What Is a Gastric Emptying Study?

The process by which food is excreted from the stomach into the duodenum is called gastric emptying. Gastric emptying is receiving more and more attention because it is involved in the pathophysiology of many diseases and has become one of the targets of intervention in drug metabolism.

Gastric emptying

The process by which food is excreted from the stomach into the duodenum is called gastric emptying. Gastric emptying is receiving more and more attention because it is involved in the pathophysiology of many diseases and has become one of the targets of intervention in drug metabolism.

The detection of gastric emptying generally includes intubation method, radiology method, absorption test, real-time ultrasound, radionuclide method and so on.

Chinese name

Gastric emptying

Foreign name

gastric emptying

Process

Stomach drains into duodenum

Depend on

Pressure difference across the pylorus

Influencing factors

Stomach food capacity,

The process of draining food from the stomach into the duodenum is called gastric emptying.

Stomach emptying depends on the pressure difference (direct motive force) on both sides of the pylorus. The increase in intragastric pressure caused by gastric movement is the motive force for gastric emptying (

(1) The effect of the amount of food in the stomach on the emptying rate: The contents of the stomach are used as a mechanical stimulus to expand the stomach, which causes the strengthening of gastric movement through the inner wall reflex or vagal-vagal reflex. Generally, the rate at which food is emptied from the stomach is proportional to the square root of the amount of crop left in the stomach.

(2) The effect of gastrin on gastric emptying: expansion irritation and certain components of food, mainly protein digestion products, can cause gastrointestinal gastrointestinal release of gastrin. In addition to promoting gastric acid secretion, gastrin also promotes gastric movement, but also enhances the contraction of the pyloric sphincter. The overall effect is to delay gastric emptying.

The specific process of gastric emptying: food stimulation of the gastric wall is the driving force to promote gastric emptying. When the pyloric sphincter is opened, gastric movement is strengthened, and the internal gastric pressure is greater than

There are currently 9 commonly used methods to detect gastric emptying function, such as intubation, radiology, absorption test, real-time ultrasound, radionuclide method and so on. Each has its own advantages and disadvantages, of which the radionuclide method is considered the current "gold standard" for detecting gastric emptying.

The intubation method commonly used for intubation is the dual sample concentration difference method. The specific method is to place a gastric tube after the test meal, first extract gastric juice as sample 1, and then inject a concentrated marker twice the sample volume. After mixing, Then take the same volume of gastric juice as sample 1 as sample 2. Based on the two sample concentrations, the amount of residual fluid in the stomach at that time was estimated. Repeat the above examinations at different time intervals to obtain the dynamic changes of gastric emptying. This method can accurately measure liquid gastric emptying, but because of the complicated operation, it is also an invasive test method, which is difficult for subjects to accept. With the application of nuclide and other methods, this method has been rarely used to detect human gastric emptying, but it can still be used to verify the accuracy of other methods.

Radiology Radiology is a classic and ancient method of examination. At present, we commonly use the barium capsule or barium method, which was established in 1984 by Feldman and others. They use a polyethylene tube to wrap the barium agent to make a certain size radiopaque marker. Number of markers to understand gastric emptying. It should be pointed out that different size markers represent gastric emptying in different physiological conditions. Radiology is a non-invasive method that can accurately detect gastric emptying of indigestible solid foods. It can also observe the small intestine and colon running time at the same time and understand the lower gastrointestinal motor function. However, it does not fully reflect the emptying of physiological digestive nutrients, and requires multiple exposures to X-rays, limiting inspections to certain limits.

The measurement of epigastric impedance includes the measurement of epigastric impedance (IE) and the application of potential tomography (APT). The former has many deficiencies and may be replaced by the latter. Here we mainly introduce the latter. The principle of APT imaging is: placing electrodes around the upper abdomen, two adjacent electrodes give a certain amount of alternating current one by one, and combining the upper abdomen impedance signals detected from the remaining 13 groups of adjacent electrodes each time to obtain a A tomographic image of the upper abdomen, the image shows the impedance distribution of the upper abdomen. After ingesting food, the dynamic detection can obtain a series of changes in APT images generated as the food is emptied. These images are then re-projected onto the first image to obtain the impedance change in the local area of the stomach. Empty situation. APT is an ideal non-invasive method with high accuracy, good repeatability, and little influence on the shape and structure of the stomach. It can be used to measure the emptying of liquids and granular solids. It should be noted that gastric acid secretion will affect the impedance of the gastric area, and the subject should take an acid inhibitor before the examination; duodenal reflux will also affect the results, which is not ideal for patients after major gastrectomy.