Perioperative aspiration of gastric contents is a rare but serious adverse event. The risk of aspiration can be estimated by perioperative evaluation of stomach contents with ultrasound using a validated technique and scoring system. A lack of knowledge or familiarity is frequently cited by anesthesia providers as a rationale for not performing perioperative ultrasound assessments. The purpose of this study is to determine whether novice ultrasonography users (medical students, undergraduates, or inexperienced anesthesiologists) can be effectively taught a technique to evaluate stomach contents as compared to experts in ultrasonography.

This study will be conducted in two arms. For part 1, we will evaluate the efficacy of the self-taught course at producing accurate reads among novice ultrasound users on ideal, cooperative, adult subjects. For part 2, we will evaluate the effectiveness of the course through an identical study that uses clinical pediatric patients as subjects.

Using available literature and established standards for gastric ultrasound, a 15-minute ultrasound training video course will be designed that gives instruction on ultrasound orientation, use, and the antral scoring system of gastric contents. Ten novice ultrasound users will be selected by study personnel on a volunteer basis from a pool of undergraduate students, medical students, and inexperienced anesthesiologists acting as research interns.

For Part 1, 30 healthy adult volunteers with unknown gastric-content status will be recruited to serve as scanning subjects. For Part 2 (which will only begin after successful completion of Part 1), 30 patients will be recruited from pediatric hospital populations undergoing surgery in the preoperative area or the in- patient unit.

Each novice will assess the gastric contents of 6 subjects (3 in Part 1 and 3 in Part 2) using the clinical algorithm for gastric ultrasound and aspiration risk assessment - giving an antral grade for each subject (a score of 0-2). Each novice ultrasound assessment will be video recorded. In the weeks following this evaluation, expert ultrasonographers will observe each video and give their own scores for each subject using the antral grading system.

Inclusion Criteria:

Patients must:

1. be between ages of 2-60 years of age
2. have parental consent for children 2-17 years of age, or if the participant is 18 years or older, the participant must sign the ICF for them self as an adult
3. undergoing interventional radiology procedures under general anesthesia or located at an inpatient/outpatient facility at LPCH if they are a pediatric patient
4. must be over 18 years of age if a healthy volunteer

Exclusion Criteria:

1. Patients undergoing emergent surgical procedures
2. BMI greater than 24

All data will be de-identified. Data will be used collectively for research analysis.