TOXICOLOGY ?

1. TOXICOLOGY ? CLINICAL TOXICOLOGY ?

2. the science dealing with the toxicityof substances. the science dealing with the toxicity of substances in a person.

3. POISON • A poison is a solid, liquid or gaseous substance, which if introduced in to the living body, or brought in contact with any part produces ill effects or death by its local, systemic or both types of action. • A drug in high doses or a toxic substance are considered as poison.

4. Types of Poisoning • Acute poisoning: In acute poisoning, whatever amount of drug/poison is taken and the toxicity is manifested immediately. • Chronic poisoning: Small amount of drug/ poison are repeatedly administered for a long period producing the toxic effects. Ex. metallic poisons, opium, antimony etc. • Subacute poisoning: poisoning manifests between the acute and the subacute types of toxicity.

5. Factors Modifying the Actions of Poisons • Quantity • Route of administration • Age and state of the body • Tolerance

6. Manner of Poisoning • Homicidal poisoning • Suicidal poisoning • Accidental poisoning

7. CLASSIFICATION OF POISONS

8. General principles in the treatment of poisoning

9. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

10. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

11. 1. Stabilization • The initial survey should always be directed at the assessment and correction of life-threatening problems. • Attention must be paid to the airway, breathing, circulation, and depression of the CNS (the ABCD of resuscitation).

12. 1.1 Airway and breathing Signs & Symptoms of airway obstruction includes • Dyspnoea • Air hunger • Hoarseness • Cyanosis • Sweating • Tachypnoea • Measuring blood gases. Ventilation is required if • PaCO2 > 45 mmHg • PaO2 <70 mm Hg

13. Drugs which causes respiratory depression

15. Management of respiratory insufficiency

16. 1.2. Circulation

17. 1.2. Circulation

18. Management of circulatory failure • Elevate foot end of the bed • Insert a large peripheral IV line and administer 200ml of saline. Observe for improvement in BP over 10 min. • If fails, repeat IV bolus of saline upto 2 litres. • If fails, then vasopressors such as dopamine 1-5 µg/kg/min or noradrenaline 0.5 – 1 ml/min.

19. Management of cardiac arrythmias • Obtain an ECG • Evaluate for hypoxia, acidosis and electrolyte disturbances (hypokalemia, hypocalcaemia and hypomagnesaemia). • Lignocaine – 1.5 mg/kg iv and • amiodarone – 4 mg/min first line drugs • Atropine – used in severe bradycardia

20. 1.3. Depression

21. Management of depression

22. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

23. 2. Evaluation • Hypothermia • Hyperthermia • Acid-base disorders • Convulsions • Agitation • Electrolyte disturbances (Hyperkalemia, Hypokalemia, • Hypernatremia, Hyponatremia, Hypocalcemia)

24. 2.1 Hypothermia Treatment: Rewarming with warm water, Heating the inspired air, gastric lavage with warm fluids

25. 2.2 Hyperthermia

27. 2.3 Acid-base disorders • Diagnosed based on arterial blood gases, pH, bicarbonate and serum electrolytes. • Sodium bicarbonate is the best antidote for acidosis. • Alkalosis – Dextrose solution is preferred.

28. 2.4 Convulsions Drug induced Drug withdrawl induced

30. 2.5 Agitation

32. 2.6 Electrolyte disturbaces

33. 2.6 Electrolyte disturbaces

34. 2.6 Electrolyte disturbaces

35. 2.6 Electrolyte disturbaces

36. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

37. 3. Decontamination Decontamination may occurs to • EYE • SKIN • GUT

38. 3.1 Eye Decontamination • Irrigate the eye copiously with normal saline for 15-20 min. • Do not use acid or alkali irritating solutions. • Chemical burn victims should be instructed to place the face under running water with eyelids open • While moving to hospitals, the face should be immersed in a basin of water.

39. 3.2 Skin Decontamination • Exposed persons should rinse with cold water and then wash thoroughly with a non-germicidal soap. Repeat the rinse with cold water. • Corroded areas should be irrigated copiously with water or saline for at least 15 minutes. Do not use “neutralising solutions”. • Remove all contaminated clothes.

40. 3.2 Skin Decontamination • Some chemical exposures require special treatment : • Phenolic burns - polyethylene. • Phosphorus burns – copper sulphate solution • hydrofluoric acid burns – calcium gluconate application • For Tar – petroleum, mineral oil in petrolatum base should be applied.

41. 3.3 Gut Decontamination The various methods of poison removal from the gastrointestinal tract include: ■■ Emesis ■■ Gastric lavage ■■ Catharsis ■■ Activated charcoal ■■ Whole bowel irrigation.

42. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

43. 4. Poison Elimination • Forced Diuresis • Extracorporeal techniques • Haemodialysis • Haemoperfusion • Peritoneal dialysis • Haemofiltration • Plasmapheresis • Plasma perfusion • Cardiopulmonary bypass.

45. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care

46. 5. Antidote administration • An antidote is defined as a remedy to counteract or neutralize the effects of a poison. • In various poisonings antidotes are used to counteract the pathophysiology produced by a toxin.

47. 5. Antidote administration • Universal antidote comprises of: 1. Activated powdered charcoal—2 parts by weight 2. Magnesium oxide—2 parts by weight 3. Tannic acid—1 part by weight 15 gms of this powdered mixture should be added to half a glass of warm water before consumption.

48. Stabilise the patient (Stablization) • Evaluation • Removal of the poisoning material from the system (Decontamination) • Poison elimination • Antidote administration • Nursing and Psychiatric care