[Influence of Preoperative Fluid Intake on Perioperative Outcome]

Despite guideline recommendations allowing clear fluids up to two hours before anaesthesia, prolonged preoperative fasting remains common. This article summarises current evidence and clinical practice regarding preoperative fluid intake and highlights implications for perioperative management based on selective literature review.Excessive fluid restriction promotes dehydration and is associated with increased risk of delirium, haemodynamic instability, and acute kidney injury; patient comfort (thirst, anxiety, PONV, pain) is also impaired. Consistent application of the two-hour rule or liberal strategies ("Sip til send") shortens fasting times, improves thirst and well-being, and is not associated with higher rates of regurgitation or aspiration in current evidence. Intravenous fluid boluses immediately before induction provide short-term stabilisation but do not replace early, preferably oral, rehydration. Vulnerable populations, including paediatric and geriatric patients, appear to benefit most.Preoperative fluid management should aim to reliably prevent dehydration through patient-centred, evidence-based, and pragmatic strategy. Emerging data suggest that liberal fluid intake regimens may better achieve these objectives than the currently endorsed two-hour restriction from the outdated 2011 ESAIC guideline. Further well-designed implementation studies and adequately powered randomised trials are warranted to confirm safety and effectiveness.