Anesthetics

Question 1

Used to relive anxiety

Answer 1

Benzos

Question 2

Used for muscle paralysis

Answer 2

Neuromuscular blockers (selective for motor Nicotinic receptors)

Question 3

Depolarizing NM blocking drug

Answer 3

Succinylcholine

Complications: hypercalcemia and hyperkalemia

Question 4

Reversal of succinylcholine

Answer 4

Phase I (prolonged depolarization) - no antidote.  Block can be potentiated by cholinesterase inhibitor 
Phase II (depolarized by blocked) - antidote = AchE inhibitors (Neostigmine)

Question 5

Non-depolarizing NM blocking drugs

Answer 5

-“Curare”-like drugs: compete with Ach for receptors

Question 6

Reversal of “curare” drugs

Answer 6

Cholinesterase inhibitors (Neostigmine, Endrophonium)

Question 7

Prevent secretion of fluids into respiratory tract

Answer 7

Anticholinergic drugs

Question 8

Rapid induction of anesthesia

Answer 8

Short-acting barbs (Thiopental)

- Decreased cerebral blood flow

Question 9

Most common drug used for endoscopy

Answer 9

Midazolem

Question 10

Rx for benzo OD

Answer 10

Flumazenil (GABA antagonist)

Question 11

Inhaled anesthetics

Answer 11

Halothane (most soluble in blood –> slow induction/recovery, Nitrous oxide (least soluble in blood –> fast induction/recovery), Enflurane, Isoflurane, other -fluranes.

Question 12

Halothane toxicity

Answer 12

Liver

Question 13

Methoxyflurane toxicity

Answer 13

Kidneys

Question 14

SE of enflurane

Answer 14

proconvulsant

Question 15

N2O toxicity

Answer 15

Expansion of trapped gas

Question 16

Arylcyclohexylamines

Answer 16

aka: Ketamine (blocks NMDA)

- Dissociative agent; cardiovascular stimulant, increases cerebral blood flow

Question 17

Opiates

Answer 17

Morphine, fentanyl

- Used with other CNS depressants for general anesthesia

Question 18

Propofol

Answer 18

Used for rapid anesthesia induction in short procedures. Less post-op nausea than thiopental. Potentiates GABAa.

Question 19

MAC

Answer 19

Minimum alveolar concentration at which 50%of population is anesthetized.
- MAC is usually expressed in % of gas in a mixture required to achieve effect (the smaller the MAC the more potent the drug)

Question 20

Local anesthetics

Answer 20

Block Na channels on the inner portion (preferentially in activated Na channels) --> work best in rapidly firing neurons 
Order of blockade: 
small > large fibers
myelinated > unmyelinated fibers
autonomic/pain > touch/pressure > motor

Question 21

Esters

Answer 21

Procaine
Cocaine
Tetracaine

Question 22

Amides

Answer 22

Lidocaine
Mepivacaine
Bupivacaine (SE: cardiotoxic)
(Amides have 2 I’s in name)

Question 23

Local anesthetics and infection

Answer 23

Infection = acidic environment –> basic anesthetics are more likely to be ionized –> higher dose may be needed

Question 24

Rx for malignant hyperthermia

Answer 24

Dantrolene: prevents Ca release from SR in skeletal muscle

Question 25

Allergic reactions in local anesthetics

Answer 25

Esters via PABA formation –> switch to amides