Gastric ultrasound to assess the prokinetic efficacy of erythromycin in a patient taking glucagon‐like peptide‐1 receptor agonists

Glucagon-like peptide-1 receptor agonists slow gastric emptying and may increase aspiration risk. Recent guidelines suggest using prokinetic agents pre-operatively, but no studies have assessed the efficacy of erythromycin for this purpose. We present a 53-year-old man (weight 110 kg) taking liraglutide and undergoing elective knee arthroscopy. Despite 19 h of fasting and withholding liraglutide, gastric ultrasound revealed a grade 3 antrum with solid content. Intravenous erythromycin 300 mg was administered, causing transient gastrointestinal symptoms. A repeat ultrasound 15 min later showed reduced solid content, although the antrum was not convincingly empty. As the patient declined neuraxial anaesthesia without sedation, a modified rapid sequence induction was performed. An ultrasound scan at the completion of surgery confirmed an empty stomach, and recovery was uneventful. This is the first documented case using gastric ultrasound to assess the effect of erythromycin on a patient taking a glucagon-like peptide-1 receptor agonist. While erythromycin achieved its desired effect within 100 min, the optimal timing for prokinetic administration and subsequent ultrasound assessment remains uncertain. Gastric ultrasound may refine risk stratification and guide prokinetic use for these patients. Further research is needed to determine optimal erythromycin dosing, time to desired effect and side effects to optimise peri-operative management.