When fasted is not empty: a retrospective cohort study of gastric content in fasted surgical patientsdagger

Background: Perioperative aspiration leads to significant morbidity and mortality. Point-of-care gastric ultrasound is an emerging tool to assess gastric content at the bedside. Methods: We performed a retrospective cohort study of baseline gastric content on fasted elective surgical patients. The primary outcome was the incidence of full stomach (solid content or >1.5 ml kg-1 of clear fluid). Secondary outcomes included: gastric volume distribution (entire cohort, each antral grade); the association between gastric fullness, fasting intervals, and co-morbidities; anaesthetic management changes and incidence of aspiration. Results: We identified 538 patients. Thirty-two patients (6.2%) presented with a full stomach. Nine of these (1.7%) had solid content and 23 (4.5%) had clear fluid >1.5 ml kg-1. An empty stomach was documented in 480 (89.8%) patients. The examination was inconclusive in the remaining 20 patients (5.0%). As expected, increasing antral grade was correlated with larger antral cross-sectional area and higher gastric volume (P