CARBAONMONOXIDE POISONINGindus medical.pptx

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1. CARBON MONOXIDE POISONING BY DR. FAIZA AFTAB MEMON (MCPS) LECTURER IN FORENSIC MEDICINE DEPARTMENT

2. PHYSICAL PROPERTIES MODE OF ACTION SIGNS & SYMPTOMS FATAL DOSE & FATAL PERIOD DIAGNOSIS TREATMENT POSTMORTEM APPEARANCE MEDICOLEGAL IMPORTANCE OBJECTIVES

3. . It is a colorless, odorless, non-irritating gas . A gas slightly lighter than air. It is a flammable gas, burns with a blue flame. PHYSICAL PROPERTIES

4. CO has 250-300 times more affinity for hemoglobin than oxygen, and combines with it very rapidly . Resulting in reduced oxyhemoglobin saturation & decreased blood oxygen carrying capacity. Depriving the tissues of oxygen supply (tissue anoxia ). MODE OF ACTION

5. S/S OF POISONING COHb level [%] Symptoms 10 to 20 Exertional dyspnea Mild frontal headache 20 to 30 Increasing dyspnea, severer headache 30 to 40 Vertigo, blurred vision confusion , nausea 40 to 50 Weakness , trismus , muscle spasms, vomiting , tachypnea 50 to 70 Convulsion, respiratory, failure, coma, bullous lesions commonly develop in the skin (as in the case of barbiturates coma) Over 70 Coma

6. A simple test that by done by the attending physician is to dilute 1ml of the patients blood with 10ml of water in a test tube and add to it 1ml of as 5% solution of sodium hydroxide. carboxy hemoglobin [COHb] is present, the solution will turn - Straw yellow (<20%COHb) or - Pink (> 20% COHb) in the case of normal blood, i.e. ox hemoglobin, the solution turn brown in color COHb level in the blood measure by spectrophotometry DIAGNOSIS

7. CARBONMONOXIDE: DIAGNOSTIC TEST Spectroscopic test If blood is examined spectro specially 2 band of COHb b/w D&E will be found in the yellow-green region. A calibrated instrument is necessary to appreciate this difference. Spectroscopic examination of blood is negative unless the amount of carbon monoxide in the blood exceeds 20-25% Kunkel’s test or Tannic acid test A sample of suspected blood is dilute with 4times its volume & water and a few drops of 3% aqueous tannic acid solution are added to it. It is then shaken well. If carbon monoxide is present, it forms a pinkish white precipitate. Blood saturated even with 10% carbon monoxide responds to this test. Hoppe-seyler Test A sample of suspected blood is dilute with about 20 times its volume of water and 10 drops of 10% caustic soda is added to it. Normal blood produces a dirty greenish brown color while blood containing carbon monoxide retain its bright red color.

8. 50-70 saturation of blood as carboxy hemoglobin [COHb ] O.1 % of carbon monoxide in the atmosphere is fatal. FATAL PERIOD: Not fixed or 15- 20 minutes is fatal. FATAL DOSE

9. Immediate removal from the source of exposure Administration of 100% oxygen or hyperbaric oxygen. Monitor cardiac and respiratory status. Watch for increased intracranial pressure. If there is increased ICP treat with corticosteroids hyperventilation head elevation & mannitol , Convulsions can be controlled with IV diazepam of Phenytoin. Supportive measures TREATMENT

10. The outstanding feature is the cherry pink color imparted to the body particularly evident in areas of hypostasis and in the blood poisoning by cyanide results in a brick red color. Pulmonary and cerebral edema. Congestion of viscera with petechia , on the lungs and heart and some times in the white matter of brain. POSTMORTEM APPEARANCE

11. Automobile exhaust: contain up to 9% CO. Improperly vented gas: Water heaters, kerosene space heaters charcoal grills, etc. Fire: smoke contains variable concentration of CO. Paint removers: especially those which contain ethylene chlorine . . Endogenous CO: during hemoglobin catabolism, carboxyhemoglobin is produces in the body endogenously reaching up to a level of 0.4-0.7%. Hemolytic anemia can raise this to 8%. Tobacco smokers may have up to 9% CO- Hb levels SOURCES

12. SUICIDAL HOMICIDAL ACCIDENTAL MEDICOLEGAL IMPORTANCE

13. USES CO is used as a fuel for heating and lighting DIFFERNTIAL DIAGNOSIS OF CARBON MONOXIDE POSIONING - ALCHOHOLIC INTOXICATION - CEREBRO VASCULER ACCIDENT - MIGRAINE - EPILESPY - MENINGITIS - ENCEPHALITS - HYPER VENTILATON SYNDROME - FOOD POISONING