How to Verify Orogastric (OG) Tube Placement
Radiographic Confirmation is Mandatory
Every patient must undergo radiography (chest X-ray or abdominal X-ray) to confirm proper position of an OG tube before feeding is initiated. 1 This is the gold standard and only 100% reliable method for confirming tube placement. 2, 3
Why Bedside Methods Alone Are Inadequate
Auscultation is unreliable and should never be used as the sole confirmation method. 1 Bedside auscultatory techniques can be misleading because inappropriate tube locations—such as in the lung, in the pleural cavity after perforation, or coiled in the esophagus—may produce sounds that are misinterpreted as proper gastric position. 1, 2
Air injection into the tracheobronchial tree or pleural space can produce sounds indistinguishable from air injected into the gastrointestinal tract. 2
Misplacement rates for blindly placed gastric tubes range from 1.9% to 89.5% in adults and 20.9% to 43.5% in children. 2
Recommended Verification Algorithm
Step 1: Initial Placement Technique
Insert an 8-12F lubricated OG tube with the patient's head flexed while they ingest sips of water (if able) to assist passage into the stomach. 1
For extremely low birth-weight infants, combine the nose-ear-mid-umbilicus (NEMU) method with a birth weight-based method to reduce misplacement rates (from 53% to 34% for low placements). 4
Step 2: Immediate Bedside Assessment (Preliminary Only)
While awaiting radiographic confirmation, you may perform these adjunctive checks, but never rely on them alone:
pH testing of aspirate: In adults, pH and bilirubin of aspirate have been shown to reliably predict tube position with inexpensive bedside tests. 2 In children, only pH of aspirate has been shown reliable. 2
Visual inspection of aspirate: Examine characteristics of gastric contents. 2
Ultrasound may be useful in settings where X-ray is not readily available to detect misplaced tubes, though it lacks sufficient accuracy as a single confirmatory test (sensitivity 0.96-0.98 depending on method, but very low certainty evidence for specificity). 3
Step 3: Mandatory Radiographic Confirmation
Obtain chest X-ray or abdominal radiograph before initiating any feeding or medication administration. 1, 2
Verify the tube tip is positioned in the stomach, not above the diaphragm (too high), in the esophagus, in the lung, or near the pylorus (too low). 4
For jejunal tubes specifically, position should be confirmed by X-ray 8-12 hours after placement. 5
Critical Pitfalls to Avoid
Never start feeding based on auscultation alone—this has led to catastrophic complications including aspiration pneumonia from tubes misplaced in the trachea. 1, 2
Do not assume proper placement even if the patient tolerates the procedure well—asymptomatic misplacement occurs frequently. 1
Recheck tube position if there is any clinical concern about migration, after patient repositioning, or if the external tube length marking has changed. 1
For OG tubes placed for decompression rather than feeding, the same radiographic confirmation standards apply. 1
Special Considerations
In settings where X-ray facilities are unavailable or difficult to access, ultrasound combined with other confirmatory tests (pH testing, visual inspection) may be used, with sensitivity estimates ranging from 0.86 to 0.98, though specificity data are limited. 3
Blind bedside gastric tube placement is often successful and reproducible, so endoscopic or fluoroscopic placement is rarely necessary for simple OG tubes (as opposed to post-pyloric tubes). 1