Exam 4- Parenterals III Flashcards
What is a pyrogen?
A fever-reducing substance
What is a disinfectant?
A substance used on in-animate objects to render them non-infectious (cidal vs. static)
What is sterilization?
complete destruction of all viable organisms
What is sterility?
Absence of life
What are some methods of sterilization?
- steam
- dry heat
- filtration
- gas
- ionizing radiation
What is steam sterilization?
- moist heat in the form of saturated steam under pressure (autoclaving)
- the most reliable method for the destruction of all forms of microorganisms
- Kills by the result of coagulation of some protein in the cell (bacteria easier than spores)
- good for bulk solutions, glassware, surgical dressings and instruments, solutions in sealed container (ampoules), sealed empty vials only with a little bit of water
What preparations are steam sterilization not suitable for?
Oils/fats
oleaginous preparations
powders
What is dry heat sterilization?
- microorganism death by oxidation process
- good for dry glassware, petroleum jelly, mineral oils, talcum powder, and some dry powders
What is sterilization by filtration?
- for solutions that cannot be heated at high temperatures
- filtration through a membrane filter
- filters work by interlacing bacteria or particles entrapped in the pores
- complete removal of live and dead microorganisms along with other particulate microorganisms
- inexpensive equipment
Which type of sterilization is good for small volumes?
sterilization by filtration
What are the two factors of sterilization by filtration?
- Primary factor: pore size
- Secondary factor: electrical charge, pH, temperature, pressure
What is gas sterilization?
Destruction of all living microorganisms with a chemical in a gaseous or vapor state
ex) ethylene oxide, propylene oxide
What are advantages and disadvantages of gas sterilization?
- Advantage: not having to expose to high pressure or temperature
- Disadvantage: gas can alter the solubility of the drug which would reduce the compliance
What is sterilization by ionizing radiation?
- UV light
- Gamma radiation
What are some disadvantages of ionizing radiation?
Disadvantages:
- Need a specialized room to do this (gamma)
- rays can go into the substance and contaminate it
Spore to use for autoclave sterility validation
bacillus stearothermophilus
Spore to use for dry heat and gas sterility validation
bacillus subtilis
Spore to use for ionizing radiation
bacillus pumilus
What are pyrogens?
fever-producing organic substances arising from microbial contamination and responsible for many of the febrile reactions in patients following injection
What are some characteristics of pyrogens?
- Endotoxins: gram-negative bacteria
- Lipopolysaccharide
- Thermostable
- Water soluble
Where do pyrogens come from?
- Water used as the solvent
- The Container
- Chemicals
How can pyrogens be removed?
- heating at excessively high temperature
- using a potassium permanganate/barium hydroxide filter
What is the USP Rabbit test?
To test for pyrogens
- use healthy rabbits
- inject the product in their marginal ear vein
- temperature check
What is the Limulus Amebocyte Lysate (LAL) test?
To test for pyrogens
- extract from the blood cells of Horse-crab contains an enzyme and protein that coagulates in the presence of lipopolysaccharides (pyrogen)
- substitution for USP rabbit test
- for the end product testing of human injectible drugs
What is an advantage of the Limulus Amebocyte Lysate test?
- can detect the pyrogens at a very low concentration
- very sensitive
Small volume parenterals
- packaged in small volumes (less than 100 mL)
- available in ready-to-use systems
- extended stability
- reduced wastage
- some products require thawing
Large volume parenterals
- packaged in large volumes
- administered by IV infusion
- no bacteriostatic agent
What are the uses of large volume parenterals?
- maintenance therapy
Total parenteral nutrition (TPN)
-Replacement therapy
Water requirement
Electrolyte requirement
Caloric requirement
Parenteral nutrition
Enteral nutrition
