35/63 (55.6%) subjects had the same experience 12 months following the XO procedure; in the XO group, the mean LBP decreased from 6.1±1.5 to 3.4±2.5. Patients also experienced clinically meaningful improvements in QoL via EuroQoL-5D-5L at 12 months (mean change of +0.22±0.27 in the originally-treated CRFA group and +0.21±0.33 in the XO group). Oswestry Disability Index (ODI) scores also improved by 12.4%±14.7 (CRFA) and 13.7%±17.1 (XO) from baseline at study-end. No serious adverse events related to the CRFA procedure were reported. CONCLUSION: CRFA in patients with SIJ pain provided clinically significant and sustained improvements for 12 months following a single CRFA treatment, regardless of previous SMM treatment. TRIAL REGISTRATION NUMBER: NCT03601949.
3. Intraoperative isotonic balanced versus hypotonic crystalloids on postoperative sodium homeostasis in small children undergoing major neurosurgery: a randomized controlled trial.
In small children undergoing major neurosurgery, intraoperative isotonic balanced fluids attenuated postoperative sodium decreases and reduced hyponatremia compared to hypotonic fluids, though differences were statistically significant but clinically small. Some patients on isotonic fluids experienced >5 mmol/L sodium variation; no symptomatic events occurred.
Impact: This registered RCT addresses a common yet understudied pediatric anesthetic question, providing evidence to guide maintenance fluid choice and electrolyte monitoring in high-risk neurosurgical cases.
Clinical Implications: Consider isotonic balanced solutions to mitigate hyponatremia risk in small children undergoing major neurosurgery, while proactively monitoring for potentially excessive sodium swings even with short infusions.
Key Findings
- Isotonic balanced fluids led to smaller postoperative sodium decreases than 0.2% hypotonic fluids at end of surgery (−1.4±3.6 vs −4.6±3.5 mmol/L; P<0.001) and at 24 h (−1.2±4.8 vs −3.4±2.5 mmol/L; P=0.028).
- Hyponatremia was less frequent with isotonic fluids from immediate postoperative to 24 h; however, 25% of isotonic patients and 15% of hypotonic patients had sodium variation >5 mmol/L.
- No neurologic symptoms or circulatory overload occurred; isotonic group had higher hemoglobin and less diuresis at 48 h.
Methodological Strengths
- Randomized controlled design with trial registration (ChiCTR2100046539).
- Serial electrolyte measurements up to 6 days postoperatively in a defined pediatric neurosurgical population.
Limitations
- Modest sample size (n=80) limits power for clinical outcomes.
- Findings show statistically significant but clinically small differences; generalizability beyond major neurosurgery and to older children is uncertain.
Future Directions: Larger multicenter trials powered for clinical endpoints (neurologic outcomes, ICU/hospital LOS) and stratified by age and surgical type; protocols for monitoring and mitigating sodium variability.
BACKGROUND: Whether intraoperative isotonic balanced maintenance fluid is associated with less variation in sodium homeostasis in small children undergoing major neurosurgery remains unknown. METHODS: Patients aged up to 6 years undergoing major neurosurgery were randomly assigned to receive either isotonic balanced solution (IB) or 0.2% hypotonic solution (H) as intraoperative maintenance fluid. Serum electrolyte levels were measured from preoperative baseline to 6 d following surgery. RESULTS: Eighty patients were included in the primary analysis. Serum sodium change was significantly less in the IB patients from the end of surgery continuing to 24 h following surgery (at the end of surgery: -1.4 ± 3.6 versus - 4.6 ± 3.5 mmol/l, P < 0.001; 24 h post: -1.2 ± 4.8 versus - 3.4 ± 2.5 mmol/l, P = 0.028). Twenty (50%) of the IB patients and 25 (63%) of the H patients had serum sodium change > 2.5 mmol/l 24 h following surgery (6.0 ± 3.4 versus 4.8 ± 2.1 mmol/l), with 13 (33%) of the IB patients and 25 (63%) of the H patients having sodium decrease > 2.5 mmol/l (6.4 ± 3.7 versus 4.8 ± 2.1 mmol/l) (P = 0.007). Seven patients in group IB experienced an increase in blood sodium levels exceeding 2.5 mmol/l (median, 4.1 [range 2.7 ∼ 9.2] mmol/l). Notably, 10 (25%) of the IB patients and 6 (15%) of the H patients had sodium variation > 5 mmol/l (median, 8.5 [range 5.1 ∼ 14.6] versus 7.2 [range 5.5 ∼ 11.1] mmol/l). Immediately following surgery till 24 h postoperatively, hyponatremia was less observed in the IB patients compared with that in the H patients. The IB patients had higher hemoglobin levels and less diuresis 48 h postoperatively. No symptoms including altered mental status, seizure, and circulatory overload were observed in all patients. CONCLUSION: Intraoperative isotonic balanced solution infusion resulted in statistically but not clinically minimal variation of sodium homeostasis and hemoglobin level postoperatively in small children undergoing major neurosurgery, compared to the use hypotonic solution. Potentially excessive sodium fluctuation following isotonic balanced maintenance fluid infusion should be cautioned, even for a brief period of infusion. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ). REGISTRATION NUMBER: ChiCTR2100046539. Registration date: May 21, 2021. Principal investigator: Lin-Lin Song.