Module 5.3 (Artificial Nutrition) Flashcards
1
Q
How do we get malnutrition?
A
- inadequate intake to meet nutritional requirements for 7 days OR
- weight loss >10% within 6 months–> require nutrition support
- if the gut works–> entral nutrition (the delivery of nutrients beyond the oesophagus via feeding tubes)
- if gut doesn’t work–> parenteral nutrition (infusing a specialized form of food through a vein (intravenously)
2
Q
What do we want to achieve with nutritional support?
A
- Improve weakness, increase energy
- Improve wound healing
- Ensure drugs are metabolised sufficiently
- Preserve synthetic function of liver i.e. clotting factors
- Prevent infections
3
Q
Who needs nutrition support?
A
- impaired intake e.g. mucositis
- impaired transport e.g. post-operative ileus
- Impaired digestion e.g. pancreatitis
- Impaired absorption e.g. connective tissue disease, GVH
- malnourished – incidence among hospitalised pts up to 55%
4
Q
How do we give nutrional support?
A
- If eating: oral supplements to improve nutrition
- may not be nutritionally complete e.g. Resource
- If oral intake inadequate: EN by tube – feeds are nutritionally complete
5
Q
What are the types of tube feeding?
A
- Via nose (short term)
- Nasogastric (NG)
- Nasoduodenal (ND)
- Nasojejunal (NJ)
- Via ostomy (longer term)
- Gastrostomy (PEG)
- Jejunostomy (PEJ)
- Bolus feeds
- Continuous feeds
6
Q
What patients require EN via tube?
A
- En- enteral (feeding tube)
- Impaired conscious level - comatose
- Impaired swallow e.g. post stroke
- Upper GI disease- gastrectomy
- Oesophageal surgery
- Trauma
- Anorexia nervosa
7
Q
What types of enteral tube feeds for specific conditions?
- renal failure
- diabetics
- pulmonary disease
- critically ill
A
- renal failure
- low protein
- reduced electrolytes
- diabetics
- higher fat content
- more complex carbohydrates
- soluble fibre
- pulmonary disease
- high fat content
- fat oxidation–> less C02 than carbohydrate oxidation
- critically ill
- more branched chain amino acids
- more nitrogen (reduces skeletal muscle breakdown and CO2 production)
8
Q
What is the role of the pharmacist in enteral feeding?
A
- Review need for medication administration via feeding tubes
- Review appropriateness of formulations e.g. conversion of drugs e.g. SR to IR, or oral to IV, or oral to topical
- Dose equivalence, interactions, handling precautions e.g. cytotoxic medications
- Site of absorption of the drug as most drugs absorbed in small intestine
- Some medications may require action of acid to aid dissolution
- Use of references
- Monitor for increase/decrease in effect
- Annotate medication chart
9
Q
What are the general principles for administering drugs via feeding tubes?
A
- flush before and after with 15mL sterile water
- crush tablets or open capsules and dissolv with sterile water
- ensure feeds have been withheld if appropriate
- phenytoin and ciproflocacin- stop feeds 2 hrs before and 1 hr after giving medication
- use liquid forms where possible
- many suspensions/ mixtures contain sorbitol- watch for diarrhoea
- do not add medications to enteral feed formula
- administer each medication separetly and flush between
10
Q
What is refeeding syndrome?
A
- when food is introduced too quickly after a period of malnourishment
- shifts in electrolyte levels that can cause serious complications such as seizures, heart failure, and even coma- be careful how to re initiate re feeding
- Prolonged period of inadequate nutrition which causes:
- down-regulation of cellular pumps (Na+/K+ pump)
- electrolytes leak across cell membranes
- K+, Mg2+ & PO4 move into plasma
- Excreted by the kidneys à total body deficits
- Introduction of Nutrition - Pumps reactivated (catabolic to anabolic) which can cause a potentially lethal shift in fluid and electrolytes
- Carbohydrate-induced release of insulin - moves glucose into cells
- K+, Mg2+ and PO4 move into cells
- Na+ and H2O move into circulation
11
Q
What can refeeding syndrome result in?
A
- acute hypokalaemia, hypomagnesaemia & hypophosphataemia
- Rapid circulatory overload from Na+ & H2O
- Malnutrition also limits renal capacity to excrete salt & water load
- RESULTS IN:
- Acute cardiac failure, cardiac arrhythmias and sudden death
- Neurologic complications – convulsions or coma
- Micronutrient depletion (eg Vit B1 - Wernicke’s encephalopathy)
12
Q
When is TPN used?
A
- Total parenteral nutrition
- Oral or enteral feeding is unsafe or enteral tube feeding cannot be achieved/maintained
- Intestinal failure (where pt is malnourished or where feeding will not resume within 7/7) e.g. post-operative ileus
- Anastomotic leaks or fistulation
- Extensive gut resection
- Swallowing difficulties e.g. Mucositis from chemotherapy/radiotherapy
13
Q
What is TPN made up off?
A
- Base solution
- Amino acids – source of N for protein synthesis
- Glucose – source of energy
- Lipid – source of energy & essential fatty acids
- Additives
- Electrolytes
- Micronutrients
14
Q
What additives do we need?
A
- multivitamins
- water soluble (B group, folic acid, vit c)
- fat soluble
- trace elements (Zn, CU, Mn, Cr)
- electrolytes
- Na+, K+, Ca2+, Mg2+, PO4
- chloride or acetate salts
15
Q
Medications considerations while on TPN
A
- IV PPI – esomeprazole or pantoprazole stress ulcer prophylaxis
- Oral hypoglycaemic agents
- Insulin infusion if needed (aim BSL <7)
- Drugs affecting electrolytes
- -K+ sparing diuretics, loop diuretics
- -IV Abs that contain Na+
- drugs affecting GI function
- Anticholinergics, opioids–> ileus
- Antibiotics or antacids (Mg)–> diarrhoea
