Lec 6- CIVAS

Question 1

CIVAS

Central IntraVenous Additive Service

Answer 1

• The central intravenous additive service supplies many medications that require complex aseptic preparation before administration
• MOST COMMON
  
  • Anti-biotics
    
    • Amoxicillin, Teicoplanin
  • Analgesics
    
    • Morphine, fentanyl, bupivacaine
  • Cytotoxic
  • radiodiagnosis

Question 2

Nurses ‘do and don’t’ do bedside compounding of medication

Answer 2

• There are many pharmaceutical parameters that must be considered
  
  • Method and route of administration
    
    • Final volume
  • Dosage and concentration
  • Reconstitution
    
    • Ringers lactate
    • Ringers
    • Normal saline
    • WFI
  • Precipitation of active or complexation
  • Osmolarity, pH, ionic strength
  • ADR’s

Question 3

Infusion fluid types

Answer 3

• Why infuse in any of the three different solutions
  
  • 5% GLUCOSE
  • 0.9% NaCl
  • Compound Sodium Lactate
• Why not just use water for injection (WFI)
  
  • Not osmotically equivalent to blood= pain/phlebitis

Question 4

Question

What is the osmolarity (mOsmol) of a 5% glucose solution

MW Glu = 180.2

Question 5

Make sure you know

Answer 5

• CIVAS
  
  • Some fo the most common drugs that might be seen
• BNF Key chapters
  
  • Sec 9
  • Appendix A6
• Calculations from real life data

Question 6

Why infuse in any of the 3 different solutions

Answer 6

• 5% Glu = 278 mOsmol
• 0.9% NaCl = 308 mOsmol
• Ringers Lactate = 278 mOsmol (BE CAREFUL)

Question 7

Volume

Answer 7

• A pharmacist needs to supply a suitable volume for both the drug and infusion pump (rate)

Question 8

Volume question

Question 9

Ionic strength

Answer 9

• The reaction rate is often influenced by the ionic strength of the diluent
• Za, Zb numerical charges (2+, -1 etc) of reacting species u is ionic strength, K_o is reaction rate constant, B constant for ionic diameter
• Ampicillin at a constant pH has its rate of hydrolysis altered by the concentration of phosphate or citrate used in the buffer
  *

Question 10

pH

Answer 10

• Not in Teicoplanins case but in several cases drug hydrolysis is controlled by pH
• Amphotericin in D5W must be >4.2 to be stable
• Erythromycin can diluted in D5W or in normal salign but is more stable in 0.9% NaCl

Question 11

Pharmaceutics

Formulation development matters

Answer 11

1. Viable/ Non-viable contamination
2. Additive ranges/ compatibility
3. Osmolarity of the solution
4. Rate of infusion
5. Volume of infusion
6. Location of infusion
7. Ionisation
8. pH
9. Your safety (cytotoxic)