Local Analgesia and Anesthesia Flashcards
What are the types of local anesthetic agents?
Ester-type local anesthetic agents
Amide-type local anesthetic agents
What are the ester-type local anesthetic agents?
Procaine
Tetracaine
What is the onset of action for procaine?
Rapid
What is the duration of procaine?
Short
What is procaine used for?
Infiltration
Regional blocks
What is the onset of action for tetracaine?
Slow
What is the duration of tetracaine?
Long
What is tetracaine used for?
Topical anesthesia
What increases the potency of a drug?
Increased lipophilic
What are examples of amide-type local anesthetic agents?
Lidocaine
Mepivacaine
Bupivacaine
What is the onset of action for lidocaine?
Rapid
What is the duration of lidocaine?
Intermediate
What is lidocaine used for?
Local blocks
Regional blocks
Antiarrhythmic (IV)
What is the onset of action of mepivacaine?
Rapid
What is the duration of mepivacaine?
Intermediate (> than lidocaine)
What is mepivacaine used for?
Local blocks
Regional blocks
Intrarticular (horses-diagnostic)
What is the onset of action of bupivacaine?
Intermediate
What is the duration of bupivacaine?
Long
What is bupivacaine used for?
Regional blocks
Epidural anesthesia/analgesia
Intraarticular analgesia (small animals)
What are complications and toxicity of local anesthetic agents?
Local anesthetic overdose IV administration Cardiovascular and CNS toxicity CNS excitation, depression, inconsciousness Centrally mediated muscle contraction/seizures Respiratory center depression = apnea Peripheral vasodilation = hypotension Decreased CO Bradycardia Ventricular fibrillation Cardiac arrest Allergic reaction Methemoglobinemia Tissue damage Infection
What is toxicity dependent on?
Potency
What is topical anesthesia?
On theucous membranes
What is used in topical anesthesia?
Tetracaine or lidocaine 2%
Avoid Benzocaine
Total dose <5 mg/kg
What is used for infiltration anesthesia?
Lidocaine, Mepivacaine, or Procaine
Epinephrine
What does epinephrine cause in infiltration anesthesia?
Prolongs block
Ischemia
Cardiac arrhythmias
What is used in regional anesthesia of the head?
Bupivacaine 0.5%; lidocaine 2% (0.1-0.2 ml per site)
Combine with sedation or general anesthesia
What is used for a brachial plexus block?
Bupivacaine 0.5% or Ropivacaine 0.5% +/- dexmedetomidine 0.5 μg/ml
What should a brachial plexus block be avoided in?
Conscious animals