ObesityPhase 4NCT07105839
Opioid-Free Versus Opioid-Based Anesthesia in Bariatric
A Phase 4 study testing Intraoperative rescue analgesia and Intraoperative rescue analgesia: in people with Obesity and Bariatric Surgery, run by Siirt Training and Research Hospital.
Trial summary
This study is designed as a prospective, randomized, controlled clinical trial. It will be conducted in the operating rooms of the University of Health Sciences, Diyarbakır Gazi Yaşargil Training and Research Hospital. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Obesity, Bariatric Surgery
- What is being tested?
- Intraoperative rescue analgesia and Intraoperative rescue analgesia:
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- No sites listed yet
- Study dates
- 20 Aug 2025to 1 Mar 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18-65 years
- BMI >35
- ASA class III-IV
- Elective bariatric surgery (e.g., sleeve gastrectomy)
- Written informed consent
Who cannot join
- Refusal to participate
- Severe cardiac/pulmonary/psychiatric illness
- Allergy to study drugs
- Conversion to emergency surgery
- Withdrawal at any point by patient or investigator
- -
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: A Prospective, Randomized Controlled Trial Comparing Opioid-Free and Opioid-Based Anesthesia in Morbidly Obese Patients Undergoing Bariatric Surgery
This study is designed as a prospective, randomized, controlled clinical trial. It will be conducted in the operating rooms of the University of Health Sciences, Diyarbakır Gazi Yaşargil Training and Research Hospital. Patients aged 18 to 65 years who are scheduled for elective bariatric surgery and meet the inclusion criteria (ASA physical status I-III) will be enrolled in the study.
Eligible patients will be informed both verbally and in writing during their preoperative anesthetic evaluation, and written informed consent will be obtained at least 24 hours prior to surgery.
Read more
Patients will be randomly assigned to one of two groups using computer-generated randomization:
Group O (Opioid group)
Group NO (Opioid-free group)
All patients will receive 40 mg IV pantoprazole and 4 mg IV ondansetron 30 minutes before surgery as preoperative medication. Standard ASA monitoring will be applied, and fasting guidelines will be followed. Depth of anesthesia will be monitored in all patients using BIS, and maintained within a target range of BIS 40-60 to ensure adequate depth with no response to surgical stimuli.
Read the detailed description
This study is designed as a prospective, randomized, controlled clinical trial. It will be conducted in the operating rooms of the University of Health Sciences, Diyarbakır Gazi Yaşargil Training and Research Hospital. Patients aged 18 to 65 years who are scheduled for elective bariatric surgery and meet the inclusion criteria (ASA physical status I-III) will be enrolled in the study.
Eligible patients will be informed both verbally and in writing during their preoperative anesthetic evaluation, and written informed consent will be obtained at least 24 hours prior to surgery.
Patients will be randomly assigned to one of two groups using computer-generated randomization:
Group O (Opioid group)
Group NO (Opioid-free group)
All patients will receive 40 mg IV pantoprazole and 4 mg IV ondansetron 30 minutes before surgery as preoperative medication. Standard ASA monitoring will be applied, and fasting guidelines will be followed. Depth of anesthesia will be monitored in all patients using BIS, and maintained within a target range of BIS 40-60 to ensure adequate depth with no response to surgical stimuli.
Anesthesia Protocol:
Group O (Opioid Group):
General anesthesia will be induced with 2 mg/kg propofol, 2 µg/kg fentanyl, and 0.6 mg/kg rocuronium based on ideal body weight (IBW). Maintenance will be achieved using remifentanil (Ultiva®) infusion at 0.1-0.3 µg/kg/min and 1 MAC sevoflurane. Following induction, all patients will receive a bilateral transversus abdominis plane (TAP) block under ultrasound guidance using 40 mL of 0.25% bupivacaine.
Group NO (Opioid-Free Group):
General anesthesia will be induced with 2 mg/kg propofol, 0.5 mg/kg ketamine, and 0.6 mg/kg rocuronium (IBW). Anesthesia will be maintained with dexmedetomidine infusion at 0.2-1.4 µg/kg/h and 1 MAC sevoflurane. Following induction, a bilateral TAP block will also be performed using 40 mL of 0.25% bupivacaine under ultrasound guidance.
Postoperative Analgesia Protocol:
During skin closure, all patients will receive 1 g IV paracetamol and 50 mg IV ketoprofen. At the end of surgery, neuromuscular blockade will be reversed using sugammadex, and patients will be safely extubated.
In the postoperative period, patients will be followed in the surgical ward for 48 hours with a standardized analgesic protocol:
1 g IV paracetamol every 6 hours
4 mg IV ondansetron every 8 hours
50 mg IV ketoprofen every 12 hours
Pain will be assessed using the Visual Analog Scale (VAS). If VAS ≥ 4, 100 mg IV tramadol will be administered as rescue analgesia, and all interventions will be documented in the patient records.
- Conditions
- Obesity, Bariatric Surgery
- Being tested
- Intraoperative rescue analgesia, Intraoperative rescue analgesia:
- Keywords
- Opioid-Free Anesthesia, Pain Management, Multimodal Analgesia, Quality of Recovery (QoR-15), TAP Block
- Medical subject headings
- Obesity, Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intraoperative rescue analgesiaDrug
If signs of inadequate analgesia occur (e.g., >20% increase in heart rate or blood pressure), IV remifentanil infusion rate will be titrated upward within the safety margin.
Intraoperative rescue analgesia:Drug
If signs of inadequate analgesia occur (e.g., >20% increase in heart rate or blood pressure), IV dexmedetomidine infusion rate will be titrated upward (up to maximum safe dose).
| Study group | Role | What they receive |
|---|---|---|
| Group O (Opioid Group) | Active comparator | Induction with: 2 mg/kg IV propofol, 2 μg/kg fentanyl, 0.6 mg/kg rocuronium (ideal body weight)
Maintenance:0.1-0.3 μg/kg/min IV remifentanil infusion and 1 MAC sevoflurane
Bilateral TAP block: 40 mL of 0.25% bupivacaine under ultrasound guidance Receives: Drug: Intraoperative rescue analgesia |
| Group NO (Opioid-Free Group) | Active comparator | Induction with: 2 mg/kg IV propofol, 0.5 mg/kg ketamine, 0.6 mg/kg rocuronium
Maintenance: 0.2-1.4 μg/kg/h IV dexmedetomidine and 1 MAC sevoflurane
Bilateral TAP block: 40 mL of 0.25% bupivacaine under ultrasound guidance Receives: Drug: Intraoperative rescue analgesia: |
What is being measured
The primary outcome is the main question the study is designed to answer.
Postoperative VAS pain scores
Measured: post-op 1.hour (H), 2.H, 3.H, 6.H, 12.H, 18.H, 24.H, 36.H and 48.H
QoR-15 score (Quality of Recovery)
Measured: 24 Hours and 48 Hours
Secondary outcomes (2)
Rescue analgesic requirement
IV tramadol
Measured: Within 48 hours post-op
Postoperative nausea and vomiting (PONV) incidence questionnaire
Measured: 48 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Aug 2025
- Study start20 Aug 2025 (estimated)
- Primary completion20 Jan 2026 (estimated)
- Study completion1 Mar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ObesityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Siirt Training and Research Hospital
- Sponsor type
- Other government
- Responsible party
- Principal investigator, ali kendal oğuz, Saglik Bilimleri Universitesi Gazi Yasargil Training and Research Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07105839
- Sponsor's protocol ID
- OBES-OFAN-2025-01
- Status last verified
- Jul 2025
- First submitted
- 30 Jul 2025
- Last updated
- 6 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Data sharing is currently under consideration. A final decision will be made after study completion and ethical approval.
Study at a glance
From the registry record, last updated by the sponsor on 6 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective, Randomized Controlled Trial Comparing Opioid-Free and Opioid-Based Anesthesia in Morbidly Obese Patients Undergoing Bariatric Surgery
- ClinicalTrials.gov ID
- NCT07105839
- Acronym / sponsor ID
- OBES-OFAN-2025-01
- Conditions
- Obesity, Bariatric Surgery
- Keywords
- Opioid-Free Anesthesia, Pain Management, Multimodal Analgesia, Quality of Recovery (QoR-15), TAP Block
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Siirt Training and Research HospitalOther government
- Study start
- 20 Aug 2025 (estimated)
- Primary completion
- 20 Jan 2026 (estimated)
- Study completion
- 1 Mar 2026 (estimated)
- First posted
- 6 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study is designed as a prospective, randomized, controlled clinical trial. It will be conducted in the operating rooms of the University of Health Sciences, Diyarbakır Gazi Yaşargil Training and Research Hospital. Patients aged 18 to 65 years who are scheduled for elective bariatric surgery and meet the inclusion criteria (ASA physical status I-III) will be enrolled in the study.
Eligible patients will be informed both verbally and in writing during their preoperative anesthetic evaluation, and written informed consent will be obtained at least 24 hours prior to surgery.
Patients will be randomly assigned to one of two groups using computer-generated randomization:
Group O (Opioid group)
Group NO (Opioid-free group)
All patients will receive 40 mg IV pantoprazole and 4 mg IV ondansetron 30 minutes before surgery as preoperative medication. Standard ASA monitoring will be applied, and fasting guidelines will be followed. Depth of anesthesia will be monitored in all patients using BIS, and maintained within a target range of BIS 40-60 to ensure adequate depth with no response to surgical stimuli.
Detailed description
This study is designed as a prospective, randomized, controlled clinical trial. It will be conducted in the operating rooms of the University of Health Sciences, Diyarbakır Gazi Yaşargil Training and Research Hospital. Patients aged 18 to 65 years who are scheduled for elective bariatric surgery and meet the inclusion criteria (ASA physical status I-III) will be enrolled in the study.
Eligible patients will be informed both verbally and in writing during their preoperative anesthetic evaluation, and written informed consent will be obtained at least 24 hours prior to surgery.
Patients will be randomly assigned to one of two groups using computer-generated randomization:
Group O (Opioid group)
Group NO (Opioid-free group)
All patients will receive 40 mg IV pantoprazole and 4 mg IV ondansetron 30 minutes before surgery as preoperative medication. Standard ASA monitoring will be applied, and fasting guidelines will be followed. Depth of anesthesia will be monitored in all patients using BIS, and maintained within a target range of BIS 40-60 to ensure adequate depth with no response to surgical stimuli.
Anesthesia Protocol:
Group O (Opioid Group):
General anesthesia will be induced with 2 mg/kg propofol, 2 µg/kg fentanyl, and 0.6 mg/kg rocuronium based on ideal body weight (IBW). Maintenance will be achieved using remifentanil (Ultiva®) infusion at 0.1-0.3 µg/kg/min and 1 MAC sevoflurane. Following induction, all patients will receive a bilateral transversus abdominis plane (TAP) block under ultrasound guidance using 40 mL of 0.25% bupivacaine.
Group NO (Opioid-Free Group):
General anesthesia will be induced with 2 mg/kg propofol, 0.5 mg/kg ketamine, and 0.6 mg/kg rocuronium (IBW). Anesthesia will be maintained with dexmedetomidine infusion at 0.2-1.4 µg/kg/h and 1 MAC sevoflurane. Following induction, a bilateral TAP block will also be performed using 40 mL of 0.25% bupivacaine under ultrasound guidance.
Postoperative Analgesia Protocol:
During skin closure, all patients will receive 1 g IV paracetamol and 50 mg IV ketoprofen. At the end of surgery, neuromuscular blockade will be reversed using sugammadex, and patients will be safely extubated.
In the postoperative period, patients will be followed in the surgical ward for 48 hours with a standardized analgesic protocol:
1 g IV paracetamol every 6 hours
4 mg IV ondansetron every 8 hours
50 mg IV ketoprofen every 12 hours
Pain will be assessed using the Visual Analog Scale (VAS). If VAS ≥ 4, 100 mg IV tramadol will be administered as rescue analgesia, and all interventions will be documented in the patient records.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group O (Opioid Group) | Active comparator | Drug: Intraoperative rescue analgesiaInduction with: 2 mg/kg IV propofol, 2 μg/kg fentanyl, 0.6 mg/kg rocuronium (ideal body weight) Maintenance:0.1-0.3 μg/kg/min IV remifentanil infusion and 1 MAC sevoflurane Bilateral TAP block: 40 mL of 0.25% bupivacaine under ultrasound guidance |
| Group NO (Opioid-Free Group) | Active comparator | Drug: Intraoperative rescue analgesia:Induction with: 2 mg/kg IV propofol, 0.5 mg/kg ketamine, 0.6 mg/kg rocuronium Maintenance: 0.2-1.4 μg/kg/h IV dexmedetomidine and 1 MAC sevoflurane Bilateral TAP block: 40 mL of 0.25% bupivacaine under ultrasound guidance |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Age 18-65 years
- BMI >35
- ASA class III-IV
- Elective bariatric surgery (e.g., sleeve gastrectomy)
- Written informed consent
Key exclusion criteria (6 listed)
- Refusal to participate
- Severe cardiac/pulmonary/psychiatric illness
- Allergy to study drugs
- Conversion to emergency surgery
- Withdrawal at any point by patient or investigator
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Intraoperative rescue analgesiaIf signs of inadequate analgesia occur (e.g., >20% increase in heart rate or blood pressure), IV remifentanil infusion rate will be titrated upward within the safety margin. | Drug | Group O (Opioid Group) |
| Intraoperative rescue analgesia:If signs of inadequate analgesia occur (e.g., >20% increase in heart rate or blood pressure), IV dexmedetomidine infusion rate will be titrated upward (up to maximum safe dose). | Drug | Group NO (Opioid-Free Group) |
Primary outcome
Postoperative VAS pain scores
Time frame: post-op 1.hour (H), 2.H, 3.H, 6.H, 12.H, 18.H, 24.H, 36.H and 48.H
QoR-15 score (Quality of Recovery)
Time frame: 24 Hours and 48 Hours
2 secondary outcomes
Rescue analgesic requirement
Time frame: Within 48 hours post-op
Postoperative nausea and vomiting (PONV) incidence questionnaire
Time frame: 48 hours
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Aug 2025.
- Individual participant dataSharing planned: Undecided. Data sharing is currently under consideration. A final decision will be made after study completion and ethical approval.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Intraoperative rescue analgesia and Intraoperative rescue analgesia: in people with Obesity and Bariatric Surgery, run by Siirt Training and Research Hospital.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 6 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact ali K oğuz, specialist Dr in Anestesiology (+905324683045, alikendal.oguz@sbu.edu.tr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Postoperative VAS pain scores (time frame: post-op 1.hour (H), 2.H, 3.H, 6.H, 12.H, 18.H, 24.H, 36.H and 48.H). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Aug 2025.