Parenteral & Enteral Nutrition Support Flashcards
When should nutriotnal support be considered?
- Cannot tolerate oral feeding
-
Malnourished
- BMI < 18.5 kg/m2
- Unintentional weight loss > 10% in last 3-6 months
- BMI < 20.0 kg/m2 and unintentional weight loss > 5% in last 3-6 months
-
At risk of malnutrition
- Little or no oral intake > 5 days and/or anticipated poor intake for at least another 5 days.
- Poor absorptive capacity, high nutrient losses, increased nutritional requirements
Why is the GI tract preferred to eneteral support?
- Maintain GI endocrine/exocrine secretions
- Maintenance of GI integrity – tight junctions between intestinal epithelial cells require energy obtained directly from local absorption
- Maintain GI microflora
- Cheaper
- Fewer complications
- Safer
What are indications for Enteral Nutrition?
- Dysphagia: Stroke, Neurological disease
- Upper GI Obstruction: Stricture, Malignancy
- Inability To Eat: Coma, ICU, Head & neck surgery
- High Nutritional Requirements: Burns, Sepsis, Malignancy
- Loss Of Appetite: Anorexia, Cancer
What are route for enteral feeding?
- Naso-Gastric (NG) / Naso-Jejunal (NJ)
- Percutaneous Endoscopic Gastrostomy (PEG)
What is the composition of enteral Feeds?
Commercially prepared feeds usually used, ‘standard’ feed has following characteristics:
- Approx 1 kcal/mL
- Isotonic
- Contains fibre
- Lactose free
- Non hydrolysed protein content approx 40 g/L
- Mixture of simple and complex CHOs
- Long chain FAs (some medium chain and omega-3)
- Essential vitamins and trace elements
Approx 50% calories supplied by CHO, 30% as fat. Additional fluids are also required and will vary according to patient requirements
What are Type of Enteral Feeds?
Concentrated
- Critically ill patients requiring volume restriction
- Hyperosmolar, up to 2 kcal/mL
Polymeric
- Non hydrolysed intact protein as nitrogen source
Elemental/Pre-digested
- Short oligopeptides provide nitrogen source
- Less complex CHOs
- Used for e.g malabsorption, short bowel
Disease specific
- Paediatric in-born errors of metabolism – PKU feeds, renal failure feeds
- Renal e.g low phosphate
What are some complicatons of Enteral Feeding?
- Mechanical: Tube blockage, Tube misplacement (Aspiration), Physical damage
- Gastrointestinal: Nausea, Constipation, Diarrhoea, Abdominal distension
- Biochemical: Re-feeding, Electrolyte disturbances, Micronutrient deficiencies, Hyperglycaemia
- Other: Infection
What is Parenteral Nutrition?
- Parenteral is Intravenous
- Reserved for patients in whom enteral intake is inadequate or unsafe, or where GI tract is non-functional or inaccessible
- Although evidence suggests improved outcomes for malnourished patients on short term feeding, due to potential complications PN is rarely indicated for use for just a few days
What are indication for Paraenteral Nutrition?
- Intestinal Failure / Short bowel
- Inflammatory Bowel Disease – Chron’s, Ulcerative cholitis
- GI obstruction – Malignancy, Stricture, Ileus
- Gut ‘rest’ – Pancreatitis, Post-op bowel resection
- Radiation enteritis
- Congenital bowel defects in paediatrics
What are features of Short Term PN feeds?
- PN feed osmolality approx 900-1500 mosmol/Kg
- Plasma osmolality approx 290 mosmol/Kg
- PN ideally infused into large central vein where rapid blood flow quickly dilutes the high osmolality feed
- Infusion into peripheral veins can result in thrombophlebitis
- Reduce glucose content of feed to reduce osmolality
How is PN administered in the long term?
- Peripherally Inserted Central Catheter (PICC)
- Tunelled central line eg Hickman line
What are the types of Infusion schedules for PN feeds?
- Continuous
- Cyclical
What are features of Continuous Infusion feeds?
- Non-interrupted infusion over 24 hr
- Well tolerated
- Increased propensity for PN associated liver disease
- Reduced mobility
- Reduced quality of life
What are the features of Cyclical feeds?
- Intermittent administration usually over 12-18 hr
- Less well tolerated in critically ill patients
- Approx. normal physiology of intermittent feeding
- Improved mobility
- Improved quality of life
Wat factors should be monitored when giving infusions of PN feeds?
- Nutrient content of feed: Daily, reducing to twice weekly when stable
- Volume of feed: Daily, reducing to twice weekly when stable
- Weight: Daily if concerns regarding fluid balance, otherwise weekly reducing to monthly
- Fluid Balance: Daily, then twice weekly when stable
- Temperature/Blood pressure: Daily
- Anthropometric measurements: Monthly
- Evidence of GI dysfunction (vomiting, diarrhoea, constipation, abdominal distension): Daily, reducing to twice weekly
