Gastric Residual Volume Assessment by Gastric Ultrasound in Fasting Obese Patients: A Comparative Study

Influence of semaglutide use on the presence of residual gastric solids on gastric ultrasound: a prospective observational study in volunteers without obesity recently started on semaglutide

PURPOSE

Glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) have become increasingly popular as both diabetic and weight loss therapies. One effect of this class of medication is delayed gastric emptying, which may impact the risk of aspiration during anesthesia delivery.

METHODS

In this prospective study, we used gastric ultrasound to evaluate the presence of solid gastric contents in both supine and lateral positions after an eight-hour fast in those taking GLP-1RA compared with controls. Participants underwent a second ultrasound evaluation two hours later after drinking 12 fluid ounces of water (approximately 350 mL).

RESULTS

Twenty adults voluntarily enrolled, giving a total of ten participants in each group. In the supine position, 70% of semaglutide participants and 10% of control participants had solids present on gastric ultrasound (risk ratio [RR], 3.50; 95% confidence interval [CI], 1.26 to 9.65; P = 0.02.) In the lateral position, 90% of semaglutide participants and 20% of control participants had solids identified on gastric ultrasound (RR, 7.36; 95% CI, 1.13 to 47.7; P = 0.005). Two hours after drinking clear liquids, the two groups did not differ in the lateral position, but in the supine position, 90% of control group participants were rated as empty compared with only 30% of semaglutide group participants (P = 0.02).

CONCLUSIONS

This study provides preliminary evidence that GLP-1RAs may affect gastric emptying and residual gastric contents following an overnight fast and two hours after clear liquids, which may have implications for aspiration risk during anesthetic care.

Three-Dimensional Multi-detector Computed Tomography (3D-MDCT) Gastric Volumetry in Patients with obesity and Normal-Weight Individuals

BACKGROUND

Obesity is a widely prevalent medical and socioeconomic problem. Bariatric surgery is indicated for patients with clinically severe obesity. Reduction of gastric volume is an important factor that contributes to weight loss after laparscopic sleeve gastrectomy (LSG). The impact of the gastric volume on weight after LSG has been studied.

AIM OF THE STUDY

This study was designed to assess the gastric volume in patients with obesity prior to LSG and in the normal-weight patients, using three-dimensional multi-detector computer tomography (3D-MDCT), and to evaluate the potential correlation of the gastric volume with body mass index (BMI).

PATIENTS AND METHODS

A total of 100 patients were equally enrolled in two groups: one group for patients with obesity scheduled for LSG and another one for normal-weight patients scheduled for non-bariatric surgery. The study patients underwent 3D-MDCT gastric volumetry.

RESULTS

The gastric volume ranged from 525 to 1170 mL in patients with obesity and from 312 to 676 mL in the normal-weight group. Statistically significant difference was found between the two groups. Age, weight, and BMI were found to be predictors for the gastric volume in normal-weight patients only.

CONCLUSION

MDCT gastric volumetry is a feasible method to assess the stomach volume. Higher volumes were evident in patients with obesity. Age, weight, and BMI are predictors for the gastric volume in normal-weight patients with linear regression equations that could help during the preoperative planning of bariatric surgeries.