Metformin before surgery and risk of nausea and vomiting after anesthesia.
Association Between Preoperative Metformin Exposure and Postoperative Nausea and Vomiting in Patients Undergoing General Anesthesia: a Prospective Observational Cohort Study
This project will see if people who take metformin before general anesthesia have different rates or severity of postoperative nausea and vomiting compared with people not on metformin.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 909 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Sixth Affiliated Hospital, Sun Yat-sen University Academic / other |
| Locations | 1 site (Guangzhou, Guangdong) |
| Trial ID | NCT07244575 on ClinicalTrials.gov |
What this trial studies
This is a prospective observational cohort of 909 adults having surgery under general anesthesia with endotracheal intubation at the Sixth Affiliated Hospital of Sun Yat-sen University. Participants already on metformin (n=303) will be compared with those not taking metformin (n=606) using structured postoperative surveys. The primary outcome is the incidence of postoperative nausea and vomiting (PONV) within 0–120 hours after surgery, and secondary outcomes include interval-specific incidence and severity, antiemetic use, and quality of recovery measured by the QoR-15. Data will be collected prospectively without altering routine perioperative care.
Who should consider this trial
Good fit: Adults (age ≥18) scheduled for elective surgery under general anesthesia with endotracheal intubation who can give informed consent and complete postoperative questionnaires are eligible.
Not a fit: Patients undergoing emergency surgery, those already taking medications with antiemetic effects, those with preoperative nausea or vomiting, or those unable to cooperate with questionnaires are unlikely to benefit from participation.
Why it matters
Potential benefit: If positive, the findings could help clarify whether preoperative metformin use is linked to less PONV and inform medication planning to improve recovery after anesthesia.
How similar studies have performed: This specific question is relatively novel with limited prior data on metformin reducing PONV, and randomized evidence is lacking.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion criteria 1. Voluntarily sign the informed consent form; 2. Age ≥ 18 years; 3. Patients who require surgical treatment under endotracheal intubation with general anesthesia as determined by the treating physician. Exclusion criteria 1. Emergency surgery; 2. Currently taking medications with established antiemetic effects (e.g., corticosteroids, antipsychotics) due to underlying medical conditions; 3. Cognitive impairment or psychiatric disorders that preclude cooperation with questionnaire assessments; 4. Anticipated inability to extubate the tracheal tube postoperatively, which would interfere with outcome assessment; 5. Presence of nausea and/or vomiting prior to surgery.
Where this trial is running
Guangzhou, Guangdong
- The Sixth Affiliated Hospital, Sun Yat-sen University — Guangzhou, Guangdong, China (Recruiting)
Study contacts
- Principal investigator: Yang Zhao, Dr — The Sixth Affiliated Hospital, Sun Yat-sen University
- Study coordinator: Yang Zhao, Doctor
- Email: zhaoy47@mail.sysu.edu.cn
- Phone: 0086-02038254070
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.