The effect of liberal fluid fasting on gastric fluid volume in patients undergoing painless gastroscopy: a randomized controlled study.

Objective: This study assessed the impact of liberalized clear liquid intake on gastric fluid volume (GFV) in patients undergoing painless gastroscopy.

Methods: 184 patients scheduled for elective sedation gastroscopy underwent 1:1 randomization to a liberal fasting group (n = 92) or a conventional fasting group (n = 92). The liberal protocol permitted clear liquid consumption (≤150 mL/h) until 30 minutes pre-procedure, whereas the conventional group maintained standard preoperative 2-hour fasting. GFV quantification was performed through dual-modality assessment (gastric ultrasound and endoscopic aspiration). The primary endpoint was GFV, with secondary outcomes comprising fasting duration modifications, protocol satisfaction, adverse event incidence, and inter-method agreement.

Results: No significant GFV differences emerged between groups as demonstrated by ultrasound or endoscopy. The liberal group demonstrated substantially shorter fasting durations and higher satisfaction scores, with comparable adverse event rates. Strong inter-method agreement was confirmed.

Conclusion: Liberal fasting achieves equivalent GFV control compared to conventional protocols while optimizing patient comfort, supporting its safe implementation in painless gastroscopy.