How is Preservation of viscera for chemical examination is done?

Viscera should be preserved if:
1.  if the death is suspected to be due to poisoning either by the police or doctor
2. Deceased was intoxicated or used drugs
3. Cause of death was not found after autopsy
4. In cases where am an unusual smell, color, or an unidentifiable material is detected in the stomach contents
5. Anaphylactic shock
6. Death due to burns
7. Advanced decomposition
8. Accident involving the driver of a vehicle or machine operator


The following must be preserved in all the fatal cases of suspected poisoning.
1. The stomach and its contents if empty, the wall should be preserved.
2. The upper part of the small intestine and its contents
3. Liver 200-300g
4. Kidney half of each kidney as one may be dysfunctional
5. Blood= 30ml[ min=10ml]
6. Urine -30ml


Levels of drugs in the muscle more accurately reflect blood vessels than kidney or liver
It is essential to present the contamination of a solid viscera with that of git  contents as the time since ingestion maybe determined from the relative amounts of poison in the stomach, intestines and solid viscera.
Poison found in the urine, unless added with evil intention, is proof of absorption or excretion.
7. Stomach contents are of primary value for estimating the quantity  ingested in acute overdoses and qualitatively in identifying substances that have been recently ingested.
CONTAINERS:
8. For  preservation of viscera, the glass bottles used should be of liter capacity, clean wide-mouthed white and fitted with glass stoppers.
9. Blood should be collected in screw-capped bottle of 30ml
10. When lungs or  other tissues are preserved for analysis for volatile substances then nylon bags should be used as theses bags are not permeable for the volatile substances.
PRESERVATIVE:
11. Saturated sodium chloride solution except in poisoning from  corrosive acids alkalis.
12. Rectified spirit, except in cases of suspected poisoning by alcohol, kerosene, chloroform, ether.
13. 10 mg/ml of sodium or potassium fluoride
14. 1 ml of conc. Hydrochloric acid or 100mg thymol or 100mg of sodium fluoride can be used for 10 ml urine as preservatives.
 Preservative is not necessary if,
15. Viscera can be analyzed within 24 hrs
16. If the sample can be kept in refrigerator
17. Bone, hair nails
18.  lungs for detecting inhaled poisons.
19. The viscera should not be preserved in formaldehyde because extraction of poison, especially non-volatile organic substances will be difficult