Phys/Pharm - local anaesthetics Flashcards
at what angle are subcutaneous injections placed?
45 degree angle
when are subcutaneous injections used?
for administration of small amounts of medicine that need slow and steady release, eg. insulin
what are the sites for subcutaneous injections
outer arm
lateral aspects of thigh
abdomen (not 2 inch area around naval)
when are intramuscular injections used?
to provide rapid systemic action and for absorbing larger doses - up to 5ml in ventrogluteal site for adults
at what angle are intramuscular injections given?
90 degree on stretched skin
at what rate should the plunger be depressed for IM injections?
1ml-10seconds
what are suitable sites for IM injections?
- deltoid, dorsogluteal (take care of sciatic nerve), ventrogluteal (primary as avoids all major nerves and vessels)
- children - quadriceps (vastus lateralis)
when are IV injections used?
when a medicine is administered rapidly and directly into vein
at what angle are IV injections given?
25 degrees
when are intradermal injections used?
BCG vaccine against TB, allergy testing, flu vaccine
at what angle are intradermal injections given?
15 degrees
via what type of injection can local anaesthetics be administered?
intradermal
how do local anasthetics work?
block voltage gate Na+ channels on excitable cells
what is the MOA of lidocaine?
- blocks voltage-gated sodium channels in neuronal cell membranes
- inhibits ionic influxes and subsequent signal propagation
solutions of lidocaine should not exceed what % in strength?
1%
