GENRAL PRINCIPLES OF POISONING.pptx

it involves the general principles of poisoning treatment and various basic principles of management of poisoning IT IS USEFULL FOR THE IV.PHARM D STUDENTS AND MEDICAL STUDENTS

1. GENERAL PRINCIPLES INVOLVED IN THE MANAGEMENT OF POISONING SURESH BABU EMAND M.PHARM DEPARTMENT OF PHARMACOGNOSY VIKAS INSTITUTE OF PHARMACEUTICAL SCIENCES NEAR AIR PORT, RAJAHMUNDRY

2. TOXICOLOGY TOXICOLOGY – STUDY OF POISONS (GREEK WORDS) TOXICAN – POISON LOGOS – STUDY .

3. WHAT IS POISON Refers to any substance  injected into living body by any means (oral, i.v , inhalation/ dermal)  causes local/systemic effects (or even both)  results in ill-effects/ death of the individual

4. WHAT IS CLINICAL TOXICOLOGY IT IS   Branch of science, that deals with PATLET of poison/poisoning PATLET -Means : P : Properties of poison A : Action of poison T : Toxicity of poison (poisoning features) L : Lethal dose E : Estimation (How to confirm a particular poisoning) T : Treatment of the poisoning.

5. GENERAL PRINCIPLES OF POISONING   MANAGEMENT Includes the following major headings: i . STABILIZATION & EVALUATION ii . GUT DECONTAMINATION iii . POISON ELIMINATION iv . ANTIDOTE ADMINISTRATION v . NURSING CARE vi . PSYCHIATRIC CARE. STABILIZATION & EVALUATION

6. Refers to assessment & correction of life-threatening problems associated with the poisoning Always pay attention to ABCD of RESUSCITATION : A : Airway B : Breathing C : Circulation D : Depression of CNS.

7. A.AIRWAY Causes of  death from airway block: Airway obstruction Pulmonary aspiration of gastric contents Respiratory arrest.

8. Treatment involves: Optimize airway position to force the flaccid tongue out. Maximize airway opening (clear/suction airway) Perform endotracheal intubation ( nasotracheal / orotracheal ) iv . https://www.youtube.com/watch?v=qzIyTCx1Mfw (watch for nasotracheal intubation) v . https://www.youtube.com/watch?v=-5UVpGjXZcI (watch for orotracheal intubation) ENDOTRACHEAL INTUBATION TECHNIQUES

9. B . BREATHING Breathing difficulties  contribute to morbidity & mortality in patients with poisoning • Issues related to breathing include ventilatory failure, hypoxia & bronchospasm. VENTILATORY FAILURE: Causes of VENTILATORY FAILURE: Paralysis of ventilatory muscles

10. D.Depression of central respiratory drive ( CNS Depression) Botulinum toxin Antihistamines NMBs Barbiturates Nicotine Clonidine Organophosphates & carbamates Ethanol Snakebite Opioids Tetrodotoxin (found in puffer fish) Phenothiazine antipsychotics Sedative-hypnotics TCAs How to treat ventilatory poisoning • Endotracheal intubation

11. HYPOXIA Hypoxia is a  condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Causes of HYPOXIA: Inert gases Cardiogenic pulmonary edema Cellular hypoxia Pneumonia/ non- cardiogenic pulmonary edema CO2 Beta-blockers CO Aspiration of gastric contents Methane Quinidine CN Aspiration of hydrocarbons Nitrogen TCAs Cocaine Verapamil Opioids Procainamide Sedative-hypnotics Smoke inhalation

12. BRONCHOSPASM Defined as a  condition in which the lung muscles tighten  restricts airflow  makes breathing difficult! Causes of BRONCHOSPASM: Beta-receptor antagonists Organophosphate poisoning Chlorine gas Dust particles Drugs that cause allergic reactions Smoke inhalation Hydrocarbon aspiration

13. How to treat Bronchospasm  Administer supplemental oxygen Endotracheal intubation (if serious) Discontinue the offending drug or agent causing bronchospasm Remove patient from source of exposure to irritant gas/ dust particulate Give beta-2 agonist: - Beta-2-agonist R elaxes bronchial pathways causes bronchodilation - Salbutamol (5-15 mg, over 1-hour nebulization)  For excessive cholinergic stimulation: - Give anticholinergic (ipratropium bromide, 0.5 mg, every 4-6 hrs

14. Cholinergic overstimulation Increases secretion in respiratory pathways causes bronchospasm - Anticholinergic Reverses cholinergic effect (hypersecretion in airways) Reduces bronchospasm. For hyperreactive airways  give inhaled/ oral steroids (anti-inflammatory effect) For bronchospasm due to organophosphate/carbamate/other pesticide poisoning: Give atropine i.v (anticholinergic) Ipratropium bromide ( anticholinergic).

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

16. Evaluation If the patient is not in crisis, i.e. he is alert with normal speech and pulse, proceed to a complete, thorough, and systematic examination. As far as treatment is concerned, the emphasis should be on basic supportive measures.

17. Decontamination This is with reference to skin/eye decontamination, gut evacuation and administration of activated charcoal.

18. Poison Elimination Depending on the situation, this can be accomplished by diuresis, peritoneal dialysis, haemodialysis , haemoperfusion , etc.

19. Antidote Administration Unfortunately , antidotes are available for less than 5% of poisonings.

20. Nursing And Psychiatric Care General nursing care is especially important in comatose patients and those who have been incapacitated by the poison. Since some cases of poisoning leave behind persisting sequelae, adequate follow-up for a period of time may be necessary. Psychiatric intervention is frequently essential in suicidal overdose.

21. Stabilisation ASSESSMENT The Airway and Breathing Symptoms of airway obstruction include dyspnoea, air hunger, and hoarseness. Signs comprise stridor, intercostal and substernal retractions, cyanosis, sweating, and tachypnoea .

22. Normal oxygen delivery requires adequate haemoglobin oxygen saturation, adequate haemoglobin levels, normal oxygen unloading mechanisms, and an adequate cardiac output. Increasing metabolic acidosis in the presence of a normal PaO2 suggests a toxin or condition that either decreases oxygen carrying capacity (e.g. carbon monoxide, methaemoglobinaemia ), or reduces tissue oxygen (e.g. cyanide, hydrogen sulfide ). T he immediate need for assisted ventilation has to be assessed clinically, but the efficiency of ventilation can only be gauged by measuring the blood gases. Retention of carbon dioxide (PaCO2 > 45 mmHg or 6 Kpa ), and hypoxia (PaO2 < 70 mmHg or 9.3 Kpa ) inspite of oxygen being given by a face mask are indications for assisted ventilation

23. Lists some substances which are known to cause respiratory depression

24. Some drugs stimulate the respiratory centre: Amphetamines Atropine Cocaine Salicylates Some drugs are associated with non-cardiogenic pulmonary oedema Characterised by severe hypoxaemia Bilateral infiltrates on Chest X-ray, and Normal pulmonary capillary wedge pressure

25. Agents causing non-cardiogenic pulmonary oedema.

26. Some drugs cause or exacerbate asthma. The most important among them include NSAIDs, antibiotics like penicillins, cephalosporins, tetracycline, and nitrofurantoin, cholinergic drugs, chemotherapeutic drugs, and some diuretics.

27. Circulation Several drugs produce changes in pulse rate and blood pressure

28. Depression of Central Nervous System This is generally defined as an unarousable lack of awareness with a rating of less than 8 on the Glasgow Coma Scale (Appendix 1). However, the European Association of Poison Centres and Clinical Toxicologists (EAPCCT) are of the opinion that this scale while being very useful for trauma patients is inappropriate for acute poisoning. Several other scales have been proposed, including Reaction Level Scale, Comprehensive Level of Consciousness Scale (CLOCS), Coma Recovery Scale, Innsbruck Coma Scale, Reed’s Classification, etc., but the predictive value of all these scales remains to be ascertained

29. There are numerous causes for coma of which one of the most important is acute poisoning. A number of substances can induce coma, and it will require a great deal of astuteness and expertise to pinpoint the poison. Before proceeding to an elaborate exercise in diagnosis however, it may be desirable to first ascertain for sure that the patient is really comatose and not just pretending (psychogenic or hysterical coma). This is often encountered in cases of “suicide gesture” in contrast to “attempted suicide”

30. The former is an attention drawing gambit, where there is no real intention of ending one’s life. The telltale fluttering eyelids, the patient who is half-walked, half-dragged in by relatives, an elaborate suicide note, a phone call to a friend or relative informing them of the act, pill bottles strewn about, all may point to such a suicide gesture. In addition, the signs and symptoms manifested by the patient usually are out of proportion to the ingestion itself o the question is, how does the doctor humanely determine whether the coma is true or fake?

31. Several methods have been recommended of which the following constitute barbaric acts and must never be employed Pinching nipples or genitals, or repeatedly pinching any part of the body . Slapping the face hard, repeatedly Cotton pledgets or sterile applicator tips soaked with ammonia solution being inserted into the nostrils. Instead, the following steps are recommended: Perform a quick physical examination with particular attention to the breathing, vital signs, and the gag reflex. If these are normal, the coma is almost certainly psychogenic. Another indication is a tightly clenched jaw when attempts are made to open the mouth. However, first rule out seizure disorders.

32. Evaluation

33. Decontamination EYE Irrigate copiously for at least 15 to 20 minutes with normal saline or water. Do not use acid or alkaline irrigating solutions. As a first-aid measure at home, a victim of chemical burns should be instructed to place his face under running water or in a shower while holding the eyelids open . During transportation to hospital the face should be immersed in a basin of water (while ensuring that the patient does not inhale water).

34. SKIN Cutaneous absorption is a common occurrence especially with reference to industrial and agricultural substances such as phenol, hydrocyanic acid, aniline, organic metallic compounds, phosphorus, and most of the pesticides The following measures can be undertaken to minimise absorption*— ■ 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. It is preferable to strip the patient completely and provide fresh clothes, or cover with clean bedsheet . Y Phosphorus burns should be treated with copper sulfate solution. Y For hydrofluoric acid burns, use of intradermal or intraarterial calcium gluconate decreases tissue necrosis

35. Elimination The various methods of eliminating absorbed poisons from the body include the following: ■ Forced Diuresis ■ Extracorporeal techniques Y Haemodialysis Y Haemoperfusion Y Peritoneal dialysis Y Haemofiltration Y Plasmapheresis Y Plasma perfusion Y Cardiopulmonary bypass.