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Physiology InFocus: Novel Technologies in Physiology and Medicine
Forensic Medicine

This symposium will examine the practice of forensic medicine and its interaction with the biological sciences.  Forensic pathology regularly confronts important and controversial topics, such as the cause of death in Sudden Infant Death Syndrome, for which more questions than answers exist.  Finding these answers will require research by pathologists and biological scientists.  This symposium will feature four forensic pathologists, each speaking on a forensic topic that calls for research.  Each speaker will discuss a case or cases illustrating that topic.  The symposium is intended to show not only a glimpse of the practice of forensic pathology, but also the connection that continues to link autopsy pathology with biological science. 

Asphyxia: Forensic Pathologists frequently evaluate individuals who die unnatural, unexpected deaths due to asphyxia. Cases of drowning and suicide by asphyxial means will be presented as index cases. These cases will include mechanisms of oxygen ‘replacement’ and oxygen ‘deprivation’. Infant and child deaths with components of probable oxygen deprivation, like co-sleeping, “re-breathing”, and smothering will be presented. The relationship of these types of cases to the definition of Sudden Infant Death Syndrome (SIDS) will also be illustrated. Depending on the circumstances, these deaths may be accidents, homicides, suicides, or natural events. Autopsy findings and lack of consistent findings in deaths due to asphyxia will be discussed, highlighting the need for reliable, practical biomarkers in this group of decedents.

Objectives. Those who attend this symposium will: 1. Understand the abilities and limitations of autopsy pathology in determining the cause of death. 2. Learn of areas where further research is need at the interface of forensic medicine and basic biological sciences.

Overview of Presentations:

Pharmacogenomics: Pharmacogenomics is the study of individual difference in drug metabolism based on genetic variability.  Seventy-five percent of all drugs are metabolized by the CYP450 enzyme system in the liver.  Gene variations are due to single nucleotide polymorphisms, gene deletions, gene duplications, and others.  Individuals may demonstrate phenotypic variation, manifested as  poor, extensive (normal), or ultra-extensive (rapid) metabolizers.  Recent research suggests that up to sixty percent of methadone deaths may be related to genetic variations.  Pharmacogenetic testing promises to become a major tool in the investigation of sudden unexpected deaths.

Drug Abuse: Individuals who abuse drugs increase their risk of dying.  Usually examination reveals a lethal level of a drug of abuse, but sometimes autopsy reveals no anatomical or toxicological cause for death in these individuals. Research suggests that these deaths occur because drug abuse induces some change that persists after the drug is no longer detectable in the body.  Research shows that chronic cocaine use alters endothelial cell function, rendering addicts susceptible to ischemia by thrombosis of injured vessels, accelerated atherosclerosis, or by vasoconstriction and vasospasm.  Chronic cocaine treatment enhances the arterial responsiveness to vasoactive substances in dogs, enhancing peripheral vasoconstriction and cardiac ischemia.  Finally, myocardial hypertrophy is statistically significantly higher in men who used cocaine.

Restraint/Force: Restraint or the application of force on suspects during an arrest is sometimes associated with sudden death.  One particular topic gaining publicity in the media is the Taser, which applies high voltage, low amperage current upon engagement.  Despite extensive safety testing of the device, including thousands of uses on police officers during training, a few suspects have died shortly after application of the Taser.  A number of complicating factors exist, such as the use of illicit substances by the suspect, agitated delirium, and pre-existing cardiac conditions.  These factors may also play a role in deaths associated with physical struggle during the arrest, the use of the “choke hold” or “carotid sleeper hold”, and hog-tying.  This subset of sudden deaths occurring during restraint or the application of force is likely due to a combination of external physiological stressors and the underlying (patho)physiology of the suspect during a particularly tense situation.