Test performance of point-of-care ultrasound for gastric content

Objective: We sought to determine test performance characteristics of emergency physician ultrasound for the identification of gastric contents.

Methods: Subjects were randomized to fast for at least 10 h or to consume food and water. A sonologist blinded to the patient's status performed an ultrasound of the stomach 10 min after randomization and oral intake, if applicable. The sonologist recorded their interpretation of the study using three sonographic windows. Subsequently 2 emergency physicians reviewed images of each study and provided an interpretation of the examination. Test performance characteristics and inter-rater agreement were calculated.

Results: 45 gastric ultrasounds were performed. The sonologist had excellent sensitivity (92%; 95% CI 73%-99%) and specificity (85%; 95% CI 62%-92%). Expert review demonstrated excellent sensitivity but lower specificity. Inter-rater agreement was very good (κ = 0.64, 95%CI 0.5-0.78).

Conclusion: Emergency physician sonologists were sensitive but less specific at detecting stomach contents using gastric ultrasound.