THE SPIRAL CURRICULUM

General Principles in theEmergency Management of the

Acutely Poisoned Patient(one more time)

Allan R. Dionisio MD

What are the 6 principles in the approach to the poisoned patient?

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

When should you not give oxygen to a poisoned patient?

What is the IV fluid of choice in treating poisoned patients?

Emergency Stabilization

Maintain adequate airway Provide adequate oxygenation/ventilation

Exceptions: watusi. paraquat Maintain adequate circulation

Starting fluids: NSS in adults, 0.3 NaCl in children

If a previously well patient has seizures, and he has no history of epilepsy, what medication can be given as a therapeutic trial apart from the usual anticonvulsants?

Emergency Stabilization

Treat convulsions Diazepam 5mg IV

Do NOT mix with D5 containing solutions—the diazepam will crystalize

Aspirate until you get blood, then inject the diazepam, then push with plain NSS

Seizures of unknown origin--pyridoxine 80-120mg/kg

What is appropriate dose of naloxone in patients presenting with what appears to be a metabolic coma in the ER?

Emergency Stabilization Treat coma

D50-50 the single most common cause of decreased sensorium Hypoglycemia is LIFE-THREATENING!

Naloxone 2mg IV (pedia 0.1 mg/kg) Textbooks will tell you to give 0.2mg IV—good for pure

agonists but NOT EFFECTIVE for mixed agonist/antagonists

Thiamine 100mg IV To treat or prevent Wenicke’s encephalopathy

Emergency Stabilization

Correct metabolic abnormalities Electrolytes Acid-base abnormalities

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

Clinical Evaluation Time of exposure

Most ingestions beyond 2 hours are not worth decontaminating

Clinical effectiveness of gut decontamination appears to be insignificant beyond 1 hour post-ingestion

Exceptions: meds that slow down gut motility- ex. Loperamide Slow release meds—ex. Verapamil SR Enteric coated preparations—ex. Enteric coated aspirin

Clinical Evaluation

Mode of exposure—tells you what to decontaminate

Intake of other substances always keep co-ingestants in the back of your

mind Look for incongruences between ssx and hx

Circumstances prior to poisoning Get MULTIPLE testimonies

Clinical Evaluation Current medications AND past medical history of

patient and family Most suicidals get anything within reach Most children get anything within reach

Any home remedies taken Milk makes lipophilic toxicants get absorbed faster (ex.

Benzodiazepines) Egg yolk enhances watusi/firecraker absorption Aspiration pneumonia is frequent in kerosene/hydrocarbon

ingestions given household emetics

What toxicant can smell this way? Bitter almonds Fruity odor Oil of wintergreen Rotten eggs Garlic Mothballs

Clinical Evaluation--Odors

Bitter almonds--cyanide Fruity odor--DKA, isopropyl alcohol Oil of wintergreen--methylsalicylate Rotten eggs--sulfur dioxide, hydrogen sulfide, Garlic--arsenic, zinc phosphide, watusi Mothballs--camphor

Clinical Evaluation--Colors

Red skin— Gray gums— Green urine— Blue skin and lips— Cherry red lips—

Clinical Evaluation--Colors

Red skin—rifampicin, anticholinergics Gray gums—lead, mercury Green urine--formaldehyde Blue skin and lips—methemoglobin Cherry red lips—carbon monoxide

LEAD

OTHER TOXIC EFFECTS:

Abdominal colic Gingival lines

Pay attention to autonomic ssx

3 toxicants that can cause hypertension

Clinical Evaluation--HPN

C cocaine T theophylline S sympathomimetics C caffeine A anticholinergics N nicotine

3 toxicants where hypotension is the prominent effect

Clinical Evaluation--Low BP

C clonidine R reserpine and other antihypertensives A antidepressants S sedative-hypnotics H heroin and other opiates

3 toxicants that present primarily as bradycardia

Clinical Evaluation--Bradycardia

P propranolol and other beta blockers A anticholinesterases C clonidine, calcium channel blockers E ethanol D digitalis

3 toxicants that can cause mydriasis

Clinical Evaluation--Mydriasis

A antihistamines A antidepressants S sympathomimetics I isoniazid A anticholinergics

3 toxicants that present as miosis

Clinical Evaluation--Miosis

C cholinergics, clonidine O opiates, organophosphates P phenothiazines, pilocarpine S sedative-hypnotics

Toxidrome

Hot as a hare Dry as a bone Red as a beet Blind as a bat Mad as a hatter

Toxidrome

D diarrhea, diaphoresis U urinary incontinence M miosis, muscle fasciculations B bradycardia, bronchoconstriction E emesis L lacrimation S salivation

Toxidrome

Seizures Coma Acidosis

Toxidrome

Mixed metabolic acidosis and respiratory alkalosis in an unknown poisoning

Tinnitus Tachycardia

Lab exams

5-10ml heparinized blood 5-10 ml clotted blood 100 ml urine Gastric aspirate

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

Elimination of Poison:External Decontamination

Dermal: discard clothing; bathe with alkaline soap

Eye: irrigate with free flowing water for 30 minutes

Avoid neutralizing solutions in caustic exposures.

Protect yourself!

Correct dose of activated charcoal and sodium sulfate

Elimination of Poison:Gastric Decontamination

Insert NGT; Trendelenburg position Lavage with NSS Activated charcoal

Adults: 100g in 200ml water Children: 1g/kg as a slurry

Sodium sulfate Adults: 15g in 100ml water Children: 250mg/kg as 10% solution in water

2 toxicants where activated charcoal is not effective

Elimination of Poison:Gastric Decontamination

Contraindications to NGT/lavage Caustics, kerosene less than 1ml/kg, frank

convulsions Charcoal

Not effective for: alcohol, cyanide, iron, lithium, petroleum distillates

Contraindicated in: watusi, caustics

2 contraindications for giving sodium sulfate

Elimination of Poison:Gastric Decontamination

Sodium sulfate is contraindicated in: caustics, ileus, electrolyte imbalance, patients with heart failure patients with kidney failure

Alternative is sorbitol 1-2g/kg

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

Elimination of Poison:Multiple Dose Activated Charcoal Adults: 50g in 150ml water retained in

stomach q6h PO or per NGT x 48h Children: 0.5g/kg as a slurry q6h PO or per

NGT x 48h Give sodium sulfate every morning to

evacuate the charcoal.

3 toxicants where multiple dose charcoal is effective

Elimination of Poison:Multiple Dose Activated Charcoal Salicylates Methamphetamine and ecstasy Diazepam and other benzodiazepines Phenobarbital Digoxin

Elimination of Poison:Multiple Dose Activated Charcoal Carbamazepine Dapsone Phenobarbital Quinine theophylline

Elimination of Poison:Multiple Dose Activated Charcoal Amitriptyline Dextropropoxyphene Digitoxin and digoxin Disopyramide Nadolol Phenylbutazone Phenytoin Piroxicam sotalol

When do you alkalinize and when do you acidify the urine?

Elimination of Poison:urine pH manipulation

Alkalinize for weak acids: Salicylates, barbiturates, INH

Acidify for weak bases: Amphetamines, phenytoin, theophylline

How do you alkalinize and how do you acidify the urine?

Elimination of Poison:urine pH manipulation

To alkalinize--Sodium bicarbonate 1mEq/kg/dose until urine pH > 7.5

To acidify--Ascorbic acid 1g (pedia 20mg/kg) IV q6h until urine pH< 5.5

2 pharamacokinetic parameters that say dialysis is possible

Elimination of Poison:Dialysis

Low volume of distribution Low protein binding Toxin is dialysable Benefit outweighs risks of dialysis

3 dialysable toxicants

Elimination of Poison:Dialysis

Barbiturates Ethylene glycol INH Lithium Ethanol, methanol, isopropanol Salicylates

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

Antidotes: Pyridoxine (Vit B6)

Specific antidote for INH poisoning Give IV bolus dose equal to amount of INH

ingested If dose of INH is not known, give 120mg/kg

of pyridoxine and repeat as necessary to control seizures

As much as 52g has been given safely

Antidotes: Pyridoxine

Maintain on 10mg/kg/d in 3dd x 6wks If Vit B1/B6 combination, do not give more

than 1g of Vit B1 at any one bolus; repeat every 5 minutes until total required B6 is given

What is atropine the antidote for? What are the atropinization parameters?

Antidotes: Atropine

Physiologic antidote for cholinesterase inibitors

1-2mg (pedia 0.01mg/kg) IV q15min until HR > 100 Pupils > 4mm Dry oral mucosa Hypoactive bowel sounds

Antidotes: Atropine

Once fully atropinized, gradually increase intervals--speed of downloading the dose depends on whether carbamate or organophosphate

WOF: hyperpyrexia, tachyarrhythmias, hallucinations, flushing. Stop atropine and hydrate patient until symptoms wear off.

What is the antidote for opiate overdose? What is the appropriate dose?

Antidotes: Naloxone

Specific antidote for opiate poisoning 2mg IV initially. Repeat q5min until awake

or until max of 10mg total given Once awake, give 2/3 of the wake up dose

as a drip every hour

Antidote for benzodiazepine overdose

Antidotes: Flumazenil

Specific antidote for benzodiazepine overdose

Anexate 0.5mg/5ml 0.1mg in 4ml D5W IV over 15 seconds

q1min; max of 2mg Maintain on 0.1-0.2mg/hour as IV drip

General Approach

Emergency stabilization Clinical evaluation Decontamination Elimination of absorbed substance Administration of antidotes Supportive therapy and observation

80% of poisoned patients survive with aggressive supportive

therapy alone.

Your management is NOT COMPLETE unless you address

the PSYCHOSOCIAL factors leading to the poisoning.

For suicidals:Counseling

Co-mgt with Psych

Patients who attempt suicide deserve compassion, not ridicule

or condemnation.

For accidental poisoningTOXICOVIGILANCE

(home, workplace, community)

Thank you for listening.