Clinical trial NCT06915558: Modulation of the Inflammatory Response in Bariatric Surgery
Official title: Modulation of the Inflammatory Response to Surgical Trauma: Comparison of Three Anesthetic Techniques in Bariatric Surgery Patients
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Obesity
Bariatric Surgery Candidate
Inflammation
Postoperative Pain
Opioid-Free Anesthesia
Heart Rate Variability
Keywords: Opioid-Free Anesthesia
Opioid-Based Anesthesia
Inflammatory Markers
Surgical Stress Response
heart rate variability
Lead sponsor: Hospital HM Nou Delfos
Sponsor class: OTHER
First posted: 2025-04-08
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: The study population consists of adult patients undergoing elective bariatric surgery at HM Nou Delfos Hospital. Patients will be selected according to specific inclusion and exclusion criteria to ensure homogeneous groups for the comparison of inflammatory response to different anesthetic techniques. All participants will undergo preoperative screening, intraoperative monitoring, and postoperative follow-up to evaluate primary and secondary outcomes.

Brief summary: This study will evaluate how different anesthesia techniques affect inflammation after bariatric surgery. Patients will be randomly assigned to receive one of three approaches: opioid-free anesthesia, intravenous anesthesia with opioids, or inhalational anesthesia with opioids.

The study will measure blood levels of inflammation-related substances (such as IL-6, CRP, cortisol, ESR , WBC and lactate) at several time points before and after surgery. Heart rate variability will also be monitored as an indicator of the body's stress response.

The results may help identify anesthesia strategies that reduce inflammation and improve recovery in patients undergoing bariatric surgery.

Detailed description: This is a prospective, randomized, double-blind, comparative observational study designed to assess the perioperative inflammatory response in patients undergoing bariatric surgery under three anesthetic techniques: opioid-free anesthesia (OFA), opioid-based intravenous anesthesia (OBA-IV), and opioid-based inhalational anesthesia (OBA-Inh).

A total of 90 patients scheduled for elective laparoscopic bariatric surgery will be enrolled and randomized using computer-generated allocation into three equal groups (n=30 each). Allocation concealment will be maintained using sealed opaque envelopes. Blinding will involve both the patients and outcome assessors; anesthesiologists administering the interventions will not be blinded due to the nature of the techniques.

The study's primary focus is to evaluate the perioperative modulation of inflammation through quantification of biomarkers including interleukin-6 (IL-6), C-reactive protein (CRP), serum cortisol, leukocyte count (WBC), erythrocyte sedimentation rate (ESR) and lactate. Heart rate variability (HRV) will be continuously monitored as a surrogate marker for autonomic modulation of the inflammatory response.

Biomarkers will be sampled at three time points: preoperative baseline (T0), at the end of surgery (T1), and 24 hours postoperatively (T2). HRV data will be collected from induction to the end of surgical intervention using a non invasive monitoring system with time- and frequency-domain analysis.

Secondary outcomes include intraoperative and postoperative analgesic consumption, pain intensity assessed by visual analog scale (VAS), sedation scores using the Ramsay Agitation-Sedation Scale (RASS), incidence of opioid-related side effects (nausea, vomiting, respiratory depression), patient satisfaction (via validated questionnaire), and length of hospital stay.

Sample size was calculated based on preliminary data detecting a clinically significant difference in IL-6 levels, assuming an alpha of 0.05 and power of 0.8. Data will be analyzed using ANOVA or Kruskal-Wallis test for continuous variables, chi-square for categorical variables, and multivariate regression models to adjust for potential confounders.

This study aims to identify anesthetic strategies that minimize systemic inflammation and autonomic dysregulation in the bariatric surgical population, with potential applications in broader surgical settings.

Eligibility criteria: Inclusion Criteria:

* Patients scheduled for bariatric surgery.
* Age 18-65 years.
* BMI ≥ 30 kg/m².
* ASA physical status II-III.

Exclusion Criteria:

* Pregnancy or breastfeeding.
* Chronic opioid use before surgery.
* Severe renal or hepatic failure.
* Uncontrolled psychiatric disorders.
* Significant intraoperative complications requiring protocol deviation.

Primary outcomes:
measure: Serum IL-6 Level
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
measure: C-reactive Protein (CRP) Level
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
measure: Serum Cortisol Level
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
measure: Heart Rate Variability (HRV) as an Inflammatory Marker
timeFrame: Collected continuosly from the induction of the anesthesia until the end of surgery
measure: Serum Lactate Level
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
measure: Erythrocyte Sedimentation Rate (ESR)
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
measure: Differential White blood Cell count (WBC).
timeFrame: Preoperative (baseline), immediately after surgery, and 24 hours post-surgery.
Secondary outcomes:
measure: Postoperative Pain Evaluation Using Visual Analog Scale (VAS)
timeFrame: hourly during the first 4 hours post surgery in the recovery area, and at 12 and 24 hours in the hospitalization ward
measure: Postoperative Sedation Level Using Ramsay Sedation Scale
timeFrame: immediately after surgery, and hourly during the first 4 hours in the recovery area, and at 12 and 24 hours in the hospitalization ward
measure: Incidence of Postoperative Complications
timeFrame: 24 hours post-surgery.
measure: Patient Satisfaction with Anesthetic Technique
timeFrame: 24 hours post-surgery.
Other outcomes:
Locations:
city: Barcelona
country: Spain
facility: Hospital HM Nou Delfos
Study officials:
affiliation: Hospital HM Nou Delfos
name: Gregory Contreras-Pérez, Anesthesiologist
role: PRINCIPAL_INVESTIGATOR
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