๐Ÿ›๏ธ Verified NIH Record โ€ข Updated 2026-04-02

The Million Anesthesia Cases Study (MACS) - a Cohort Study of Preoperative Fasting and Perioperative Outcomes (NCT07022951)

The Million Anesthesia Cases Study (MACS) - Retrospective and Prospective Characterization of Perioperative Fasting Practices and Their Effects on Clinical Outcomes

๐ŸŸข Recruiting Interventional Protocol ๐Ÿ“Š Observational Clinical Research Sponsor: Massachusetts General Hospital

๐Ÿฉบ Plain-English Summary (8th-Grade Level)

Perioperative fasting has historically been viewed as a low-risk intervention. However, preliminary data indicate that perioperative loss of nutrition and fluids is likely harmful. This study intends to characterize perioperative fasting practices and their potential effects on clinical outcomes through possible effects on patient well-being (anxiety, hunger, thirst), physiology (hypovolemia, hypotension), perioperative aspiration, etc. The research team hypothesized that in addition to known adverse effects on patients' well-being, prolonged preoperative fasting adversely affects circulating blood volume-related (hypotension, decreased urine output etc.) and glucose metabolism-related (e.g., hypo/hyperglycemia) perioperative physiology. The investigators will also test for an association between the duration of preoperative fasting and the risk of perioperative pulmonary aspiration. Additional knowledge on the potential adverse effects of preoperative fasting will inform preoperative fasting policies and research interventions that are relevant to hundreds of millions of patients subjected to preoperative/preprocedural fasting worldwide each year.

Who can join: Review the eligibility criteria below.

Location: Mass General Brigham Hospital Network of secondary, tertiary, and quaternary care hospitals โ€” Boston, Massachusetts

๐Ÿงช Interventions in This Study

  • Preoperative fasting (OTHER)

๐Ÿ“‹ "Do I Qualify?" โ€” 1-Minute Self Screener

Instant Checklist

Full eligibility criteria are available on the official NIH protocol. View the criteria โ†—

๐Ÿ“ All Participating Trial Locations (1 Sites)

  • Mass General Brigham Hospital Network of secondary, tertiary, and quaternary care hospitals โ€” Boston, Massachusetts

๐Ÿ“ž Contact the Study Coordinator

Phone: (617) 724-3292

Email: anagrebetsky@mgh.harvard.edu

Coordinator details come directly from the registered NIH protocol. Confirm the study is still recruiting before traveling.

๐Ÿ’ฐ Cost, Insurance & Patient Rights

  • 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
  • Routine Patient Care: Under federal law (ACA ยง 2709) and many state statutes, routine care costs are covered during participation.
  • Voluntary Participation: You may withdraw at any time without affecting your standard medical care.

Explore by condition: All Anesthesia clinical trials

๐Ÿ’ก How to Participate

  1. Check the checklist above to see if you may qualify.
  2. Contact the study coordinator using the phone/email above.
  3. Ask about the visit schedule, what is covered at no cost, and any travel support.
  4. Confirm with your own doctor before making a decision.
๐Ÿ›๏ธ View Official NIH Record โ†—