Lec 3- Aseptics

Question 1

TPN history

Answer 1

• 1656- Wren infused wine into dogs
• 1960- IV nutrition using dextrose and plasma protein
• 1970- Amino acid solutions and lipid emulsions
• 1980- All in one bag
• 1990- Commercial ready bags
• 2000+ -Genetically/PK tailored bags

Answer 2

• Healthcare professionals should consider parenteral nutrition in people who are at risk of malnutrition and meet either of the following criteria
  
  • Inadequate or unsafe oral and or enteral nutritional intake
  • A non-functional, inaccessible or perforated GI-tract
• Consider PN When it is impossible to maintain nutrition using the gut

Question 3

Who should have TPN

Answer 3

• The patient may need nutritional support for a variety of reasons
  
  • Bowel surgery- GIT will not be working
  • Crohn’s disease- IBD- leakage of blood vessels into the intestine, we are meant to get from the GIT into the blood- poor absorption
  • Burns- Adrenaline (catecholamine) is very high- this greatly enhances catabolism= breakdown muscle or etc
  • Fistulas- abnormal passage within the bowel
• You may also use criteria in deciding to place a person on nutritional support
  
  • BMI <18.5= probable/ 18.5-20 = Possible/ >20= unlikley (apart from burns victims)

Question 4

What is Mas. Brisks TPN requirements

Answer 4

• Mas Brisk
  
  • 2 months
  • 5.4 Kg
  • 58 cm
  • Preoperative assessment for nutritional risk
  • Listed for congenital heart defect restoration
  • Feed is nasogastric but normal
• NB- Do NOT give TPN due to nasogastric feeding even though BMI is 16 (<18)

Question 5

TPN- What

Answer 5

• Nitrogen- Amino Acids
• Calories- Dextrose; Fat emulsions
  
  • We give dextrose instead of starch because we are giving IV so must be digested form of food. Nasogastric tube we give hole foods
• Vitamins- immune system, coagulation, bone
• Trace elements: Na, K, Ca, PO₄, Mg, Zn

Question 6

TPN form

Answer 6

• Renal- give smaller volume due to poor functioning of the kidneys- overloading with fluid can exacerbate damage
• Central line v Peripheral line
  
  • A central line straight in blood vessels close to the heart- larger vessels = amount (volume) of blood and speed is larger
  • 900mOsm/L is the max for central/ 600mOsm for peripheral max (same as the blood)
  • CL requires surgery
• Cl:acetate ratio must be balanced to prevent
  
  • Cl= cause H⁺ ion retention, which induces a metabolic acidosis
  • Acetate= is converted to bicarbonate, which can induce a metabolic alkalosis
    
    • If primary metabolic acidosis or alkalosis is diagnosed, the chloride to acetate ratio can be modified in the PN solution if Doc/Specialist desires

Question 7

TPN- What amounts

Answer 7

• One of the main reasons to give PN is to give energy
• Energy is supplied in a duel mix of carbohydrate and fat
• Remember if it’s given IV it becomes sugar and lipids respectively because they are already digested
• If you give fats (e.g. lard, ghee) or carbohydrates (e.g. starch) you would kill

Question 8

What amounts

Amino Acids

Answer 8

• 0.8/Kg/Day
• Adults with normal metabolism and organ function
• Increased to 1.2-1.5 g/Kg/Day for metabolic needs
• Max 2-2.5 g/Kg/Day in exceptional cases
• Every Amino Acid supplies essential nitrogen
• Typically all amino acids are 1:1 ratio