Tube types, indications and who gets which
Enteral nutrition is used when the gut works but oral intake is unsafe or inadequate — stroke with dysphagia, head and neck cancer, mechanical ventilation, severe burns with high metabolic demand, or persistent poor intake with weight loss. The guiding rule the exam applies is simple: if the gut works, use it, because enteral feeding maintains mucosal integrity and carries far lower infection risk than parenteral nutrition.
Short-term access, meaning under four to six weeks, uses a nasogastric or nasoenteric tube. A nasoduodenal or nasojejunal tube places the tip past the pylorus and is preferred when aspiration risk or gastric emptying delay is significant. Long-term access uses a gastrostomy or jejunostomy tube placed endoscopically or surgically, commonly called a PEG tube.
Feeding schedules are also tested. Bolus feeds deliver a set volume over minutes and are more physiologic but less tolerated. Intermittent feeds run over thirty to sixty minutes several times daily. Continuous pump feeding delivers a steady hourly rate and is standard for small-bowel feeding and for clients at high aspiration risk, because the duodenum and jejunum cannot accommodate bolus volumes.
| Access | Duration | Notes |
|---|---|---|
| Nasogastric | Under 4–6 weeks | Easy placement; verify by x-ray, then pH and marking |
| Nasoduodenal / nasojejunal | Under 4–6 weeks | Lower aspiration risk; continuous feeding only |
| PEG (gastrostomy) | Long term | Site care daily; rotate the bumper per protocol |
| Jejunostomy | Long term | Continuous feeds; never bolus |
Verifying placement — the most tested step
After initial insertion, radiographic confirmation is the only acceptable verification before the first use. Any answer that begins feeding based on auscultating an air bolus is wrong; the air-insufflation method is unreliable and no longer accepted practice.
Ongoing verification before every feeding, medication and at least every four to eight hours during continuous feeds combines several checks: measure the external tube length and compare it with the documented insertion mark, aspirate gastric contents and test pH, and observe the appearance of the aspirate. Gastric aspirate is typically cloudy, green, tan or off-white with a pH of five point five or less, while respiratory secretions are usually pale yellow and pH above six, and intestinal aspirate is golden or bile-stained with a higher pH. Acid-suppressing medications raise gastric pH, so pH is supportive evidence rather than proof.
If the tube marking has changed, if the client shows respiratory distress, or if placement is genuinely uncertain, stop, hold the feeding and obtain an x-ray. Coughing, choking, or a sudden fall in oxygen saturation during feeding means stop the infusion, turn the client to the side, suction, and notify the provider.
- •New tube: x-ray before first use, every time
- •Before each use: tube marking plus aspirate appearance plus pH
- •pH 5.5 or lower supports gastric placement
- •Never rely on the whoosh of injected air
- •Any respiratory symptom during feeding: stop and assess first
Safe administration, flushing and medications
Position the client with the head of the bed at thirty to forty-five degrees during feeding and keep it up for at least thirty to sixty minutes afterwards; for continuous feeding the head stays elevated continuously unless contraindicated. If the client must lie flat for a procedure, the feeding is paused. This single measure prevents more aspiration than any other nursing action and is the answer to most tube feeding priority items.
Check the formula for expiry, use room-temperature formula because cold formula causes cramping, and limit hang time to four hours for open systems or per manufacturer guidance for closed systems. Change the administration set every twenty-four hours. Monitor gastric residual volume per facility policy; many settings no longer hold feeds for modest residuals, but the exam expects you to reassess the client, return the aspirate unless policy states otherwise, and report high residuals with distension, nausea or vomiting rather than simply discarding the fluid.
Medication administration through a feeding tube has its own rules. Use liquid forms when available, never crush enteric-coated or extended-release tablets, dilute crushed immediate-release tablets in water, give each medication separately, and flush with fifteen to thirty millilitres of water before, between and after doses. Phenytoin and some other medications bind to formula and require holding the feed before and after the dose. Never add medication to the formula bag.
Complications and how to fix them
Diarrhoea is the most common complication and rarely means stopping nutrition. Causes include a rate that is too fast, hyperosmolar formula, cold formula, bacterial contamination, sorbitol-containing liquid medications and antibiotic-associated infection. Interventions include slowing the rate, checking formula handling and hang time, reviewing the medication list, and testing for Clostridioides difficile if antibiotics are involved.
Constipation, dehydration and hyperglycaemia also appear. Free-water flushes are the main hydration intervention, since formula alone rarely meets fluid needs. Blood glucose is monitored, especially in diabetes and critical illness. Tube occlusion is prevented by routine flushing and treated with warm water and gentle pressure — never a stylet, never carbonated cola, never force.
Refeeding syndrome is the high-yield endocrine and electrolyte complication. In severely malnourished clients, reintroducing nutrition drives insulin release that shifts phosphate, potassium and magnesium into cells, producing weakness, arrhythmias, respiratory failure and confusion within the first few days. Prevention means starting feeds slowly, monitoring phosphate, potassium and magnesium daily, and replacing electrolytes before advancing the rate. A falling phosphate on day two of feeding a malnourished client is a report-now finding.
Site care, teaching and exam strategy
PEG site care includes daily assessment for redness, drainage, leakage and skin breakdown, cleaning with soap and water, keeping the area dry, and stabilising the external bumper so it is snug but not tight. Report significant leakage, purulent drainage, granulation tissue causing bleeding, or a tube that has become dislodged. A dislodged mature gastrostomy tract can close within hours, so this is an urgent call, not a routine one.
Home teaching covers hand hygiene, formula storage and expiry, positioning, flushing schedules, recognising aspiration signs, daily weights and when to call. Caregivers perform return demonstration, and written instructions are supplied. Encourage oral care even when nothing is taken by mouth, because oral colonisation contributes to aspiration pneumonia.
On the exam, if the stem mentions coughing, desaturation or a change in tube marking, the answer is stop and assess. If it mentions a malnourished client newly started on feeds with falling electrolytes, it is refeeding syndrome. If it mentions a blocked tube, it is warm water and gentle flush. Recognising the pattern in one line saves time on every item.