Forensic Autopsy Findings in Poisoning Cases

External Review in Poisoning Autopsies

Cadaverous Phenomena

• Lividity: Carbon monoxide (CO) presents redder than normal; asphyxia results in dark red; methemoglobin-forming poisons appear brownish.
• Rigidity: Carbon monoxide rigidity is higher than normal, often giving the deceased the appearance of a boxer. Strychnine poisoning causes early and lasting rigidity.

Color of Skin and Mucous Membranes

• Carbon Monoxide and Cyanide Poisoning: These present a more rosy appearance than the usual appearance of life.
• Phosphorus Poisoning: Results in a yellowish skin tone.
• Methemoglobin-forming Poisoning: Results in a cyanotic or brownish appearance.

Traces of Vomit and Feces

Examination may reveal bloody vomiting (hematemesis) or bleeding of the upper or lower digestive tract caused by corrosive metals. Other findings include diarrheal stools and vomit containing pill remnants.

Skin Lesions

Inspect for skin punctures, burns from corrosives (e.g., on the mouth or lips), and occupational dermatoses resulting from toxic exposure in the workplace.

Internal Review and Organ Examination

Presence of Scents

Particular attention should be paid to scents when opening cavities. Distinctive smells include:

• Cyanide (CN): Smells of bitter almonds.
• Alcohol: Distinctive ethanol odor.
• Chloroform: Presents a fruity scent.

Gastrointestinal Study

The study involves the stomach, its contents, and the intestines. The procedure requires ligating both ends of the stomach with a line before removal. It is then placed on adequate support, opened, and the contents are examined. Do not open the stomach in situ. The same method applies to the intestines. Examiners look for mucosal lesions, remnants of drugs, or pills. Findings may include congestion of the mucosa due to alcohol or burns on the lining of the esophagus from swallowing acid. Chemical orientation tests should never be performed directly on the body.

Organic Lesions and Systemic Effects

Cardiovascular System

Fewer injuries are usually found in the heart; however, it should always be opened to examine the content for sampling. Many poisoning deaths stem from cardiovascular causes. Cardiac arrest from poisoning usually occurs in the left ventricle, often leading to pulmonary edema.

Renal Injuries

Injuries involve the glomerular capillaries first, followed by the entire nephron. Conditions include:

• Glomerulonephritis: Caused by Mercury (Hg), Arsenic (As), etc.
• Fatty Degeneration: Caused by Arsenic (As) or Phosphorus (P).
• Sclerosis: Caused by Lead (Pb) or Phosphorus (P).
• Oliguria and Anuria: Caused by Mercury (Hg), Arsenic (As), or Quinine.
• Toxic Hepatonephritis: Where liver and kidney lesions develop simultaneously.

Hepatic and Pulmonary Injuries

• Hepatic: The liver is the most affected organ as it is the quintessential detoxifying organ. Injuries include cirrhosis and hepatic steatosis.
• Pulmonary: Injuries occur due to irritation or anoxia. Left heart failure causes pulmonary congestion; cocaine use also results in significant congestion.

Cerebral and Blood Injuries

• Cerebral: Findings include edema and petechiae. The cortex may appear darker than the cerebral spinal circulatory failure seen in ecstasy cases, allowing for venous hyperemia.
• Blood: Injuries often manifest as hemolysis.

Stomach and Intestines

Examiners look for specific fragrances, the color of the stomach wall, and congestion or irritation of the mucous membrane due to substances like alcohol, nicotine, Mercury (Hg), Lead (Pb), Arsenic (As), or Phosphorus (P).

Rules for Collecting and Shipping Samples

Procedures are governed by the Ministerial Order of 8/11/96, published in the BOE on 23/12/96.