A percutaneous endoscopic gastrostomy (PEG) tube is a feeding device placed through the abdominal wall directly into the stomach. This tube provides nutrition, fluids, and medications when a person is unable to swallow safely or consume enough by mouth. Since the tube is used multiple times daily, verifying its correct location in the stomach before every use is necessary to ensure patient safety and prevent serious complications.
The Purpose of Routine PEG Tube Checks
Verifying the tube’s correct placement is mandatory because a misplaced tube can cause severe complications. The internal tip can migrate out of the stomach into the abdominal cavity or the lungs, requiring a check before every administration of feed or medication. If contents are administered into a migrated tube, they can enter the peritoneal cavity, potentially causing peritonitis. If the tube is positioned in the respiratory tract, administering feed could lead to aspiration pneumonia.
Initial placement is verified by a medical professional, often using an X-ray. However, routine, daily checks fall to caregivers or trained patients. These ongoing checks are necessary because the tube can inadvertently shift due to coughing, vomiting, or pulling. Confirming the tube is securely in place ensures the internal tip remains within the stomach lining.
The Essential First Step: External Tube Assessment
The initial check involves a visual and physical assessment of the tube’s external components and the skin around the insertion site. Caregivers should inspect the stoma for signs of irritation or movement, such as redness, swelling, pain, or fluid leakage, which may indicate inflammation or tube migration.
Next, examine the external marking and length of the tube. A baseline measurement, typically a centimeter marking where the tube exits the skin, is established after initial placement. The current measurement must be compared to this recorded baseline to detect inward or outward migration. Any change in external length suggests the internal tip may have moved from its proper gastric location.
Finally, assess the external retention disk or bumper. This device prevents the tube from migrating inward or outward. The disk should be snug against the skin, but not so tight that it causes excessive pressure or poor circulation, which can lead to complications like tissue erosion. If any part of this external assessment suggests a problem, the tube must not be used.
Internal Verification Methods
Aspiration and Visual Assessment
Once the external check is complete, confirm the tube’s internal location by attempting to withdraw a small amount of fluid, known as aspiration. Using a syringe, a caregiver slowly pulls back the plunger until 0.5 to 1.0 milliliter of fluid appears. The color and consistency of this aspirate provide clues about the tube’s location.
Gastric aspirate typically appears cloudy, green, tan, or off-white, and may occasionally look brown or bloody. If the withdrawn fluid is clear or has a yellowish, watery consistency, the tube may have migrated into the small intestine. Difficulty aspirating any fluid may suggest the tube is blocked or its tip is pressed against the stomach wall.
pH Testing
The most reliable routine method for confirming gastric placement is testing the acidity of the aspirated fluid using pH indicator strips. Gastric fluid is highly acidic due to hydrochloric acid, resulting in a low pH reading. A pH value between 1 and 5.5 confirms the tube tip is located within the stomach.
If the pH strip registers a reading of 6 or higher, the tube may be misplaced, as respiratory secretions and small intestine fluids are typically less acidic. Medications like antacids or continuous feeding can temporarily raise the stomach’s pH, potentially causing a false reading. If this occurs, wait at least one hour without administering anything through the tube before retesting the pH.
Air Auscultation Caveat
Air auscultation involves injecting a small amount of air into the tube while listening over the stomach with a stethoscope for a “whooshing” sound. This method is no longer considered dependable for confirming tube placement. The sound of air entering the stomach can be misleading because it does not reliably differentiate between air entering the stomach, the esophagus, or the lungs. Therefore, this technique should not be used as the sole method of verification.
Actions to Take When Placement is Uncertain
If any part of the verification process, including external measurement or pH testing, indicates potential tube misplacement, all activity must stop immediately. Cease the administration of feeding, fluids, or medications, and do not flush the tube with water. Flushing a misplaced tube could push contents into the abdominal cavity or lungs.
Contact the supervising healthcare professional, such as the registered nurse or physician, to report the uncertain placement. Clear documentation of the specific finding, such as a change in external length or a pH reading of 7.0, is essential. If the patient exhibits signs of distress, including coughing, difficulty breathing, or sudden abdominal pain, seek immediate medical attention. The tube must remain unused until a healthcare professional confirms the correct positioning, often through an X-ray.