This study compares two different anesthesia techniques in patients with obesity undergoing bariatric surgery: one that includes opioids (OBA), and one that avoids them completely (OFA). The main goal is to determine whether avoiding opioids during surgery leads to lower postoperative morphine requirements and fewer side effects. Researchers reviewed medical records of 70 patients who had bariatric surgery between June 2022 and December 2023 at a hospital in Spain. The study evaluates pain levels, sedation, complications, and total morphine use in the first 48 hours after surgery.

This is a single-center, retrospective, observational cohort study conducted at Hospital HM Nou Delfos (Barcelona, Spain). The aim is to compare postoperative opioid requirements and outcomes in patients with morbid obesity undergoing laparoscopic bariatric surgery, according to the intraoperative anesthesia technique used.

Two anesthetic strategies were evaluated:

Opioid-Free Anesthesia (OFA): Total intravenous anesthesia (TIVA) without opioids, using agents such as propofol, ketamine, dexmedetomidine, lidocaine and magnesium.

Opioid-Based Anesthesia (OBA): TIVA including opioids, following institutional standards.

Medical records of 70 patients (35 in each group) who underwent surgery between June 2022 and December 2023 were analyzed. Key data extracted included demographics, surgical duration, anesthetic drugs used, intraoperative complications, pain scores (VAS at 1, 2, 4, 24, and 48 hours), sedation levels (RAMSAY scale), adverse effects (e.g., nausea, vomiting, ileus, hypotension), and morphine consumption.

The primary outcome is total morphine use within the first 48 hours postoperatively. Secondary outcomes include pain scores, adverse events, time to awakening, and hospital length of stay. Statistical analysis was performed using descriptive and inferential methods, including regression models adjusted for age, sex, BMI, and comorbidities.

This study provides real-world evidence on the clinical impact of opioid-free anesthesia in bariatric patients, aiming to improve perioperative safety and enhance postoperative recovery.

Inclusion Criteria Age between 18 and 65 years

Body Mass Index (BMI) ≥ 30 kg/m²

ASA physical status II or III

Underwent laparoscopic bariatric surgery under general anesthesia at HM Nou Delfos

Surgery performed between June 1, 2022 and December 31, 2023

Exclusion Criteria Pregnancy or breastfeeding

Chronic pain patients on high-dose opioids

Known allergy to any anesthetic drug used in the study

Severe hepatic (e.g., cirrhosis with portal hypertension) or renal insufficiency

Untreated coagulopathy

Active alcohol or drug abuse

Uncontrolled or severe psychiatric illness

Intraoperative complications requiring deviation from planned anesthetic technique

Postoperative morphine use exceeding institutional norms for bariatric surgery

Adult patients (18-65 years) with obesity (BMI ≥ 30 kg/m²) classified as ASA II-III, who underwent laparoscopic bariatric surgery under general anesthesia at HM Nou Delfos between June 2022 and December 2023. Patients were retrospectively assigned to one of two groups based on the anesthetic technique used: opioid-free anesthesia (OFA) or opioid-based anesthesia (OBA).

This is a retrospective study involving patient health records. Due to ethical and privacy regulations, individual participant data cannot be shared publicly. Access is restricted to the research team as approved by the ethics committee.