IV Drug Administration Flashcards
Reasons for IV drug administration
- medicine is not available in another form
- medicine is not tolerated through another route
- a constant/high blood level of medicine is needed
- rapid onset of effect is needed
- some medicines more effective if done by IV
- to ensure compliance (rarely)
What are the disadvantages of IV drug administration?
- increased cost and time to administer medicine
- requires trained staff
- rapid onset of action, might be to severe for patients
- volume of fluid to dilate the medicine can damage CVS
- can cause pain/discomfort
- health risks eg infections
What is a bolus injection?
a rapid injection of drug directly into the vein over a short period of time (minutes)
What is continuous infusion?
a steady flow of drug over a longer period of time
What is intermittent infusion?
Sequences of doses spaced out over a period of time
When would you use a bolus injection?
- if you need a rapid response
- if there are incompatibilities
- for unstable drugs
When would you use continuous infusion?
- for stable drugs
- drugs with a short half-life
- drugs with time dependent effects
When would you use intermittent infusion?
- for unstable drugs
- drugs with a long half-life
- drugs with concentration dependent effects
- incompatibilities
What are some complications of IV drug administration?
- fear/phobia/pain
- infection/sepsis
- thrombophebitis
- extravasation/infiltration (tip of catheter pierces tissue and drug enters tissue space instead of vein)
- emboli
- anaphylaxis/hypersensitivity
- overdose
What is Red Man Syndrome?
- hypersensitivity reaction due to histamine release
- can be caused by vancomycin
How can Red Man Syndrome present?
- erythematous rash of the face, neck and upper torso
- diffuse burning, itching, generalised discomfort
- rare cases: hypotension, angiodema, chest pain, dyspnea
How can the incidence of Red Man Syndrome be reduced?
- slowing infusion rate of drug
- dilute drug solution more
What are some things that can go wrong with the drugs in IV drug administration?
- insufficient mixing
- stability of medicines in solution (light/temperature/concentration/pH - can cause degradation?)
- interaction of medicine with syringe/bag
What is bioavailability?
the fraction of unchanged drug that reaches systemic circulation. 100% for IV injection
What is clearance?
the volume of blood/plasma cleared of drug per unit time, constant value
