Authors: Haas TE et al.
European Journal of Anaesthesiology 43(3): 207–216, March 2026,
This prospective, randomized pilot trial evaluated whether allowing low-risk adult surgical patients to drink clear fluids until being called to the operating room improves patient-centered outcomes compared with standard 2-hour fasting recommendations.
Background
Although guidelines permit clear liquids up to 2 hours before anesthesia, in practice fasting times often extend far beyond this due to scheduling inefficiencies and workflow habits. Prolonged fasting contributes to discomfort, thirst, headache, and dissatisfaction.
Study Design
174 adult patients with low aspiration risk were randomized into three groups:
• Control: Usual care (2-hour rule, but no active enforcement)
• Conservative intervention: Assistance to adhere closely to 2-hour fasting
• Liberal intervention: Allowed to drink clear liquids until called to the OR
Primary Outcome
Patient-reported thirst before anesthesia induction (none, moderate, severe).
Key Results
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Actual fasting times
Control median fasting: 5.38 h
Conservative: 3.00 h
Liberal: 1.97 h
Both interventions significantly shortened fasting duration versus control (P < 0.001).
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Preoperative thirst
Compared with control:
• Conservative OR 0.41 (P = 0.013)
• Liberal OR 0.21 (P < 0.001)
Clear dose–response pattern: shorter fasting → less thirst.
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Postoperative thirst
Reduced in the liberal group (OR 0.32, P = 0.009).
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Preoperative headache
Reduced in the liberal group (OR 0.24, P = 0.009).
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Safety
No adverse events were reported.
The study was not powered to detect aspiration differences.
Interpretation
This trial demonstrates:
• Standard practice often exceeds guideline fasting durations.
• Enforcing a true 2-hour fasting protocol improves patient comfort.
• Allowing drinking until OR call further improves thirst and headache outcomes.
• No safety signal was observed in this low-risk population.
The results suggest that prolonged fasting is more a logistical artifact than a physiologic necessity.
Clinical Implications
For low-risk elective cases:
• Allowing clear liquids until patient transfer to the OR may be safe and improves comfort.
• Active coordination is required to prevent drift beyond 2 hours.
• Liberalization may enhance patient experience metrics and satisfaction scores.
In high-throughput centers, formalized “drink until called” protocols could meaningfully reduce perioperative discomfort without increasing evident harm—though larger safety-focused trials are needed.
Key Points
• Liberal fluid intake reduced preoperative thirst and headache.
• Conservative adherence to 2-hour rule also improved comfort.
• No adverse events observed in low-risk patients.
• Patient-centered outcomes clearly favor shorter fasting.
• Trial supports rethinking traditional fasting workflows.
For anesthesia departments focused on patient experience, this study reinforces that small workflow changes may yield disproportionate benefits in patient comfort with minimal apparent downside.
Thank you to the European Journal of Anaesthesiology for allowing us to summarize and share this article.