How much epinephrine may you give?

The American and NY Heart Associations: For pts at cardiac risk, you may give a maximum of 0.04 mg (40 g) epinephrine.

How much is that? One 1.8 cc cartridge of 1:100,000 epinephrine contains 18 g epinephrine. So 40 g epinephrine is contained in about 2 cartridges.

Question of whether or not to use vasoconstrictor:

Don’t if the pt’s MD forbids it.

If the MD does not permit epinephrine, then you may NOT use levonordefrin either.

It is often said that a pt is likely to suffer more adverse effects from endogenously-released epinephrine due to pain if the LA wears off, than from a vasoconstrictor given to prolong the duration of anesthesia. However, this assessment is difficult to quantify. It has been shown that at resting levels, the epinephrine from 1 carpule can approximately double the amount of systemic epinephrine.

The bottom line: if there is any question as to whether or not to use vasoconstrictor, call the pt’s MD and discuss it. If you can’t use a vasoconstrictor, stay on top of the pain situation by giving more frequent injections.

Category: Pharmacology Notes