Forensic Pathology for Police - Brainshare Public Online Library

Autopsy Findings 437
Autopsy Findings
As alluded to in the introduction, there is typically no specific autopsy finding
in drowning victims that absolutely allows the pathologist to make a diagnosis
of drowning. As such, forensic pathologists include drowning amongst a variety
of case types that are considered “diagnoses of exclusion.” In other words, the
autopsy is negative or has various non-specific findings (see below), such that there
is no other adequate anatomic explanation for death, and the circumstances of the
death are such that drowning is the likely explanation. As described elsewhere in
this text, other case types that represent “diagnoses of exclusion” include certain
electrocution deaths, drug/toxin deaths, cardiac conduction system abnormalities,
seizure-related deaths, hypothermia, and hyperthermia, among others. In each, the
autopsy is usually negative regarding an anatomic explanation of death, and the
circumstances are such that the underlying cause of death can be ascertained.
Some important issues to address in any drowning death include the following.
Could the person have been dead before entering the water? What if there is underlying
severe natural disease that might otherwise explain death? A thorough death
investigation usually provides the answer to the first question, although occasionally
this question cannot be answered with certainty. Regarding the second question, the
circumstances in which death occurred, coupled with the details of the autopsy, will
probably provide the answer. Just because a person has a disease that could explain
death (such as severe coronary artery atherosclerosis) does not mean that they died
from that disease. The disease process may simply represent an “incidental” finding.
In contrast, certain natural disease processes, such as a ruptured myocardial infarct,
do not represent incidental findings. If a body is found in the water with a ruptured
myocardial infarct, it is likely that they experienced the natural death and then fell
into the water.
Occasionally, a drowning will be witnessed by other persons, with the victim
pulled from the water relatively soon after submersion. If the person is already dead,
rigor mortis may already be evident. Such “instantaneous” rigor results from the
fact that the drowning victim, while struggling to survive, used up much, if not
all, of their ATP during the struggle to avoid drowning. Recall that rigor mortis
becomes apparent after death as ATP is depleted within the muscles. If the ATP
is used up prior to death, rigor mortis will appear very quickly. In some drowning
victims, vegetation from the bottom of the body of water (lake, pond) will be seen,
clutched in the victim’s hands. Such a finding is sometimes referred to as “cadaveric
spasm,” and is another term that is used to describe the rapid onset of rigor mortis
that frequently accompanies drowning deaths (Fig. 16.4 and Disc Image 16.1).
Various nonspecific findings may be present in drowning deaths. The most consistent
of these is probably the presence of pulmonary edema fluid, although it is
not universally present in all drowning deaths. Pulmonary edema is characterized by
heavy lungs, as well as frothy fluid within bronchi, and sometimes the trachea, larynx
(Fig. 16.5), oropharynx and nasal passages. It is not unusual to see frothy fluid
exuding from the mouth and/or nose (Fig. 16.6 and Disc Images 16.2 and 16.3).
Hemorrhage within the lungs may accompany the pulmonary edema. It should be