Poison (Toxicant): any substance or agent capable of

producing a deleterious response in a biological system

or living organism.

Poisoning= overdose toxicity

intoxication= toxicity due to foreign substance

All substances are poisons: there is none which is

not a poison. The right dose differentiates a poison

from a remedy.

Highly toxic chemicals can be life saving when

given in appropriate doses.

(Poisons are not harmful at a sufficiently low dose)

An apparently non-toxic chemical can be toxic at

high doses. (Too much of a good thing can be bad!).

“Synthetic” does not meantoxic or poisonous

“Natural” does not meansafe or even low risk

Poisoning episodes

Accidental:Children less than 5 years by sugar coated tablets.Inhalation of organophosphorus pesticides.Overdose.

Suicidal: in response to depression or specific life events.

Homicidal

Parasuicide: attention seeking behavior or attempt at suicide.

It is typically classified as a low lethality method i.e. aim is not death

Routes of toxicant entry:

• Injection:

Through cuts or hypodermic needles into the skin, usually cause highest blood conc

• Inhalation:Through mouth/nose into respiratory system, 2nd highest blood level concentration.

• Ingestion:

Through mouth into stomach and GIT, produces 2nd lowest blood level.

• Dermal (Skin):

By absorption through skin membrane, lowest in blood level

Management of Toxicity

Management Principles:

Immediate and supportive measures.

Absorption prevention.

Elimination of toxicant.

Specific antidote.

1

2

3

4

1) Immediate and Supportive measures

Ensure clear

First:

1) Immediate and Supportive measures

Ensure clear

= Airway

= Breathing

= Circulation

It is of 1st

priority

First:

1) Immediate and Supportive measures

Causes of air way obstruction:

Mucosal swelling.

Increased salivation (↓ Conscious).

Posterior displacement of the tongue.

Swallowing of foreign bodies (ex: Fish bone).

A=Air way

1) Immediate and Supportive measures

Symptoms of airway obstruction:

Dyspnea.Air hunger.

Hoarseness (stridor).Cyanosis.

Diaphoresis. Drooling.

Tachypnea.

A=Air way

1) Immediate and Supportive measures

Management of airway obstruction:

Head tilt and Chin lift maneuver.

A=Air way

Jaw thrust maneuver.

1) Immediate and Supportive measures

Management of airway obstruction:

Nasopharyngeal or Oropharyngeal intubation

A=Air way

1) Immediate and Supportive measures

Management of airway obstruction:

In case of comatosed patients:

Cuffed endotracheal intubation is required

to prevent aspiration because gag reflex

is completely absent in unconscious patients

1) Immediate and Supportive measures

Management of airway obstruction:

Excessive mucosal secretions &/or salivation:

Suction of excessive secretions by the aid of intubation.

A=Air way

In Emergency Cases:

Finally Emergency Cricothyrotomy.

1) Immediate and Supportive measures

Causes of respiratory depression:

Drug-induced respiratory depression (Sedatives & hypnotic such as barbiturates & BDZs).

Pulmonary edema & pneumonitis.

Bronchospasm.

B = Breathing

1) Immediate and Supportive measures

Management of respiratory depression:

Give supplemental oxygen

If necessary positive pressure ventilation ‘artificial respiration’·

Respiratory stimulants for severe respiratory depression

B = Breathing

1) Immediate and Supportive measures

The shock is the clinical picture in which the patient shows signs of inadequate tissue perfusion.

Symptoms of shock:

C =Circulation

SHOCK

Coma

1) Immediate and Supportive measures

Management of shock:

1-Trendlenburg position.

2-Saline Infusion.

C =Circulation

1) Immediate and Supportive measures

Management of shock:If the patient doesn't respond to 2L infusion & the signs of shock persist, the vasopressors should be used:

C =Circulation

3-vasopressors

Dopamine

Norepinephrine

N.B.1) Dopamine at low dose stimulates dopamine receptors renal & mesenteric vasodilatation.

2) Dopamine at medium dose stimulates cardiac β1 receptors ↑cardiac contractility & C.O.P.

3) Dopamine at high dose stimulates α1

receptors systemic vasoconstriction.

2-5 µg/kg/minute infusion up to 20 µg/kg/minute

0.1-0.2 µg/kg/minute.

1) Immediate and Supportive measures

After instituting ABC interventions, more detailed evaluation is required:

A. HISTORY:Collect any evidences (thrown tablets, empty bottles, any syringes, written notes .. etc).

Second:

1) Immediate and Supportive measures

After instituting ABC interventions, more detailed evaluation is required:

B. PHYSICAL EXAMINATIONS- Careful evaluation of S&S searching for toxidromes

Second:

TOXIDROMES

It is a group of signs and symptoms and/or characteristic effects

associated with exposure to a particular substance or class of substances.

Use all your senses, search for the clues

• LOOK

– Pupil Size

• FEEL

– Temperature, Sweating

• SMELL

– Alcohol

1) Immediate and Supportive measures

After instituting ABC interventions, more detailed evaluation is required:

B. PHYSICAL EXAMINATIONS- Careful evaluation of vital signs (B.P, pulse, respiration,

temperature):

Second:

Hypertension Cocaine, amphetamines … etc

Rapid respiration Carbon monoxide.

Hypothermia C.N.S depressants.

1) Immediate and Supportive measures

After instituting ABC interventions, more detailed evaluation is required:

B. PHYSICAL EXAMINATIONS

- Pinpoint miosis is a typical sign of opioids toxicity.- Mydriasis is very common with cocaine.

- Ulcers/signs of burns with corrosives.- Bitter almond odor with cyanide toxicity.- Gingival lead lines with lead intoxication.

Second:

Eye:

Mouth:

1) Immediate and Supportive measures

After instituting ABC interventions, more detailed evaluation is required:

B. PHYSICAL EXAMINATIONS

- Cyanosis may be caused by airway obstruction and methemoglobinemia.

- Hyperactive bowel sound, cramping and diarrhea are associatedwith arsenic intoxication.

Second:

Skin:

Abdomen:

2) Preventing absorption (Gut Decontamination)

It is usually not effective more than 4-6 after poison ingestion.

It is used only for orally ingested poisons.

Methods of gut decontamination:

Most clinical toxicologists recommend administration of activated charcoal.

Emesis Gastric Lavage

ActivatedCharcoal

CatherticsWhole Bowel

Irrigation

2) Preventing absorption (Gut Decontamination)

Method:By the use of syrup of ipeca.The active ingredients are two alkaloids, emetine &cephaeline.Previous popular methods (fingertip stimulation,salt water, apomorphine) are ineffective.

Dose:In children 5-15 ml ipeca syrup + 120 ml water.adults 15-30 ml ipeca + 240 ml water.The dose can be repeated if emesis has not occurred in 30 minutes.If vomiting does not occur gastric lavage or activated charcoal is decided.

EmesisFor alert Pt

2) Preventing absorption (Gut Decontamination)

Complications:

Contraindication: Children up to 6 months of age. Comatose patient because of increased risk of aspiration. Seizures (due to compromised gag reflex). Certain toxins:

Hydrocarbons& volatile substances.Corrosives (Caustics).

Ingestion of sharp objects.

Emesis

Lethargy DrowsinessProlonged vomiting

Diarrhea