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Observed preprocedural fasting duration and interventions intended to reduce them: A reference list-based review and
Stephanie Lam1, Maxime P Cannesson1, Antonia Osuna-Garcia2
1Department of Anesthesia, UCLA School of Medicine, USA.
American Journal of Surgery
|May 21, 2026
Summary
Despite guidelines, patients fast longer than recommended. Interventions to shorten preprocedural fasting have shown limited success, indicating a need for improved strategies.
Area of Science:
- Anesthesiology
- Patient Safety
- Clinical Practice Guidelines
Background:
- Current preprocedural fasting guidelines in the US have been established since 1999.
- Numerous studies indicate that patients frequently exceed recommended fasting durations.
- Observed fasting times often surpass guideline recommendations, impacting patient care.
Purpose of the Study:
- To conduct a comprehensive review of preprocedural fasting literature.
- To perform a meta-analysis on observed fasting times and interventions aimed at reducing them.
- To evaluate the effectiveness of strategies designed to shorten preprocedural fasting periods.
Main Methods:
- A systematic literature search was conducted across multiple databases.
- Search terms included "preoperative fasting" and "aspiration."
- Reference lists and citation networks were analyzed, with a final search on July 31, 2024.
Main Results:
- Data from 79 articles (60,112 patients) on observed fasting times and 25 articles (76,359 patients) on intervention outcomes were analyzed.
- Mean pediatric liquid fasting: 7.1 hours; solids: 12.2 hours.
- Mean adult liquid fasting: 10.3 hours; solids: 13.5 hours.
- Quality assurance interventions reduced fasting times, but patient education, policy changes, staff education, and text messaging did not.
Conclusions:
- Observed preprocedural fasting durations remain significantly longer than recommended, even after 25 years of guidelines.
- Most interventions aimed at reducing fasting times have proven ineffective.
- Current strategies are largely refractory to shortening preprocedural fasting durations.
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