So going into a little bit more detail now about alcohol. So the way alcohol works
is it actually activates GABA and serotonin receptors in the central nervous system
and it inhibits glutamate receptors. So this is a problems because GABA receptors are inhibitory
and therefore alcohol can have a very sedating effect on individuals making it dangerous.
The way alcohol is metabolized is through the enzyme, alcohol dehydrogenase
which converts alcohol to acetyl aldehyde and then that is further broken down
by aldehyde dehydrogenase into acetate or acetic acid. Very important to note
people of Asian decent actually have less aldehyde dehydrogenase and therefore
they can tend to become intoxicated very quickly because they're not able
to properly metabolize alcohol, so they can result in having very serious side effects
from alcohol including facial flushing and becoming very extremely nauseous
after even a small amount of use. When you’re screening a patient for an alcohol use disorder,
there're several different screening tools you can use. A few to be familiar with
include the MAST or the Michigan Alcohol Screening Test, the ADI Screening Inventory,
the AUDIT test and also the CAGE questionnaire.
The CAGE is a very easy screening test to administer. So let’s go through it in more detail.
When you’re administering the CAGE, you’re gonna start by asking that individual,
have they ever felt the need to cut down on their alcohol use?
Have they ever been angry or annoyed when people are critical of their drinking?
Ask the individual, “Have you ever felt guilty about your drinking?” and finally inquire
as to whether or not they’ve ever needed an eye opener which is a drink first thing in the morning.
This can be a tell-tale sign that there's an alcohol problem.
What factors do the absorption and elimination rates of alcohol depend on?
Well, age for one, sex or gender, weight and also speed of consumption.
All of these things are going to influence how quickly an individual can metabolize
and process the alcohol consumed. Other things include presence of food in the stomach,
state of their nutrition, chronic alcoholism and also whether or not there is any cirrhosis of the liver.
So if somebody is drinking on an empty stomach, they already have a poor nutritional status,
they tend to drink every day and it’s gotten to the point where their liver is negatively impacted.
They’re not actually going to able to metabolize alcohol very quickly and they’re going to therefore
have trouble with the elimination of it from their system.
When we think of blood levels of alcohol, this can really impact our physiological states.
So when someone’s had a little bit to drink and they have maybe a 0.05% of alcohol in their system,
they’re going to have a little bit of thought and judgment impairment,
but when somebody is increasing their use, they’re gonna start becoming clumsy
and start reaching a legal limit of intoxication. When they go beyond that
and have a level of 0.2%, they can get depression of motor function,
meaning that their gait is gonna be wobbly, they’re not gonna be able to walk in a straight line,
they’re not gonna be able to kind of handle things with fine motor and so forth
as they normally would and then as things increase, they’re gonna become confused
and stuporous and eventually very high amounts of alcohol in the system
can lead to coma and even death.
This is very important. In the United States, the legal limit for intoxication is 80-100 mg/dl
and the differential diagnosis when you’re encountering someone who may seem intoxicated
is think about whether or not their potentially hypoglycemic, whether they might be hypoxic,
if they have a mixed alcohol or drug overdose situation going on,
whether they’ve been poisoned. You’re gonna wonder about hepatic encephalopathy
and also whether or not they might have psychosis and finally any psychomotor seizures.
These are all things that are gonna be in your differential that you wanna rule out
when encountering the patient who seemingly is intoxicated and when you go to
evaluate this individual, you’re going to check blood alcohol level
and also you’re probably gonna do a CT scan of their head. As we’ve mentioned before
when people become intoxicated, they can become stuporous, clumsy and so forth.
And so these individuals are at a very high risk for falling and actually incurring a head injury
that can lead to something serious like a subdural hematoma and so you wanna make sure
to rule that out when you’re evaluating an individual. So how would you treat acute intoxication?
Well, when you’re meeting this individual probably in the emergency room,
you wanna ensure the ABCs, of their airway, breathing and circulation
and make sure that all of that is secure. You’ll check their vital signs and also their blood glucose
and you’re gonna very quickly administer thiamine and also naloxone which the latter,
naloxone, is helped to protect this patient in case they have a mixed drug, alcohol overdose.
The naloxone will help protect in case there’s been any ingestion of opiates.
Alcohol dependency, you’re gonna treat that by referring the patient to something supportive
like an Alcoholics Anonymous meeting or Smart Recovery which is similar to AA
but newer version of group therapy that helps people follow sobriety program
through the supportive peers. You might also think about doing aversion therapy
by giving them disulfiram or antabuse and this again is a medication that actually
will be taken on a day-to-day basis and if a patient consumes alcohol
while taking disulfiram they have a terrible reaction, they get that facial flushing and nausea
and it’s meant to prevent them from ingesting any alcohol.
You can also offer them a medication called naltrexone and this is a medication
that works to reduce the pleasure level of drinking. So how it works is it is an opioid antagonist
and it’s believed that when people drink while taking naltrexone, they don’t enjoy it.
They don’t have the pleasurable response that’s normally associated with drinking
and therefore it makes drinking less desirable.
Psychotherapy is another effective option whether it's one-to-one or in a group setting.
AA has the highest likelihood of success. So just to note, for people
with a chronic alcohol dependency, you really do wanna consider referring them
to some stepwise supportive therapy program.
A little bit more about disulfiram, we mentioned how it can cause a facial flushing and nausea
and this is because it actually inhibits that enzyme, aldehyde dehydrogenase,
which is so important in the metabolism of alcohol. So this is aversive therapy
because it will give people an unpleasant effect if they do drink while taking it.
Some potential side effects if they do drink would be facial flushing, headache, tachycardia and vomiting
along with their nausea and then a little bit more detail about naltrexone,
as I mentioned, it blocks opioid receptors. In particular, the new opioid receptors
and this prevents exogenous opioids from binding there
and thereby prevents the pleasurable effect of opioid or alcohol consumption.
It’s available not only as a pill but it can also be administered in a monthly injection
which is a very nice options for some patients. The side effects include nausea, vomiting
and decreased appetite. For patients who opt for the injectable form of naltrexone,
that can sometimes cause a local reaction at the injection site and some pain.
When it comes to alcohol withdrawal, CNS excitation following the termination
of the depressed effects of long-term alcohol consumption. So this is an important note,
because what is happening is that in withdrawal, the brain is so used to having
those GABA receptors activated from alcohol and these are inhibitory receptors,
and so when you take the alcohol away, all of a sudden the central nervous system
is overexcited and this can lead to major problems during the withdrawal phase and
I wanna review that a little bit more. So if somebody’s coming in and they’re in alcohol withdrawal,
you wanna be really careful to make sure that you’re medically evaluating them
for some of the problems that can come along. Check them for irritability, sleep trouble,
any kind of infective process. You wanna check their sensorium and see if they might be delirious.
Check if they’re disoriented. You really need to monitor this patient for seizure
which is a really serious and significant side effect of alcohol withdrawal
and also check them for hallucinations which can be a key indicator
to a very bad withdrawal problem. Delirium tremens is the most serious form of alcohol withdrawal.
It can begin within 72 hours of cessation of drinking. So remember this is a patient
who’s been drinking heavily all of a sudden stops and now their central nervous system
is just excited and lit up because they no longer have the inhibitory effects
from alcohol and so then 72 hours this patient might start to have visual and tactile hallucinations.
They may get a very severe tremor, autonomic instability where their vital signs
go haywire and they can have alternating levels of psychomotor activity.
This is very dangerous and you wanna assess this patient by checking their vital signs,
ensuring their airway, breathing and circulation, get a head CT scan,
and check them physically for any signs of hepatic failure. You can also monitor them
by doing what’s called the CIWA scale. The idea of the CIWA is that you’re initiating it
in hopes to prevent something like DTs or delirium tremens.
So this is the clinical institute of withdrawal from alcohol assessment
and here you’re monitoring patients for subtle signs that could be clues they're leading up
towards DT. So you’re checking them for vital sign and stability.
You’re checking them for headaches. You’re checking them for nausea and vomiting
and if their scoring high on the CIWA, you’re going to preemptively treat them
with a benzodiazepine to help slow down that excitation in their central nervous system.
So the differential diagnosis for someone going through withdrawals are gonna be
an alcohol induced hypoglycemia, psychosis, encephalitis, a thyrotoxicosis,
anticholinergic poisoning and also withdrawal from a sedative or hypnotic drug
because not only can alcohol induce a withdrawal problem, patients who are withdrawing
from medication especially benzodiazepines can also have a very similar looking withdrawal syndrome.
When it comes to treating DTs or delirium tremens, you wanna give a tapered dose
of a benzodiazepine and this is gonna work by helping to inhibit the central nervous system
a little bit so it’s not quite so excited. You're gonna give them the vitamin, thiamine.
You’re also gonna give them some folates, a multivitamin and magnesium sulfate
for any post withdrawal seizures.