Nutrition Flashcards
What is enteral feeding
Patients who cannot eat any or enough food due to illness, difficulty swallowing, decreased appetite or surgery/obstruction.
- Uses the gut
- Liquid food given down the tube
What is gastroparesis?
Stomach cannot empty its contents properly
What drugs cause gastroparesis?
Opioids, anticholinergics, tricyclic antidepressants, calcium channel blockers, progesterone, tobacco, nicotine, alcohol, aluminium hydroxide antacids.
Why is enteral feeding preferred over parenteral feeding?
- Fewer infections
- Fewer complications
- Less expensive
- Less labour intensive for staff
Side effects of enteral feeding
- Nausea and vomiting reduced by glucose control and antiemetics.
Monitor glucose every 4 hours and adjust insulin regimen - Diarrhoea - rule out C.difficile as it is common during hospitilisation
Emulsifier
It orientates themself at surface/interphase allowing both phases to mix.
It acts on the interfactial tension by increasing adhesive forces.
What surfactant is used in TPN?
Non ionic surfactant
- Has a bulky head that is non ionisable.
What is TPN
Total parenteral nutrition is supplying nutrients via IV route.
PPN
Peripheral parenteral nutrition is when patient have another source of nutrient and this is supplemental.
TPN composition
- Largest phase carbohydrates i.e. Dextrose
- Amino acid being highest source of energy 4kcal/g
- Lipid provides essential fatty acids which is released slowly.
Characteristics of TPN
- Oil-in-water
- Narrow pH
- low osmolality
- Sterile
- Nonpyrogenic
- Stable
- Isotonic
3-in-1 TPN
Consists of carbohydrates, amino acids and lipids
- Less administration time for nurses
- Reduced risk of sepsis
- Uses the same central line
- No premixing required
However:
- Precipitation cannot be seen and is due to cationic salts
- Aggregates can cause embolisms
- Short expiration date of 7 days
- Phase separation may occur
2-in-1 TPN
Consists of carbohydrates and amino acids - excluded lipids
Commonly used in neonates
- Longer stability
However:
- Increased risk of sepsis
- Lipid needs to be administered through a different line
How to avoid precipitation?
Excessive concentrations of calcium phosphate can be overcome by gluconates and glycerophosphates.
Organic salts do not dissociate in aqueous solutions.
Peroxidation degradation
- Leads to bronchopulmonary dysplasia and retinopathy
- Is overcome by adding anti-oxidants into lipid emulsions such as vitamin C and E.
