Effect of Fasting Recommendations Among Patients Using GLP-1 Receptor Agonists

Inclusion Criteria: * Age ≥18 years old at enrolment. * Have regularly administered any type of once-weekly GLP-1 RA medication for a period of at least one month prior to randomisation. * If allocated to follow standard fasting guidelines, willing to adhere to ASA and ANZCA preoperative fasting requirements. This requires participants to only consume clear liquids up to 2 hours, a light or low calorific meal up to 6 hours, and fasting from fried foods, fatty foods, or meat for at least 8 hours prior to the trial visit. * If allocated to follow a 24-hour clear liquid diet, willing to adhere to nothing-by-mouth (NPO) for solids and last intake of clear liquids no less than 2 hours prior to the trial visit. * Provide a signed and dated informed consent form for study participation in line with the requirements of the human research ethics committee (HREC) of the study site. Exclusion Criteria: Participants meeting any of the following criteria, indicative of abnormal anatomy and not validated by gastric ultrasound, will be excluded from this trial: * Has a recent history of gastrointestinal bleed within the previous 1 month from enrolment. * Has a history of previous lower oesophageal or gastric surgery. * Has a known abnormal upper gastrointestinal anatomy, including hiatus hernia or gastric tumours. In addition, participants meeting any the of following criteria will be excluded from this trial: * Participant reports having been previously diagnosed with a clinically significant gastric emptying abnormality such as gastroparesis. * Participant reports concomitant use of insulin. * Unable to assume the right lateral decubitus position required for gastric ultrasound assessment. * Participant has difficulty fully understanding PICF or study materials due to a primary language other than English.