Nasogastric intubation

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Nasogastric intubation is a medical process involving the insertion of a plastic tube (nasogastric tube, NG tube) through the nose, past the throat, and down into the stomach.

Contents 1 Technique 2 Uses 3 Contraindications 4 Complications 5 References

[edit] Technique

Before you insert a NG tube you must measure with the tube from the tip of the patients nose, to their ear and down to the xyphoid process. Then mark the tube at this level to insure that you have inserted the tube far enough into the patients stomach. The end of a plastic tube is lubricated and inserted into one of the patient's nostrils. It is then moved through the nasal cavity and down into the throat. Once the tube is past the pharynx, it is rapidly inserted down into the stomach.

During the tube's insertion, the patient may gag; in this situation the patient is given water to drink, and the tube continues to be inserted as the patient swallows. Great care must be taken to ensure that it has not passed through the windpipe and down into the lungs. To ensure proper placement it is recommended (though not unequivocally confirmed) that injection of air into the tube be performed,^[1] if the air is detected in the stomach with a stethoscope, then the tube is in the correct position. Another method is to aspirate fluid from the tube with a syringe. This fluid is then tested with pH paper (note not litmus paper) to determine the acidity of the fluid. If the pH is 5.5 or below then the tube is in the correct position. If this is not possible then correct verification of tube position is obtained with an X-ray of the chest/abdomen.^[2] If the tube is to remain in place then a tube position check is recommended before each feed and at least once per day.

[edit] Uses

The main use of a nasogastric tube is for feeding and for administrating drugs and other oral agents (such as activated charcoal and radiographic contrast material). For drugs and for minimal quantities of liquid, a syringe is used for injection into the tube. For continuous feeding, a gravity based system is employed, with the solution placed higher than the patient's stomach. If accrued supervision is required for the feeding, the tube is often connected to an electronic pump which can control and measure the patient's intake and signal any interruption in the feeding.

Nasogastric aspiration (suction) is the process of draining the stomachs contents via the tube. Nasogastric aspiration is mainly used to remove gastric secretions and swallowed air in patients with gastrointestinal obstructions. Nasogastric aspiration can also be used in poisoning situations when a potentially toxic liquid has been ingested, for preparation before surgery under anesthesia, and to extract samples of gastric liquid for analysis.

If the tube is to be used for continuous drainage, it is usually appended to a collector bag placed below the level of the patients stomach; gravity empties the stomach's contents. It can also be appended to a suction system, however this method is often restricted to emergency situations, as the constant suction can easily damage the stomach's lining.

Treatment for severe anorexia can include nasogastric feeding to stabilise bodyweight.

In Britain, nasogastric tubes were used for the force feeding of prisoners who were on hunger strikes as a result of the Cat and Mouse Act.

[edit] Contraindications

Nasogastric intubation is contraindicated (inadvisable) in patients with facial trauma, esophageal abnormalities, and altered mental status or an impaired airway.

[edit] Complications

Minor complications include nose bleeds, sinusitis, and a sore throat. Sometimes more significant complications occur including erosion of the nose where the tube is anchored, esophageal perforation, pulmonary aspiration, a collapsed lung, or intracranial placement of the tube.

[edit] References