Million Anesthesia Cases: Preoperative fasting and perioperative outcomes
The Million Anesthesia Cases Study (MACS) - Retrospective and Prospective Characterization of Perioperative Fasting Practices and Their Effects on Clinical Outcomes
This project will see if longer pre-surgery fasting harms people having procedures with anesthesia by looking at symptoms like hunger and thirst, physiologic changes such as low blood pressure and blood sugar shifts, and risks like aspiration and nausea.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 1200000 (estimated) |
| Sex | All |
| Sponsor | Massachusetts General Hospital Academic / other |
| Locations | 1 site (Boston, Massachusetts) |
| Trial ID | NCT07022951 on ClinicalTrials.gov |
What this trial studies
This observational cohort will analyze perioperative records from the Mass General Brigham Epic electronic health record covering a large sample of cases where patients received general, regional, or sedated anesthesia. Investigators will measure duration of preoperative fasting and link it to patient-reported well-being (anxiety, hunger, thirst), physiologic markers (blood pressure, urine output, glucose values), and clinical events (perioperative aspiration, postoperative nausea/vomiting, hypoglycemia). Inclusion requires a diagnostic or therapeutic procedure with anesthesia and available Epic data; patients not receiving anesthesia or without Epic records will be excluded. The study aims to identify associations between fasting duration and adverse perioperative outcomes to inform safer fasting practices.
Who should consider this trial
Good fit: Ideal candidates are patients having diagnostic or therapeutic procedures under anesthesia at participating Mass General Brigham hospitals with their perioperative information recorded in Epic.
Not a fit: Patients who do not receive anesthesia or whose records are not available in the Epic system will be excluded and will not be represented by this study's results.
Why it matters
Potential benefit: If successful, the findings could reduce unnecessary fasting, improve patient comfort, and lower risks like hypotension, glucose disturbances, and aspiration by informing fasting guidelines.
How similar studies have performed: Smaller trials and guideline updates support shorter clear-fluid fasting to improve comfort without increasing aspiration, but large-scale evidence linking fasting duration to physiologic outcomes and aspiration risk is still limited.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Diagnostic or therapeutic procedure with anesthesia care (general anesthesia, regional anesthesia, sedation, or a combination of the above) Exclusion Criteria: * Not receiving anesthesia care * Lack of medical record data in Epic electronic medical record system
Where this trial is running
Boston, Massachusetts
- Mass General Brigham Hospital Network of secondary, tertiary, and quaternary care hospitals — Boston, Massachusetts, United States (Recruiting)
Study contacts
- Study coordinator: Alexander Nagrebetsky, MD, MSc
- Email: anagrebetsky@mgh.harvard.edu
- Phone: 617-724-3292
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.