GLP-1 and dual GIP/GLP-1 receptor agonists are known to cause delayed gastric emptying, which may increase the risk of residual gastric contents despite preoperative fasting (1):
Advice for healthcare professionals:
- glucagon-like peptide-1 (GLP-1) and dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 receptor agonists, such as the dual agonist tirzepatide, are known to slow gastric emptying, which is a recognised side effect of these medicines
- consider that patients taking these medicines who are undergoing surgeries or procedures with general anaesthesia or deep sedation may have residual gastric contents despite preoperative fasting
- anaesthetists should consider the potential risk of aspiration within their risk assessment of patients being treated with GLP-1 or dual GIP/GLP-1 receptor agonists for all indications and manage the aspiration risk, in line with usual anaesthetic practice
- anaesthetists should provide an individualised assessment of the aspiration risk. Within the risk assessment, consider the following points:
- that patients taking GLP-1 or dual GIP/GLP-1 receptor agonists who have underlying diabetic gastroparesis, as well as other comorbidities such as obesity or gastroesophageal reflux disease, and symptoms of delayed gastric emptying (such as nausea, vomiting, and abdominal pain) may be at higher risk of aspiration
- patients should be asked about whether they are taking GLP-1 or dual GIP/GLP-1 receptor agonists. Consider the possibility that patients may have purchased GLP-1 or dual GIP/GLP-1 receptor agonists for aesthetic weight loss and may not readily disclose this information unless directly asked. Be aware that private prescriptions may not always be included in the patient’s medical notes or drug history
- healthcare professionals should identify the increased risk of aspiration as early as possible before surgery and specifically at pre-assessment clinic before surgery
- remind patients to inform their healthcare teams and anaesthetists if they are on GLP-1 or dual GIP/GLP-1 receptor agonists
- report suspected adverse drug reactions associated with GLP-1 and dual GIP/GLP-1 receptor agonists, aspiration and other surgical complications on a Yellow Card
Reference:
- MHRA Safety Update volume 18, issue 6: January 2025: 1