Toxidromes in Acute Poisoning

Dr AP SamsonResident Physician

Department of Emergency Medicine

Dr AP Samson Toxidromes

What Is A Toxidrome?A toxidrome is a

combination of signs & symptoms which, when

taken collectively, characterise a suspected

toxicantToxidromic approach has been helpful

in identifying the offending agent when

dealing with an unknown substance.

Dr AP Samson Toxidromes

Bohol Incident – March 2005

Abdominal painDiarrhea

Vomiting?

Bacterialcontamination

Plant/marine toxin

Chemical contamination

Onset: 15 minutes – 3 hours (mean=2 h; mode=30 min)

B. cereus S. aureus

Cassava MushroomsShellfish/fish

PesticidesPetroleum distillatesArsenic

Signs and Symptoms

Food

Maruya (n=61)

Buchi (n=32)

Abdominal pain 22 (36.06%) 24 (75%)

Diarrhea 34 (55.74%) 8 (25.0%)

Dizziness 4 (6.56%) 11 (34.38%)

Headache 15 (24.59%) 10 (31.25%)

Malaise 4 (6.56%) 5 (15.62%)

Nausea 5 (8.20%) 0

Pinpoint pupils 39 (63.93%) 7 (21.88%)

Urinary incontinence

17 (27.87%) 4 (12.5%)

Vomiting 21 (34.4%) 12 (37.5%)

CHOLINERGIC SIGNS

Cholinesterase-

inhibitingcompound

Bohol Incident

Dr AP Samson Toxidromes

Toxidromic Approach 1. Check the

presenting signs:

• Level of sensorium • Vital signs • Pupils• Skin • Odour • Prominent symptom

Dr AP Samson Toxidromes

Toxidromic Approach

Check the presenting signs:• Level of sensorium

Toxicants that cause COMA :• Alcohols• Arsenic• Barbiturates• Benzodiazepines • Carbon monoxide

• Isoniazid• Lead• Lithium• Opioids• Phenothiazines

Dr AP Samson Toxidromes

Check the presenting signs:

•Vital signs

Blood pressureHeart rateRespiratory rateTemperature

Toxidromic Approach

Dr AP Samson Toxidromes

•Vital signs

Toxicants causing changes in blood pressure

Hypertension Hypotension

Anticholinergics Carbon monoxide

Sympathomimetics Cyanide

Cyclic antidepressants

Opiates

Caffeine Nitrites

Nicotine Sedative-hypnotics

Theophylline Anti-hypertensives

Toxidromic Approach

Dr AP Samson Toxidromes

•Vital signs

Toxicants causing changes in heart rate

Tachycardia Bradycardia

Iron -blockers

Carbon monoxide, cyanide

Anticholinesterases

Anticholinergics Clonidine

Sympathomimetics Ethanol

Salicylates Cardiac glycosides

Theophylline Opiates

Toxidromic Approach

Dr AP Samson Toxidromes

•Vital signs

Toxicants causing changes in respiratory rate

Hyperventilation Hypoventilation

Carbamates Clonidine

Organophosphates Opiates

Methanol Heavy metals

Ethylene glycol Aromatic hydrocarbons

Theophylline Digitalis

Salicylates Sedatives

Toxidromic Approach

Dr AP Samson Toxidromes

•Vital signs

Toxicants causing changes in temperature

Hyperthermia Hypothermia

Anticholinergics

MAO inhibitors Carbon monoxide

Metals Cholinergics

Phenothiazines Ethanol

Salicylates Hypoglycemics

Sympathomimetics

Sedative-hypnotics

-blockers

Toxidromic Approach

Dr AP Samson Toxidromes

Check the presenting signs:

• Pupils

Toxicants causing changes in pupillary size

Miosis Mydriasis

Cholinergics Anticholinergics

Clonidine Antihistamines

Opiates Antidepressants

Organophosphates Sympathomimetics

Phenothiazines Isoniazid

Sedative-hypnotics Meperidine

Toxidromic Approach

Dr AP Samson Toxidromes

Check the presenting signs:

• Skin Cutaneous bullae : barbiturates

Jaundice : Paracetamol, Watusi

Diaphoresis : pesticides

Hot and dry : anti-cholinergics

Flushed : alcohol

Reddish-orange: Rifampicin

Toxidromic Approach

Dr AP Samson Toxidromes

Check the presenting signs:

• Odour

Oil of wintergreen : salicylate

Garlic : arsenic,

organophosphates

Mothballs : camphor

Rotten fish : zinc phosphide

Rotten eggs : hydrogen sulfide

Toxidromic Approach

Dr AP Samson Toxidromes

Check the presenting signs:

• Prominent symptom

Seizure:IsoniazidTheophyllineCyanideCarbon monoxideTCAD

Toxidromic Approach

Dr AP Samson Toxidromes

Toxidromic Approach

2. Look for toxidromes:

Dr AP Samson Toxidromes

ComaSeizuresMetabolic acidosis

isoniazid

WHY?

Glutamic acid

GABAGlutamic aciddecarboxylase

Pyridoxal-5-phosphate

Pyridoxine Pyridoxal phosphokinase

SEIZURES

TOXIDROMES

Dr AP Samson Toxidromes

Anticholinergics

Hot has a hare (hyperthermia)Dry as a bone (dry mucosa)Red as a beet (flushed skin)Blind as a bat (dilated pupils)Mad as a hatter (confusion/delirium)

e.g. Antihistamines, scopolamine, angel trumpet, benztropine, atropine, TCADs

TOXIDROMES

Dr AP Samson Toxidromes

Diarrhea/diaphoresisUrinationMiosis/muscle fasciculationsBradycardia/bronchorrhea EmesisSalivation Lacrimation

organophosphates/ carbamates

WHY?

Acetylcholine Acetic acid + cholineAcetylcholinesterase

SalivationLacrimationUrinationDiarrheaGI crampsEmesis

TOXIDROMES

Dr AP Samson Toxidromes

TOXIDROMES

Rigidity/TremorsOpisthotonusTrismusHyperreflexiaChoreoathetosis

EXTRAPYRAMIDALSYNDROME

e.g. Haloperidol, Phenothiazines, Risperidone, Olanzapine

Dr AP Samson Toxidromes

TOXIDROMES

IrritabilityHyperreflexiaFlushingDiarrheaDiaphoresisFeverTrismusTremorsMyoclonus

SEROTONINSYNDROME

e.g. Fluoxetine, Paroxetine, Sertraline, Meperidine

Dr AP Samson Toxidromes

TOXIDROMES of Drugs of Abuse

Toxidrome LOC Pupils Heart

Rate

Respiration Others

OPIOID C Slow,

shallow

Nausea

SYMPATHETIC D BP; T

DEPRESSANT D Loss of

coordination

HALLUCINOGEN D Decreased

Pain

INHALANT D Headache.

Muscle weakness

Dr AP Samson Toxidromes

3. Look for other illnesses other than toxicologic

Toxidromic Approach

Dr AP Samson Toxidromes

Toxidromic Approach

Conditions/agents producing metabolic acidosis or elevated anion gap:

• M Methanol• E Ethylene glycol • T Toluene, theophylline• A Alcoholic ketoacidosis• L Lactic acidosis

• A Aminoglycosides• C Cyanide, CO• I Isoniazid, iron• D Diabetic ketoacidosis

• G Grand mal seizures• A Aspirin (salicylates)• P Paraldehyde, Phenformin

Dr AP Samson Toxidromes

The toxidromic approach is a helpful tool in identifying an unknown toxicant.

However, it is not the only tool.