An Orogastric Tube (OGT) is a flexible tube passed through the mouth, down the esophagus, and into the stomach. This device provides a direct route into the gastrointestinal tract, used for administering nutrition, fluids, or medications when oral intake is insufficient. OGTs are frequently used in critically ill patients, especially neonates and infants, or in adults who are intubated or have facial trauma that prevents nasal tube placement. Ensuring the correct length is measured before insertion is necessary for patient safety and proper function.
Necessary Supplies and Initial Safety Checks
Gathering the correct equipment is necessary before initiating the procedure. Supplies typically include the appropriately sized OGT, a measuring tape, a 10 to 60 ml syringe, water-based lubricant, non-allergenic tape or a specialized securement device, and pH testing strips. The correct tube size is important; a larger bore is used for gastric decompression or drainage, while a finer bore is preferred for long-term feeding.
Initial safety checks require confirming the medical order for OGT placement, including the tube’s purpose and size. The patient should be positioned supine, with the head supported in a neutral, midline position to facilitate the natural path of the tube. Patients should not have been fed for 15 to 30 minutes prior to reduce the risk of vomiting and subsequent aspiration during the procedure. The tube must be inspected for integrity, confirming that it is intact and the exit ports near the tip are clear.
The Three-Point Measurement Technique
Determining the precise length for insertion minimizes the risk of the tube coiling in the esophagus or entering the lung. The standard anatomical landmark method, adapted from the Nasogastric Tube (NGT) technique, is a three-point measurement performed externally on the patient’s body.
The measurement begins at the patient’s mouth or lip, the entry point for the OGT. The tube is extended backward toward the earlobe, following the curve of the ear. The third point is found by continuing the tube downward toward the xiphoid process.
In some clinical settings, particularly for neonates and children, the Mouth-Ear-Mid-Umbilicus (MEMU) method is sometimes preferred. This alternative technique extends the tube to a point midway between the xiphoid process and the umbilicus. The measured length should correspond to the point where the tube’s distal tip will rest in the stomach, ensuring it is past the gastroesophageal junction.
Marking the Tube and Securing It Externally
Once the correct insertion length has been determined using the anatomical landmarks, a mark must be placed on the OGT. This is typically done using an indelible marker or noting the pre-printed numerical line that aligns with the measured distance. This mark serves as the target depth during insertion.
After the tube has been inserted to the target depth, it must be immediately secured to the patient’s cheek or face to prevent migration or dislodgement. Non-allergenic tape or a specialized securing device is used for external stabilization. Care must be taken to ensure the tape does not cover the measurement mark, allowing the external length to be monitored continually. Consistent documentation of the external length is necessary for subsequent checks for tube migration.
Verifying the Tube’s Final Position
Verifying the tube’s final position before use is the most important step. The most reliable method for confirming gastric placement is obtaining a chest and abdominal X-ray, which is considered the gold standard. Radiographic confirmation allows healthcare professionals to visualize the tube’s entire path and confirm the tip is within the stomach.
A bedside method for initial verification involves aspirating fluid from the tube and testing its pH level. Gastric aspirate is acidic, and a pH reading between 1 and 5.5 is indicative of correct placement in the stomach. A reading of 6 or higher suggests the tube may be positioned in the respiratory tract or the small intestine, or that the patient is taking acid-reducing medications.
Auscultation involves injecting a small volume of air into the tube while listening over the stomach with a stethoscope. While historically common, this technique is unreliable and should never be used as the sole method of confirmation. No feeding or medication should be administered until the tube’s location is verified by a reliable method, ideally pH testing or X-ray, to prevent inadvertent pulmonary administration.