What Does a Forensic Pathologist do?
As a physician who specializes in the investigation of sudden, unexpected and violent deaths the forensic pathologist attempts to determine the identification of the deceased, the time of death, the manner of death (natural, accident, suicide or homicide) the cause of death and if the death was by injury, the nature of the instrument used to cause the death.
First, the forensic pathologist gathers a history as to how the death occurred and often obtains the past medical history of the deceased as well. Next, the forensic pathologist examines the body externally and then internally taking small samples of tissues to examine under the microscope for abnormal changes not visible to the naked eye. This postmortem examination is known as an autopsy.
Autopsy
During the course of the autopsy, various laboratory tests may be undertaken, including x-rays, retention of body fluids such as blood and urine and small samples of tissues such as liver or brain for toxicological analysis and cultures of body fluids and organs for evidence of infection.
When all of the information including the history, the results of the autopsy and the laboratory tests are completed, the forensic pathologist correlates all the information and draws conclusions as to the cause and manner of death. A report is then prepared summarizing these findings.
The forensic pathologist can expect to be subpoenaed to testify before courts and other tribunals about the pathologic findings and conclusions. Coroners, medical examiners and pathologists provide copies of their official reports to parties, such as insurers or public agencies, having a legitimate interest in the cause and manner of death of citizens.
How does the forensic pathologist use the history, external physical examination, autopsy and laboratory studies to determine the cause and manner of death?
The history is the beginning of the investigation and is of utmost importance in making the determination of cause of death. The scene investigation may disclose drugs or toxins which may be related to the cause of death. Some poisonous agents are not detected on a routine drug screens therefore the pathologist must have knowledge of medications and toxins in order to request the specific analytical tests needed to detect them.
An example would include the "sniffing" of aerosol propellants, a risky activity which has been frequently reported in teenagers. Sniffing of propellant substances can cause sudden death by precipitating lethal cardiac arrhythmias. A special analysis (gas chromatography by head space analysis) is required to detect the chemicals in the blood.
Determining Cause of Death
In other cases there may be sufficient natural disease to account for death but the individual may in fact have died of a drug overdose or other subtle cause. In the case of drowning and suffocation the autopsy findings may not be specific and police investigation may be critical to the understanding of the death.
Data developed by coroners, medical examiners and pathologists is studied by medical epidemiologists and health and safety agencies to develop strategies to prevent disease and injury, thereby saving lives. The data developed about injuries and fire deaths led to legislation requiring seat belts in vehicles and smoke detectors in building construction.
In the examination of skeletal or severely decomposed remains, the forensic pathologist needs a working knowledge of multiple methods of identification including forensic anthropology in order to establish identity. If sufficient skeletal parts remain, the pathologist may be able to determine the age, race and sex of the individual and sometimes estimate the length of time since death. Occasionally, specific markings on the bones may enable the pathologist to come to a conclusion as to the cause of death.
What is the importance of performing an autopsy in someone in whom the cause of death is "obvious"?
The importance of examining people in whom the cause of death appears obvious is several fold. In the case of shootings or other fatal assaults the forensic pathologist, during the course of the examination, may recover bullets or other important trace evidence. In the case of motor vehicle occupants, it is important to determine who was driving and to assess driver factors, vehicle factors or environmental factors that might have caused or contributed to the crash.
Forensic autopsies may identify inherited diseases that constitute a risk for next of kin. Examples include certain types of heart disease (premature atherosclerosis, hypertrophic cardiomyopathy) and certain kinds of kidney disease (adult polycystic kidney disease). Notifying the family would be an important service to the living. In individuals who have undergone medical treatment after collapse or injury it is important to share the findings with the treating physicians for educational purposes.
How does an autopsy authorized by the next-of-kin on a patient dying in the hospital of a natural disease differ from an autopsy authorized by law as part of a medicolegal investigation?
The hospital autopsy is often performed on individuals in whom the disease causing death is known. The purpose of the autopsy is to determine the extent of the disease and/or the effects of therapy and the presence of any undiagnosed disease of interest or that might have contributed to death. The next-of-kin must give permission for the autopsy and may limit the extent of the dissection (for example the chest and abdomen only, excluding the head).
A medicolegal (forensic) autopsy is ordered by the coroner or medical examiner as authorized by law with the statutory purpose of establishing the cause of death and answer other medicolegal questions. The next-of-kin do not authorize and may not limit the extent of the autopsy. Common questions include the identity of the deceased person, the time of injury and death and the presence of medical evidence (for example bullets, hair, fibers, sem*n).
Observations made at autopsy elucidate how and by what weapon lethal injury was inflicted.During the course of the forensic autopsy, blood and other body fluids are routinely obtained in order to check for alcohol and other drugs. The forensic autopsy should be complete (including the head, chest, abdomen and other parts of the body as indicated).
