Delayed Gastric Emptying
GLP-1 receptor agonists can delay gastric emptying, particularly during the early phase of treatment or during dose escalation. However, this effect often diminishes with long-term use due to physiologic adaptation. As a result, the degree of delayed gastric emptying varies significantly between patients and is influenced by medication dose, duration of therapy, and the presence of gastrointestinal symptoms. However, the risk of delayed stomach emptying varies from patient to patient.
Insufficient stomach emptying during perioperative care can complicate anesthetic management. In most asymptomatic patients receiving stable GLP-1 receptor agonist therapy, standard ASA fasting guidelines remain appropriate. However, additional evaluation may be warranted in patients with gastrointestinal symptoms or other risk factors for delayed gastric emptying. This requires a tailored approach that may involve extended fasting periods or the use of diagnostic tools such as gastric ultrasonography to assess stomach contents.
Aspiration and Regurgitation Risk
GLP-1 receptor agonists delay stomach emptying, which increases the risk of aspiration in the perioperative phase. Aspirating stomach contents into the lungs can cause serious pulmonary complications, such as chemical pneumonitis, aspiration pneumonia, and acute respiratory distress syndrome (ARDS). Patients experiencing gastrointestinal symptoms such as nausea, vomiting, or bloating are at risk, as these symptoms may indicate significant stomach contents remaining after fasting.
Several case reports and research have reported aspiration in patients using GLP-1 receptor agonists. For example, aspiration was reported in a recent study involving a patient on semaglutide who had fasted for more than 18 hours before surgery, and significant residual contents were seen by gastric ultrasonography, highlighting the need for caution in these patients.
Blood Glucose Level Changes
Although GLP-1 receptor agonist medications are not associated with hypoglycemia due to their glucose-dependent mechanism of action, the stress of surgery, combined with changes in diet and medication in the perioperative period, can alter glycemic control, necessitating close monitoring and adjustment of other antidiabetic medications.
