Emergency lectures - India tox

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Transcript of Emergency lectures - India tox

Initial Approach to the Poisoned Patient

Matthew J. Madden, M.D.PGY-3

Dept. of Emergency MedicineLoma Linda University

What we will cover

• Historical data

• Initial ED management

• Toxidrome

• Toxidrome-physical exam

• Selected poisonings

Some Data

• 2001 approx. 5% of all ED visits

• 52% were pediatric patients< 6 yrs old

• Tyl/Asa= #1

• Anti-depressants- prozac, zoloft

• Street drugs- heroin, cocaine

• CVS

Candy?

Socrates

• 399 BC.

• Ingestion of Hemlock

• No cure- death in 15 min to 1 hour

Jamestown

• 1978

• Hundreds died after ingestion of Cyanide

• Multiple ways to take

• Gas chamber

• “Almond” odor in 20-40%

Toxidromes

• Collection of signs and symptoms observed after an ingestion of a particular substance

• “Fingerprint”

• Helps establish type of ingestion

Initial approach

• Protect ED personal- may be doctors, nurses, RT’s, police, fire department, etc

• ABC’s- (How come the Americans always say this?)

Initial approach

• Most patients will have an altered sensorium

Differential Dx

• Infection

• Sepsis

• Hypoglycemia

• Hypothermia

• Hypoxia

• Uremia

• Electrolyte/Endocrine

Initial approach

• ABC’s

Initial approach

• ABC’s

• History

Initial approach

• ABC’s

• History

• VS and exam

Initial approach

• ABC’s

• History

• VS and exam

• “Coma Cocktail” and Activated Charcoal

Initial approach

• ABC’s

• History

• VS and exam

• “Coma Cocktail” and Activated Charcoal

• Lab studies and ancillary data

Initial approach

• ABC’s

• History

• VS and exam

• “Coma Cocktail” and Activated Charcoal

• Lab studies and ancillary data

• Cardiac monitor/ EKG

History

• What?

• How much?

• When?

• Witnesses?

• Anything else? (drugs?)

• Prior attempts?

• Where is the family?

VS and Exam

• Rectal Temp- must know if hyperthermic

• BP

• HR- bradycardia

• RR- is it extremely low?

• O2%

Toxidrome-Oriented Physical Exam

• Neurologic exam- pupils, mental status• Skin- dry vs wet• Lungs• Examine for bowel sounds- hyper vs hypo-active

• Essentially an exam of the Autonomic NS

Autonomic Nervous System

• Controls heart rate, blood pressure, pupil size, sweating, smooth muscle (bronchioles) GI/GU peristalsis

• Balance of parasympathetic/sympathetic influences

• Drugs or toxins can stimulate or suppress parts of ANS producing syndromes suggestive of certain toxin groups

Coma Cocktail

• DON’T

• Dextrose

• Oxygen

• Narcan

• Thiamine

Charcoal

• Created by firing various organic material (wood)

• Steamed at 900 degrees to “activate”• Large surface area and absorbs toxin in gut

preventing further absorption• Creates a “gradient” for blood to gut

transport• Does NOT work for Lithium, Lead, Iron,

Potassium, acids/alkalai

Toxidromes

• Cholinergic

• Anticholinergic

• Sympathetomimetic

• Opioid

Cholinergic

• Organophosphates

• Is this common in India?

• SLUDGE

• Parasympathetic and Sympathetic (secretions)

• Supportive care

• Atropine and 2-pam

Anticholinergic

• Atropine like compounds- jimsonweed, antihistamines, belladonna, antidepressants-TCA’s

• Muscarinic receptors

• Block cholinergic system

Anticholinergics

• Hot as a Hare- hyperthermic

• Red as a Beet- flushed skin

• Dry as a Bone- no sweat

• Blind as a Bat- myadriasis

• Mad as a Hatter- hallucinations

Anticholinergics

• Other findings- no bowel sounds

• EKG- sinus tach most common, beware of TCA’s

• Labs- normal

• Test for other toxic components

Anticholinergics

• Treatment- supportive care is usually the only thing required.

• Activated charcoal

• Benzodiazepines- lets make them nice and relaxed

• Cooling measures

Sympathomimetics

• Sympathetic overload

• Hypertension

• Tachycardia

• Hyperthermia

• Mydriasis

• Anxiety/ Delirium

• Wet skin

Sympathomimetics

• Can cause dysrhythmia’s

• Some examples include cocaine, amphetamines, ecstacy, diet pills (ephedra)

• These compounds either directly stimulate sympathetic system or release nor-epi or epinephrine

Cocaine

• Extract of Erythroxylon coca

• Water soluble

• Smoked, injected, snorted

• Ether extraction produces smoked form

• Nasal 30 min to 1-3 hours

• IV/Smoked 30sec to 30min

Clinical Use

• Used for nasal surgery

• Excellent topical anaesthetic and vasoconstrictor

• Blocks fast Na+ channels

Adverse effects

• Psychomotor agitation

• Cardiac- aortic dissection, hypertensive emergencies, MI from vasoconstriction

• Rhabdomyolysis

• Dysrhythmia

• Packers vs Stuffers

Dysrhythmia

• Shock resistant Vfib/Vtach

• QRS prolongation

• Qtc prolongation

Treatment

• Supportive

• Nitro

• Benzo’s

• NaHCO3- Why?

• Alpha antagonist

• No Beta blockers

• EKG, cardiac enzymes

Opioid

• Heroin, codeine, propoxyphene (darvocet)

• Characterized:–Neurologic depression

–Pinpoint pupils

–Respiratory depression- key

Opioid

• Any drug with morphine like quality

• IV/Oral/Transdermal/SQ

• Characteristic toxidrome as described

Opioid - Treatment

1. AIRWAY, O2 - Wait on intubation until you assess effects of Narcan

2. IV3. D50W(Coma of unknown cause)4. Naloxone (Narcan) Titrate with respiratory rate5. If no response to Narcan, pt may need

intubation

Management

• Narcan- should you use to diagnose only or to treat as well?

• T 1/2 20-60 min.

• How long does heroin last? (4-5hrs)

• Up to 4 hours or longer for normal hospital doses

Opioid

• Further studies may include basic labs, urine drug screen, ekg, head ct

Complications

• IV drug use- HIV/Hep C, Bacterial infections, endocarditis, shooter’s abscesses, fecal impaction, gas gangrene

• Seizures- demerol

• Pulmonary edema

Non- Toxidrome Toxicology

• Same approach- but can be much harder

• Additional lab tests may include Arterial blood gases- to asses for metabolic acidosis

• Lets review the Poisonous alcohols

Alcohols

• Methanol

• Found in paint, paint thinners, etc

• Converted to Formic acid and formaldehyde by ADH

• Toxic accumulation results in retinal edema, optic papillitis

• GI irritation, CNS depression/ALOC

Alcohols

• Methanol- Wide anion gap acidosis (severe) and high osmolal gap

• Treatment includes-Fomepazole (newer agent binds alcohol dehydrogenase) dose is 15mg/kg IV load followed by 20mg/kg every 12 hours for 4 hours

• Ethanol- 0.6g/kg load then 0.11g/kg/h and keep ethanol level at 100-150 mg/dL.

Alcohols

• Definitive Tx is hemodialysis- will eliminate methanol

Ethylene glycol

• Antifreeze, coolants, deicers

• Three stages– I - appears intoxicated– II - 12- 14 hours

• Pulmonary edema

– III - 24 - 72 hours• renal failure

Ethylene Glycol

• Metabolized to glycoaldehyde

• Then to formic acid, glyoxylic acid, and oxalic acid

• Lab data reveals a wide anion gap metabolic acidosis and a large osmolal gap

• No vision changes/disturbances

Ethylene glycol

• Key finding is in the urine

• Calcium oxalate cystals

• Wood’s lamp

Initial approach

• ABC’s

• History

• VS and exam

• “Coma Cocktail” and Activated Charcoal

• Lab studies and ancillary data

• Cardiac monitor/ EKG

Case

• 25 y.o male was seen sitting on balcony 16 feet above ground earlier in day.

• “Friends” found him lying on ground, unconscious 1 hour later. They drag him to ED and leave.

• What’s your initial approach?

Case

• ABC’s

• History- nothing there

• VS and Exam

• Coma Cocktail

• Do you need labs?

Case

• You fixed him with Narcan and he wants to leave. Should you let him?

Questions?

• Remember to always do the ABC’s first