Poisoning and Toxidromes: Definitions, Types & Diagnosis – Emergency Medicine | Lecturio

Summary

This lecture delves into the management of poisonings in the emergency department, highlighting the importance of recognizing and treating various toxicological syndromes. It covers the ABCs of patient assessment, introduces the concept of toxidromes for differential diagnosis, and discusses specific cases involving anticholinergic, cholinergic, sedative-hypnotic, and opioid poisonings. The talk emphasizes the need for early intervention, decontamination, supportive care, and the use of antidotes where applicable.

Takeaways

• 🚑 Poisoning is a common cause of emergency department (ED) visits, encompassing a wide range of exposures including recreational drugs, alcohol, occupational hazards, and environmental toxins.
• 🧑‍⚕️ Emergency medicine practitioners are the first line of care for poisoned patients and must be adept at managing a variety of toxicological emergencies.
• 📝 The ABCs (Airway, Breathing, and Circulation) are crucial in the assessment and management of poisoned patients, particularly due to the potential for airway compromise and respiratory depression.
• 🌡 Vital signs and a thorough neurologic assessment, including checking for hypoglycemia in patients with altered mental status, are essential components of the initial evaluation.
• 🔍 The presence of white powder around a patient's nose and mouth suggests a possible toxic ingestion, prompting a focused approach to identifying the substance involved.
• 🏥 The toxidrome concept groups clinical syndromes based on the autonomic effects of toxins, allowing for a more systematic approach to diagnosing poisoning cases.
• 👁️ Examination of the eyes, skin, secretions, and vital signs can help identify the specific toxidrome associated with a patient, aiding in the rapid narrowing of the differential diagnosis.
• 💊 Recognizing common toxidromes such as sympathomimetics, anticholinergics, cholinergics, sedative-hypnotics, and opioids is critical for the appropriate management of poisoned patients.
• 🆘 Early intubation and respiratory support are often necessary in cases of severe poisoning, particularly when patients are at risk of drowning in their own secretions or experiencing respiratory failure.
• 🛡 Decontamination is a key intervention in managing poisoned patients, aimed at preventing further exposure to the toxin and protecting both the patient and healthcare providers.
• 💉 Antidotes are available for certain types of poisoning and should be administered promptly when indicated, such as atropine for cholinergic poisoning and naloxone for opioid overdose.

Q & A

What is the definition of poisoning in the context of emergency medicine?

Poisoning in the context of emergency medicine is any illness caused by exposure to a toxic substance, which can include recreational drug or alcohol intoxication, overdoses, occupational and environmental exposures, deliberate self-harm, accidental ingestion, and even chemical or biological weapon exposures.

Why is it important for emergency medicine professionals to manage poisoning cases effectively?

It is important because poisoning is a very common cause of ED visits, and emergency medicine professionals are often the first line of care for patients exposed to toxic substances. They need to know how to manage these cases to ensure patient safety and recovery.

What does the term 'ABCs' stand for in the context of emergency medicine, and why are they particularly important in poisoning cases?

The 'ABCs' stands for Airway, Breathing, and Circulation. They are particularly important in poisoning cases because patients may be obtunded and unable to protect their airway, and they may require intubation and respiratory support.

What is the significance of the GCS score in assessing a poisoned patient?

The GCS (Glasgow Coma Scale) score is used to assess the level of consciousness in a patient. A GCS score of less than six indicates a severely impaired level of consciousness, which may necessitate intubation to protect the airway in poisoned patients.

What is the toxidrome approach in toxicology, and how does it help in identifying the class of toxin a patient might have been exposed to?

The toxidrome approach groups clinical syndromes based on signs and symptoms associated with particular classes of toxins. It helps in identifying the class of toxin by examining the patient's eyes, skin, secretions, and vital signs to determine the toxidrome and narrow down the differential diagnosis.

What are the key features of the sympathomimetic toxidrome?

The key features of the sympathomimetic toxidrome include increased heart rate, increased blood pressure, large pupils (mydriasis), and diaphoresis. Patients may also present with hyperthermia and agitation.

How does the anticholinergic toxidrome differ from the sympathomimetic toxidrome?

The anticholinergic toxidrome is characterized by fast heart rate, high blood pressure, rapid cardiac rhythm, elevated temperature, large pupils, but with dry skin and mucous membranes due to the lack of cholinergic innervation.

What are the primary symptoms of the cholinergic toxidrome?

The primary symptoms of the cholinergic toxidrome include slow heart rate, normal to low blood pressure, respiratory depression, normal or low body temperature, and small pupils (miosis). Patients will also have profuse diaphoresis and copious secretions.

How can the sedative-hypnotic and opioid toxidromes be differentiated from each other?

Sedative-hypnotic patients present with sedation and may require respiratory support, but they do not have specific pupillary changes. Opioid patients also present with sedation but will have pinpoint pupils due to their pupillary constricting effect and often have respiratory depression.

What is the importance of decontamination in the management of a patient with a suspected toxic exposure?

Decontamination is crucial to prevent further exposure to the toxin for the patient and to protect healthcare workers from secondary exposure. It involves removing contaminated clothing, cleaning the skin, and ensuring that all toxin is removed before proceeding with other interventions.

What is the role of antidotes in the treatment of poisoning, and how should they be approached?

Antidotes play a critical role in the treatment of poisoning by counteracting the effects of specific toxins. They should be used when available and indicated based on the type of poisoning. The decision to administer an antidote should be guided by the clinical presentation and, if necessary, consultation with a poison center or toxicologist.

How should healthcare professionals manage a case of suspected acetaminophen overdose?

Management of a suspected acetaminophen overdose should include early initiation of the antidote N-acetylcysteine (NAC) within eight hours of ingestion, assessment of liver function, and monitoring for signs of liver failure. GI decontamination may be considered for high toxicity ingestions within the past few hours.

Outlines

00:00

🚑 Emergency Department Approach to Poisonings

This paragraph introduces the topic of poisonings in the emergency department, emphasizing the broad range of causes including recreational drug use, occupational exposure, and biological weapons. It underscores the importance of recognizing and managing poisonings due to their high incidence in emergency medicine worldwide. The paragraph also presents a case study of a 20-year-old man found unconscious with white powder around his mouth and nose, suggesting a toxicological emergency. The ABCs (Airway, Breathing, and Circulation) are highlighted as crucial initial steps in the assessment and management of poisoned patients, with a focus on early intubation for those with compromised airways and respiratory support for those with impaired ventilation.

05:01

🔍 Identifying Toxidromes in Poisoning Cases

The second paragraph delves into the concept of toxidromes, which are clinical syndromes associated with specific classes of toxins based on their autonomic effects. It explains that recognizing these syndromes through observable findings like pupil examination, skin condition, and vital signs can help rapidly narrow down the differential diagnosis of poisoning. The paragraph also introduces traditional toxidromes such as sympathomimetics, anticholinergics, cholinergics, sedative-hypnotics, and opioids, noting that while these are common, there are other emerging syndromes like neuroleptic malignant syndrome and serotonin syndrome. The importance of understanding the pharmacology and clinical manifestations of these toxidromes for effective patient management is emphasized.

10:02

🌡️ Sympathomimetic and Anticholinergic Toxidromes

This paragraph contrasts the clinical presentations of sympathomimetic and anticholinergic toxidromes. Sympathomimetic poisonings are characterized by increased heart rate, blood pressure, and body temperature, with large pupils, normal to decreased respiratory function, and diaphoresis. Anticholinergic poisoning, on the other hand, presents with similar cardiovascular effects but is distinguished by dry skin, mucous membranes, and a lack of secretions. The paragraph provides mnemonics to aid in recognizing these toxidromes, such as 'mad as a hatter' for anticholinergic toxicity, highlighting altered mental status, dry mouth, and flushed skin.

15:04

💊 Cholinergic and Sedative-Hypnotic Toxidromes

The paragraph discusses the clinical features of cholinergic and sedative-hypnotic toxidromes. Cholinergic poisoning is marked by a slow heart rate, normal to low blood pressure, respiratory depression, and a cool or normal temperature with small pupils and profuse secretions. The mnemonic for remembering the cholinergic toxidrome includes salivation, lacrimation, urination, defecation, and emesis, indicating fluid discharge from various orifices. Sedative-hypnotic poisoning primarily presents with somnolence and potential respiratory depression, with less autonomic effect but consideration for co-ingestions. The management of these cases includes airway protection and respiratory support.

20:07

🚨 Case Studies in Toxicological Emergencies

This paragraph presents case studies to illustrate the real-life application of toxicological knowledge. A 22-year-old man with signs of cholinergic poisoning due to organophosphate exposure is discussed, emphasizing the importance of decontamination and the use of atropine as an antidote. Another case involves a 38-year-old woman with pinpoint pupils and respiratory depression, indicative of an opioid overdose, which is managed with naloxone. The paragraph highlights the urgency and specific interventions required in these scenarios, such as intubation and high-flow oxygen, to prevent fatalities.

25:08

🌡️ Anticholinergic Poisoning and Common Causes

The paragraph focuses on anticholinergic poisoning, describing a case of a 44-year-old man with symptoms like fever, tachycardia, hot and dry skin, and dilated pupils. It discusses the importance of identifying the substances ingested and the potential need for sedation and IV fluids in management. The text also mentions the use of physostigmine as an antidote in severe cases. Common anticholinergic substances found in over-the-counter and prescription medications are listed, emphasizing the risk of toxicity with excessive doses.

🛑 Management of Acetaminophen Overdose

The final paragraph addresses the specific case of acetaminophen overdose, a prevalent and serious condition that can lead to liver failure. It explains the metabolism of acetaminophen and the production of a toxic metabolite, NAPQI, which accumulates during overdose and causes liver damage. The antidote, N-acetylcysteine (NAC), is highlighted for its ability to detoxify NAPQI if administered within eight hours post-ingestion. The importance of early intervention and the use of a nomogram to guide treatment decisions for acetaminophen overdose are emphasized.

Keywords

💡Poisoning

Poisoning refers to an illness caused by exposure to a toxic substance. In the context of the video, it encompasses a wide range of scenarios including recreational drug use, occupational exposure, and accidental ingestion. The script emphasizes the importance of recognizing poisoning as a common cause of emergency department visits and the necessity for emergency medicine practitioners to be adept at managing such cases.

💡Toxic Substance

A toxic substance is any chemical that can cause harm when it comes into contact with or is ingested by a living organism. The video discusses various sources of toxic substances, such as recreational drugs, alcohol, occupational chemicals, and environmental pollutants, highlighting the broad scope of potential hazards that can lead to poisoning.

💡Emergency Department (ED)

The emergency department, often abbreviated as ED, is a hospital unit designed to provide immediate care to patients with acute illnesses or injuries. The script mentions ED as the primary setting for managing poisoning cases, emphasizing the role of ED staff in assessing and treating patients exposed to toxic substances.

💡ABCs

In emergency medicine, the ABCs refer to the initial assessment steps: Airway, Breathing, and Circulation. The script underscores the importance of the ABCs in the management of poisoning cases, as patients may have compromised airways or respiratory function due to the toxic exposure.

💡Intubation

Intubation is a medical procedure where a tube is inserted into a patient's airway to ensure it remains open and to facilitate breathing. The video script describes scenarios where patients with poisoning may require intubation due to airway obstruction or the inability to maintain adequate ventilation.

💡Toxidrome

A toxidrome is a cluster of signs and symptoms associated with exposure to certain classes of toxins. The script introduces the concept of toxidromes as a method to categorize poisoning cases based on observable clinical findings, which aids in narrowing down the potential toxic agents involved.

💡Antidote

An antidote is a substance that counteracts a poison or toxin. The video discusses the use of antidotes such as atropine for cholinergic poisoning and naloxone for opioid overdose, illustrating their critical role in the treatment of specific poisoning cases.

💡Acetaminophen Overdose

Acetaminophen, also known as paracetamol, is a common over-the-counter medication that can cause severe liver damage when ingested in excessive amounts. The script provides an example of acetaminophen overdose, detailing the mechanism of toxicity and the importance of early intervention with the antidote N-acetylcysteine (NAC).

💡GI Decontamination

GI decontamination refers to procedures aimed at removing ingested poisons from the gastrointestinal tract to prevent further absorption. The video script mentions GI decontamination techniques such as nasogastric lavage, activated charcoal, and whole bowel irrigation, and discusses the importance of weighing their benefits against potential risks.

💡Supportive Care

Supportive care in the context of poisoning involves managing the patient's immediate life-threatening conditions while addressing the underlying toxic exposure. The script emphasizes the importance of aggressive supportive care, particularly focusing on the ABCs, to stabilize the patient's condition before proceeding with more specific treatments.

💡High-Lethality Ingestion

High-lethality ingestion refers to the consumption of substances that have a high potential to cause severe harm or death. The video script discusses the importance of recognizing and promptly treating high-lethality ingestions, such as acetaminophen overdose, and seeking expert guidance to manage these critical cases.

Highlights

Poisoning is defined as any illness caused by exposure to a toxic substance, including recreational drugs, alcohol, occupational, environmental exposures, and self-harm.

The incidence of poisoning is very common in emergency department visits in the United States.

Emergency medicine practitioners must be knowledgeable in managing poisoned patients as they are often the first to encounter them.

The ABCs (Airway, Breathing, Circulation) are crucial in the assessment and management of poisoned patients, especially due to the risk of obtunded states.

Intubation may be necessary for patients with a GCS of less than six or those with compromised airways due to secretions or vomiting.

Monitoring and supporting respiratory status with oxygen supplementation is essential in cases of poisoning.

Cardiac monitoring is vital due to the potential for poisoning to cause heart rate and blood pressure alterations.

The toxidrome approach groups clinical syndromes associated with specific toxin classes based on autonomic effects.

Traditional toxic syndromes include sympathomimetics, anticholinergics, cholinergics, sedative-hypnotics, and opioids.

Sympathomimetics increase heart rate and blood pressure, often presenting with agitation and dilated pupils.

Anticholinergic toxicity presents with dry skin, dry secretions, flushed skin, and dilated pupils.

Cholinergic toxicity is characterized by profuse sweating, copious secretions, and pinpoint pupils.

Sedative-hypnotic and opioid poisonings both present with sedation, but opioids are distinguished by pinpoint pupils and respiratory depression.

Real-life case presentations illustrate the application of toxic syndrome recognition in emergency medicine.

Decontamination is a critical step in managing poisoned patients to prevent further exposure.

Antidotes such as atropine, pralidoxime, naloxone, and physostigmine are used in specific poisoning cases to counteract the effects of toxins.

Acetaminophen overdose is a common and serious problem, potentially leading to liver failure and requiring the antidote N-acetylcysteine.

A nomogram helps guide treatment decisions for acetaminophen overdose based on the ingestion time and plasma levels.

GI decontamination may be considered for high toxicity ingestions within a few hours of occurrence, with airway protection a priority.

Transcripts

[Music]

hello in this lecture we're going to

talk about the general approach to

poisonings in the emergency department

setting

so what is a poisoning briefly it's any

illness that's caused by exposure to a

toxic substance now in the emergency

department setting that's most commonly

going to be intoxication with

recreational drugs or alcohol and

overdoses with these same substances but

poisoning also includes occupational and

environmental exposures

it includes deliberate self-harm so

suicide attempts with various types of

overdoses accidental ingestion of toxic

substances and even chemical and

biological weapon exposures the

incidence of poisoning is unknown but

it's a very very common cause of Edie

visits in the United States and it's

something that you'll definitely see in

emergency medicine practice anywhere in

the world it's a really important domain

of emergency medicine expertise because

we are always the first line people who

see patients who are exposed to toxic

substances and we really need to know

how to manage them

so let's start off with a case we have a

20 year old man who is found down in the

street so he's just found unconscious in

the street lyin there he's unresponsive

on presentation to the IDI and he's got

a white powder around his mouth and nose

so that certainly should be making you

think about a toxicological

how are we going to approach the

assessment and management of this

patient will force some for most we're

gonna start with the ABCs and the ABCs

are important for every patient and

emergency medicine but with poisonings

they're especially important because

it's very common that patients are

obtunded they're unable to protect their

airway and we really need to think about

intubating them in order to ensure a

Payton airway so anytime the patient is

a GCS of less than six if they've got a

lot of pooling of secretions in their

mouth or pharynx if they're vomiting if

they're hypoxic we really want to think

about intubating early

we also want to make sure we support our

patients respiratory status so generally

we want to at minimum monitor their ox

saturation and their end tidal co2 to

make sure they're not just oxygenating

but also ventilating in addition we're

going to give supplemental oxygen as

needed and if the patient's not

oxygenating or ventilating well we're

gonna give them respiratory support

which might include non-invasive

positive pressure ventilation it might

include bag valve mask ventilation or

again we might have to go all the way to

intubation and mechanical ventilation

for respiratory failure from a

circulatory standpoint there are a

number of poisonings that can cause

alterations in the heart rate and blood

pressure and we want to make sure that

we monitor the patient very carefully so

continuous cardiac monitoring frequent

blood pressure checks good vascular

access and then for patients who are in

shock or hypotensive we want to make

sure that we are giving them IV fluids

or vasopressors support and if the toxic

exposure has caused any kind of cardiac

dysrhythmia we want to make sure we're

addressing that as well

lastly as Dee our disability or

neurologic assessment so we want to

always check a neurologic primary survey

and every patient that's going to

include GCS pupillary exam and for

extremity movement and never ever ever

forget to check a glucose any patient

with a depressed mental status always

needs to be checked for hypoglycemia all

right well like I said before our

patient probably has a toxic ingestion

given the presence of white powder

around his nose and face so as you can

see we have a variety of different

agents here that we need to think about

in poisoning of this patient so if we

just know the pharmacology and the

pharmacokinetics and all the clinical

manifestations of this convenient list

of drugs we should be able to manage

them right well obviously that's

impossible there's tons of different

medications and drugs out in the world

that patients can potentially be exposed

to and we clearly can't take a drug by

drug approach to trying to develop a

differential diagnosis in toxicology so

we use something called the tox adrims

which basically our clinical syndromes

are groupings of signs and symptoms that

are associated with particular classes

of toxin and they're all based on the

autonomic effects of the toxin in

question so basically different drug

classes will produce different autonomic

effects and you can examine the patient

to identify what toxidrome they might

have been exposed to so the assessment

of patients is based on readily

observable findings there's examination

of the eyes or pupils examination of the

skin secretions and their vital signs

and basically by looking at these four

things we can identify what toxidrome

applies to our patient and rapidly

narrow the differential diagnosis of

what substance they might have been

exposed to so the traditional toxa germs

include sympathy oh my medics

anticholinergics cholinergic s--

sedative hypnotics and opioids however

there are other toxic rooms that have

been described more recently including

neuroleptic malignant syndrome

serotonin syndrome etc so the five

traditional toxic rooms which is what

we're going to focus on today are not

comprehensive and they don't include

every possible toxic substance so let's

start off with some path oh my medics

this is a pretty easy one to understand

all the sympathomimetic do is up

regulate the sympathetic nervous system

so basically they increase the heart

rate increase the blood pressure

generally produce sinus tachycardia

although in high doses they can also

precipitate tachy arrhythmias

they don't do a whole lot to respiration

although some patients may present with

ticket Nia and many patients will

present with hyperthermia largely due to

the motor activity and agitation

associated with sympathomimetic

ingestion 'z when you examine the pupils

in these patients they'll Bemidji attics

so their pupils will be very large

their skin may be normal but diaphoresis

is quite common and their secretions are

generally going to be normal so again

this is a pretty easy toxidrome to

understand it basically involves up

regulation of the sympathetic nervous

system fast heart rate high blood

pressure

madrasahs but generally not effects on

skin or secretions

by contrast we have the anticholinergic

toxin so as you can imagine when you

block the parasympathetic nervous system

you're going to have unopposed

sympathetic innervation so a lot of the

features of the anticholinergic toxicity

sympathomimetic s-- you're gonna have a

fast heart rate a high blood pressure a

rapid cardiac rhythm and in some cases

you may have tachy arrhythmias

generally not a lot of effect on

respiration but very commonly an

elevated temperature this is actually an

important feature of anticholinergic

toxicity

much like patients with sympathomimetic

exposure you're gonna have madrasahs so

large pupils however this is where it

gets different so these patients lose

cholinergic innervation to the skin and

the mucosa so they're gonna have dry

skin and more importantly they're gonna

have almost no secretions so they're

gonna have a dry mouth they're gonna

have no tears they're gonna appear

clinically to be very dehydrated so

there's a mnemonic for the

anticholinergic toxic toxic remits mad

as a hatter because these patients will

all have altered Mental Status and

agitation blind as a bat which refers to

the very dilated pupils red is a beat

which refers to the skin flushing that

you commonly see in patients with

anticholinergic ingestion 'he's hot is a

hair and i'm not really sure why hairs

are so hot but this refers to the dry

skin and the elevated body temperature

and then lastly dry as a bone so these

patients will have dry mucous membranes

and a lack of oral and ocular secretions

now it might not surprise you to hear

that the cholinergic toxidrome is pretty

much the opposite of the anticholinergic

toxin so these patients will have a slow

heart rate a normal to low blood

pressure they'll typically be in sinus

bradycardia arrhythmias are very unusual

with this toxidrome they're gonna have

some degree of respiratory depression

typically a pretty normal temperature

although they might be on the low side

and their pupils are going to be mitotic

so there are pupils will be constricted

small so this is a really important

differentiating feature of the

cholinergic toxic rooms these patients

will be wet so their skin will be

profusely diaphoretic and their

secretions will be copious you'll see

lots and lots of secretions in the mouth

you'll see lots of tearing and that's

because that's what the parasympathetic

nervous system does it basically

innervates all of the parts of the body

that produce secretions and you can

easily remember the cholinergic

toxidrome by thinking about

fluids pouring out of every orifice so

there's a mnemonic for the cholinergic

toxidrome that includes salivation

copious oral secretions

lacrimation copious tiering urination

these patients will commonly be

incontinent of urine

defecation or diarrhea and unfortunately

that's an area where they're often

incontinent as well gie dysmotility and

emesis so basically you can imagine

there's something or other pouring out

of every orifice in this patient there's

another mnemonic

which some people prefer that it

includes diarrhea urination meiosis or

muscle weakness Branca Rhea bradycardia

Issus lacrimation and salivation now

whether or not you use these mnemonics

or however you think of the

anticholinergic toxin an easy way to

remember it again is if they have

copious secretions if there's fluid

pouring out of every orifice you want to

be thinking about the cholinergic s--

alright the sedative hypnotics are

pretty easy to understand because what

they do is cause sedation so somnolence

is going to be the primary hallmark

these patients sometimes can be so

deeply sedated that they lose their

airway protective reflexes so you do

need to consider the possibility of

intubation in some cases and respiratory

depression might also occur so sometimes

these patients require mechanical

ventilation

there's not a lot of autonomic effects

associated with this sedative hypnotics

but remember patients often take

multiple drugs at the same time so they

may have autonomic effects related to Co

ingestions or other things that they

took along with their sedative

ingestion

opioids are very similar to the sedative

hypnotics in that they produce

somnolence however they universally

produce meiosis so opioids are a very

powerful pupillary constrictor and when

you see pinpoint or very constricted

pupils you should always think about

opioids the other thing to remember

about opioids is that they very commonly

cause respiratory depression so patients

can come in APNIC or with respiratory

rates that are significantly low and

this can be a fatal event so for these

patients we need to be pretty aggressive

about treating them and restoring their

normal respiration in order to save

their lives

all right so here's a review of the

toxic germs and I'm going to highlight

some of the things that differentiate

them so you can remember sympathomimetic

s-- these patients will present

hypertensive and tachycardic and

typically their mental status will be

agitated

anticholinergic patients will look a lot

like sympathomimetic patients except

they will have very dry skin very dry

secretions

by contrast our cholinergic patients

will be copiously wet they'll have

diaphoretic skin they'll have

increased secretions and they typically

will be somnolent rather than agitated

our sedative hypnotic patients will of

course be sedated and our opioid

patients will also be sedated however

they'll present with meiosis and

respiratory depression so hopefully this

will help you keep different clinical

syndromes associated with different

classes of drugs straight and allow you

to rapidly narrow your toxicological

when you're faced with a patient who has

an exposure all right so what we're

going to do now is shift gears to a

couple of cases and we're going to talk

through how these patients present in

real life so we're gonna start off with

a 22 year old man he was like his prior

colleague found down in a shed at work

he works as a landscaper he had white

powder on his face and clothing you can

see his vital signs he his temperatures

a bit low his heart rates 55 which is

low he's a bit too kipnuk stable blood

pressure and significant hypoxia

when you listen to him his respirations

are making a gurgling sound and you look

in his mouth he's got pooled secretions

in his oral pharynx his pupils are only

2 millimeters his skin is cool and

diaphoretic and during the exam he

begins vomiting so what are we thinking

about for this patient so the easiest

way to think about it is if you've got

bodily fluids everywhere you should you

should definitely be considering

cholinergic s-- so this gentleman has

copious oral secretions he's vomiting

his skin is diaphoretic this is somebody

you want to think about a cholinergic

ingestion and in fact most exposures are

from organophosphates which are used as

pesticides so the fact that this

gentleman works as a landscaper should

further raise your suspicion as far as

the management for this guy goes I can't

overemphasize this enough you have to

decontaminate him and that is a to

prevent further exposure for him and be

to prevent you and your staff from being

exposed and getting sick as well so

you've got to decontaminate the patient

remove the clothing clean the powder off

of the skin make sure that you that you

get rid of all of the toxin before you

proceed with other interventions

these patients are definitely going to

need to be intubated early they will

literally drown in their own secretions

so management of the airway is

absolutely critical and they typically

need high flow oxygen or positive

pressure ventilation in order to

oxygenate adequately as

far as antidotes go atropine is the

antidote of choice it restores the

normal cholinergic tone and it would be

indicated in this case and you can also

use pralidoxime or 2-pam which

reactivates the acetylcholinesterase

that has been deactivated by the toxin

all right let's move on to another case

so here we have another patient who's

found down and this is a common

presentation and toxic exposures this

one is a 38 year old woman who was found

unresponsive in her bedroom by family

there were empty pill bottles next to

her bed but the family didn't bring them

with her her vital signs are as you see

them so she has a normal temperature

normal heart rate but a respiratory rate

of four and an oxygen saturation of only

eighty one percent her pupils are one

millimeter and her skin is cyanotic but

dry so what are we thinking about with

this patient again this is a pretty

classic presentation and hopefully

you've recognized this as an opioid

overdose so this is an unfortunately

very common presentation that we see in

urban areas in the United States and

it's something that has caused a lot of

deaths in recent years and is actually

increasing in terms of the frequency and

mortality associated with these events

so anytime you see a patient who

presents with pinpoint pupils and

respiratory depression you can you

should definitely have opioids at the

top of your differential these exposures

can be recreational so patients who use

opioids

recreationally like heroin or oxycodone

they may just overdo it and

inadvertently overdose themselves but

they can also represent attempted

suicide and you need to consider that

possibility in every overdose patient

the initial management really consists

of supporting the patient's respiration

so if the patient is APNIC or breathing

so slowly that their respiration is

inadequate for oxygenation you want to

initiate bag valve mask ventilation

right away now if you're not able to bag

them effectively or if they don't

respond rapidly to your more definitive

treatment you might need to intubate

them but the good news is we have a

rapidly acting antidote for opioid

overdose so usually you can bag the

patient long enough to get them

breathing again and you shouldn't need

to intubate

we definitely want to make sure that

we're giving them high flow oxygen and

restoring their normal oxygenation I

mentioned the antidote and that's

naloxone so it's an opioid receptor

antagonist that very rapidly reverses

the effects of opioids basically

naloxone will bind to the receptors and

block the opioids from exerting

influence at the cellular level

the dose of naloxone that you need for a

given overdose patient is highly

variable it really depends on how much

of the opioid they took so we're going

to titrate our naloxone to effect if a

small dose doesn't do it consider a

larger dose and if that dose doesn't do

it consider a second dose you really

want to make sure that you are

maximizing your treatment in order to

get the desired effect so there's no

one-size-fits-all formula for dosing

alright moving on to yet another case

this one is a 44 year old man with a

history of depression he's found at home

by family with altered mental status

there are a number of empty pill bottles

in the trashcan they're all

over-the-counter pill bottles the

patient is alert but he's agitated and

combative you can see his vital signs

here he's got a temperature of 38 five a

heart rate of 135

respirations of 24 blood pressure of 160

over 98 and his saturation is normal his

pupils are eight millimeters his skin is

flushed and dry and he's got dry mucous

membranes so this is a gentleman who is

febrile tachycardic to kipnuk with hot

dry skin and madrassas hopefully you

recognize this as an anticholinergic

case so he is mad as a hatter and that

his mental status is altered blind as a

bat because he's mid Reata --q red as a

beet because he's flushed hot as a hair

because he's literally hot and dry as a

bone because his mucous membranes are

dry so this is very suggestive of

anticholinergic poisoning the key thing

you want to do anytime a patient comes

in having taken pills is find out what

they took so in his case we're gonna

probably deploy the family to go back

home and bring us in these empty pill

bottles we're also going to sedate the

patient as needed to ensure they are

safety and the safety of our staff a

patient who's agitated and combative is

not going to be easy to care for in the

edy and we want to make sure that their

behavior doesn't interfere with their

appropriate medical care

we're also going to give IV fluids to

restore intravascular volume as needed

there is an antidote for anticholinergic

poisoning it's physostigmine which is an

A it'll cholinesterase inhibitor however

we don't really give this routinely and

foremost ingestions in the emergency

department we're able to just take care

of the patient with supportive care and

let the anticholinergic medicine wear

off however if the patient does have

persistent dysrhythmias seizures severe

psychosis you can consider use of

physostigmine to treat that patient as

an adjunct to their other supportive

care

now there's a lot of common

anticholinergics you know and there's a

number of over-the-counter and

prescription medications that have very

powerful anticholinergic effects that

you should be aware of so antihistamines

antiemetics

antipsychotics anti-spasmodics like

dicyclomine motion sickness remedies

muscle relaxers and tricyclic

antidepressants all have significant

anticholinergic effects and if they're

taken in doses that are higher than that

which is intended they can produce

anticholinergic toxicity so in fact for

our patient the family brought us the

pill bottles and we discovered that he

took a full bottle of Tylenol PM which

consists of acetaminophen 325 milligrams

plus diphenhydramine 25 milligrams it

was a 100 pill bottle which is now empty

giving him a total ingestion of more

than 30 grams of acetaminophen and 2 and

a half grams of diphenhydramine that is

definitely enough to give him

significant anticholinergic toxicity

but in addition to the anticholinergic

syndrome which is what brought him to

our attention we have to be concerned

about his co ingestion which is the

tylenol so tylenol is one of our high

toxicity ingestion and anytime you have

a patient who presents with a poisoning

that has high lethality potential you

always want to involve either your local

poison center or a toxicologist to get

guidance on how to manage them we don't

routinely perform GI decontamination in

patients with toxic ingestion x' anymore

but for high toxicity ingestion x' that

have occurred within the past few hours

you might consider nasogastric lavage to

get any pills or pill fragments out of

the stomach you might consider activated

charcoal in order to hopefully bind the

toxin in question and get it out of the

system through the GI tract or you might

consider whole bowel irrigation again

for patients who potentially have intact

pills that you want to flush out the

other end you

also of course want to optimize your

supportive care and if there is an

available antidote for the ingestion in

question you want to administer it

promptly

now anytime we think about GI

decontamination I want to emphasize that

we should be weighing the potential

benefit against the risk so there's

always a risk of aspiration in a patient

with altered Mental Status if we start

putting things into their GI tract so if

it's a really high lethality ingestion

and you want to decontaminate them you

should consider protecting their airway

as well if they're not sufficiently

alert to protect it on their own all

right so we're going to talk a little

bit about acetaminophen overdose which

is actually a common and disturbing

problem in the United States

acetaminophen is also known as

paracetamol and other settings and it's

a readily available over-the-counter

drug that has high lethality potential

and produces very minimum minimal

symptoms at least in the initial phase

so the way acetaminophen works or the

way that toxicity works I should say is

that the liver metabolizes the

acetaminophen into a compound called na

pqi which is highly toxic now in normal

doses of acetaminophen your na pqi is

combined in the body with files that

produces a non toxic metabolite which is

then eliminated

however in overdoses your Thyle stores

are depleted and the toxic metabolite

accumulates now the main effect of

acetaminophen is liver injury so in high

doses acetaminophen can actually cause

fulminant liver failure and it's one of

the leading causes of liver

transplantation and young people the

antidote for this is called nak or an

asset eel cysteine and basically what it

does is it detoxifies na p Qi

decreases the production of it it's a

very very effective antidote but it has

to be given early it should be initiated

within eight hours of the ingestion so

this is very important you can't wait

around to see if the patient is going to

have manifestations of liver failure

you need to initiate treatment based on

your clinical suspicion

so there's a nomogram that helps guide

our decision about whether to give Knack

to patients with acetaminophen overdoses

note that the nomogram doesn't start

until four hours after the ingestion so

it takes four hours for gie absorption

to be complete meaning we don't check a

level until four hours after the

ingestion after that point depending on

what level we get we can differentiate

between high risk of toxicity and low

risk of toxicity and if the patient is

above that threshold for toxicity we

want to go ahead and treat them

all right so obviously I couldn't cover

every possible poisoning so I tried to

give you some essential principles it's

really important to know your toxic

drums so that you can recognize what

drug class your patient might have been

exposed to and narrow your differential

diagnosis otherwise you're going to be

left trying to figure out the individual

properties of lots of different drugs

which is not really realistic you want

to make sure you externally

decontaminate your patient in order to

protect you both yourself and them you

want to provide aggressive supportive

care with a real focus on the ABCs you

want to recognize any potential high

toxicity or high lethality ingestion x'

and get help you want to consider G

ican't decontamination especially in

patients with a high risk of morbidity

or mortality from their toxic ingestion

but remember to always protect their

airway when you do that and then you

want to be aware of antidotes and use

them when they're available and

indicated

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