Figure 3.

Study flow diagram and Perlas Model ‘Risk’ stratification. Patient gastric content was assigned a ‘Grade’ (0, 1, 2, solid/thick) based on qualitative content seen in the supine and right lateral decubitus (RLD) positions. This was further refined based on qualitative volume measurements in patients with clear liquid content (‘Grades’ 1 and 2). Risk status was then assigned, with ‘Low Risk’ being those with empty content or clear liquid content < 1.25 ml/kg, and ‘High Risk’ being those with solid/thick liquid content or clear liquid content > 1.25 ml/kg.