Control of anesthesia depth using continuous, non-invasive breath monitoring.
Research on Anesthesia Depth Control Strategy Based on Continuous and Non-invasive Monitoring of Exhaled Breath
This project tests whether continuous, non-invasive measurements of exhaled sevoflurane and propofol can predict BIS and guide anesthesia depth for adults having combined intravenous–inhalational surgery.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 500 (estimated) |
| Ages | 18 Years and up |
| Sex | All |
| Sponsor | Second Affiliated Hospital, School of Medicine, Zhejiang University Academic / other |
| Locations | 1 site (Hangzhou, Zhejiang) |
| Trial ID | NCT07272044 on ClinicalTrials.gov |
What this trial studies
This observational study will record real-time concentrations of exhaled sevoflurane and propofol in adults undergoing combined intravenous–inhalational anesthesia and compare them with simultaneous BIS values. Researchers will build prediction models to estimate BIS from breath concentrations and analyze the relationship between anesthetic levels and depth of anesthesia across patient subgroups. The method is intended as an alternative monitoring strategy for patients who cannot use standard BIS sensors. Recruitment is limited to adults (≥18 years) with ASA I–III status, expected surgery duration over one hour, and radial artery catheterization at a single hospital in Hangzhou.
Who should consider this trial
Good fit: Adults (≥18 years) undergoing combined intravenous–inhalational surgery lasting more than one hour, ASA I–III, who require BIS monitoring and have radial artery catheterization are the intended participants.
Not a fit: Patients with contraindications to general anesthesia, pregnant patients, those with severe psychiatric or neurologic disorders, long-term antiepileptic or psychotropic drug use, or who refuse participation are unlikely to benefit.
Why it matters
Potential benefit: If successful, this approach could let clinicians monitor and adjust anesthesia depth non-invasively when BIS is unavailable, improving safety and dosing precision.
How similar studies have performed: Previous work has linked inhalational anesthetic concentrations with BIS, but using continuous exhaled propofol measurements to predict BIS is relatively novel and not yet widely validated.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age ≥18 years old * ASA I-III * Expected duration of surgery \> 1 hour * Radial artery catheterization was performed * Patients requiring BIS monitoring. Exclusion Criteria: * Patients with contraindications to general anesthesia * mental disorder, unable to answer * long-term use of antiepileptic drugs and psychotropic drugs * pregnant patients * patients refused to participate * the investigator thought that the study was not suitable for inclusion * patients who did not wake up in PACU
Where this trial is running
Hangzhou, Zhejiang
- Second Affiliated Hospital, School of Medicine, Zhejiang University — Hangzhou, Zhejiang, China (Recruiting)
Study contacts
- Study coordinator: Fengjiang Zhang
- Email: zrzfj@edu.cn
- Phone: 18875213201
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.