Test #2 Illicit Substances / Cocaine ARTICLES - Rude man

Question 1

There was a study that testing driving performance with drugs. Does exposure to cannabis alone affect driving performance?

Answer 1

in that study, no it did not.

but if you add alcohol to it, i definitely will.

Question 2

What is the elimination half-life of cannabis for the occasional user? How about the chronic (no pun intended) user?

Answer 2

occasional user: approx. 56 hours

chronic user: approx. 28 hours

(however, it can be sequestered in adipose tissue, extending its half-life to approx. a week)

Question 3

Complete elimination of a single dose of cannabis may require how much time?

Answer 3

30 days, as THC can remain in the body a long time after being smoked.

the metabolism of cannabinoids creates more than 20 metabolites, most with psychoactive properties.

Question 4

How does marijuana effect the cardiovascular system? (2)

Answer 4

myocardial depression and tachycardia

try to avoid drugs that can increase heart rate - ketamine, pancuronium, atropine, and epi

Question 5

What is the half-life of cocaine?

Answer 5

0.5 - 1.5 hours

Question 6

How is cocaine metabolized?

Answer 6

plasma and liver cholinesterases

the metabolites are water soluble and are excreted in the urine

Question 7

Cocaine is extracted from the leaves of what plant?

Answer 7

Erythroxylon coca

Question 8

What is cocaine’s mechanism of action?

Answer 8

it interferes with the presynaptic uptake of sympathomimetic neurotransmitters (eg. norepi, serotonin, and dopamine)

(a powerful euphoria is produced d/t free catecholamines stimulating the sympathoadrenal axix and prolongation of dopaminergic activity in the limbic system and adrenal cortex.

Question 9

What happens to the blood flow in areas like the brain and heart when taking cocaine?

Answer 9

they are compromised as these vessels vasoconstrict or vasospasm temporarily.

this may lead to irreversible brain damage, stroke, and myocardial infarction or depression.

Question 10

What can high doses of cocaine do to the heart?

Answer 10

depress ventricular function and slow electrical conduction

Question 11

________-resistant hypotension may be encountered with cocaine use. However, it appears that low doses of _____________, titrated to effect, usually restore blood pressure

Answer 11

ephedrine-resistant

phenylephrine

Question 12

Beta-blockers are contraindicated with cocaine use. Why?

Answer 12

because of the potential for unopposed alpha-adrenergic stimulation

Question 13

How long should you recommend that a patient be cocaine-free prior to an elective surgery?

Answer 13

at least 1 week

if you could just hold off on the cocaine for a week or so… then you can resume your previous schedule

Question 14

What medication has the potential to be an effective cocaine-abuse therapy?

Answer 14

ondansetron (0.2mg/kg, subcutaneous)

Question 15

What are some of the effects of hallucinogen drugs, such as LSD, PCP, and mescaline?

Answer 15

they activate the sympathetic nervous system by causing hypertension and tachycardia

increase in body temp and dilation of pupils

Question 16

The effects of hallucinogens can last how long after ingestion?

Answer 16

effects develop over 1-2 hours and last for approx. 12 hours

Question 17

With hallucinogen drugs, extreme caution should be used when administering medications that have a sympathomimetic stimulating effect, like ephedrine.

Answer 17

not a question, just good to know.

Question 18

What two medications are the optimum choice for management of hypertension and tachycardia related to the hyperadrenergic state of cocaine abuse?

Answer 18

titration of esmolol and nitroprusside.

esmolol is selective beta1 and is a better choice than a non-selective beta agonist like propranolol

Question 19

Do local anesthetics, such as tetracaine, procaine, and chloroprocaine, augment or attenuate the proconvulsive effects of cocaine?

Answer 19

they may actually augment the proconvulsive effects.

craziness….

Question 20

Which volatile agent would theoretically be the best choice to use with a cocaine abuser?

Answer 20

isoflurane, since it has less myocardial depressant effects and has a high threshold to induce cardiac arrhythmias.

Question 21

Chronic use of cocaine may cause catecholamine depletion. Would this cause an increased or decreased MAC requirement?

Answer 21

decreased MAC requirement