Drug Overdose and Poisoning Flashcards
Where does toxic exposure of fumes most commonly occur?
THE HOME, can be from improper mixing of household cleaners or malfunctioning appliances that release carbon monoxide
What are the most common routes of exposures to toxins?
Ingestion, inhalation, and injection.
What is the most common form of poisoning that occurs in the home?
Children ingest medications or household cleaners
What can go hand-in-hand with substance abuse in a lot of cases?
Metal illness
What are some commonly abused substances?
nicotine, alcohol, heroin, mary-j, narcotics, amphetamines, benzos, cocaine
What is the reversal agnet for opioids?
Naloxone (narcan)
Reversal agent for benzos?
Flumazenil (romazicon)
What is the reversal agent for tylenol?
Acetylcystine (mucomyst)
What is the reversal for warfarin?
Vitamin K
What is the reversal for heparin?
Protamine sulfate
What is the risk of using flumazenil to reverse an overdose on benzos?
The potential to unmask contolled seizures, ESPECIALLY IF THEY ARE TAKING MEDICATIONS THAT LOWER THE SEIZURE THRESHOLD ALREADY, ALSO IF THEY ARE DEPENDENT ON BENZOS ALREADY
What are the two questions that should be asked when triaging an overdosing or poisoned client, IN ORDER?
Is the patents life in immediate danger?
Is the patients life in potential danger?
If the clients life is in immediate danger from poisoning or overdose, what should IMMEDIATELY be done?
Stabilization through ABCs.
What are the things to assess when obtaining patient history regarding overdose or poisoning?
Identify the drug or toxin
The time and duration of exposure
Treatment given before arrival at hospital
allergies
underlying disease processes or related injuries
THIS INFO CAN BE OBTAINED FROM: PATIENT, FAMILY MEMBER, FRIENDS, RESCUERS, BYSTANDERS
What is a toxidrome and what are the four that are listed in the book?
A group of signs and symptoms associated with overdose or poisoning to a particular group of drugs or toxins.
Anticholinergic, Cholinergic, opioids, sympathomimetic
What are the signs of a anticholinergic toxidrome?
delirium
dry, flushed skin
dilated pupils
elevated temperature
decreased bowel sounds
urinary retention
tachycardia
What are some common causes of anticholinergic toxicity?
antihistamines
atropine
jimson weed
What are some signs of a cholinergic toxindrome?
excessive salivation, lacrimation, urination, diarrhea, and emesis
diaphoresis
bronchorrhea
bradycardia
faciculation
CNS depression
constricted pupils
What are some agents that may cause a cholinergic overdose or poisoning?
organophosphate insecticides, carbamate insecticide
What are some signs of an opioid toxindrome?
CNS depression
respiratory depression
constrited pupils
hypotension
hypothermia
What are some signs of a sympathomimetic toxindrome?
agitation
tachycardia
HTN
seizures
metabolic acidosis (Rhabdo!!)
What are some things that can cause a sympathomimetice overdose or poisoning?
amphetamines, cocaine, theophylline, caffeine
What are some things that can cuase an opioid toxindrome?
opiates (codeine, morphine, propxyphene, heroin)
diphenoxylate (diphenoxylate/atropine sulfate (lomotil))
Other than the physical examination and history. What is another important item in the assessment of a poinsoned or overdosed patient?
LABS: electrolytes, hepatic function, UA, ECG, serum osmolality
ALWAYS GET AN ACETAMINOPHEN LEVEL ON OVERDOSED CLIENT
What are the eight things that are involved in the stabilization of the client experiencing an overdose or poisoning?
Airway patency
Breathing
Circulation
cardiac function
acid-base balace, electrolyte homeostasis
mentation
injuries associated with toxic exposure and underlying disease process
vitals and temperature
What are some concerns with ABCs in regards to stabilization of an overdosing or poisoned client?
Airway patency - protection may be required through endotracheal of nasotracheal intubation
breathing - many drugs or toxins can suppress the respiratory drive, mechanical respirations may be necessary
circulation - shock can occur from fluid loss as well as fluid overload, all of this depends on the hearts ability to deal with these changes as well as the hydration status of the client (examples: some snake bites cause third spacing around the area of the bite, leading to hypovolemia, some drugs impair myocardial contractility leading to fluid volume overload)
What are some concerns when it comes to cardiac function and overdose or poisoning, specifically electrically?
ECG monitoring may be necessary to monitor for cardiotoxic effects, some drugs cause conduction delays or abnormalities.
Monitoring ECG is crucial, unconscious patients often lead to unreliable information about drugs that are involved
What type of acidosis commonly occurs with overdose or poisoning?
Metabolic
What lab tests would be ordered to assess for salicylate poisoning?
electrolytes -
ABGs
salicylate levels
What two things can also change the mental status of a client other than an overdose of drugs or poisoning?
HYPOGLYCEMIA AND HYPOXEMIA
After ocular exposure, what is the initial way of decontaminating?
flushing to remove the agent with lukewarm water or NS for 15 minutes while blinking eyes open and closed
What is an initial wat to decontaminate after a dermal exposure?
flood the skin with lukewarm water for 15-30 minutes, removing all contaminated clothing beforehand, after flooding skin for 15-30 minutes wash the area gently with soap and water and rinse thoroughly.
What changes in protocol are made for organophosphate insecticides with dermal exposure?
three separate soap and water washings or showers are recommended.
Is neutralization of agent recommended?
NO, this can cause chemical burns.
What is the initial way to decontaminate from inhalation exposure?
Go to fresh air as fast as possible
How do you initially decontaminate from ingestion exposure?
use milk or water (8oz) to dilute the agent
When is dilution of ingested agent not recommended?
seizures, depressed mental status, loss of gag reflex
Is neutralization recommended for ingestion exposure?
NO NO NO NO
When is chelation indicated, what is chelation? What are some examples of chelating agents? (enhanced elimination)
Chelation is the use of binding agents to remove toxic levels of metals from the body, such as mercury, lead, iron, and arsenic.
dimercaprol, calcium disodium edetate, succimer, and deferoxamine
Is chelation a simple procedure?
NO, there are several concerns regarding this procedure.
What are some different ways to decontmainate the GI tract more extensively?
Gastric lavage - NS administered in bolus through large NG to stomach and then drained.
adsorbents - activated charcoal (often mixed with 70% sorbitol), attracts and holds agents, contraindicated in decreased bowel sounds or bowel obstruction
cathartics - substance that promotes bowel movement, usually an adjunctive therapy, magnesium citrate or 70% sorbitol are commonly used.
whole-bowel irriagtion - large volumes of polyethylene glycol with electrolytes rapidly (1-2L/H) to mechanically irrigate the bowel without electrolyte disturbance, this is also used as bowel prep for colonoscopy.
What does alteration of urine pH do? (enhanced elimination)
alkalinizing the urine increases the excretion of weak acids by increasing the amount of ionized rug in the urine. also called ION trapping.
What is multiple dose activated charcoal usually reserved for? (enhanced elimination)
aspirin, valproic acid, and theophllyine
When is hemodialysis indicated for overdoses or poisonings? (enhanced elimination)
When more conservative methods (gastric lavage, activated charcoal, antidotes) have failed, or when the client has decreased renal function.
What things are easily removed through hemodialysis?
ethylene glycol (antifreeze), methanol, lithium, salicylates, theophylline
Describe hyperbaric oxygen (HBO) therapy and when it is indicated.
oxygen is administered at a pressure higher than sea level, commonly used in carbon monoxide poisoning
How does HBO therapy effect carbon monoxide elimination?
RA half-life is 5-6 hours
100% O2 half-life is 90 minutes
HBO therapy half-life is 20 minutes
What are some complications found in HBO therapy?
otalgia
sinus pain
tooth pain
tympanic membrane rupture
confinement anxiety
convulsions
tension pneumo
What is the difference between an antagonist, antivenin, and antitoxin?
antagonist - counteracts action of another drug
antitoxin - neutralize a toxin
antivenins - antitoxin that neutralize the venom of offending snake or spider
What is a popular antivenin used in the US? What does it do?
CroFab - removes Fc fragments and leaves only fab fragments of immunoglobulin
How do you administer CroFab?
4-6 vials over 60 minutes within 6 hours of bite if possible
THEN
4-6 additional vials if no initial control of envenomation syndrome
THEN
2 vials every 6 hours for up to 18 hours (3 doses) after initial control has been established
What are some side effects of CroFab?
anaphylaxis - contraindicated in papaya or papain allergy, start slowly over the first 10 minutes with a rate of 20-25 ml/hr and observe closely for reaction
DO NOT LEAVE BEDSIDE IN THIS SITUATION
How would we continuously monitor a poisoned or overdosed client? Why? Examples?
ECG - TCAs for example can cause dysrhythmias or conduction delays
Radiology - some substances are radiopague and can be visualized with contrast CT (heavy metals, button batteries, modified release tablets or capsules, aspirin concretions, cocaine or heroin containers), also show evidence of aspiration or pulmonary edema
electrolytes, ABGs, labs - can effect electrolytes, ventilation and oxygenation changes effects ABGs and pulse oximetry, also CK, glucose, CBC, and UA should be monitored
Anion gap (8-16 mEq/L) - elevation indicates toxic exposure possible metabolic acidosis (iron, isoniazid (INH), lithium, lactate, carbon monoxide, cyanide, toluene, methanol, metformin, ethanol, ethylene glycol, ASA, DKA, uremia, seizures, starvation
osmolal gap - difference between measured and calculated osmolality, increased (>10) is abnormal. ethanol, ethylene glycol, methanol
toxicology screens - tests for specific drugs or toxins, some may not be cuaght on screen due to how they are metabolized, some are measured through metabolites (like cocaine - benzoylecgonine in urine), these tests can be done through saliva, hair, and spinal fluid, but are more commonly used through blood and urine. drug abuse screens screen for common street drugs while a coma panel checks for CNS depressive drugs.
What are some patient teaching points for toxic exposures?
Childproofing home
carbon monoxide detectors
Lead poisoning
What are some lead poisoning teachings that are given in the book?
commonly found in old homes, paint, plumbing, and dinnerware
excreted slower than absorbed, buildup occurs easily
high level accumulation is often found too late, after learning disabilities and other poor effects are diagnosed because of lack of blood level screening
children can be tested for lead by their health care providers
the local health department can provide lead poisoning treatment and information about lead abatement programs
