New Global Consensus Cuts Pre-Surgery Fasting Times to Protect Patients

Pre-operative fasting is a long-standing safety practice designed to reduce pulmonary aspiration risk during anaesthesia. However, real-world data have shown that patients routinely fast far longer than guidelines recommend — in some cases over 14 hours without food and 9 hours without fluids. This prolonged deprivation is now recognised as independently harmful, causing dehydration, anxiety, metabolic dysregulation, impaired immune response, delayed bowel recovery, and reduced muscle strength. The growing body of evidence prompted an international effort to update fasting guidance in a way that balances safety with patient wellbeing.

The consensus was developed through a systematic literature review followed by a structured three-round Delphi process involving 68 stakeholders from five continents. The panel was deliberately multidisciplinary, including anaesthetists, surgeons, physicians, nurses, and patient advocates, as well as representatives from international professional organisations. Thirteen draft recommendations were iteratively refined through the Delphi rounds until consensus was reached on eight final recommendations.

The core findings support continuing the established 6-hour pre-operative fast for solid food and non-clear liquids (8 hours after a heavy or fatty meal), but strongly encourage patients to consume clear liquids — including water, tea, black coffee, and juice without pulp — until 2 hours before the start of anaesthesia or sedation. Critically, the panel recommends that institutions develop and implement protocols allowing even more liberal clear liquid intake, potentially permitting consumption right up until patients are called for their procedure. Salivation stimulants such as chewing gum or boiled sweets may also be used until transfer. Post-operatively, oral intake should be resumed as soon as clinically feasible.

The consensus also acknowledges the role of preprocedural gastric ultrasound as a tool that trained providers can use to assess gastric contents and guide clinical decisions when uncertainty about aspiration risk exists — for example, in patients with delayed gastric emptying or other risk factors.

These recommendations represent a significant shift in philosophy: rather than defaulting to rigid nil-by-mouth orders from midnight, the guidance calls for patient-centred, evidence-based fasting that minimises unnecessary deprivation. Liberalised clear liquid protocols are supported by accumulating evidence that gastric emptying of clear fluids is rapid and that allowing them close to anaesthesia does not meaningfully increase aspiration risk in standard surgical populations. The panel acknowledges that special populations — including those with gastroparesis, obesity, or emergency surgery — require individualised assessment and are not fully addressed by these general recommendations.