Vol.3-Ch.8 "Toxicology and Substance Abuse" Flashcards
Since the treatments for poisoning and overdoses are always changing it is recommended that a poison control center always be called so that you can get the most updated treatment plan.
What are 3 specific reasons that it is a good idea to always call a poison control center?
- they can help you immediately determine potential toxicity based on the type of agents, amount of time exposed, and physical condition of the pt
- they can direct the most current and definitive field treatment
- they can notify the hospital of the current treatment and recommendations even before arrival of the patient
What are the 4 routes of Toxic Exposure?
- Ingestion:
MOST COMMON and usually include cleaning
agents, cosmetic, drugs, foods, household products,
petroleum based products, and plants. There can be
immediate damage from things like acids and bases
to the mouth, tongue, throat etc, but actually ingestion
mostly takes place in the small intestine. Some drugs
such as Aspirin tablets can even form together and
make a bolus that is hard to pass in the stomach and
therefore remain there for a while. - Inhalation:
Causes damage to the respiratory tract such as
edema, alveolar/capillary damage, tissue death and
once absorbed can travel to far parts of the body.
These include things like ammonia, CO, Chorine,
Cyaide, Tear gas, ect. - Surface Absorption:
Anything that gets absorbed through the skin or
mucous membrane and usually involves plants like
poison ivy/oak/sumac or Organophosphates used in
pesticides - Injection:
These usually cause immediate reactions (localized to
the immediate tissue touched) AND delayed reactions
once it gets into the system and spreads. This can
include drugs put in veins and muscles as well as
stings and bites from insects (Hymenoptera) or
animals like snakes
What are 2 obvious scene hazards when a toxic substance is involved?
- if it is a toxic substance abuser they may be agitated and dangerous, NEVER put your hand in a pocket b/c it could have used needles in it
- if there is a toxic substance or material spilled you must ensure you have the right protection to enter the area
Do not delay immediate needed care or transport while waiting for _____
Do not wait for contact or information with a poison control center! Transport and treat as needed, then get advisement on route for advances help
After basic supportive treatment have been started, next start to address the specific toxicologic emergency. The first step of this is _____ and is done via what 3 way steps?
After basic supportive treatments you should next DECONTAMINATE. This is done by:
- Reduce Intake:
This involves removing the pt from the toxic
environment or removing a stinger/needle - Reduce Absorption:
Once used was the Syrup of Ipecac or Gastric lavage
(using a tube to fill the stomach with water) but both
are not recommended as much. Ipecac made the toxic
both involved getting the pt to throw up which risks
aspiration or perforation. Very rarely does gastric
lavage work and it must be done within an hour of
ingestion. ACTIVATED CHARCOAL is the only
recommended treatment for this. - Enhance Elimination:
CATHARTICS such as Sorbitol are used to help
increase gastric motility but it is used with caution in
peds who may have a severe electrolyte shift. WHOLE
BOWL IRRIGATION is rising in popularity where a
rectal tube is used to flush the colon with a
polyethylene glycol electrolyte solution at 1-2L/hour to
clear the bowels and ensure electrolyte shifts don’t
occur
PG 330 HAS A LIST OF ANTIDOTES
PG 330 HAS A LIST OF ANTIDOTES
What information is just as important as WHAT was ingested?
What and WHEN are very important to know when dealing with an absorbed toxin (ingested may take a while where injected can be immediate)
What are the 2 main purposes of a physical exam on these pts?
- provide physical evidence of intoxication
- find any underlying illnesses that may account for symptoms or that may affect the outcome of the poisoning
What is in a “speedball”?
Heroin and cocaine
Apart from maintaining ABCs what is the second most common complication that must be maintained/prevented?
ASPIRATION (pts will have increased likelihood of vomiting and usually a decreased gag reflex, you can use advanced airways or RSI as needed)
An IV of lactated ringers or normal saline should always be administered but some departments have a “coma cocktail” of ______(x3). Should this be used for unconscious toxic patients?
NO! The solution normally has D50W, Naloxone, and Thiamine but do NOT USE just because they are asleep, use each separately as needed
What old technique for ingested toxins is no longer used?
Induces Vomiting should never be used!
It risks aspiration or for toxic substances can cause further damage on its way out
What is the main reason inhaled toxins such as “huffers” (paint or propellants, especially if in plastic or paper bags) cause irreversible brain damage?
What are the three main systems that are effected by inhaled toxins?
It mainly causes injury b/c it displaces O2 and causes hypoxia
- Central Nervous System (dizzy, headache, confusion, seizures, hallucinations, coma)
- Respiratory (tachypnea, cough, hoarseness, stridor, dyspnea, retractions, wheezing, chest pain/tightness, crackles (rales) or rhonchi)
- Cardiac (arrhythmias)
TOXIC SYNDROMES ON PG.334
TOXIC SYNDROMES ON PG.334
Toxidromes are toxins with similar _____?
Signs and symptoms
What is the #1 cause of poisoning?
Carbon Monoxide. A tasteless odorless gas that comes from the incomplete combustion of fossil fuels, charcoal, and wood. It is a very STABLE molecule
What are the 3 primary classes of sources of CO?
- ENDOGENOUS:
small amounts of CO are normally produced from
Heme Catabolism (the break down of hemoglobin) and
the normal range of this is 0.4-0.7%
(smoking will increase this significantly from 5-9
depending on how much) - EXOGENOUS:
The more common CO exposure and includes things
like house fires, automobile exhaust, or propane
fumes, etc - HYDROCARBON METHYLENE CHLORIDE:
Methylene Chloride (an organic hydrocarbon ; H2Cl2C)
is a hydrocarbon hat is often used in industrial solvents
and paint thinner. When inhaled it is converted into CO
in the liver and can cause Carboxyhemoglobinemia
that has similar signs and symptoms of CO poisoning
How does CO effect the release of NO in the body and how does that play a role in the brain and vasculature?
CO stimulates an increase in circulating NO levels. NO is a smooth muscle relaxer that causes vasodilation. After systole NO get released to cause the vasodilation of diastole to allow the blood to pass. When there is too much NO b/c there is too much CO, it CAUSES the SYNCOPE and HEADACHES related to CO poisoning.
How does CO effect O2 saturation of hemoglobin?
What is carboxyhemoglobin?
What is oxyhemoglobin?
Hemoglobin has a 200-250x higher affinity for CO than O2. It binds to the heme (iron containing complex on hemoglobin) to form CARBOXYHEMOGLOBIN causing an early release of the O2 also on that hemoglobin in the tissues and the inhibition of other O2 molecules to be taken up.
Oxyhemoglobin is what the hemoglobin is called when it is carrying O2.
How does CO effect O2 saturation of Myoglobin, and what does myoglobin usually do?
Myoglobin is an iron containing protein similar to oxygen but it is found in selected tissues (especially muscle) used for O2 storage, and is especially important in the heart
CO can displace the O2 found in myoglobin which can lead to ischemia, or arrhythmias in the heart
What is the normal half life of Carboxyhemoglobin?
How can it be reduced?
Normally Carboxyhemoglobin will be naturally destroyed and removed within 240-360 minutes (4-6hours)
100% O2 administration can reduce that to 80 minutes
Hyperbaric O2 can reduce it to 22 minutes
What are 2 main body systems that are affected by CO
The CNS and the cardiovascular system, this is b/c they are very dependent on aerobic metabolisms to which CO reduces.
CO causes DEPRESSIVE reactions in both
** as a bonus it also usually causes PULMONARY EDEMA
