How to confirm Ryle's (nasogastric) tube placement?

How to Confirm Ryle's (Nasogastric) Tube Placement

Radiographic confirmation with chest X-ray or abdominal X-ray is mandatory before initiating any feeding or medication administration through a nasogastric tube, as this is the only 100% reliable method for confirming proper gastric position. 1, 2

Primary Confirmation Method

• Obtain radiographic imaging (chest or abdominal X-ray) immediately after insertion to verify the tube tip is positioned in the stomach before any feeding begins. 1, 2
• This is the gold standard method with 100% reliability for detecting proper placement and preventing catastrophic complications such as aspiration pneumonia from tubes misplaced in the trachea. 2
• The X-ray should confirm the tube is not coiled in the esophagus, positioned in the lung or pleural cavity, and that the tip is properly located in the stomach (not the fundus where migration risk is higher). 1

Alternative Bedside Methods (When X-ray Unavailable)

While radiography remains mandatory before feeding, these methods can provide additional information:

pH Testing of Aspirate

• Aspirate gastric contents and measure pH, which should be <5.5 to suggest gastric placement. 1
• Critical limitation: pH testing was not possible in 44% of cases in one study, and when unavailable, subsequent X-ray confirmation caused a 2-hour delay to feeding. 3
• pH testing does not warn of lung placement or potential trauma. 3

Ultrasound Visualization

• Ultrasound on neck and abdomen echo windows with air injection has a sensitivity of 0.96 (95% CI 0.92-0.98) for detecting proper placement. 4
• Ultrasound with saline injection has a sensitivity of 0.98 (95% CI 0.83-1.00). 4
• However, ultrasound does not have sufficient accuracy as a single test to confirm gastric tube placement and should not replace radiography. 4
• Ultrasound may be useful in settings where X-ray is not readily available to detect misplaced tubes. 4

Electromagnetic Tracking

• Electromagnetic (EM) tracing showed 100% agreement with X-ray confirmation in one study of 127 tube placements. 3
• EM tracing warned of lung placement prior to damage in 7% of placements, unlike pH testing or post-placement X-ray. 3

Methods That Are UNRELIABLE and Should NOT Be Used

Auscultation ("Whooshing Test")

• Bedside auscultation is unreliable and dangerous for verifying nasogastric tube position, with only 79% sensitivity and 61% specificity. 1
• Auscultation should never be used as the sole confirmation method because inappropriate tube locations may produce sounds that are misinterpreted as proper gastric position. 2
• Multiple case reports document catastrophic complications when feeding was started based on auscultation alone. 2, 5
• The "whooshing testing" for tube placement verification is not recommended. 5

Clinical Assessment (Adjunctive Only)

While clinical assessment should always be performed, it cannot replace radiographic confirmation:

• Visualize for bilateral chest movement (suggests not in airway). 6
• Listen for equal breath sounds over both lung fields. 6
• Note any resistance during insertion, which may indicate submucosal tunneling or improper placement. 5
• Monitor for emerging clinical signs after insertion such as abnormal drainage fluid, hypotension, or anemia suggesting complications. 5

Ongoing Monitoring After Initial Confirmation

• Recheck tube position radiographically if there is any clinical concern about migration, after patient repositioning, or if the external tube length marking has changed. 2
• Secure the tube properly, as 40-80% of NG tubes become dislodged without proper securement. 1
• Consider nasal bridles for high-risk patients, which reduce accidental removal from 36% to 10% compared to tape alone. 1

Common Pitfalls and How to Avoid Them

• Never start feeding based on auscultation alone - this has led to life-threatening complications including aspiration pneumonia. 2
• Do not assume proper placement even if the patient tolerates insertion well - tubes can enter the lung, pleural cavity, or coil in the esophagus without obvious symptoms. 1
• If dysphagia worsens with the tube in place, suspect pharyngeal coiling and perform endoscopic evaluation or reinsert the tube. 1
• Ensure adequate tube radio-opacity - some PVC Ryles tubes are insufficiently radio-opaque (57-73% adequate) and invisible in 23% of cases, creating risk of error. 3