Entral feeding..access techniques and administration

NGT:

Most enteral feed is given into the stomach to allow the use of hypertonic feeds, higher feeding rates, and bolus feeding. 

Fine bore 5–8 French gauge NG tubes are now used unless there is a need for stomach aspiration, or administration of high fibre feeds or drugs via the tube.

PEG should be considered if the patient need the NGT 4-6 weeks.

NJT:

Jejeunal feeding may be indicated:

- problems with gastric reflux 

- delayed gastric emptying

- in unconscious patients who have to be nursed flat. All

Post pyloric placement can be difficult and various techniques are used.

PEG:

If enteral feeding is likely to be needed for periods of more than 4–6 weeks, a gastrostomy tube can be inserted directly into the stomach through the abdominal wall, using relatively simple endoscopic or radiological procedures.

Indications:

-Neurological disorders of swallowing ( CVA,MS,MND,PD)

-Cognitive impairment and depressed consciousness

-Mechanical obstruction to swallowing

-Long term partial intestinal failure requiring supplementary intake

PEJ:

These tubes can be useful if :

-patients are at risk of oesophageal reflux, although that risk is not eliminated.

-for early postoperative feeding.

Percutaneous endoscopic transgastric jejunostomies (PEGJs) can be placed by passing a jejunostomy tube through a gastrostomy and carrying it through the pylorus.

Similarly, existing gastrostomies can be converted to jejunostomies using a jejunal extension.

Direct, percutaneous, endoscopically guided jejunal puncture is now being performed more frequently and can be used in patients who have had a gastrectomy. 

It is technically difficult and specific training in insertion techniques is required. Leakage problems may occur. 

Surgical jejunostomies are usually placed at the time of other surgery, although laparascopic placement has also been described

Mode of feeding:

Enteral tube feeds can be administered by bolus, or by intermittent or continuous infusion. 

Bolus feeding: 

Entails administration of 200–400 ml of feed down a feeding tube over 15–60 minutes at regular intervals. 
The technique may cause bloating and diarrhoea and bolus delivery into the jejunum can cause a ‘‘dumping’’ type syndrome and should therefore be avoided. 
Bolus feeding can be performed using a 50 ml syringe, either with or without the plunger. 
If the latter is removed, the syringe can be hung up to allow gravity feeding. 

Continuous infusion:

May help with diarrhoea or prevent ‘‘dumping’’ in some patients but it also results in higher intragastric pH levels than bolus feeding which can promote bacterial growth.

It is commonly used for very ill patients but it should be changed for intermittent infusion as soon as possible. 

Continuous feed should not be given overnight in patients who are at risk of aspiration. 

Intermittent infusion:

Provides moderate rates of feed provision via either gravity or pump. 
Breaks in feeding of six hours or more are used, depending on patients’ needs (for example, overnight feeding). 
Post pyloric feeding necessitates continuous administration due to the loss of the stomach

reservoir.

Full BSG guideline here