Bedside ultrasound assessment of gastric content: an observational study

Can J Anaesth. 2012 Apr;59(4):416-23. doi: 10.1007/s12630-011-9661-9. Epub 2012 Jan 4.


Purpose: There is a growing interest in the use of bedside ultrasonography to assess gastric content and volume. It has been suggested that the gastric antrum in particular can be assessed reliably by sonography. The aim of this observational study was to provide a qualitative description of the sonographic characteristics of the gastric antrum when the stomach is empty and following the ingestion of clear fluid, milk, and solid content.

Clinical features: Six healthy volunteers were examined on four different occasions (24 scanning sessions): following a period of eight hours of fast and following ingestion of 200 mL of apple juice, 200 mL of 2% milk, and a standard solid meal (sandwich and apple juice). Examinations were performed following a standardized scanning protocol by two clinical anesthesiologists with previous experience in gastric sonography. For each type of gastric content, the sonographic characteristics of the antrum and its content are described and illustrated with figures.

Conclusions: Bedside sonography can determine the nature of gastric content (nil, clear fluid, thick fluid/solid). This qualitative information by itself may be useful to assess risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

MeSH terms

  • Adult
  • Gastrointestinal Contents*
  • Humans
  • Pyloric Antrum / diagnostic imaging*
  • Ultrasonography