Nutrition Clinical Flashcards
What is malnutrition?
A deficiency or excess (imbalance) of energy, protein and other nutrients that causes measurable adverse effects on the tissue/ body size etc and clinical outcome
What abnormal nutrient intake deficiencies is malnutrition associated with?
Nutrient intake
Digestion
Absorption
Metabolism
Excess/nutrition loss
What is acute malnutrition?
Develops rapidly in presence of acute stress/ injury
It is short lived and resolves with improvement
What are the consequences of untreated malnutrition?
Impaired immunity, increased risk of infection
Decreased wound healing
Increase complications
Poor response to medical or surgical therapy (3x more likely to have post op complications)
Decreased growth or development of infant/ child
Death
When would a patient have parenteral nutrition?
Inadequate or unsafe oral or enteral intake
A non functional or perforated GIT
How is parenteral nutrition (PN) administered?
IV
What would be the short term (inpatient) reasons of using PN?
Post surgery if pt NBM (gut rest) for less than 7 days
Obstruction in gut
Severe shock or gut infection
Malnourished or unable to eat
What would be the short term (home) reasons of using PN?
Not functioning gut
Not enough gut to function e.g surgery
-some pts can eats small amounts
-may or may not be permanent
What are the oral sources of nutrition and the (parenteral) sources?
Water (water)
Protein (La.a mixture)
Carbohydrate (glucose)
Fat with essential F.A (lipid emulsion with essential F.A)
Vitamins (vitamins)
Minerals (trace elements)
Electrolytes (electrolytes)
Describe the principles of water volume:
Accounts for around 60% of total body weight
Risk of over or under dehydration
What is the calculation for maintenance fluid?
1500ml + (20ml x each kg of body weight over 20kg)
What are the factors affecting dehydration?
Fever
Acute anabolic state
High temp
Low humidity
GI losses
Burns/ wounds
Blood loss
What are the factors affecting fluid overload?
High humidity
Blood transfusion
Drugs
CF
RF
Describe the features of amino acids as to how they relate to being essential for the body:
20 a.as required for protein synthesis and metabolism
8 essential can’t be synthesised
5 conditionally essential- patients needs exceeds the synthesis in clinically stressed conditions
Which commercially available solutions are there for N (amino acids)?
Synthamin
Vamin
Vaminolact (paediatric)
What are the normal mass of nitrogen prescribed in PN bags?
9g, 11g, 14g or 18g
Why shouldn’t amino acids solutions be administered alone to peripheral circulation?
Amino acids solutions are hypertonic to blood
How much nitrogen does an average adult require?
0.2g N/kg/day
How much non protein energy can an average adult be maintained on?
25-35 non protein Kcal/kg/day
Sourced from both lipids and glucose (dual energy) to minimise the risk of giving too much of either
Why shouldn’t glucose be used alone as an energy source?
Risk of hyperglycaemia
Fatty infiltration of liver (as excess glucose goes into F.A)
Excessive CO2 production
Excessive consumption of oxygen
Excessive F.A deficiency
How many Kcal is 1g of anhydrous glucose?
4Kcal
How many Kcal is 1g of oil?
10Kcal
How much lipid (g) should a patient receive a day?
2.5g lipid/ kg/ day
What is the source of lipids in PN bags?
Mixture of soybean oil+ egg phospholipids
What are the essential fatty acids?
Linoleic acid (52%)
Linolenic acid (8%)
What are other non-essential fatty acids?
Oleic acid (22%)
Palmitic acid (13%)
Stearic acid (4%)
Other (11%)
What are the commercially available sources of lipids?
Intralipid 10%- most common, combine with glucose
ClinOleic 20%
What are the advantages of using lipid emulsions?
Large amount of energy in small amounts of fluid (good for fluid restricted)
Allows peripheral admin (isotonic and venoprotective effect)
Contains some fat soluble vitamins (E&K)
Prevents/ reverses essential F.A deficiency
What are the 2 groups of micronutrients?
Trace elements
Vitamins
What are the main factors affecting micronutrient requirements?
Baseline nutritional state on starting PN
Increase loss
Increase requirement - increase metabolism
Organ function
How can baseline nutrition state on starting PN affect micronutrient requirements?
Acute or chronic onset of illness
Dietary history
Duration and severity of inadequate nutritional intake
How can increase loss affect micronutrient requirements?
Small bowel fistulae/ aspirate- rich in zinc
Biliary fluid loss- rich in copper
Burn fluid loss- rich in Zn, Cu, Se
How can organ function affect micronutrient requirements?
Liver failure- Cu and Mn clearance decreases
Renal failure- Al, Cr, Zn and Ni clearance reduced
Name the trace elements:
10 known
Fe, Cu, Zn, F, Mn, I, Co, Se, Molybdenum, Cr
What are the commercially available solutions of trace elements?
Additrace- 10ml vial
Decan
What are the commercially available vitamin preparations?
Vitilipid N adult- fat soluble
Solivito N- water soluble
Name the electrolytes:
Na, K, Ca, Mg, P, Cl, Acetate
What are the main features of PN bags?
A.as
Glucose+ lipids
Trace elements
Vitamins
Electrolytes
What are the 2 available bags for PN?
Standard- contain an average of what is needed and can add to it
Scratch bags
Describe central admin of PN:
Central line is inserted into chest
-jugular or subclavian vein
The line is tunnelled under the skin
Position is confirmed by X-ray
Risk of complications/ infection
Invasive and costly
Describe peripheral admin of PN:
Can easily get damaged
Considered first line if possible
Need good line care and low tonicity feeds
Pts can be successfully maintained for many weeks
Can be complicated by phlebitis- inflammation of vein
What is the peripheral solution osmolality?
800mOsmol/L