Gastric decompression is a medical intervention designed to relieve pressure within the stomach by removing accumulated fluids and air. This process involves the temporary insertion of a tube, usually through the nose, into the stomach to create a controlled pathway for drainage. The goal is to empty the stomach contents, which helps prevent nausea, vomiting, and severe abdominal distention. This measure allows the digestive system to rest and recover from an underlying condition.
Conditions Requiring Decompression
The primary purpose of gastric decompression is to manage conditions causing a dangerous buildup of gas and fluid in the stomach and intestines. A major reason for this intervention is a bowel obstruction, where a mechanical blockage prevents the normal passage of contents. The stomach continues to produce secretions and the patient may swallow air, causing significant distention above the blockage. Decompression also addresses postoperative ileus, a temporary paralysis of the bowel’s muscular movement often occurring after abdominal surgery, which leads to a functional obstruction and content accumulation.
Decompression is also employed to manage acute gastric distention, a severe form of bloating that can put pressure on other organs, including the lungs. Removing the air and fluid significantly reduces the risk of pulmonary aspiration, a serious complication where stomach contents are inhaled into the lungs, especially in patients who are vomiting or have impaired consciousness. The tube may also be inserted to remove ingested toxins or poisons from the stomach, a process sometimes called gastric lavage. Furthermore, it can be a preparatory measure before certain types of upper gastrointestinal surgery or endoscopy to ensure the stomach is completely empty.
How the Procedure is Performed
Gastric decompression is most often achieved using a nasogastric (NG) tube, a thin, flexible tube inserted through one nostril, down the throat and esophagus, and into the stomach. The healthcare provider measures the correct length from the patient’s nose to the earlobe, and then down to the xiphoid process (breastbone). Proper lubrication is applied to minimize friction and discomfort during insertion. The patient is typically asked to swallow water or air as the tube reaches the back of the throat to guide it into the esophagus rather than the trachea.
Once the tube is in the stomach, its correct placement is confirmed, most reliably by a chest and abdominal X-ray. This visual verification of the tube’s tip location is important to prevent complications like mistaken placement into the airway. For decompression, a double-lumen tube, such as the Salem Sump, is frequently utilized. This design features one large lumen for content removal and a second, smaller lumen that acts as an air vent. The air vent prevents the suction port from collapsing the stomach wall and adhering to the gastric lining, which can cause irritation.
The tube is then connected to a suction device to actively remove the trapped air, gas, and fluid. This suction is usually set to a low, intermittent pressure to gently pull contents out without causing damage to the stomach tissue. Intermittent suction protects the gastric mucosa from prolonged contact with the suction port. The removal of these contents effectively decompresses the stomach, immediately relieving pressure and reducing the risk of vomiting.
Managing the Patient During Decompression
While the decompression tube is in place, patient management focuses on comfort, monitoring, and maintaining fluid balance. Because the tube passes through the nasal passage and throat, patients often experience discomfort and irritation, making frequent oral hygiene important. The tube is secured to the patient’s nose to prevent accidental dislodgement and minimize pressure on the nostril, which can lead to skin breakdown. The patient is typically required to fast (“nothing by mouth” or NPO) to ensure the digestive system rests completely and allows the decompression to work effectively.
The care team closely monitors the output from the decompression tube, noting the volume, color, and consistency of the drained fluid. Continuous removal of stomach contents, particularly gastric acid and electrolytes, can disrupt the body’s internal balance. Consequently, the patient’s fluid status and electrolyte levels (such as potassium and sodium) are regularly checked to prevent dehydration or metabolic imbalances, often requiring intravenous fluid replacement.
Decompression is discontinued when the underlying issue resolves, indicated by signs such as a significant decrease in drainage volume, the return of normal bowel sounds, or the patient passing gas or having a bowel movement. Before final removal, a clamp trial is sometimes performed, where the tube is temporarily clamped to see if the patient develops nausea or distention. If the patient tolerates the clamping, the nasogastric tube can be removed, a quick procedure that requires the patient to take a deep breath and hold it to close the airway.