1. 1 Management of poisoning All poisoned patients should be treated as if they have a potentially life-threatening intoxication. All poisoned patients should be treated as if they have a potentially life-threatening intoxication. Treat the patient and not the poison. Treat the patient and not the poison.

2. 2 Emergency evaluation ABC supportive therapy:- ABC supportive therapy:- A = Airway Clear A = Airway Clear B = Breathing Maintain B = Breathing Maintain C = Circulation Assist C = Circulation Assist Altered mental status Depression or Excitation Altered mental status Depression or Excitation Fever (hyperthermia) or Hypothermia Fever (hyperthermia) or Hypothermia

3. 3 Emergency evaluation (cont.) Other complications: e.g. Rhabdomyolysis Other complications: e.g. Rhabdomyolysis Clinical diagnosis: Clinical diagnosis: - Physical examination - Physical examination - Essential lab tests - Essential lab tests Decontamination-----To reduce absorption Decontamination-----To reduce absorption Enhanced elimination----Antidote, dialysis. Enhanced elimination----Antidote, dialysis.

4. 4 Airway Loss of airway protective reflexes Loss of airway protective reflexes Airway obstruction by flaccid tongue, aspiration of gastric contents, or respiratory arrest Airway obstruction by flaccid tongue, aspiration of gastric contents, or respiratory arrest Death Death - If reflexes were lost----do endotracheal intubation

5. 5 Endotracheal intubation Not easy--------requires expertise Not easy--------requires expertise Nasotracheal intubaion: Nasotracheal intubaion: - requires local anaesthetic( lidocaine) ----reduces pain + vasoconstrictor (phenylephrine) ---- reduces bleeding - requires local anaesthetic( lidocaine) ----reduces pain + vasoconstrictor (phenylephrine) ---- reduces bleeding Orotracheal intubation: Orotracheal intubation: - requires oxygen - requires oxygen - requires neuromuscular blocker e.g. suxamethonium ( in children suxamethonium induces bradycardia or asystole, so pancuronium is recommended in children) - requires neuromuscular blocker e.g. suxamethonium ( in children suxamethonium induces bradycardia or asystole, so pancuronium is recommended in children)

6. 6 BREATHING Breathing difficulties: major cause of morbidity and death. Breathing difficulties: major cause of morbidity and death. Complications: 1. Ventilatory failure Complications: 1. Ventilatory failure 2. Hypoxia 2. Hypoxia 3. Bronchospasm 3. Bronchospasm

7. 7 1. Ventilatory failure Differential diagnosis Differentiate poisoning from bacterial or viral diseases. Differentiate poisoning from bacterial or viral diseases. 1. May result in brain damage, cardiac arrhythmias, and cardiac arrest. 1. May result in brain damage, cardiac arrhythmias, and cardiac arrest. 2. Hypercarbia results in acidosis, which may contribute to arrhythmias, especially in patients with cyclic antidepressant overdose. 2. Hypercarbia results in acidosis, which may contribute to arrhythmias, especially in patients with cyclic antidepressant overdose.

8. 8 CAUSES OF VENTILATORY FAILURE: a) Failure of respiratory muscles e.g, by a) Failure of respiratory muscles e.g, by - Neuromuscular blockers - Organophosphates and carbamates - Botulinum toxin - Neuromuscular blockers - Organophosphates and carbamates - Botulinum toxin - Snake bite - Snake bite b) Depression of respiratory center e.g. by barbiturates, alcohols, opioids b) Depression of respiratory center e.g. by barbiturates, alcohols, opioids c) Severe pneumonia. c) Severe pneumonia. d) Pulmonary oedema d) Pulmonary oedema

9. 9 Treatment 1. Assist breathing manually with a bag- valve-mask device 1. Assist breathing manually with a bag- valve-mask device 2. Perform endotracheal intubation 2. Perform endotracheal intubation 3.Use oxygen (usually 30—35% to start). 3.Use oxygen (usually 30—35% to start).

10. 10 2. Hypoxia Differential diagnosis Differential diagnosis Differentiate from pneumonia. Differentiate from pneumonia.

11. 11 CAUSES OF HYPOXIA 1.Insufficient oxygen in air (e.g. displacement of oxygen by inert gases). 1.Insufficient oxygen in air (e.g. displacement of oxygen by inert gases). 2.Disruption of oxygen absorption by the lung (e.g. resulting from pneumonia or pulmonary edema). 2.Disruption of oxygen absorption by the lung (e.g. resulting from pneumonia or pulmonary edema). 3. Cellular hypoxia 3. Cellular hypoxia

12. 12 CAUSES OF HYPOXIA (cont.) a.Pneumonia. The most common cause of pneumonia in overdosed patients is pulmonary aspiration of gastric contents. a.Pneumonia. The most common cause of pneumonia in overdosed patients is pulmonary aspiration of gastric contents. Pneumonia may also be caused by intravenous injection of foreign material or bacteria, aspiration of petroleum distillates or inhalation of irritant gases. Pneumonia may also be caused by intravenous injection of foreign material or bacteria, aspiration of petroleum distillates or inhalation of irritant gases.

13. 13 CAUSES OF HYPOXIA (cont.) b. Pulmonary edema: b. Pulmonary edema: - Cardiogenic pulmonary edema caused by Beta blockers, Cyclic antidepressants, Quinidine - Cardiogenic pulmonary edema caused by Beta blockers, Cyclic antidepressants, Quinidine - Non-cardiogenic pulmonary edema caused by aspiration of hydrocarbons (e.g. petroleum) - Non-cardiogenic pulmonary edema caused by aspiration of hydrocarbons (e.g. petroleum)

14. 14 CAUSES OF HYPOXIA (cont.) 3. Cellular hypoxia: e.g. by carbon monoxide or methemoglobinemia, which limit binding of oxygen to hemoglobin, and cyanide, which blocks oxygen utilization. 3. Cellular hypoxia: e.g. by carbon monoxide or methemoglobinemia, which limit binding of oxygen to hemoglobin, and cyanide, which blocks oxygen utilization.

15. 15 Treatment Correct hypoxia e.g.: Correct hypoxia e.g.: - Administer 100% oxygen in carbon monoxide poisoning - Administer 100% oxygen in carbon monoxide poisoning - Give cyanide antidote kit for cyanide - Give cyanide antidote kit for cyanide

16. 16 3. Bronchospasm Differentiate from asthma, hypersensitivity or allergic reactions. Differentiate from asthma, hypersensitivity or allergic reactions. Severe bronchospasm may result in hypoxia and ventilatory failure. Severe bronchospasm may result in hypoxia and ventilatory failure.

17. 17 Examples of drugs and toxins that cause bronchospasm 1.Direct irritant injury from inhaled gases or pulmonary aspiration of petroleum distillates or stomach contents. 1.Direct irritant injury from inhaled gases or pulmonary aspiration of petroleum distillates or stomach contents. 2.Pharmacologic effects of toxins, e.g. organophosphate or carbamate insecticides or beta-adrenergic blockers. 2.Pharmacologic effects of toxins, e.g. organophosphate or carbamate insecticides or beta-adrenergic blockers. 3. Hypersensitivity or allergic reactions may also cause bronchospasm. 3. Hypersensitivity or allergic reactions may also cause bronchospasm.

18. 18 Treatment Treatment 1.Administer supplemental oxygen. 1.Administer supplemental oxygen. 2.Remove the patient from the source of exposure to any irritant gas. 2.Remove the patient from the source of exposure to any irritant gas. 3.Administer bronchodilators: 3.Administer bronchodilators: a.salbutamol inhaler a.salbutamol inhaler b.If this is not effective, give aminophylline, 6 mg/kg IV over 30 minutes. b.If this is not effective, give aminophylline, 6 mg/kg IV over 30 minutes. For patients with bronchospasm and bronchorrhea caused by organophosphate or other anticholinesterase poisoning, give atropine. For patients with bronchospasm and bronchorrhea caused by organophosphate or other anticholinesterase poisoning, give atropine.

19. 19 CIRCULATION I.General assessment and initial treatment I.General assessment and initial treatment A.Check blood pressure and pulse rate and rhythm. Perform cardiopulmonary resuscitation (CPR) if there is no pulse. A.Check blood pressure and pulse rate and rhythm. Perform cardiopulmonary resuscitation (CPR) if there is no pulse. B.Begin continuous electrocardiographic (ECG) monitoring of arrhythmias B.Begin continuous electrocardiographic (ECG) monitoring of arrhythmias (may complicate a variety of drug overdoses). (may complicate a variety of drug overdoses).

20. 20 General assessment (cont.) C.Secure venous access. C.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, hypotensive, obtunded, convulsing, or comatose), place a Foley catheter in the bladder, obtain urine for routine and toxicologic testing, and measure hourly urine output. D. In seriously ill patients (eg, hypotensive, obtunded, convulsing, or comatose), place a Foley catheter in the bladder, obtain urine for routine and toxicologic testing, and measure hourly urine output.

21. 21 2. Bradycardia and atrioventricular (AV) block Examples of drugs and toxins causing bradycardia or AV block Examples of drugs and toxins causing bradycardia or AV block 1.Membrane-depressant drugs (eg, cyclic antidepressants, quinidine, beta blockers) 1.Membrane-depressant drugs (eg, cyclic antidepressants, quinidine, beta blockers) Cholinergic or vagotonic agents - Carbamate insecticides - Digitalis glycosides - Organophosphates Cholinergic or vagotonic agents - Carbamate insecticides - Digitalis glycosides - Organophosphates

22. 22 Examples of drugs and toxins causing bradycardia or AV block (cont.) Sympatholytic agents - Beta blockers - Clonidine Sympatholytic agents - Beta blockers - Clonidine Other - Opiates Other - Opiates - Calcium antagonists - Lithium - Calcium antagonists - Lithium

23. 23 Complications: Bradycardia and AV block frequently cause hypotension, which may progress to asystolic cardiac arrest. Bradycardia and AV block frequently cause hypotension, which may progress to asystolic cardiac arrest.

24. 24 Treatment: Do not treat bradycardia or AV block unless the patient is symptomatic (eg, syncope, hypotension). Do not treat bradycardia or AV block unless the patient is symptomatic (eg, syncope, hypotension). Note: Bradycardia or even AV block may be a protective reflex to lower the blood pressure in a patient with life-threatening hypertension. Note: Bradycardia or even AV block may be a protective reflex to lower the blood pressure in a patient with life-threatening hypertension.

25. 25 Treatment (cont.) 1.Maintain airway and assist breathing. Administer supplemental oxygen. 1.Maintain airway and assist breathing. Administer supplemental oxygen. 2.Rewarm hypothermic patients. 2.Rewarm hypothermic patients. 3.Administer atropine. If this is not successful, use isoprenaline or an emergency pacemaker. 3.Administer atropine. If this is not successful, use isoprenaline or an emergency pacemaker.

26. 26 Treatment (cont.) 4.Use the following specific antidotes if appropriate: 4.Use the following specific antidotes if appropriate: a.For beta-blocker overdose, give glucagon. a.For beta-blocker overdose, give glucagon. b.For digitalis intoxication, use Fab fragments. b.For digitalis intoxication, use Fab fragments. c.For cyclic antidepressant overdose, administer sodium bicarbonate. c.For cyclic antidepressant overdose, administer sodium bicarbonate. d.For calcium antagonist overdose, give calcium. d.For calcium antagonist overdose, give calcium.

27. 27 3. Tachycardia Examples of drugs and toxins causing tachycardia Sympathomimetic agents Amphetamines Sympathomimetic agents Amphetamines Caffeine Cocaine Agents causing cellular hypoxia Carbon monoxide Cyanide Oxidizing agents (methemoglobinemia) Caffeine Cocaine Agents causing cellular hypoxia Carbon monoxide Cyanide Oxidizing agents (methemoglobinemia) Anticholinergic agents Antihistamines Atropine Cyclic antidepressants Phenothiazines Other Ethanol or sedative- hypnotic drug withdrawal Thyroid hormone

28. 28 Treatment If tachycardia is not associated with hypotension If tachycardia is not associated with hypotension For sympathomimetic-induced tachycardia, give propranolol, or esmolol, For sympathomimetic-induced tachycardia, give propranolol, or esmolol, For anticholinergic-induced tachycardia, give physostigmine, or neostigmine. For anticholinergic-induced tachycardia, give physostigmine, or neostigmine. Caution: Do not use these drugs in patients with cyclic antidepressant overdose, because additive depression of conduction may result in asystole. Caution: Do not use these drugs in patients with cyclic antidepressant overdose, because additive depression of conduction may result in asystole.

29. 29 4.Hypotension Complications Severe or prolonged hypotension can cause acute renal tubular necrosis, brain damage, and cardiac ischemia. Severe or prolonged hypotension can cause acute renal tubular necrosis, brain damage, and cardiac ischemia. Metabolic acidosis is a common finding. Metabolic acidosis is a common finding.

30. 30 SELECTED DRUGS AND TOXINS CAUSING HYPOTENSION HYPOTENSION WITH RELATIVE BRADYCARDIA Sympatholytic agents Sympatholytic agents - Beta blockers - Beta blockers - Hypothermia - Hypothermia Membrane-depressant drugs Membrane-depressant drugs - Beta blockers (mainly propranolol) - Beta blockers (mainly propranolol) - Cyclic antidepressants - Cyclic antidepressants Others - Barbiturates - Calcium antagonists - Cyanide - Opiates - Organophosphates and carbamates - Sedative-hypnotic agents

31. 31 HYPOTENSION WITH TACHYCARDIA Arsenic Arsenic Hyperthermia Hyperthermia Caffeine Caffeine Theophylline Theophylline Salbutamol Salbutamol

32. 32 Treatment Fortunately, hypotension usually responds readily to empirical therapy with intravenous fluids and low doses of presser drugs (eg, dopamine). Fortunately, hypotension usually responds readily to empirical therapy with intravenous fluids and low doses of presser drugs (eg, dopamine). 1.Maintain the airway and assist ventilation if necessary. Administer supplemental oxygen. 1.Maintain the airway and assist ventilation if necessary. Administer supplemental oxygen. Administer norepinephrine. Administer norepinephrine.

33. 33 Treatment (cont.) 2.Treat cardiac arrhythmias that may contribute to hypotension (heart rate 180—200/mm. 2.Treat cardiac arrhythmias that may contribute to hypotension (heart rate 180—200/mm. 3. Hypotension associated with hypothermia often will not improve with routine fluid therapy but will rapidly normalize upon rewarming of the patient. 3. Hypotension associated with hypothermia often will not improve with routine fluid therapy but will rapidly normalize upon rewarming of the patient.

34. 34 Treatment (cont.) 4.Consider specific antidotes: 4.Consider specific antidotes: a. Sodium bicarbonate for cyclic antidepressant a. Sodium bicarbonate for cyclic antidepressant b. Glucagon for beta-blocker overdose. b. Glucagon for beta-blocker overdose. c. Calcium for calcium antagonist overdose. c. Calcium for calcium antagonist overdose. d. If the systemic vascular resistance is low, administer norepinephrine d. If the systemic vascular resistance is low, administer norepinephrine

35. 35 5. Hypertension Complications: Complications: Severe hypertension can result in intracranial hemorrhage, aortic dissection, myocardial infarction, and congestive heart failure. Severe hypertension can result in intracranial hemorrhage, aortic dissection, myocardial infarction, and congestive heart failure.

36. 36 SELECTED DRUGS AND TOXINS CAUSING HYPERTENSION HYPERTENSION WITH TACHYCARDIA HYPERTENSION WITH TACHYCARDIA Generalized sympathomimetic agents Anticholinerglc agents Amphetamines and derivatives Antihistamines Cocaine Atropine Cyclic antidepressants Epinephrine Phenothiazines Generalized sympathomimetic agents Anticholinerglc agents Amphetamines and derivatives Antihistamines Cocaine Atropine Cyclic antidepressants Epinephrine Phenothiazines Levodopa Other LSD (lysergic acid diethylamide) Ethanol and sedative-hypnotic Levodopa Other LSD (lysergic acid diethylamide) Ethanol and sedative-hypnotic drug withdrawal Marihuana Nicotine (early stage) Monoamine oxidase inhibitors Organophosphates Phencyclidine drug withdrawal Marihuana Nicotine (early stage) Monoamine oxidase inhibitors Organophosphates Phencyclidine

37. 37 SELECTED DRUGS AND TOXINS CAUSING HYPERTENSION (cont.) HYPERTENSION WITH BRADYCARDIA OR ATRIOVENTRICULAR BLOCK HYPERTENSION WITH BRADYCARDIA OR ATRIOVENTRICULAR BLOCK Clonidine Norepinephrine Ergot derivatives Phenylephrine Phenylpropanolamine

38. 38 Treatment Rapid lowering of the blood pressure is desirable. Rapid lowering of the blood pressure is desirable. For hypertension with little or no tachycardia, use phentolamine, nifedipine chewable capsule or liquid form,or nitroprusside. For hypertension with little or no tachycardia, use phentolamine, nifedipine chewable capsule or liquid form,or nitroprusside. For hypertension with tachycardia, add to the above treatment propranolol, or esmolol, or labetalol. For hypertension with tachycardia, add to the above treatment propranolol, or esmolol, or labetalol. Caution: Do not use propranolol or esmolol alone to treat hypertensive crisis; beta blockers may paradoxically worsen hypertension if it is caused primarily by alpha stimulation. Caution: Do not use propranolol or esmolol alone to treat hypertensive crisis; beta blockers may paradoxically worsen hypertension if it is caused primarily by alpha stimulation.

39. 39 ALTERED MENTAL STATUS l. COMA AND STUPOR l. COMA AND STUPOR a) Causes: a) Causes: - Drugs and toxins that depress brain reticular activating system(RAS) - After seizures - Brain injury associated with infarction or intracranial bleeding.

40. 40 b) Complications: Respiratory depression (cause of death) Respiratory depression (cause of death) Hypotension, hypothermia, hyperthermia and rhabdomyolysis Hypotension, hypothermia, hyperthermia and rhabdomyolysis

41. 41 c) Treatment: -AB supportive + Oxygen -AB supportive + Oxygen -50% dextrose + thiamine( thiamine prevents Wernicke’s syndrome in persons deficient in thiamine) -50% dextrose + thiamine( thiamine prevents Wernicke’s syndrome in persons deficient in thiamine) Normalize body temperature Normalize body temperature Naloxone is routinely given in respiratory depression (may ppt. opioid withdrawal) Naloxone is routinely given in respiratory depression (may ppt. opioid withdrawal) Flumazenil may be considered Flumazenil may be considered

42. 42 ll. Hypothermia: Serious when temp. < 32 °C (90 °F ) Serious when temp. < 32 °C (90 °F )Treatment: - + O 2 - AB supportive + O 2 - Rewarm slowly (to avoid rewarming arrhythmia) ( this arrhythmia does not respond to the usual treatment of v. arrhythmia – bretylium may be effective)

43. 43 Open cardiac massage with direct warm irrigation of ventricles may be needed in hypothermic patients in cardiac arrest. Open cardiac massage with direct warm irrigation of ventricles may be needed in hypothermic patients in cardiac arrest.

44. 44 lll. Hyperthermia Serious when temp. > 40 °C (104 °F) Serious when temp. > 40 °C (104 °F) A) Causes A) Causes 1. Drugs and toxins: - antipsychotics(chronic use)▬► neuroleptic malignant syndrome - halothane and suxamethonium▬►malignant hyperthermia (inherited disorder) - amphetamines and cocaine▬► excessive muscular activity

45. 45 - aspirin (toxic doses)▬► uncoupling of oxidative phosphorylation - serotonergic drugs e.g. fluoxetine ▬► serotonin syndrome - withdrawal from alcohol and sedative hypnotics 2. Other causes: heat stroke, infections, meningitis, thyrotoxicosis……… etc. heat stroke, infections, meningitis, thyrotoxicosis……… etc.

46. 46 B. Complications: Rhabdomyolsis Rhabdomyolsis Renal failure Renal failure Cardiac failure Cardiac failure Brain damage Brain damage Death Death

47. 47 C. Treatment: Immediate rapid cooling Immediate rapid cooling - AB supportive + oxygen - AB supportive + oxygen - I.V. glucose - I.V. glucose - control seizures, agitation or muscular rigidity - control seizures, agitation or muscular rigidity - continue cooling with tepid sponging, fanning, - continue cooling with tepid sponging, fanning, or iced gastric or colonic lavage, or iced gastric or colonic lavage, or ice water immersion or ice water immersion

48. 48 Treatment (cont.): - To prevent shivering give: diazepam or midazolam( central muscle relaxants) diazepam or midazolam( central muscle relaxants) or neuromuscular blockers (pancuronium) or neuromuscular blockers (pancuronium) - For persistent hyperthermia use: dantrolene (peripherally, prevents calcium release from sarcoplasmic reticulum of skeletal muscle dantrolene (peripherally, prevents calcium release from sarcoplasmic reticulum of skeletal muscle

49. 49 Treatment (cont.): - For neuroleptic malignant syndrome use: bromocriptine (dopamine agonist) bromocriptine (dopamine agonist) - for serotonin syndrome use: methysergide (serotonin antagonist) methysergide (serotonin antagonist)

50. 50 lV. Seizures A) Causative drugs and toxins: - amphetamines and cocaine - amphetamines and cocaine - propranolol (but not atenolol) - propranolol (but not atenolol) - camphor - camphor - organophosphates - organophosphates - CO or cyanide (cellular hypoxia) - CO or cyanide (cellular hypoxia) - tricyclics - tricyclics - haloperidol - lead and other heavy metals - methanol - salicylates -withdrawal from ethanol or sedatives

51. 51 b) Complications: -apnoea -pulmonary aspiration -hyperthermia-rhabdomyolysis -brain damage

52. 52 C) Treatment: 1. AB supportive + oxygen 2. Naloxone 3. If hypoglycemic, give 50% glucose + thiamine 4. Use anticonvulsants e.g. diazepam, phenytoin, phenobarbitone diazepam, phenytoin, phenobarbitone Anticonvulsants shoud be administered slowly ( if given rapidly, can cause hypotension, cardiac arrest or respiratory arrest) Anticonvulsants shoud be administered slowly ( if given rapidly, can cause hypotension, cardiac arrest or respiratory arrest)

53. 53 Treatment (cont.): - If hyperthermic: cooling; pancuronium - Use specific antidotes if possible e.g. pralidoxime + atropine for organophosphates

54. 54 V. Agitation, delirium and psychosis Agitation = continuous and excessive restlessness Delirium = a state of mental confusion and excitement Psychosis = delusions (false beliefs) + hallucinations (false sensation) + indifference + excitement

55. 55 a) Causative drugs and toxins: - Lead and other heavy metals - Carbon monoxide - L-dopa - Salicylates - Withdrawal from ethanol or sedatives - Amphetamines and cocaine - L.S.D. and marihuana

56. 56 b) Complications: - Hyperthermia - Rhabdomyolysis C) Treatment: - Rapid cooling, if hyperthermic - Treat hypoglycemia - Give a sedative ( midazolam or diazepam) or a an antipsychotic (haloperidol) - Administer pancuronium (intubation may be needed)

57. 57 Diagnosis of poisoning Correct diagnosis is through data from history, physical examination and lab. tests. Correct diagnosis is through data from history, physical examination and lab. tests. 1. History 1. History - Collect history of ingestion from the patient, family, friends pharmacy…….etc. - Collect history of ingestion from the patient, family, friends pharmacy…….etc. - Collect any drugs or drug remnants for later testing - Collect any drugs or drug remnants for later testing ( Rescuer should avoid skin contact or needle stick). ( Rescuer should avoid skin contact or needle stick).

58. 58 Diagnosis of poisoning (cont.) 2. Physical examination: Look for general signs that may lead to the poison (B.P., pulse, eye, skin, ….etc.) Look for general signs that may lead to the poison (B.P., pulse, eye, skin, ….etc.) ♠ α-adrenergic syndrome (e.g. with phenylpropanolamines) B.P. + reflex bradycardia + dilated pupil B.P. + reflex bradycardia + dilated pupil

59. 59 ♠ β -adrenergic syndrome (e.g. with salbutamol) B.P. (β 2 vasodilatation) + tachycardia B.P. (β 2 vasodilatation) + tachycardia

60. 60 ♠ Mixed α – and β adrenergic syndrome (e.g. amphetamines and cocaine ) (e.g. amphetamines and cocaine ) B.P + tachycardia + dilated pupil B.P + tachycardia + dilated pupil ♠ Sympatholytic syndrome ( e.g. Clonidine, methyldopa, also opioids ) B.P + bradycardia + pin-point pupil B.P + bradycardia + pin-point pupil

61. 61 ♠ Nicotinic cholinergic syndrome (autonomic ganglia) (autonomic ganglia) e.g. nicotine e.g. nicotine - Initial tachycardia followed by bradycardia - Initial tachycardia followed by bradycardia - Muscle fasciculation followed by paralysis - Muscle fasciculation followed by paralysis ♠ Muscarinic cholinergic syndrome : (muscarine) (muscarine) bradycardia + miosis + sweating + SLUD bradycardia + miosis + sweating + SLUD

62. 62 ♠ 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 : (e.g. atropine, cyclic antidepressants, antihistamines) (e.g. atropine, cyclic antidepressants, antihistamines) - Tachycardia - Tachycardia - Hot dry skin - Hot dry skin - Urinary retention - Urinary retention

63. 63 Characteristic odours: Examples: Examples: Acetone acetone, chloroform Acetone acetone, chloroform Bitter almond cyanide Bitter almond cyanide Garlic arsenic, organophosphates Garlic arsenic, organophosphates

64. 64 Essential clinical lab tests Routine tests: Routine tests: 1. Serum osmolality: Measure Na, glucose and BUN serum concentration. Measure Na, glucose and BUN serum concentration. 1- Calculate osmolality (calculated osmolality) = 2[Na] + [glucose] / 18 + [BUN] / 2.8 1- Calculate osmolality (calculated osmolality) = 2[Na] + [glucose] / 18 + [BUN] / 2.8 (Normal osmolality (Normal osmolality value = 290 mosmol / L) 2- Measure serum osmolality by an Osmometer (measured osmolality ) 2- Measure serum osmolality by an Osmometer (measured osmolality ) 3- Osmolar gap = measured osmolality – calculated osmolality 3- Osmolar gap = measured osmolality – calculated osmolality Increased osmolar gap is seen with alcohol or ethylene glycol poisoning

65. 65 2. Anion gap: Measure Na, chloride and bicarbonate serum concentration. Measure Na, chloride and bicarbonate serum concentration. Calculate anion gap: Calculate anion gap: anion gap = [Na + ] - [CL - ] - [HCO 3 -] anion gap = [Na + ] - [CL - ] - [HCO 3 -] Normal anion gap Normal anion gap value = 6-12 meq / L Increased anion gap is seen with alcohol, ethylene glycol, CO, cyanide poisoning

66. 66 Other tests: 3. Measurement of serum potassium 3. Measurement of serum potassium 4. Renal function tests: 4. Renal function tests: - measure serum creatinine and BUN levels - measure serum creatinine and BUN levels 5. Liver function tests: 5. Liver function tests: - measure liver transaminases levels - measure liver transaminases levels

67. 67 Elimination of the poison from the GI tract, skin and eyes A. Gastric emptying A. Gastric emptying Syrup of Ipecac - usually used at home, rarely used after presenting to medical facility. Syrup of Ipecac - usually used at home, rarely used after presenting to medical facility. Dose: 12 years = 30 ml Dose: 12 years = 30 ml Follow with water or juice (induction of emesis will be delayed if given with milk); repeat once if no emesis in 30 minutes; keep emesis for analysis Follow with water or juice (induction of emesis will be delayed if given with milk); repeat once if no emesis in 30 minutes; keep emesis for analysis

68. 68 Contraindications of ipecac: 1.lost gag reflex, decreased level of consciousness, seizures 2. ingestion of agents that rapidly depress mental status (cyclic antidepressants, hypnotics, strychnine) 3. ingestion of caustic agents 4. petroleum distillate/hydrocarbon ingestion 5. < 6 months of age

69. 69 Gastric lavage Usually used for extremely toxic substances, in cases of unknown ingestions or when loss of consciousness is present Usually used for extremely toxic substances, in cases of unknown ingestions or when loss of consciousness is present When patient is unable to protect his own airway, intubate before proceeding When patient is unable to protect his own airway, intubate before proceeding Warm saline is instilled in aliquots until stomach contents are clear. Warm saline is instilled in aliquots until stomach contents are clear. Contraindicated: alkalis, sharp objects, pills larger than lavage hose Contraindicated: alkalis, sharp objects, pills larger than lavage hose

70. 70 Activated Charcoal Almost irreversibly adsorbs drugs and chemicals, preventing absorption. Almost irreversibly adsorbs drugs and chemicals, preventing absorption. Consider for all significant toxic ingestions; Consider for all significant toxic ingestions; poorly binds Fe and Lithium, poorly binds Fe and Lithium, not to be used in caustic ingestions because of poor binding and makes endoscopy difficult. not to be used in caustic ingestions because of poor binding and makes endoscopy difficult. Dose = 1 gm/kg or 30-60 gm for children and 60- 100 gm in adults. Dose = 1 gm/kg or 30-60 gm for children and 60- 100 gm in adults. Prepared as a slurry with a ratio 1:4 charcoal to water. Goal is to have a charcoal to toxin ratio > 10:1. Prepared as a slurry with a ratio 1:4 charcoal to water. Goal is to have a charcoal to toxin ratio > 10:1.

71. 71 Activated Charcoal (cont.) Repetitive doses of charcoal (1 gm/kg q 4-6°) will help clear enterohepatic circulation of some drugs (carbamazepine, digoxin, phenobarb, salicylates, theophylline). Repetitive doses of charcoal (1 gm/kg q 4-6°) will help clear enterohepatic circulation of some drugs (carbamazepine, digoxin, phenobarb, salicylates, theophylline). Cathartics such as sorbitol (5 ml/kg) can be used with first dose of charcoal to prevent constipation. Cathartics such as sorbitol (5 ml/kg) can be used with first dose of charcoal to prevent constipation. Cathartics should not be used repetitively as it will cause fluid and electrolyte disturbances. Cathartics should not be used repetitively as it will cause fluid and electrolyte disturbances.

72. 72 Enhanced elimination of the Absorbed Substance Forced diuresis (falling out of favor) Forced diuresis (falling out of favor) Alkalinization Alkalinization Ingestions of phenobarbital, salicylate. Ingestions of phenobarbital, salicylate. 0.5-2 mEg/kg/hour IV NaHCO3 - titrate to keep urine pH 7.5-8.0. 0.5-2 mEg/kg/hour IV NaHCO3 - titrate to keep urine pH 7.5-8.0.Acidification Used for ingestions of amphetamine, chloroquine, lidocaine, quinidine Used for ingestions of amphetamine, chloroquine, lidocaine, quinidine Ammonium chloride 75 mg/kg/day (contraindication: hepatic insufficiency) Ammonium chloride 75 mg/kg/day (contraindication: hepatic insufficiency) Keep urine pH 5.5 -6.0 Keep urine pH 5.5 -6.0

73. 73 Haemodialysis and hemoperfusion: Dialysis has been used for many substances, some of which are: ammonia, amphetamines, anilines, antibiotics, barbiturates, boric acid, bromides, calcium, chloral hydrate, ethylene glycol, fluorides, iodides, isoniazid, meprobamate, methanol, paraldehyde, potassium, quinidine, quinine, salicylates, strychnine, thiocyanates

74. 74 Antidotes Use of specific antidotes is invaluable; unfortunately few poisons have antidotes Use of specific antidotes is invaluable; unfortunately few poisons have antidotes SUMMARY OF ANTIDOTES SUMMARY OF ANTIDOTES # Acetaminophen ▬►N-Acetylcysteine Initial dose of 140 mg/kg PO in water, cola, juice or soda: then, 70 mg/kg q 4 hr for 68 hrs (17 doses, 18 total doses).

75. 75 Anticholinergics▬►Physostigmine (CAUTION: may cause seizures, asystole, cholinergic crisis) Anticholinergics▬►Physostigmine (CAUTION: may cause seizures, asystole, cholinergic crisis) Anticholinesterases ▬►Atropine IM or IV Anticholinesterases ▬►Atropine IM or IV Organophosphates ▬►Pralidoxime + atropine Organophosphates ▬►Pralidoxime + atropine Carbamates ▬►Atropine; pralidoxime for severe cases Carbamates ▬►Atropine; pralidoxime for severe cases

76. 76 Benzodiazepines ▬►Flumazenil 0.01 mg/kg IV, max. dose 3 mg (estimated pediatric dose) Benzodiazepines ▬►Flumazenil 0.01 mg/kg IV, max. dose 3 mg (estimated pediatric dose) Beta-adrenergic blockers ▬►Glucagon Beta-adrenergic blockers ▬►Glucagon Calcium channel blockers ▬► Calcium chloride 10%, or Calcium gluconate 10 % Calcium channel blockers ▬► Calcium chloride 10%, or Calcium gluconate 10 %

77. 77 Carbon monoxide ▬►Oxygen 100% inhalation, consider hyperbaric for severe cases Carbon monoxide ▬►Oxygen 100% inhalation, consider hyperbaric for severe cases Cyanide ▬► Cyanide antidotal kit Cyanide ▬► Cyanide antidotal kit Adult: 1. Amyl nitrate inhalation (inhale for 15- 30 sec every 60 sec) Adult: 1. Amyl nitrate inhalation (inhale for 15- 30 sec every 60 sec) 2. Sodium nitrite (10 ml of a 3% solution) IV slowly over 2-4 min. 2. Sodium nitrite (10 ml of a 3% solution) IV slowly over 2-4 min. 3. Follow immediately with sodium thiosulfate (2.5-5 ml/min of 25 % solution) IV 3. Follow immediately with sodium thiosulfate (2.5-5 ml/min of 25 % solution) IV Children: Na nitrite should not exceed recommended dose because fatal methemoglobinemia may result Children: Na nitrite should not exceed recommended dose because fatal methemoglobinemia may result

78. 78 Ethylene glycol ▬►(similar to methanol) Ethylene glycol ▬►(similar to methanol) Fluoride ▬►Calcium gluconate 10%, IV slowly Fluoride ▬►Calcium gluconate 10%, IV slowly Digitalis ▬►Fab antibodies (Digibind) Digitalis ▬►Fab antibodies (Digibind)

79. 79 Heavy metals: Heavy metals/usual chelators Heavy metals/usual chelators Arsenic ▬►BAL (dimercaprol), IM for up to 7 days Arsenic ▬►BAL (dimercaprol), IM for up to 7 days Lead ▬►BAL, EDTA (IM or slow IV ), (± penicillamine, PO in divided doses for up to 5 days), DMSA (succimer) Lead ▬►BAL, EDTA (IM or slow IV ), (± penicillamine, PO in divided doses for up to 5 days), DMSA (succimer) Mercury ▬►BAL, DMSA (PO every 8 hours for 5 days ) Mercury ▬►BAL, DMSA (PO every 8 hours for 5 days )

80. 80 Iron ▬►DeferoxamineIV Iron ▬►DeferoxamineIV Isoniazid ▬►Pyridoxine 5-10%, IV slowly. Isoniazid ▬►Pyridoxine 5-10%, IV slowly. Methanol and Ethylene Glycol ▬►Ethanol ALSO: - Folate 50 -100 mg IV every 6 hours (methanol) Methanol and Ethylene Glycol ▬►Ethanol ALSO: - Folate 50 -100 mg IV every 6 hours (methanol) - Thiamine 0.5 mg/kg and pyridoxine 2 mg/kg for ethylene glycol - Thiamine 0.5 mg/kg and pyridoxine 2 mg/kg for ethylene glycol

81. 81 Methemoglobinemia ▬►Methylene blue 1%, 1-2 mg/kg (0.1-0.2 ml/kg) IV slowly Methemoglobinemia ▬►Methylene blue 1%, 1-2 mg/kg (0.1-0.2 ml/kg) IV slowly Opioids ▬►Naloxone 0.1 mg/kg IV, IM Opioids ▬►Naloxone 0.1 mg/kg IV, IM Warfarin (and superwarfarin rat poisons) ▬►Vitamin K Warfarin (and superwarfarin rat poisons) ▬►Vitamin K