Ultrasound Assessment for Comparison of Gastric Residual Volume After Ingestion of Carbohydrate Drink and Water in Obesity Class II and III Volunteers at Risk of Aspiration

Gastric ultrasound will be performed by the radiologist on each participant before the study and at 0, 10, 20, 30, 60, 90, 120 minutes after drinking in the position of head upright 45 degree with left lateral decubitus to evaluate the gastric residual volume and time to empty gastric antrum. If time to empty gastric antrum is extended, ultrasound will be serial performed at 150 and 180 minutes.

We will perform the point-of-care test of glucose before the study and at 60, and 120 minutes after drinking.

Hunger will be measured by a numeric rating scale(NRS) before drinking, 60 and 120 minutes after drinking. The Numeric Rating Scale(NRS) is used for the self-report measurement of hunger levels, defined by numbers from 0 to 10, where 0 represents the lowest level of hunger and 10 represents the highest.

Thirst will be measured by a numeric rating scale(NRS) before drinking, 60, and 120 minutes after drinking. The Numeric Rating Scale(NRS) is used for the self-report measurement of thirst levels, defined by numbers from 0 to 10, where 0 represents the lowest level of thirst and 10 represents the highest.

Nausea will be measured by a numeric rating scale(NRS) before drinking, 60, and 120 minutes after drinking. The Numeric Rating Scale(NRS) is used for the self-report measurement of nausea levels, defined by numbers from 0 to 10, where 0 represents the lowest level of nausea and 10 represents the highest.