Flashcards in Test #2 Illicit Substances / Cocaine ARTICLES - Rude man Deck (21):
There was a study that testing driving performance with drugs. Does exposure to cannabis alone affect driving performance?
in that study, no it did not.
but if you add alcohol to it, i definitely will.
What is the elimination half-life of cannabis for the occasional user? How about the chronic (no pun intended) user?
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)
Complete elimination of a single dose of cannabis may require how much time?
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.
How does marijuana effect the cardiovascular system? (2)
myocardial depression and tachycardia
(try to avoid drugs that can increase heart rate - ketamine, pancuronium, atropine, and epi)
What is the half-life of cocaine?
0.5 - 1.5 hours
How is cocaine metabolized?
plasma and liver cholinesterases
(the metabolites are water soluble and are excreted in the urine)
Cocaine is extracted from the leaves of what plant?
What is cocaine's mechanism of action?
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.
What happens to the blood flow in areas like the brain and heart when taking cocaine?
they are compromised as these vessels vasoconstrict or vasospasm temporarily.
this may lead to irreversible brain damage, stroke, and myocardial infarction or depression.
What can high doses of cocaine do to the heart?
depress ventricular function and slow electrical conduction
________-resistant hypotension may be encountered with cocaine use. However, it appears that low doses of _____________, titrated to effect, usually restore blood pressure
Beta-blockers are contraindicated with cocaine use. Why?
because of the potential for unopposed alpha-adrenergic stimulation
How long should you recommend that a patient be cocaine-free prior to an elective surgery?
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)
What medication has the potential to be an effective cocaine-abuse therapy?
ondansetron (0.2mg/kg, subcutaneous)
What are some of the effects of hallucinogen drugs, such as LSD, PCP, and mescaline?
they activate the sympathetic nervous system by causing hypertension and tachycardia
increase in body temp and dilation of pupils
The effects of hallucinogens can last how long after ingestion?
effects develop over 1-2 hours and last for approx. 12 hours
With hallucinogen drugs, extreme caution should be used when administering medications that have a sympathomimetic stimulating effect, like ephedrine.
not a question, just good to know.
What two medications are the optimum choice for management of hypertension and tachycardia related to the hyperadrenergic state of cocaine abuse?
titration of esmolol and nitroprusside.
(esmolol is selective beta1 and is a better choice than a non-selective beta agonist like propranolol)
Do local anesthetics, such as tetracaine, procaine, and chloroprocaine, augment or attenuate the proconvulsive effects of cocaine?
they may actually augment the proconvulsive effects.
Which volatile agent would theoretically be the best choice to use with a cocaine abuser?
isoflurane, since it has less myocardial depressant effects and has a high threshold to induce cardiac arrhythmias.