Recommended Sizes of Ryle's (Nasogastric) Tubes for Adults and Children
For optimal patient safety and comfort, Ryle's tube size should be selected based on patient age, with 8F for infants, 10F for children, 14F-16F for adults, and 18F for adult feeding or lavage purposes. 1
Adult Nasogastric Tube Sizing
- Standard adult sizes: 14F-18F
- 14F-16F: Routine adult use for drainage and medication administration
- 18F: Adult feeding or gastric lavage when larger diameter is needed
Pediatric Nasogastric Tube Sizing
- Infants: 8F
- Children: 10F
- Adolescents: 12F-14F (transitioning to adult sizes)
The American Academy of Pediatrics specifically lists the following nasogastric tube sizes as essential equipment for pediatric care 1:
- Infant: 8F
- Child: 10F
- Adult: 14F-18F
Measuring Insertion Length
The appropriate insertion length is just as critical as selecting the correct tube size. Evidence shows that the traditional nose-earlobe-xiphoid (NEX) method often results in tubes that are too short 2, 3.
Recommended measurement methods:
For adults: Distance from xiphisternum to earlobe to nose + 10 cm provides the most accurate estimate of proper insertion length 2
For children: Follow age-appropriate measurements:
- Use a length-based resuscitation tape for accurate measurement in children up to 35 kg 1
- Document the external tube length after insertion to ensure consistent positioning
Verification of Placement
After insertion, proper verification is essential to prevent complications:
- Required verification: Radiographic confirmation (chest X-ray) is the gold standard
- Interim verification: pH testing of aspirate (<5.5 suggests gastric placement)
- Avoid: Relying solely on auscultation or observing bubbling when the tube is placed in water
Important Safety Considerations
Contraindications:
- Severe facial trauma
- Basilar skull fractures (risk of intracranial insertion) 4
- Coagulopathy (relative contraindication)
Potential complications:
Special situations:
- For patients requiring long-term enteral feeding, consider smaller-diameter tubes (12F-14F) for patient comfort
- For gastric decompression after surgery, larger tubes (16F-18F) may be more effective
Documentation Requirements
- Document tube size, insertion depth, method of confirmation, and patient tolerance
- For pediatric patients, document both weight and tube size to facilitate quality assurance 6
By following these evidence-based guidelines for Ryle's tube sizing and insertion, clinicians can minimize complications while ensuring effective tube function for feeding, medication administration, or gastric decompression.