1

Management of poisoningManagement of poisoning

• All poisoned patients All poisoned patients should be treated as if should be treated as if they have a potentially they have a potentially life-threatening life-threatening intoxication.intoxication.

• Treat the patient and Treat the patient and not the poison.not the poison.

2

Emergency evaluationEmergency evaluation

ABC supportive therapy:-ABC supportive therapy:-

A = A = AAirway Clearirway Clear

B = B = BBreathing Maintainreathing Maintain

C = C = CCirculation Assistirculation Assist Altered mental statusAltered mental status

DDepression or epression or EExcitationxcitation

FFever (hyperthermia) or ever (hyperthermia) or HHypothermiaypothermia

3

Emergency evaluation Emergency evaluation (cont.)(cont.)

Other complications: e.g. Other complications: e.g. RhabdomyolysisRhabdomyolysis

Clinical diagnosis:Clinical diagnosis:

- Physical examination- Physical examination

- Essential lab tests- Essential lab tests Decontamination-----To reduce Decontamination-----To reduce

absorptionabsorption Enhanced elimination----Antidote, Enhanced elimination----Antidote,

dialysis.dialysis.

4

AirwayAirway

Loss of airway protective reflexesLoss of airway protective reflexes

Airway obstruction by flaccid Airway obstruction by flaccid tongue, aspiration of gastric tongue, aspiration of gastric contents, or respiratory arrestcontents, or respiratory arrest

DeathDeath- If reflexes were lost----do - If reflexes were lost----do

endotracheal intubationendotracheal intubation

5

Endotracheal intubationEndotracheal intubation Not easy--------requires expertiseNot easy--------requires expertise Nasotracheal intubaion:Nasotracheal intubaion:

- requires local anaesthetic( lidocaine) - requires local anaesthetic( lidocaine) ----reduces pain + vasoconstrictor ----reduces pain + vasoconstrictor (phenylephrine) ----reduces bleeding(phenylephrine) ----reduces bleeding

Orotracheal intubation:Orotracheal intubation:

- requires oxygen- requires oxygen

- requires neuromuscular blocker e.g. - requires neuromuscular blocker e.g. suxamethonium ( in children suxamethonium ( in children suxamethonium induces bradycardia or suxamethonium induces bradycardia or asystole, so pancuronium is asystole, so pancuronium is recommended in children)recommended in children)

6

BREATHINGBREATHING

Breathing difficulties: major Breathing difficulties: major cause of morbidity and death.cause of morbidity and death.

Complications: 1. Ventilatory Complications: 1. Ventilatory

failurefailure

2. Hypoxia2. Hypoxia

3. 3. BronchospasmBronchospasm

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1. Ventilatory failure1. Ventilatory failure

Differential diagnosisDifferential diagnosis Differentiate poisoning from bacterial Differentiate poisoning from bacterial

or viral diseases.or viral diseases. 1. May result in brain damage, cardiac 1. May result in brain damage, cardiac

arrhythmias, and cardiac arrest.arrhythmias, and cardiac arrest.

2. Hypercarbia results in acidosis, 2. Hypercarbia results in acidosis, which may contribute to arrhythmias, which may contribute to arrhythmias, especially in patients with cyclic especially in patients with cyclic antidepressant overdose.antidepressant overdose.

8

CAUSES OF VENTILATORY CAUSES OF VENTILATORY FAILURE:FAILURE:

a) Failure of respiratory muscles e.g, bya) Failure of respiratory muscles e.g, by - Neuromuscular blockers- Neuromuscular blockers

- Organophosphates and carbamates- Organophosphates and carbamates- Botulinum toxin- Botulinum toxin

- Snake bite- Snake bite b) Depression of respiratory center e.g. b) Depression of respiratory center e.g.

by barbiturates, alcohols, opioidsby barbiturates, alcohols, opioids c) Severe pneumonia.c) Severe pneumonia. d) Pulmonary oedemad) Pulmonary oedema

9

TreatmentTreatment

11. Assist breathing manually . Assist breathing manually with a bag-valve-mask device with a bag-valve-mask device

2. Perform endotracheal 2. Perform endotracheal intubation intubation

3.Use oxygen (usually 30—35% to 3.Use oxygen (usually 30—35% to start).start).

10

2. 2. HypoxiaHypoxia

Differential diagnosisDifferential diagnosis

Differentiate from pneumonia.Differentiate from pneumonia.

11

CAUSES OF HYPOXIACAUSES OF HYPOXIA

1.1. Insufficient oxygen in air Insufficient oxygen in air (e.g. displacement of (e.g. displacement of oxygen by inert gases).oxygen by inert gases).

2.2. Disruption of oxygen Disruption of oxygen absorption by the lung (e.g. absorption by the lung (e.g. resulting from pneumonia resulting from pneumonia or pulmonary edema).or pulmonary edema).

3. Cellular hypoxia3. Cellular hypoxia

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CAUSES OF HYPOXIA CAUSES OF HYPOXIA (cont.)(cont.)

a.a. Pneumonia. The most common Pneumonia. The most common cause of pneumonia in overdosed cause of pneumonia in overdosed patients is pulmonary aspiration of patients is pulmonary aspiration of gastric contents. gastric contents.

Pneumonia may also be caused by Pneumonia may also be caused by intravenous injection of foreign intravenous injection of foreign material or bacteria, aspiration of material or bacteria, aspiration of petroleum distillates or inhalation of petroleum distillates or inhalation of irritant gases. irritant gases.

13

CAUSES OF HYPOXIA CAUSES OF HYPOXIA (cont.)(cont.)

b. Pulmonary edema:b. Pulmonary edema:

- Cardiogenic pulmonary - Cardiogenic pulmonary edema caused by Beta blockers, edema caused by Beta blockers, Cyclic antidepressants, QuinidineCyclic antidepressants, Quinidine

- Non-cardiogenic pulmonary - Non-cardiogenic pulmonary edema caused by aspiration of edema caused by aspiration of hydrocarbons (e.g. petroleum) hydrocarbons (e.g. petroleum)

14

CAUSES OF HYPOXIA CAUSES OF HYPOXIA (cont.)(cont.)

3. Cellular hypoxia: e.g. by 3. Cellular hypoxia: e.g. by carbon monoxide or carbon monoxide or methemoglobinemia, which limit methemoglobinemia, which limit binding of oxygen to hemoglobin, binding of oxygen to hemoglobin, and cyanide, which blocks oxygen and cyanide, which blocks oxygen utilization.utilization.

15

TreatmentTreatment

Correct hypoxia e.g.:Correct hypoxia e.g.:

- Administer 100% oxygen in - Administer 100% oxygen in carbon monoxide poisoningcarbon monoxide poisoning

- Give cyanide antidote kit for - Give cyanide antidote kit for cyanidecyanide

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3. 3. BronchospasmBronchospasm

Differentiate from asthma, Differentiate from asthma, hypersensitivity or allergic hypersensitivity or allergic reactions.reactions.

Severe bronchospasm may Severe bronchospasm may result in hypoxia and ventilatory result in hypoxia and ventilatory failure.failure.

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Examples of drugs and Examples of drugs and toxins that cause toxins that cause

bronchospasmbronchospasm 1.1. Direct irritant injury from inhaled Direct irritant injury from inhaled

gases or pulmonary aspiration of gases or pulmonary aspiration of petroleum distillates or stomach petroleum distillates or stomach contents.contents.

2.2. Pharmacologic effects of toxins, e.g. Pharmacologic effects of toxins, e.g. organophosphate or carbamate organophosphate or carbamate insecticides or beta-adrenergic insecticides or beta-adrenergic blockers.blockers.

3. Hypersensitivity or allergic reactions 3. Hypersensitivity or allergic reactions may also cause bronchospasm.may also cause bronchospasm.

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TreatmentTreatment

1.1. Administer supplemental oxygen.Administer supplemental oxygen. 2.2. Remove the patient from the source Remove the patient from the source

of exposure to any irritant gas.of exposure to any irritant gas. 3.3. Administer bronchodilators:Administer bronchodilators: a.a. salbutamol inhalersalbutamol inhaler b.b. If this is not effective, give If this is not effective, give

aminophylline, 6 mg/kg IV over 30 aminophylline, 6 mg/kg IV over 30 minutes.minutes.

For patients with bronchospasm and For patients with bronchospasm and bronchorrhea caused by organophosphate bronchorrhea caused by organophosphate or other anticholinesterase poisoning, give or other anticholinesterase poisoning, give atropine.atropine.

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CIRCULATIONCIRCULATION I.I. General assessment and initial General assessment and initial

treatmenttreatment A.A. Check blood pressure and pulse rate Check blood pressure and pulse rate

and rhythm. Perform cardiopulmonary and rhythm. Perform cardiopulmonary resuscitation (CPR) if there is no pulse .resuscitation (CPR) if there is no pulse .

B.B. Begin continuous Begin continuous electrocardiographic (ECG) monitoring electrocardiographic (ECG) monitoring of arrhythmiasof arrhythmias

(may complicate a variety of drug (may complicate a variety of drug overdoses).overdoses).

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General assessment (cont.)General assessment (cont.)

C.C. Secure venous access. Secure venous access.

- to draw blood for routine studies.- to draw blood for routine studies.

- to begin intravenous infusion .- to begin intravenous infusion . D. In seriously ill patients (eg, D. In seriously ill patients (eg,

hypotensive, obtunded, convulsing, hypotensive, obtunded, convulsing, or comatose), place a Foley catheter or comatose), place a Foley catheter in the bladder, obtain urine for in the bladder, obtain urine for routine and toxicologic testing, and routine and toxicologic testing, and measure hourly urine output.measure hourly urine output.

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2. Bradycardia and 2. Bradycardia and atrioventricular (AV) blockatrioventricular (AV) block

Examples of drugs and toxins causing Examples of drugs and toxins causing bradycardia or AV blockbradycardia or AV block

1.1. Membrane-depressant drugs Membrane-depressant drugs (eg, cyclic antidepressants, (eg, cyclic antidepressants, quinidine, beta blockers)quinidine, beta blockers)

Cholinergic or vagotonic agentsCholinergic or vagotonic agents - Carbamate insecticides - Carbamate insecticides - Digitalis glycosides - Digitalis glycosides - Organophosphates - Organophosphates

22

Examples of drugs and toxins Examples of drugs and toxins causing bradycardia or AV causing bradycardia or AV

block (cont.)block (cont.) Sympatholytic agentsSympatholytic agents

- Beta blockers- Beta blockers- Clonidine- Clonidine

OtherOther - Opiates - Opiates

- Calcium antagonists- Calcium antagonists- Lithium- Lithium

23

Complications:Complications:

Bradycardia and AV block Bradycardia and AV block frequently cause hypotension, frequently cause hypotension, which may progress to asystolic which may progress to asystolic cardiac arrest.cardiac arrest.

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Treatment:Treatment:

Do Do not not treat bradycardia or AV treat bradycardia or AV block unless the patient is block unless the patient is symptomatic (eg, syncope, symptomatic (eg, syncope, hypotension). hypotension).

Note: Note: Bradycardia or even AV Bradycardia or even AV block may be a protective reflex block may be a protective reflex to lower the blood pressure in a to lower the blood pressure in a patient with life-threatening patient with life-threatening hypertension .hypertension .

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Treatment (cont.)Treatment (cont.)

1.1. Maintain airway and assist Maintain airway and assist breathing. Administer breathing. Administer supplemental oxygen.supplemental oxygen.

2.2. Rewarm hypothermic Rewarm hypothermic patients. patients.

3.3. Administer atropine. If this is Administer atropine. If this is not successful, use isoprenaline not successful, use isoprenaline or an emergency pacemaker.or an emergency pacemaker.

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Treatment (cont.)Treatment (cont.) 4.4. Use the following specific Use the following specific

antidotes if appropriate:antidotes if appropriate:

a.a. For beta-blocker overdose, For beta-blocker overdose, give glucagon .give glucagon .

b.b. For digitalis intoxication, use For digitalis intoxication, use Fab fragments .Fab fragments .

c.c. For cyclic antidepressant For cyclic antidepressant overdose, administer sodium overdose, administer sodium bicarbonate .bicarbonate .

d.d. For calcium antagonist For calcium antagonist overdose, give calcium .overdose, give calcium .

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3. Tachycardia3. TachycardiaExamples of drugs and toxins causing Examples of drugs and toxins causing

tachycardiatachycardia Sympathomimetic Sympathomimetic

agentsagents Amphetamines Amphetamines

CaffeineCaffeine Cocaine Cocaine Agents causing Agents causing cellular hypoxiacellular hypoxia Carbon monoxide Carbon monoxide

Cyanide Cyanide Oxidizing agents Oxidizing agents (methemoglobinemia)(methemoglobinemia)

Anticholinergic agentsAnticholinergic agents

Antihistamines Antihistamines Atropine Atropine

Cyclic antidepressantsCyclic antidepressants Phenothiazines Phenothiazines

OtherOther Ethanol or Ethanol or sedative-hypnotic drug sedative-hypnotic drug withdrawalwithdrawal Thyroid hormone Thyroid hormone

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TreatmentTreatment

If tachycardia is not associated with If tachycardia is not associated with hypotension hypotension

For sympathomimetic-induced For sympathomimetic-induced tachycardia, give propranolol, or tachycardia, give propranolol, or esmolol, esmolol,

For anticholinergic-induced tachycardia, For anticholinergic-induced tachycardia, give physostigmine, or neostigmine.give physostigmine, or neostigmine.

Caution: Caution: Do Do not not use these drugs in use these drugs in patients with cyclic antidepressant patients with cyclic antidepressant overdose, because additive depression of overdose, because additive depression of conduction may result in asystole.conduction may result in asystole.

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4.4. HypotensionHypotension

ComplicationsComplications

Severe or prolonged hypotension Severe or prolonged hypotension can cause acute renal tubular can cause acute renal tubular necrosis, brain damage, and necrosis, brain damage, and cardiac ischemia.cardiac ischemia.

Metabolic acidosis is a common Metabolic acidosis is a common finding.finding.

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SELECTED DRUGS AND SELECTED DRUGS AND TOXINS CAUSING TOXINS CAUSING

HYPOTENSIONHYPOTENSIONHYPOTENSION WITH HYPOTENSION WITH

RELATIVE RELATIVE BRADYCARDIABRADYCARDIA

Sympatholytic Sympatholytic agentsagents

- Beta blockers- Beta blockers - Hypothermia- Hypothermia Membrane-Membrane-

depressant drugsdepressant drugs - Beta blockers - Beta blockers

(mainly propranolol)(mainly propranolol) - Cyclic - Cyclic

antidepressantsantidepressants

OthersOthers - Barbiturates- Barbiturates - Calcium antagonists- Calcium antagonists - Cyanide- Cyanide - Opiates- Opiates - Organophosphates - Organophosphates

and carbamatesand carbamates - Sedative-hypnotic - Sedative-hypnotic

agentsagents

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HYPOTENSION WITH HYPOTENSION WITH TACHYCARDIATACHYCARDIA

ArsenicArsenic HyperthermiaHyperthermia CaffeineCaffeine TheophyllineTheophylline SalbutamolSalbutamol

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TreatmentTreatment

Fortunately, hypotension Fortunately, hypotension usually responds readily to usually responds readily to empirical therapy with empirical therapy with intravenous fluids and low doses intravenous fluids and low doses of presser drugs (eg, dopamine). of presser drugs (eg, dopamine).

1.1. Maintain the airway and Maintain the airway and assist ventilation if necessary . assist ventilation if necessary . Administer supplemental oxygen.Administer supplemental oxygen.

Administer norepinephrine .Administer norepinephrine .

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Treatment (cont.)Treatment (cont.)

2.2. Treat cardiac arrhythmias Treat cardiac arrhythmias that may contribute to that may contribute to hypotension (heart rate hypotension (heart rate <40-50/min or> 180—200/mm .<40-50/min or> 180—200/mm .

3. Hypotension associated with 3. Hypotension associated with hypothermia often will not hypothermia often will not improve with routine fluid improve with routine fluid therapy but will rapidly normalize therapy but will rapidly normalize upon rewarming of the patient. upon rewarming of the patient.

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Treatment (cont.)Treatment (cont.)

4.4. Consider specific antidotes:Consider specific antidotes:

a.a. Sodium bicarbonate for cyclic Sodium bicarbonate for cyclic antidepressantantidepressant

b. Glucagon for beta-blocker b. Glucagon for beta-blocker overdose.overdose.

c. Calcium for calcium antagonist c. Calcium for calcium antagonist overdose.overdose.

d. If the systemic vascular d. If the systemic vascular resistance is low, administer resistance is low, administer norepinephrine norepinephrine

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5. Hypertension5. Hypertension

Complications:Complications:

Severe hypertension can result Severe hypertension can result in intracranial hemorrhage, in intracranial hemorrhage, aortic dissection, myocardial aortic dissection, myocardial infarction, and congestive heart infarction, and congestive heart failure.failure.

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SELECTED DRUGS AND TOXINS SELECTED DRUGS AND TOXINS CAUSING HYPERTENSIONCAUSING HYPERTENSION

HYPERTENSION WITH TACHYCARDIAHYPERTENSION WITH TACHYCARDIAGeneralized sympathomimetic agentsGeneralized sympathomimetic agents Anticholinerglc agentsAnticholinerglc agents Amphetamines and derivatives Amphetamines and derivatives Antihistamines Antihistamines Cocaine Cocaine Atropine Atropine

Cyclic antidepressantsCyclic antidepressants Epinephrine Epinephrine PhenothiazinesPhenothiazines LevodopaLevodopa OtherOther LSD (lysergic acid diethylamide) Ethanol and LSD (lysergic acid diethylamide) Ethanol and sedative-hypnotic sedative-hypnotic

drug withdrawal drug withdrawal Marihuana Marihuana Nicotine Nicotine (early stage)(early stage) Monoamine oxidase inhibitors Monoamine oxidase inhibitors Organophosphates PhencyclidineOrganophosphates Phencyclidine

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SELECTED DRUGS AND TOXINS SELECTED DRUGS AND TOXINS CAUSING HYPERTENSION (cont.)CAUSING HYPERTENSION (cont.)

HYPERTENSION WITH HYPERTENSION WITH BRADYCARDIA OR BRADYCARDIA OR ATRIOVENTRICULAR BLOCKATRIOVENTRICULAR BLOCK

ClonidineClonidine Norepinephrine Norepinephrine

Ergot derivativesErgot derivatives Phenylephrine Phenylpropanolamine Phenylephrine Phenylpropanolamine

38

TreatmentTreatment

Rapid lowering of the blood pressure is Rapid lowering of the blood pressure is desirable .desirable .

For hypertension with little or no For hypertension with little or no tachycardia, use phentolamine, nifedipine tachycardia, use phentolamine, nifedipine chewable capsule or liquid form,or chewable capsule or liquid form,or nitroprusside.nitroprusside.

For hypertension with tachycardia, add to For hypertension with tachycardia, add to the above treatment propranolol, or the above treatment propranolol, or esmolol , or labetalol.esmolol , or labetalol.

Caution: Caution: Do Do not not use propranolol or use propranolol or esmolol alone to treat hypertensive crisis; esmolol alone to treat hypertensive crisis; beta blockers may paradoxically worsen beta blockers may paradoxically worsen hypertension if it is caused primarily by hypertension if it is caused primarily by alpha stimulation.alpha stimulation.

39

ALTERED MENTAL STATUSALTERED MENTAL STATUS

• l. COMA AND STUPORl. COMA AND STUPOR• a) Causes:a) Causes:- Drugs and toxins that depress Drugs and toxins that depress

brain reticular activating brain reticular activating system(RAS)system(RAS)

- After seizuresAfter seizures- Brain injury associated with Brain injury associated with

infarction or intracranial bleeding.infarction or intracranial bleeding.

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b) Complications:b) Complications:

Respiratory depression (cause of Respiratory depression (cause of death)death)

Hypotension, hypothermia, Hypotension, hypothermia, hyperthermia and hyperthermia and rhabdomyolysisrhabdomyolysis

41

c) Treatment:c) Treatment:

-AB supportive + Oxygen-AB supportive + Oxygen -50% dextrose + thiamine( thiamine -50% dextrose + thiamine( thiamine

prevents Wernicke’s syndrome in prevents Wernicke’s syndrome in persons deficient in thiamine)persons deficient in thiamine)

Normalize body temperatureNormalize body temperature Naloxone is routinely given in Naloxone is routinely given in

respiratory depression (may ppt. respiratory depression (may ppt. opioid withdrawal)opioid withdrawal)

Flumazenil may be consideredFlumazenil may be considered

42

ll. Hypothermia:ll. Hypothermia: Serious when temp. Serious when temp. < 32 °C (90 °F )< 32 °C (90 °F )

Treatment:Treatment:

- - AB supportive + O + O22

- Rewarm slowly (to avoid rewarming arrhythmia)- Rewarm slowly (to avoid rewarming arrhythmia)

( this arrhythmia does not respond to the usual treatment of v. arrhythmia – bretylium may be effective)

43

Open cardiac massage with direct Open cardiac massage with direct warm irrigation of ventricles may be warm irrigation of ventricles may be needed in hypothermic patients in needed in hypothermic patients in cardiac arrest.cardiac arrest.

44

lll. Hyperthermia

Serious when temp. Serious when temp. > 40 °C (104 °F)> 40 °C (104 °F) A) CausesA) Causes1. Drugs and toxins: - antipsychotics(chronic use)▬►

neuroleptic malignant syndrome - halothane and

suxamethonium▬►malignant hyperthermia (inherited disorder)

- amphetamines and cocaine▬► excessive muscular activity

45

- aspirin (toxic doses)- aspirin (toxic doses)▬► uncoupling of ▬► uncoupling of oxidative phosphorylationoxidative phosphorylation

- serotonergic drugs e.g. fluoxetine ▬► - serotonergic drugs e.g. fluoxetine ▬► serotonin syndromeserotonin syndrome

- withdrawal from alcohol and sedative - withdrawal from alcohol and sedative hypnoticshypnotics

2. Other causes:2. Other causes:

heat stroke, infections, meningitis, heat stroke, infections, meningitis, thyrotoxicosis……… etc. thyrotoxicosis……… etc.

46

B. Complications:B. Complications: RhabdomyolsisRhabdomyolsis Renal failureRenal failure Cardiac failureCardiac failure Brain damageBrain damage Death Death

47

C. Treatment:C. Treatment: Immediate rapid coolingImmediate rapid cooling - AB supportive + oxygen- AB supportive + oxygen

- I.V. glucose- I.V. glucose

- control seizures, agitation or - control seizures, agitation or muscular rigiditymuscular rigidity

- continue cooling with tepid - continue cooling with tepid sponging, fanning, sponging, fanning,

or iced gastric or colonic lavage,or iced gastric or colonic lavage,

or ice water immersionor ice water immersion

48

Treatment (cont.):Treatment (cont.):

- To prevent shivering give:- To prevent shivering give:

diazepam or midazolam( central diazepam or midazolam( central muscle relaxants)muscle relaxants)

or neuromuscular blockers or neuromuscular blockers (pancuronium)(pancuronium)

- For persistent hyperthermia use:- For persistent hyperthermia use:

dantrolene (peripherally, prevents dantrolene (peripherally, prevents calcium release from sarcoplasmic calcium release from sarcoplasmic reticulum of skeletal musclereticulum of skeletal muscle

49

Treatment (cont.):Treatment (cont.):

- For neuroleptic malignant syndrome - For neuroleptic malignant syndrome use:use:

bromocriptine (dopamine agonist)bromocriptine (dopamine agonist)

- for serotonin syndrome use:- for serotonin syndrome use:

methysergide (serotonin antagonist)methysergide (serotonin antagonist)

50

lV. SeizureslV. Seizures

A) Causative drugs and A) Causative drugs and toxins:toxins:

- amphetamines and - amphetamines and cocainecocaine

- propranolol (but not - propranolol (but not atenolol)atenolol)

- camphor- camphor

- organophosphates- organophosphates

- CO or cyanide - CO or cyanide (cellular hypoxia)(cellular hypoxia)

- tricyclics- tricyclics

- haloperidol- haloperidol

- lead and other - lead and other heavy metalsheavy metals

- methanol- methanol

- salicylates- salicylates

-withdrawal from -withdrawal from ethanol or sedativesethanol or sedatives

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b) Complications:b) Complications:

-apnoea-apnoea

-pulmonary aspiration-pulmonary aspiration

-hyperthermia-hyperthermia

-rhabdomyolysis-rhabdomyolysis

-brain damage-brain damage

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C) Treatment:C) Treatment:1. AB supportive + oxygen1. AB supportive + oxygen

2. Naloxone2. Naloxone

3. If hypoglycemic, give 50% glucose + 3. If hypoglycemic, give 50% glucose + thiaminethiamine

4. Use anticonvulsants e.g.4. Use anticonvulsants e.g.

diazepam, phenytoin, phenobarbitonediazepam, phenytoin, phenobarbitone

Anticonvulsants shoud be Anticonvulsants shoud be administered slowly ( if given rapidly, administered slowly ( if given rapidly, can cause hypotension, cardiac arrest can cause hypotension, cardiac arrest or respiratory arrest)or respiratory arrest)

53

Treatment (cont.):Treatment (cont.):

- If hyperthermic: cooling; - If hyperthermic: cooling; pancuroniumpancuronium

- Use specific antidotes if possible e.g. - Use specific antidotes if possible e.g. pralidoxime + atropine for pralidoxime + atropine for organophosphatesorganophosphates

54

V. Agitation, delirium and V. Agitation, delirium and psychosispsychosisAgitation = continuous and excessive Agitation = continuous and excessive

restlessnessrestlessness

Delirium = a state of mental confusion Delirium = a state of mental confusion and excitementand excitement

Psychosis = delusions (false beliefs) + Psychosis = delusions (false beliefs) + hallucinations (false sensation) + hallucinations (false sensation) + indifference + excitementindifference + excitement

55

a) Causative drugs and a) Causative drugs and toxins:toxins:- Lead and other heavy metals- Lead and other heavy metals

- Carbon monoxide- Carbon monoxide

- L-dopa- L-dopa

- Salicylates- Salicylates

- Withdrawal from ethanol or - Withdrawal from ethanol or sedativessedatives

- Amphetamines and cocaine- Amphetamines and cocaine

- L.S.D. and marihuana- L.S.D. and marihuana

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b) Complications:b) Complications:

- Hyperthermia - Hyperthermia

- Rhabdomyolysis- Rhabdomyolysis

C) Treatment:C) Treatment:

- Rapid cooling, if hyperthermic- Rapid cooling, if hyperthermic

- Treat hypoglycemia- Treat hypoglycemia

- Give a sedative ( midazolam or diazepam) - Give a sedative ( midazolam or diazepam) or a an antipsychotic (haloperidol)or a an antipsychotic (haloperidol)

- Administer pancuronium (intubation may - Administer pancuronium (intubation may be needed)be needed)

57

Diagnosis of poisoningDiagnosis of poisoning Correct diagnosis is through data from Correct diagnosis is through data from

history, physical examination and lab. history, physical examination and lab. tests.tests.

1. History1. History - Collect history of ingestion from the - Collect history of ingestion from the

patient, family, friends patient, family, friends pharmacy…….etc.pharmacy…….etc.

- Collect any drugs or drug remnants for - Collect any drugs or drug remnants for later testinglater testing

( Rescuer should avoid skin contact or ( Rescuer should avoid skin contact or needle stick).needle stick).

58

Diagnosis of poisoning Diagnosis of poisoning (cont.)(cont.)

2. Physical examination:2. Physical examination:

Look for general signs that may lead Look for general signs that may lead to the poison (B.P., pulse, eye, skin, to the poison (B.P., pulse, eye, skin, ….etc.)….etc.)

♠ ♠ αα-adrenergic syndrome (e.g. with -adrenergic syndrome (e.g. with phenylpropanolamines)phenylpropanolamines)

B.P. + reflex bradycardia + dilated B.P. + reflex bradycardia + dilated pupilpupil

59

♠ ♠ ββ -adrenergic syndrome (e.g. with -adrenergic syndrome (e.g. with salbutamol)salbutamol)

B.P. (B.P. (ββ 2 2 vasodilatation) + vasodilatation) + tachycardia tachycardia

60

♠ ♠ Mixed Mixed αα – and – and ββ adrenergic adrenergic syndrome syndrome

(e.g. amphetamines and cocaine )(e.g. amphetamines and cocaine )

B.P + tachycardia + dilated pupilB.P + tachycardia + dilated pupil

♠ ♠ Sympatholytic syndrome ( e.g. Sympatholytic syndrome ( e.g. Clonidine, methyldopa, also opioids )Clonidine, methyldopa, also opioids )

B.P + bradycardia + pin-point B.P + bradycardia + pin-point pupilpupil

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♠ ♠ Nicotinic cholinergic syndrome Nicotinic cholinergic syndrome

(autonomic ganglia)(autonomic ganglia)

e.g. nicotinee.g. nicotine

- Initial tachycardia followed by - Initial tachycardia followed by bradycardiabradycardia

- Muscle fasciculation followed by - Muscle fasciculation followed by paralysisparalysis

♠ ♠ Muscarinic cholinergic syndrome :Muscarinic cholinergic syndrome :

(muscarine) (muscarine)

bradycardia + miosis + sweating + SLUDbradycardia + miosis + sweating + SLUD

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♠ ♠ Mixed cholinergic syndrome :Mixed cholinergic syndrome :

(e.g. organophosphates)(e.g. organophosphates)

- Pin-point pupil + SLUD syndrome- Pin-point pupil + SLUD syndrome

- Muscle fasciculation followed by paralysis- Muscle fasciculation followed by paralysis

♠ ♠ Anticholinergic syndrome :Anticholinergic syndrome :

(e.g. atropine, cyclic antidepressants, (e.g. atropine, cyclic antidepressants, antihistamines)antihistamines)

- Tachycardia- Tachycardia

- Hot dry skin- Hot dry skin

- Urinary retention- Urinary retention

63

Characteristic odours:Characteristic odours:

Examples:Examples:

Acetone acetone, Acetone acetone, chloroformchloroform

Bitter almond cyanideBitter almond cyanide

Garlic arsenic, Garlic arsenic, organophosphatesorganophosphates

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Essential clinical lab tests Essential clinical lab tests Routine tests:Routine tests:1. Serum osmolality:1. Serum osmolality: Measure Na, glucose and BUN serum Measure Na, glucose and BUN serum

concentration.concentration. 1- Calculate osmolality (calculated osmolality) 1- Calculate osmolality (calculated osmolality)

= 2[Na] + [glucose] / 18 + [BUN] / 2.8= 2[Na] + [glucose] / 18 + [BUN] / 2.8 (Normal osmolality (Normal osmolality value = 290 mosmol / L)

2- Measure serum osmolality by an 2- Measure serum osmolality by an Osmometer Osmometer (measured osmolality ) (measured osmolality )

3- Osmolar gap = measured osmolality – 3- Osmolar gap = measured osmolality – calculated osmolalitycalculated osmolality

Increased osmolar gap is seen with alcohol or Increased osmolar gap is seen with alcohol or ethylene glycol poisoningethylene glycol poisoning

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2. Anion gap:2. Anion gap: Measure Na, chloride and bicarbonate Measure Na, chloride and bicarbonate serum concentration.serum concentration. Calculate anion gap:Calculate anion gap: anion gap = [Na anion gap = [Na ++] - [CL] - [CL--] - [HCO] - [HCO3 3 -]-]

Normal anion gapNormal anion gap value = 6-12 meq / L

Increased anion gap is seen with Increased anion gap is seen with alcohol, ethylene glycol, CO, cyanide alcohol, ethylene glycol, CO, cyanide poisoningpoisoning

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Other tests:Other tests:

3. Measurement of serum 3. Measurement of serum potassiumpotassium

4. Renal function tests:4. Renal function tests:

- measure serum creatinine - measure serum creatinine and BUN levelsand BUN levels

5. Liver function tests:5. Liver function tests:

- measure liver transaminases - measure liver transaminases levelslevels

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Elimination of the poison Elimination of the poison from the GI tract, skin and from the GI tract, skin and eyes eyes

A. Gastric emptying A. Gastric emptying Syrup of IpecacSyrup of Ipecac - usually used at - usually used at

home, rarely used after presenting to home, rarely used after presenting to medical facility. medical facility. Dose: < 1 year = 1 cc/kg; 1 to 12 Dose: < 1 year = 1 cc/kg; 1 to 12

years = 15 ml; > 12 years = 30 ml years = 15 ml; > 12 years = 30 ml Follow with water or juice Follow with water or juice

(induction of emesis will be delayed (induction of emesis will be delayed if given with milk); repeat once if no if given with milk); repeat once if no emesis in 30 minutes; keep emesis emesis in 30 minutes; keep emesis for analysis for analysis

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Contraindications of ipecac: Contraindications of ipecac:

1.lost gag reflex, decreased level of 1.lost gag reflex, decreased level of consciousness, seizures consciousness, seizures

2. ingestion of agents that rapidly 2. ingestion of agents that rapidly depress mental status (cyclic depress mental status (cyclic antidepressants, hypnotics, antidepressants, hypnotics, strychnine) strychnine)

3. ingestion of caustic agents 3. ingestion of caustic agents

4. petroleum distillate/hydrocarbon 4. petroleum distillate/hydrocarbon ingestion ingestion

5. < 6 months of age5. < 6 months of age

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Gastric lavageGastric lavage

Usually used for extremely toxic Usually used for extremely toxic substances, in cases of unknown substances, in cases of unknown ingestions or when loss of consciousness ingestions or when loss of consciousness is present is present When patient is unable to protect his When patient is unable to protect his

own airway, intubate before own airway, intubate before proceeding proceeding

Warm saline is instilled in aliquots Warm saline is instilled in aliquots until stomach contents are clear. until stomach contents are clear.

Contraindicated: alkalis, sharp objects, pills Contraindicated: alkalis, sharp objects, pills larger than lavage hoselarger than lavage hose

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Activated CharcoalActivated Charcoal Almost irreversibly adsorbs drugs and Almost irreversibly adsorbs drugs and

chemicals, preventing absorption. chemicals, preventing absorption. Consider for all significant toxic Consider for all significant toxic

ingestions; ingestions; poorly binds Fe and Lithium, poorly binds Fe and Lithium, not to be used in caustic ingestions not to be used in caustic ingestions

because of poor binding and makes because of poor binding and makes endoscopy difficult. endoscopy difficult.

Dose = 1 gm/kg or 30-60 gm for children Dose = 1 gm/kg or 30-60 gm for children and 60-100 gm in adults. and 60-100 gm in adults.

Prepared as a slurry with a ratio 1:4 Prepared as a slurry with a ratio 1:4 charcoal to water. Goal is to have a charcoal to water. Goal is to have a charcoal to toxin ratio > 10:1 . charcoal to toxin ratio > 10:1 .

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Activated Charcoal Activated Charcoal (cont.)(cont.) Repetitive doses of charcoal (1 gm/kg q Repetitive doses of charcoal (1 gm/kg q

4-6°) will help clear enterohepatic 4-6°) will help clear enterohepatic circulation of some drugs circulation of some drugs (carbamazepine, digoxin, phenobarb, (carbamazepine, digoxin, phenobarb, salicylates, theophylline).salicylates, theophylline).

Cathartics such as sorbitol (5 ml/kg) Cathartics such as sorbitol (5 ml/kg) can be used with first dose of charcoal can be used with first dose of charcoal to prevent constipation. to prevent constipation.

Cathartics should not be used Cathartics should not be used repetitively as it will cause fluid and repetitively as it will cause fluid and electrolyte disturbances.electrolyte disturbances.

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Enhanced elimination of the Absorbed Enhanced elimination of the Absorbed SubstanceSubstance Forced diuresis (falling out of favor) Forced diuresis (falling out of favor) AlkalinizationAlkalinization

Ingestions of phenobarbital, Ingestions of phenobarbital, salicylate. salicylate.

0.5-2 mEg/kg/hour IV NaHCO3 - 0.5-2 mEg/kg/hour IV NaHCO3 - titrate to keep urine pH 7.5-8.0titrate to keep urine pH 7.5-8.0..

AcidificationAcidification Used for ingestions of amphetamine, Used for ingestions of amphetamine,

chloroquine, lidocaine, quinidine chloroquine, lidocaine, quinidine Ammonium chloride 75 mg/kg/day Ammonium chloride 75 mg/kg/day

(contraindication: hepatic (contraindication: hepatic insufficiency) insufficiency)

Keep urine pH 5.5 -6.0Keep urine pH 5.5 -6.0

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Haemodialysis and hemoperfusion: Haemodialysis and hemoperfusion:

Dialysis has been used for many Dialysis has been used for many substances, substances, somesome of which are: ammonia, of which are: ammonia, amphetamines, anilines, antibiotics, amphetamines, anilines, antibiotics, barbiturates, boric acid, bromides, barbiturates, boric acid, bromides, calcium, chloral hydrate, ethylene glycol, calcium, chloral hydrate, ethylene glycol, fluorides, iodides, isoniazid, fluorides, iodides, isoniazid, meprobamate, methanol, paraldehyde, meprobamate, methanol, paraldehyde, potassium, quinidine, quinine, salicylates, potassium, quinidine, quinine, salicylates, strychnine, thiocyanatesstrychnine, thiocyanates

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AntidotesAntidotes

Use of specific antidotes is Use of specific antidotes is invaluable; unfortunately few invaluable; unfortunately few poisons have antidotes poisons have antidotes

SUMMARY OF ANTIDOTESSUMMARY OF ANTIDOTES

##Acetaminophen Acetaminophen ▬►▬►N-N-AcetylcysteineAcetylcysteine Initial dose of Initial dose of 140 mg/kg PO in water, cola, juice 140 mg/kg PO in water, cola, juice or soda: then, 70 mg/kg q 4 hr for or soda: then, 70 mg/kg q 4 hr for 68 hrs (17 doses, 18 total doses). 68 hrs (17 doses, 18 total doses).

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AnticholinergicsAnticholinergics▬►▬►PhysostigminPhysostigminee ( (CAUTION:CAUTION: may cause seizures, may cause seizures, asystole, cholinergic crisis)asystole, cholinergic crisis)

Anticholinesterases Anticholinesterases ▬►▬►AtropineAtropine IM or IVIM or IV

Organophosphates Organophosphates ▬►▬►Pralidoxime + atropinePralidoxime + atropine

Carbamates Carbamates ▬►▬►Atropine; Atropine; pralidoxime for severe casespralidoxime for severe cases

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Benzodiazepines Benzodiazepines ▬►▬►FlumazenilFlumazenil 0.01 mg/kg IV, 0.01 mg/kg IV, max. dose 3 mg (estimated max. dose 3 mg (estimated pediatric dose)pediatric dose)

Beta-adrenergic blockers Beta-adrenergic blockers ▬►▬►GlucagonGlucagon

Calcium channel blockers Calcium channel blockers ▬►▬► Calcium chloride 10%, or Calcium chloride 10%, or Calcium gluconate 10Calcium gluconate 10%%

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Carbon monoxide Carbon monoxide ▬►▬►Oxygen Oxygen 100% inhalation, consider 100% inhalation, consider hyperbaric for severe caseshyperbaric for severe cases

Cyanide Cyanide ▬► Cyanide antidotal kit▬► Cyanide antidotal kit Adult: 1. Adult: 1. Amyl nitrate inhalationAmyl nitrate inhalation

(inhale for 15-30 sec every 60 sec) (inhale for 15-30 sec every 60 sec) 2. 2. Sodium nitriteSodium nitrite (10 ml of a (10 ml of a

3% solution) IV slowly over 2-4 min.3% solution) IV slowly over 2-4 min. 3. Follow immediately with 3. Follow immediately with

sodium thiosulfatesodium thiosulfate (2.5-5 ml/min of (2.5-5 ml/min of 25 % solution) IV25 % solution) IV

Children: Na nitrite should not exceed Children: Na nitrite should not exceed recommended dose because fatal recommended dose because fatal methemoglobinemiamethemoglobinemia may result may result

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Ethylene glycol Ethylene glycol ▬►▬►(similar to (similar to methanol)methanol)

Fluoride Fluoride ▬►▬►Calcium Calcium gluconate 10%, IV slowlygluconate 10%, IV slowly

Digitalis Digitalis ▬►▬►Fab antibodies Fab antibodies (Digibind) (Digibind)

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Heavy metals:Heavy metals:

Heavy metals/usual chelatorsHeavy metals/usual chelators Arsenic Arsenic ▬►▬►BAL (dimercaprol), IM BAL (dimercaprol), IM

for up to 7 daysfor up to 7 days Lead Lead ▬►▬►BAL, EDTA (IM or slow BAL, EDTA (IM or slow

IV ), (± penicillamine, PO in IV ), (± penicillamine, PO in divided doses for up to 5 days), divided doses for up to 5 days), DMSA (succimer)DMSA (succimer)

Mercury Mercury ▬►▬►BAL, DMSA (PO every BAL, DMSA (PO every 8 hours for 5 days )8 hours for 5 days )

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Iron Iron ▬►▬►DeferoxamineIVDeferoxamineIV Isoniazid Isoniazid ▬►▬►Pyridoxine 5-10%, Pyridoxine 5-10%,

IV slowly.IV slowly. Methanol and Ethylene Glycol Methanol and Ethylene Glycol

▬►▬►EthanolEthanol ALSO: ALSO:- Folate 50 -100 mg IV every 6 - Folate 50 -100 mg IV every 6 hours (methanol)hours (methanol)

- Thiamine 0.5 mg/kg and - Thiamine 0.5 mg/kg and pyridoxine 2 mg/kg for ethylene pyridoxine 2 mg/kg for ethylene glycolglycol

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Methemoglobinemia Methemoglobinemia ▬►▬►Methylene Methylene blue 1%, 1-2 mg/kg (0.1-0.2 ml/kg) blue 1%, 1-2 mg/kg (0.1-0.2 ml/kg) IV slowly IV slowly

Opioids Opioids ▬►▬►Naloxone 0.1 mg/kg IV, Naloxone 0.1 mg/kg IV,

IMIM

Warfarin (and superwarfarin rat Warfarin (and superwarfarin rat poisons) poisons) ▬►▬►Vitamin KVitamin K