A gastric emptying study is a diagnostic test that measures how quickly food moves from your stomach into your small intestine. This medical procedure helps healthcare providers assess the muscular function of your stomach, known as gastric motility. It provides insights into whether food is emptying at a typical rate, too slowly, or too quickly.
Reasons for the Study
Healthcare providers recommend a gastric emptying study for symptoms suggesting issues with how food leaves the stomach. Common indicators include persistent nausea, recurrent vomiting, feeling full after small meals, abdominal bloating, discomfort after eating, unexplained weight loss, indigestion, and blood sugar fluctuations.
This study helps diagnose conditions where gastric emptying is either delayed or accelerated. Delayed gastric emptying, known as gastroparesis, means the stomach muscles are not working effectively to move food along. Conversely, rapid gastric emptying, or dumping syndrome, occurs when food passes too quickly into the small intestine. Identifying these patterns is important for developing an appropriate management plan.
Preparing for the Study
Preparation involves specific instructions for accurate results. You must avoid eating or drinking for at least four to six hours before the test, often requiring an overnight fast. Smoking should also be avoided on the morning of the test, as it can affect gastric emptying.
Medication adjustments are necessary. Certain drugs, such as opioids, anticholinergics, and some medications that influence gut motility (e.g., metoclopramide, erythromycin), should be paused for a few days prior to the study. Individuals with diabetes should discuss their insulin or oral medication regimen with their doctor, as blood glucose levels need to be managed carefully on the day of the test.
Conducting the Study
The study, typically gastric emptying scintigraphy (GES), involves consuming a standardized meal with a small, harmless radioactive tracer. This meal often consists of scrambled egg whites mixed with the tracer, toast, and water. Consume the entire tasteless meal within a short timeframe, usually ten minutes or less.
After eating, you will lie on a table while a specialized camera, known as a gamma camera, takes images of your abdomen. This camera detects the radiation emitted by the tracer, allowing medical professionals to track the food’s movement through your stomach. Images are captured at specific intervals over several hours, commonly at 30 minutes, one hour, two hours, and four hours after finishing the meal. During the waiting periods between scans, you may be able to leave the imaging room, but you must avoid eating or drinking anything further. The entire procedure typically lasts about four hours.
Interpreting Study Findings
Results are determined by measuring the percentage of the radioactive meal remaining in the stomach at each time point. These measurements are compared against established normal ranges to identify any deviations. A normal emptying pattern indicates that the stomach is moving food into the small intestine at an expected rate.
If the study shows significant food remaining in the stomach after four hours (typically over 10%), it suggests delayed gastric emptying, or gastroparesis. For instance, more than 60% retention at two hours or more than 10% retention at four hours is indicative of this condition. Conversely, if the stomach empties too quickly, such as more than 30% emptied at 30 minutes or more than 70% emptied at one hour, it points to rapid gastric emptying, often associated with dumping syndrome. These findings help healthcare providers understand the underlying issue and guide discussions regarding diagnosis and potential treatment strategies.