Local Blocks

Nerve blocks. I’m a fan. Lido works great. But the other options are very helpful for local blocks after surgery. Here are some basic calculations.

The two blocks I use the most are lido and bupivacaine. These are AmIdes. The things I don’t use (cocaine, procaine, tetracaine) are esters.

Lidocaine 1%, lasts 1 h

I weight about 75 kg. So, the most lidocaine (1%) I should use is:

75kg * 5mg/kg  * 1 mL / 10 mg = 37 mL , without epi

The calculation is mass in kg * 5 / 10 or mass/2

with epi, I can use  75 * 7 / 10= 52 mL, with epi

Bupivicaine (aka Marcaine) 0.5%, lasts for HOURS!!

75 kg * 2.5 mg/kg * 1/5 = 75kg / 2 = 37 mL

Amazing!! this rule is similar to epinephrine. Mass in kg / 2

Bupivicaine/Marcaine + epi

75kg * 3/5 = 45 mL

I think dealing with the large epi dose is going to unnecessarily complicate things and be a source of confusion. Just use the lower dose, kilograms / 2.

Quarter marcaine == use the pts weight in kilos