Lecture 6 - Parenteral Nutrition Flashcards
PN Indications for use
- pts whose nutritional needs cant be met with enteral feedings w/I 7 days
- Pts w/ severe malnutrition or catabolism where GI tract no useable
- GI tract not functional
PN CI
- pts w/ functional or usable GI tract capable of absorption
- Less than 5 days of treatment
- prognosis doest warrant aggressive nutrition or when not wanted by pt/faily
** If the gut works, use it **
When can PN be life saving?
- functional short gut
- prematurity
- inflammatory lesions
- ileus
- anatomic short gut
- severe anorexia/hypermetabolsim
- cancer
- burns
PN access
Central = catheter tip into SVC/RA junction
PICC = use perisperhal veins insert tip into SVC/RA junction
Peripheral = catheter not in heart, Max PN 900mOsm/l
Peripheral PN info
- limited to max osmolality of 900mOsm/L
2. Ideal pts = adequate veins, short duration, not critically ill, not fluid restricted
Macronutrients of PN
Dextrose
Protein (amino acid)
Fat
Micronutrients of PN
Electrolytes
Minerals
Vitamins
Trace elements
Protein req
healthy adult = 0.8g/kg/day
critical ill = 1.2-2.5g/kg/day
moderate = 1-1.5g/kg/day
severe stress = 1.5-2g/kg/day
restrict protein - hepatic encephalopathy, renal failure when dialysis CI
4kcal/g amino acids
Protein calories
15-20% calories should be protein
health adult = 300 nonprotein calories to utilize 1g N2
critical ill = 100-150NPC 1g N2
Dextrose Info
- cheap, stable,easily stored
- 3.4kcal/g
- fuel sources for CNS,RBC, renal medulla
- 10% ok for PIV
- Osm > 900 req CVL
What happens if give over max dextrose?
fatty liver
insulin resistance
hyperglycemia
dont exceed 4-7mg/kd/min, 5.8-10g/kg/day
IV Fat emulsion info
- 2nd source of NPC
- 9kcal/g
- use hormone + prostaglandin synthesis, cell membrane structure
Electrolyte Req
sodium potassium chloride acetate magnesium calcium gluconate phosphorus
PN with zero chloride is….
rare…question it
Typical Trace elements
Zinc Copper Chronium Manganese Selenium iron
Multivitamin info
** Should always be included in PN, if not IV for available atleast give thiamine***
Admin of TPN
24hr = hospitalized pts
Cyclic = popular w/ home patients, must be tapered on/off
Lipids = separate infusion, 12hr hang time…TNA = 24hrs hang time
Refeeding syndrome
- occurs in malnourished pts receiving aggressive PN
consequences: hypo- kalemia/phosphatemia, cardiac arrythmias, respiratory failure
management: close monitoring of dextrose, K, Mg, Phos
infectious complications of PN risk factors
- critical illness
- foreign body in bloodstream
- mucosal atrophy
- multiple antibiotics
Metabolic complications of PN
Azotemia electrolyte imbalance glucose intolerance cholestasis metabolic bone disease urolithiasis coagulopathy, thrombocytopenia
Mechanical complications of PN
- CVL related…malposition, blockage, embolization
2. infusion related = superficial or deep extravasation
PN associated Cholestasis
amino acid imbalances ratio of carb:fat nutrient deficiencies phytosterols inflammaton lack of enteral feeding
Preventing PNAC
Cycling PN
Trophic Enteral feedings
Protection of PN from light
PNAC treatment options
Limit IV fat < 1g/kg/day average
Limit carb calories
Reduce copper and manganese in PN
Eliminate hepatotoxic meds
Absolute: 100% enteral feedings and no PN *****
Aluminum toxicity
- associated with impaired bone mineralization, renal insufficiency and neurotoxicity
- FDa mandate limit al intake in PN < 5 mCg/kg/day
- neonates greatest risk
- avoid product with aluminum contamination
Max tolerance lvl for fat
2.5g/kg and 60% of energy
Min amount and Max infusion rate carbs/day
min= 100g
max rate = 5mg/kg/min
General compounding guidelines
Phosphorus first, calcium last
Assess visually
Most conc first, least conc last
Factors affecting Ca/Phos solubility
- Ca/Phos salt conc
- pH of final solution
- Type/quantity of AA used
- Temp
- Time
- Mg content
- order of mixing
Calcium-Phosphorus Solubility FDA Safety Alert
3-1 1. Solubility of calcium should be calc from the volume of solution at the time the calcium is added, not final volume
- Some brands of amino acids contain phosphorus and must be considered when calc the final phosphorus conc
- Phosphate added prior to calcium
TNA
3 in 1 solution
simplified Admin
improves pt tolerance
allows lipid infusion over 24hrs = less side effects
dont use pediatrics