Maverick Modules (5-6) Drugs & Toxicity Basics Flashcards
_____ of Marcaine or Ropivacaine should be utilized in fractionated dosing, aspirating every ____ cc’s.
20 - 30 cc’s
Aspirate every 5 cc’s
What is Marcaine?
Bupivacaine with epinephrine
How do blocks work at the cellular level?
Na⁺ channel blockade and thus blockade of impulse transmission
Potency is associated with ____ _______.
Lipid Solubility
What determines the onset of a local anesthetic?
pKa (ionized constant)
The higher the pKa, the _____ the onset.
slower
Duration of a block is primarily effected by what factor?
Protein binding
The higher the degree of protein binding, the ______ the duration of the block.
longer
Increased patient age will increase local anesthetic ________.
Duration
How are amides eliminated?
Hepatic metabolism
How are esters eliminated?
Plasma cholinesterases
Which anesthetic class has a greater propensity for allergic reactions? Why?
Esters (due to PABA preservative)
Mass does not increase the ______ of the block, but will increase the _______ of the block.
density ; duration
What is the standard recommended epinephrine dose for regional techniques?
What is the Maverick recommended dose?
Standard = 1:200,000 = 5 mcg/mL
Maverick = 1:400,000 = 2.5 mcg/mL
Can epinephrine be used on “fingers, nose, and toes”?
Yes
(Old info suggested not)
What effect does dexamethasone have on regional blocks?
Decadron = ↑ block duration
What dose of dexamethasone is used as an adjunct for regional blocks?
4 - 8 mg
How does clonidine serve as an adjunct for local anesthetics?
Prolongation of block
What is the primary purpose of local anesthetic adjuncts?
Prolongation of block
____ and ____ of absorption are the primary determinants of the occurrence of local anesthetic toxicity.
rate and extent of absorption
Rate the following from Highest absorption (and thus greatest risk of toxicity) to Lowest absorption.
- Femoral
- Sciatic
- Lumbar Plexus
- Intercostals
- Epidural
- Brachial Plexus
- Caudal
- Intercostals (Highest)
- Caudal
- Epidural
- Brachial Plexus
- Sciatic
- Lumbar Plexus
- Femoral (Lowest)
How would the typical symptoms present for CNS toxicity secondary to LA’s?
What is the progression typically?
Excitatory
Disorientation/incoherence → Tonic-clonic seizures → respiratory depression → arrest
Increases in ____ and ___ typically precede the hypotension, arrhythmias, and cardiac arrest associated with local anesthetic toxicity.
↑ HR and BP
Not having 20% lipid infusions readily accessible with the block cart is considered _________.
Negligent
What is the recommended dose of clonidine as an adjunct for regional anesthetics?
1 mcg/kg
In the event of local anesthetic-induced cardiac arrest that is unresponsive to standard therapy, what drug should be given?
IntraLipid 20% bolus and infusion.
What bolus dose of Lipid Rescue is necessary for LAST?
Intralipid 20% 1.5mL/kg over 1 minute
What infusion dose of Intralipid is necessary after the bolus dose has infused?
0.25mL/kg/min 20% Intralipid
What maximum dose of Intralipid is recommended?
8mL/kg