A Gastrostomy tube (G-tube) is a feeding device that provides a direct pathway for nutrition, fluids, and medications into the stomach. The tube is inserted through a surgically created opening, known as a stoma. This method is used when a person is unable to safely consume adequate nutrients by mouth due to various medical conditions. Verifying the tube’s correct position within the stomach is a necessary safety measure to prevent serious complications before administering anything through it.
Preparing for the Placement Check
Checking G-tube placement begins with gathering the necessary equipment and positioning the individual appropriately. You will need a clean stethoscope, a 5 to 10 milliliter (mL) syringe, and a small, measured amount of air drawn into the syringe. Proper patient positioning is crucial as it affects the movement of air and the clarity of the sound you are listening for.
A semi-Fowler’s position, where the head of the bed is elevated to a 30 to 45-degree angle, is ideal for this procedure. This inclined posture helps stomach contents pool in the lower part of the stomach, making the auscultation process more effective. Locate the stoma site and identify the upper left quadrant of the abdomen, often called the epigastric region, where the stomach is primarily situated.
The diaphragm of the stethoscope should be placed directly onto the skin in this upper left area to ensure the clearest auditory feedback. The air-filled syringe should be prepared and ready to connect to the G-tube or its extension set before the check begins.
Performing the Air Bolus Technique
The air bolus technique is a bedside method used to check for internal tube positioning. This involves connecting the air-filled syringe to the G-tube’s port without introducing air prematurely. A volume of 5 to 10 mL is sufficient for an adult, while smaller volumes (2 to 3 mL) are used for infants and children.
Place the stethoscope firmly over the designated upper left quadrant of the abdomen. Maintaining this position is essential to clearly hear the sound of the air entering the stomach cavity. The air must be injected swiftly, but not forcefully, into the tube while simultaneously listening with the stethoscope.
The speed of the injection is important because it creates a distinct, sudden rush of air that generates a recognizable sound within the stomach. If the tube is correctly located, the air is directed into the stomach’s lumen, creating an audible event. This rapid injection is followed immediately by listening for the characteristic sound that confirms the tube’s tip is in the gastric space.
Understanding the Sounds of Proper Placement
When the G-tube is correctly positioned, the rapid injection of air produces a distinct sound heard through the stethoscope. This sound is often described as a clear, sharp “whoosh,” “pop,” or gurgling noise. The sound should be focused and immediate, correlating directly with the moment the air is pushed from the syringe.
This distinct sound occurs because the stomach is a hollow organ, allowing the air to resonate upon entry. This confirms that the tube’s distal tip is situated in the stomach rather than being displaced.
If the tube is dislodged, the sound may be absent, faint, or muffled. The characteristic sound will not be produced if the air is injected into the space between the stomach and abdominal wall, or if the tube has migrated outside the stomach. Hearing a sound over the lungs or chest area, instead of the stomach, is a strong indication of severe misplacement that requires immediate attention.
When to Seek Professional Confirmation
While the air bolus technique is a common practice, it is widely considered an unreliable standalone method for definitively confirming G-tube placement. Research indicates that the sound produced can sometimes be misleadingly similar even if the tube is misplaced, such as in the esophagus. For this reason, clinical settings prefer more reliable methods like X-ray confirmation or pH testing of aspirated fluid.
Stop the procedure immediately if you are unable to inject the air, or if the expected sound is absent or unclear. Signs of patient distress, such as coughing, gagging, or new abdominal pain during air injection, also signal potential misplacement. Significant leakage around the stoma site, especially with swelling, redness, or a foul odor, suggests a problem with the tube or the stoma tract.
If placement is uncertain or concerning symptoms are observed, do not administer feeds or medications. Secure the tube and immediately contact a healthcare professional or emergency services for further assessment, as these warning signs necessitate professional confirmation to prevent serious complications.