Nasogastric (NG) Tubes

Question 1

Indications for an NG tube

Answer 1

Gastric lavage 
Drainage and/or aspirate of gastric contents 
Nutritional support
Administration of medication 
Investigations / procedures

Question 2

What investigations or procedures may require an NG tube?

Answer 2

pH testing

Insertion of RIG (radiologically inserted gastroscopy)

Question 3

Examples of why a patient would need an NG tube for administration of meds / nutritional support?

Answer 3

Dysphagia 
Oesophageal stricture 
Poor appetite
Unable to take oral nutrition e.g. recent oral surgery 
Nil by mouth 
Intubated 
- spinal injury patients
- facial trauma

Question 4

Types of NG tubes

Answer 4

Fine bore tubes (guide wire)

Wide bore tubes (Ryles tubes)

Question 5

What are fine bore tubes used for?

Answer 5

Feeding

Medications

Question 6

What are wide bore tubes used for?

Answer 6

Drainage of fluids from stomach
Feeding
Medications
Lavage

Question 7

Routes for NG tubes

Answer 7

Nasal
Oral
Nasojejunal
Percutaneous endoscopic gastrotomy (PEG)/jejunostory (PEJ)

Question 8

Causes for using nasojejunal NG tube

Answer 8

Acute pancreatitis with gastroparesis
Patients with a ventilator with gastroparesis
Post surgical patients with an upper GI enterocutaneous fistula in which a tube can be manoeuvred distal to the origin of the fistula
Hyperemesis gravidarum (very rarely required)

Question 9

Contraindications to the fine bore needle

Answer 9

Oesophageal obstruction 
Acute abdomen 
Small bowel obstruction 
Relative
- Absence of gag reflex 
- Maxillo-facial injury 
- Head and neck cancer
- Agitated / uncontrolled behaviour
- Oesophageal varices 
- post op ileus

Question 10

Complications of NG tube insertion

Answer 10

Poor x ray interpretation
Misplaced tubes - pulmonary placement
Distal tip migrates upward into the oesophagus
Distal tip migrates downward into the duodenum
Coiled in pharynx
Aspiration
Pneumothorax
Sepsis
Pressure Ulcer (nares, cheek, internally)
Refeeding syndrome

Question 11

Monitoring after insertion of NG tube

Answer 11

Biochemical 
- U and Es
- PO4
- Mg
- LFTs
- WCC
- vitamin and mineral status 
Nutritional 
- fluid balance
- food record
- weight 
Anthropometric 
- mid upper arm circumference, triceps fold, mid arm muscle circumference 
Clinical 
- temp 
- pulse
- resp rate
- stool charts
- medication 
- clinical condition 
- nasal passages

Question 12

What electrolyte imbalance would indicate that a patient is at risk of refeeding syndrome?

Answer 12

Hypophosphataemia