L 19 Flashcards Preview

Pharmacology Fall 2015 > L 19 > Flashcards

Flashcards in L 19 Deck (15):
1

How to administer non-depolarizing NM blockers

All are highly ionized and will not be absorbed
Must be injected

2

NM Blockers and the CNS

Being highly ionized, do not cross BBB
Paralyzed but awake

3

How to reverse a NM block

Administer AchE Inhibitors like Neostigmine to increase Ach in cleft

4

Double burst results for non-depolarizing vs depolarizing drugs

Non-depolarizing: Posttetanic potentiation, and a fade

Depolarizing: no fade, no Posttetanic potentiation

5

Succinylcholine

Depolarizing NMJ Blocker
Made of two Ach molecules
Has same effect as Ach, except lasts longer and leads to desensitization=> paralysis
Effects cannot be overcome with AchE Inhibitors because it is non-competitve.
Allows lots of Na into cell, and K out of cell–problematic for hypersensitive people

6

Contraindications for succinylcholine

Children

7

What can increase NMJ blockade?

Inhaled anesthetics (Isoflurane)
Antibiotics
Tetracyclines
Ca channel blockers

8

How will myasthenia gravis patients respond to succinylcholine?

Greater response due to less N receptors

9

How do burn victims respond to non-depolarizing NMJ blockers?

They are more resistant because they have more N receptors. But, succinylcholine is not good for them for the same reason. =>K+ loss from the cell and potentially heart failure.

10

d-Tubocurarine

Non-Depolarizing NMJ blocker
Releases lots of histamine which can cause hypotension and bronchospasm

11

Atracurium

Non-depolarizing NMJ blocker
Releases histamine liked-Tubocurarine

12

Cisatracurium

Non-depolarizing NMJ blocker
Unlikely to release histamine

13

Hexamethonium

Ganglion blocker
Non-depolarizing competitive antagonist

14

Mecamylamine

Ganglion blocker
Enters brain–causes tremor, sedation, altered mentation

15

Effects of ganglion blockers

Block all ANS ganglia, effects depend on dominant tone in tissue
Eye: cycloplegia, mydriasis
BV: orthostatic hypotension (lost symp stimulation)
Heart: tachycardia
GU: urinary retention, no ejaculation/erection
No sweating
ANS drugs will have same or enhanced effect because target organs not blocked, but feedback mechanisms will decrease