A post-pyloric feeding tube is a specialized medical device used to deliver nutrition, fluids, and medications directly into the small intestine, bypassing the stomach. This method, known as enteral nutrition, is reserved for patients who have a functional gut but cannot safely or effectively receive nutrients through the stomach. The tube is placed to ensure the patient receives adequate nutrition when oral consumption is impossible or dangerous. The selection of a post-pyloric tube is a clinical decision made when feeding into the stomach is unsafe or poorly tolerated.
Defining the Post Pyloric Tube Location and Function
The term “post-pyloric” describes the tube’s location relative to the pylorus, a muscular valve at the bottom of the stomach that controls food passage into the small intestine. A standard nasogastric tube ends in the stomach, but a post-pyloric tube is advanced past this muscle and into the small bowel.
The tip is positioned in either the duodenum (the first section of the small intestine) or the jejunum (the second section). Positioning the tube here allows the feeding formula to enter the digestive tract beyond the stomach’s control. The primary function is to provide a continuous pathway for nutrition when the stomach’s ability to regulate emptying is compromised.
Clinical Reasons for Choosing Post Pyloric Feeding
The decision to use a post-pyloric feeding tube (PPFT) is often driven by the need to mitigate the risk of pulmonary aspiration, which occurs when stomach contents are breathed into the lungs. Placing the tube tip past the pylorus creates a mechanical barrier that significantly reduces the likelihood of formula refluxing into the esophagus and airway. This is important for patients with neurological deficits, an impaired gag reflex, or those requiring mechanical ventilation.
A major indication is gastroparesis, a condition characterized by delayed gastric emptying. Bypassing the non-functional stomach ensures the formula is delivered directly to the small intestine, which may still be capable of normal absorption. This allows nutritional goals to be met without delay, and is also necessary in cases of severe, uncontrolled vomiting or gastric outlet obstruction.
In cases of acute pancreatitis, feeding into the jejunum is preferred because it allows the pancreas to “rest.” Food in the stomach and upper duodenum stimulates the release of pancreatic enzymes, which can worsen inflammation. Delivering the formula further down the small intestine minimizes this stimulation, supporting recovery while still providing necessary enteral nutrition.
Procedures for Tube Insertion and Verification
Achieving correct post-pyloric placement is more challenging than placing a tube in the stomach and requires specialized techniques. Bedside insertion can be done blindly or with an electromagnetic guidance system. This system uses an internal stylet with an electromagnetic tip to provide real-time tracking of the tube’s path, improving success rates and reducing the need for multiple X-rays.
If bedside placement is unsuccessful, the tube may be placed using endoscopic or fluoroscopic guidance. Endoscopic placement uses a flexible scope to visualize the pylorus and advance the tube into the small intestine. Fluoroscopic placement uses continuous X-ray imaging to guide the tube, often with the aid of a wire, with both methods boasting high success rates.
Verification of the final position is mandatory before feeding begins, with a plain chest and abdominal X-ray serving as the gold standard. The radiograph must confirm the tube tip has successfully crossed the pylorus and is located in the duodenum or jejunum. The image is checked to ensure the tube has not coiled in the stomach or been misplaced into the lungs, which could lead to severe complications.
Daily Management and Troubleshooting
Routine maintenance focuses on preventing clogs and managing the unique digestive challenges of small bowel feeding. Because these tubes are narrow and the small bowel has little storage capacity, continuous feeding via a pump is the most common method. This slow, steady infusion prevents the diarrhea and cramping that can occur from the rapid delivery of a large bolus of formula.
To maintain the tube’s patency, regular flushing with water is essential, typically 30 milliliters of warm water every four hours during continuous feeding, and before and after administering medications. Small-bore tubes are highly susceptible to clogging from sticky formula or improperly crushed medications. If a clog occurs, gentle flushing with warm water in a large syringe is the first step, avoiding forceful pressure that could damage or displace the tube.
Tube migration is a specific risk, as the small bowel’s natural peristaltic action can push the tube back into the stomach. Caregivers must regularly check the external length of the tube at the insertion site, as a change suggests internal displacement. Signs of intolerance, such as new or increased diarrhea, may also signal that the tube has migrated or that the continuous feeding rate is too fast.