Ryles Tube

RYLES NASOGASTRIC TUBES

A nasogastric tube is a narrow-bore tube passed into the stomach via the nose. It is used for short- or medium-term nutritional support, and also for aspiration of stomach contents – eg, for decompression of intestinal obstruction.

A wide-bore tube is used if drainage is needed; otherwise, a finer-bore tube is used. Fine-bore feeding tubes (gauge less than 9) cause less discomfort and less risk of rhinitis, pharyngitis or oesophageal erosion.

The use of a nasogastric tube is suitable for enteral feeding for up to six weeks. Polyurethane or silicone feeding tubes are unaffected by gastric acid and can therefore remain in the stomach for a longer period than PVC tubes, which can only be used for up to two weeks. For long-term enteral feeding, the use of percutaneous endoscopic gastrostomy (PEG) is associated with improved survival, better tolerance by the patient and lower incidence of aspiration.

FEEDING BY NASOGASTRIC TUBES

Bolus: by gravity – very simple, requiring minimal equipment but increases the risk of gastrointestinal symptoms.
Intermittently: by gravity or pump – gives time free of feeding but increases the risk of gastrointestinal symptoms.
Continuously: by pump system – reduces the rate of gastrointestinal symptoms but the patient is connected to the system most of the time and this may limit mobility.
Semi-recumbent positioning of the patient reduces the risk of airway aspiration.
Contamination of feeds can be minimised by minimal, meticulous handling and the use of closed rather than open systems.