Poisoning/Overdose

1. Poisoning/Overdose General Management Poisoning is Exposure to substance that is toxic in anyamount

2. Overdose Exposure to substance in excessamount resulting in toxic effects

3. 1998 TESS* Data • 2,241,082 reported human exposures • 97.9 % at home • Peak volume 4pm-10pm • 91% of calls 8pm-midnight *The Toxic Exposure Surveillance System (US based)

4. Exposures by Age • < 6 years old 52.7% • < 3 years old 39.6% Fatalities • 775 fatalities • 0.03% of total exposures • ages 20 - 49 years = 56% • >6 years = 2.1%

5. Number of Substances • 92.8% of all cases--one substance • 44.7% of fatal cases-->2 substances

6. Management Location • Managed on site 75.2% • Treated, released at ER only 12.3% • Admitted to critical care 2.7% • Refused referral * 2.0%

7. Therapy • No therapy 11.9% • Observation only 12.7% • Decontamination only 59.6% • Activated charcoal 6.8% • Ipecac 1.2%

8. Most Common Substances • Cleaning substances 10.2% • Analgesics 9.6% • Cosmetics 9.4% • Plants 5.5% • Foreign bodies 4.6% • Cough, cold 4.5% • Bites, stings 4.1% • Insecticides, pesticides, rodenticides 3.9% • Sedative, hypnotics, antipsychotics 3.2% • Antidepressants 3.0% • Hydrocarbons 3.0% • Alcohols 2.5%

9. Largest Number of Deaths • Analgesics 264 • Antidepressants 152 • Stimulants, street drugs 118 • Cardiovascular medication 118 • Sedatives, hypnotics 89 • Alcohols 56

10. Indicators • Sudden onset of CNS signs: • Seizures • Coma • Decreased LOC • Bizarre behavior • Sudden onset of: • Abdominal pain • Nausea • Vomiting

11. Indicators cont • Sudden onset of unexplained illness • Bizarre, incomplete, evasive history • Trauma (>50% of adult trauma EtOH, drug-related) • Pediatric patient with arrhythmias

12. History • What? • How much? • How long? • Multiple substances? • Treatment attempted? How? Whose advice? • Psychiatric history? • History of suicide?

13. Scene Survey • Check out scene for : • 1 • 2 • 3 • 4 • Where do you look for clues?

14. General Management • SupportABC’s • Secure airway, secure with advanced airway if needed • Ensure adequate oxygenation, ventilation • Maintain adequate circulation • Monitor ECG • Obtain vascular access • Manage hypotension initially with volume • Use vasopressors cautiously

15. General Management • Keep patient calm • Maintain normal body temperature • Evaluate nature/toxicity of poison • Check container, package insert, poison center information • Treat the patient, not the poison

16. General Management • Rule out (differential diagnosis) • Trauma • Neurological disease • Metabolic disease • Base general management on route of poison entry

17. Ingestion Slow movement from injection site throughout body Poison Entry • Prevent absorption from GI tract • Inhalation • Remove from exposure; Support oxygenation, ventilation • Absorption • Remove from skin surface • Injection

18. Ingested Poisons Objective Remove from GI tract before absorption occurs

19. Ipecac • RARELY used anymore • If used, has to have been initiated within few minutes after ingestion • Vomiting in 20-30 minutes • Only removes about 32% of contaminate • Many contraindications

20. Ipecac • Dose • 15 cc if 12 months to 12 years old • 30 cc if >12 years old • Follow with 2-3 glasses of water • Keep patient ambulatory if possible

21. Ipecac • If no vomiting after 20 minutes, repeat • When emesis occurs, keep head down • Collect, save vomitus for analysis

22. Ipecac • Contraindications • Comatose or no gag reflex • Seizing or has seized • Caustic (acid or alkali) ingestion • Low viscosity hydrocarbon ingestion • Late term pregnancy

23. Ipecac • Contraindications • Severe hypertension, cardiovascular insufficiency, possible AMI • Ingestion of: • Strychnine • Phenothiazines (Thorazine, Stellazine, Compazine) • Tricyclic antidepressants • Iodides • Silver Nitrate

24. Lavage • Commonly used in ED’s • Removes about 31% of substance • Helps get activated charcoal in patient, especially if patient is unconscious • Not helpful for sustained release tablets • Will not remove large tablets

25. Activated Charcoal • Adsorbs compounds, prevents movement from GI tract • Very effective at adsorbing substances • Binds about 62% of toxin • Dose • 5 - 10X estimated weight of ingested chemical

26. Activated Charcoal • Inactivates Ipecac • Do not give until vomiting stops • Do not give with • Cyanide • Methanol • Tylenol (+) • Containers must be kept airtight • Can be given PO via slurry or by NG

27. Inhaled Poisons Objective: Move to fresh air; optimize ventilation and protect personnel from exposure

28. Absorbed Poisons Objective: Remove poison from skin Liquid: Wash with copious amounts of water Powder: Brush off as much as possible, then wash with copious amounts of water Protect personnel from exposure

29. Dilute / Irrigate / Wash • Use soap, shampoo for hydrocarbons • No need for chemical neutralization - heat produced by reaction could be harmful

30. Eye Irrigation • Wash for 15 minutes • Use only water or balanced salt solutions • Remove contact lenses • Wash from medial to lateral

31. Examples of Specific Toxins

32. Acids • Examples • Toilet bowl cleaner • Rust remover • Phenol (carbolic acid) • Hydrochloric acid • Severe burning of stomach • Absorption, systemic acidemia

33. Acids • Loss of airway = most immediate threat • Secure airway against edema • IV with RL, NS for volume loss • Emesis, gastric lavage contraindicated • Dilution with water, milk NOT recommended

34. Alkalis • Examples • Drain cleaner • Washing soda • Ammonia • Lye (sodium hydroxide) • Bleach (sodium hypochlorite) • Severe burning of esophagus, stricture formation

35. Alkalis • Loss of airway = most immediate threat • Secure airway against edema • IV with LR, NS for volume loss • Emesis, gastric lavage contraindicated • Dilution with water, milk NOT recommended

36. Hydrocarbons • Examples • Kerosene • Gasoline • Lighter fluid • Turpentine • Furniture polish

37. Hydrocarbons • Signs/Symptoms • Choking, coughing, gagging • Vomiting, diarrhea, severe abdominal pain • Chemical pneumonitis, pulmonary edema If the patient is coughing, aspiration has occurred

38. Methanol methyl alcohol wood alcohol wood naphtha

39. Methanol • Sources • Industry • Household solvents • Paint remover • Fuel, gasoline additives • Canned heat • Windshield washer antifreeze

40. Methanol • Toxic dose • Fatal oral: 30-240ml • Minimum: 100 mg/kg • Example • Windshield washer fluid 10% Methanol • 10 kg child needs only 10 cc to be toxic

41. Methanol • Mechanism of toxicity • Methanol slowly metabolized to formaldehyde • Formaldheyde rapidly metabolized to formic acid • Acidosis • Ocular toxicity

42. Methanol H H C Formaldehyde H O H O H Aldehydedehydrogenase H O C Formic Acid H O O C H H C _ O H + Methanol Metabolism Alcohol dehydrogenase

43. Cyanide

44. But first… • A little review of biochemistry and biophysics

45. Staying alive requires energy... • The natural tendency of the universe is for things to become more disorderly. • This trend toward disorder is called entropy. • Complex systems (including us) don’t tend to last long, unless… • They have a constant supply of energy to combat entropy.

46. Organisms capture and store the energy they need in the form of... Adenosine Triphosphate (ATP) • The “currency” cells use to pay off the energy debt built up fighting entropy. • Formed by capturing energy released as the cell breaks down large molecules through glycolysis and the Krebs Cycle.

47. Putting It All Together • Cells have to have energy to stay alive. • Cells get energy by breaking down glucose in two phases: glycolysis and the Krebs Cycle. • Glycolysis yields 2 ATP and pyruvate. • Pyruvate is changed to acetate (acetyl-CoA) and sent to the Krebs Cycle. • The Krebs Cycle strips hydrogen and electrons off acetate and feeds them into the electron transport chain. • Movement of electrons down the transport chain releases energy which is trapped as ATP. • At the end of the chain, the electrons combine with hydrogen and oxygen to form water. • CN messes with this !

48. Cyanide • Chemical, plastic industries • Metallurgy, jewelry making • Blast furnace gases • Fumigants, pesticides • Present in various plants • apples, pears, apricots, peaches, bitter almonds • Remember there is CN gas released by BURNT plastics (e.g fire!!)

49. Cyanide Antidote Kit • Amyl nitrite, sodium nitrite • Only be used in serious cyanide poisonings • Can induce life-threatening tissue hypoxia secondary to methemoglobinemia • Sodium thiosulfate • Can be used by itself • Is relatively benign

50. Salicylates