Intravenous Anaesthetics

Question 1

Drug can be administered through what routes

Answer 1

Oral
Rial.
Transdermal.
Transmucosal.
Intramuscular.
Intravenous

Question 2

List three options of transdermal topical anesthetic agents

Answer 2

Effective topical anesthesia with EMLA cream
LMX (plain lidocaine cream)
2% lidocaine jelly

Question 3

True or false is the maintenance of general anesthesia feasible with total intravenous anesthesia

Answer 3

True

Question 4

List five groups of intravenous, anesthetic agents

Answer 4

Barbiturates
Benzodiazepines
Ketamine.
Etomidate
Propofol 

Question 5

What is the function of the reticular activation system?

Answer 5

The reticular activating system (RAS) is a network of neurons located in the brain stem that project anteriorly to the hypothalamus to mediate behavior, as well as both posteriorly to the thalamus and directly to the cortex for activation of awake, desynchronized cortical EEG patterns

Question 6

What is the mechanism of action of barbiturates?

Answer 6

Barbiturates depress the reticular activating system in the brainstem

The mechanism of action is through binding of a GABA receptor, and potentiates the action of GABA, in increasing the duration of opening of a chloride specific ion channel

Question 7

Why do thiobarbiturates have a greater potency, more rapid onset of action and short duration of action than phenobarbital?

Answer 7

This is because replacing the oxygen with a sulfur atom increases the lipid solubility

Question 8

What effect does protein binding have on tissue uptake of IV anesthetic agent

Answer 8

Protein binding decreases a tissue uptake of IV anesthetic Agents

Question 9

How does decreased plasma concentration of albumin affect IV anesthetic agents?

Answer 9

Decrease plasma concentration of the albumin allows more non-protein bound, IV anesthetic agents to be freely available in the plasma, producing a overdose effect

Question 10

What are the physical characteristics of the drug that determine how rapidly is taken up by tissues?

Answer 10

Lipid solubility.
Molecular size.
State of ionization

Question 11

How does lipids solubility affect the optic of IV anesthetic agents?

Answer 11

Increase lipids, solubility increases the tissue take

Question 12

For water soluble IV and aesthetic agents molecular size affects the tissue uptake

Answer 12

Smaller water, soluble molecules have an increased tissue uptake

Question 13

How does the state of ionization affect the tissue uptake of the IV anesthetic agent?

Answer 13

Non-ionized IV anesthetic agents are more readily diffused across the cell membrane

Question 14

List two lipid soluble, barbiturates

Answer 14

Thiopental
Thiamylal

Question 15

What are the side effects of using concentrations greater than the recommended concentration for barbiturates?

Answer 15

It can cause unacceptable incidents of pain on injection and venous thrombosis

Question 16

How do you minimize any effect of redistribution of a barbiturate that causes rapid regain of consciousness?

Answer 16

This can be eliminated by giving repeat, barbiturate that causes saturation of the redistribution tissues, allowing elimination to be primarily by the liver or kidney 

Question 17

What process is responsible for the awakening from a single sleep dose of any lipid soluble barbiturates

Answer 17

Redistribution

Question 18

Describe the process by which barbiturates are bio transformed

Answer 18

Via hepatic oxidation to inactive water, soluble metabolites

Question 19

Why is methohexitol cleared by the liver more rapidly than thiopental?

Answer 19

This is because of the greater hepatic extraction of methohexital

Question 20

How do the properties of the active barbiturates compound prevent them from being excreted, as is by the kidney

Answer 20

The high protein binding capability of the barbiturates prevent them from glomerular filtration.

The high, lipid solubility of the barbiturates promotes renal tubular reabsorption