Malnourished or at risk of malnutrition; inadequate or unsafe oral intake; functional and accessible gastrointestinal tract.

Mid-face trauma and recent nasal surgery.

Any two of gagging/vomiting; tissue trauma including nasal haemorrhage and oesophageal perforation; respiratory tree intubation leading to aspiration.

Bridge of nose to earlobe to xiphisternum – usually approximately 55-65cm in an adult.

On reaching the measured distance; if the tube emerges in the oral cavity; if the patient experiences respiratory distress or inability to speak; nasal haemorrhage; significant resistance.

Clinically, with pH testing of apirated fluid from the nasogastric tube – stomach contents have a pH of 0-5. If this is not possible or if the patient takes PPI medication or has had gastric surgery, chest radiograph is required.

Consent to procedure, size and length of tube inserted, any complications during insertion, volume and pH testing of fluid if successfully aspirated, need for chest radiograph if not.

Bifurcation of the carina in the midline, travel past the diaphragm with subsequent deviation to the left, and a visible tube tip (radiographically) or suitable distance at the nasal tip (clinically) to suggest tube is in the stomach.

NICE guidelines recommend using enteral tube feeding for no more than 4 weeks.