Autopsy Pathology and Forensic Pathology
Autopsy practice
Two types: hospital (clinical) autopsy, requiring consent, and medicolegal autopsy, ordered by a legal authority. The autopsy begins with external examination, photography, and documentation, then internal examination with evisceration, organ dissection, and sampling for histology, toxicology, and microbiology. Cause, mechanism, and manner of death must be distinguished. Cause is the disease or injury; mechanism is the physiologic derangement; manner is natural, accident, suicide, homicide, or undetermined.
Postmortem changes help estimate time of death: algor mortis, rigor mortis, livor mortis, decomposition. Rigor begins in small muscles and resolves over hours to days; livor fixes after several hours. Artifacts from resuscitation, intubation, and decomposition must not be mistaken for disease.
Forensic pathology
Wounds: abrasions, contusions, lacerations, incised wounds, stab wounds, gunshot wounds. Gunshot wounds show entrance, exit, powder tattooing, and soot. Asphyxia, drowning, burns, and child abuse require careful documentation. Chain of custody and specimen labeling are essential for toxicology. Sudden cardiac death, pulmonary embolism, aortic dissection, and cerebral hemorrhage are common autopsy findings.
Traps
Questions mix cause with manner, or mislabel postmortem lividity as bruising. Hospital autopsy consent does not cover medicolegal cases.
Rule of thumb: ask "what started the chain?" for cause, and "was it natural, accidental, suicidal, homicidal, or undetermined?" for manner.
Worked example: a gunshot wound to the chest - cause: gunshot wound; mechanism: hemorrhage; manner: homicide or accident depending on circumstances.