Tuesday, November 2, 2010

Forensic Post: Asphyxial Death; Drowning

Not like my everyday post, today I like to talk about…. DEATH… More specifically, asphyxial death. Why? Because it’s a big and important topic, with many medico legal and interesting aspect and also because I never get the chance to actually observe one yet (cis..!).

Asphyxia is the condition of lack of oxygen arising from an obstruction to the air passage from within or out. Generally, those who died due to asphyxia might have cyanosis, general visceral congestion, venous congestion, increase venous back pressure, stasis of the blood, pulmonary edema, serous effusion, post mortem fluidity of blood, petechial hemorrhage, cardiac dilation, biochemical changes and pseudo-Rouleaux formation due to heamoconcentration in the blood.

Under asphyxia we have drowning, hanging, sexual asphyxia, strangulation, manual strangulation (or throttling) and last but not least, suffocation. Well they all sounds the same, but there are not actually. Since there are too many of it, maybe I talk about the others in my other post, today, we talk about, drowning. Death due to drowning…


Is when the air entry is prevented from entering the lungs by water or any form of fluid matter into which the head had fallen and remained in. Get it? You know, head in water, air prevented in, and cannot breath. Note here, it is the head that remained in, so if someone were to be push in a small bucket containing water (or even pasta sauce) just enough to immerse the head, and the person dies because of it,  it is already consider as drowning. (and I learn that from watching detective conan haha)

Before jumping to any conclusion, there are a few aspects of drowning to think about
Was death really due to drowning? What was the motive? I mean they might have died due to natural disease before falling in the water or suffer a natural disease while they are in the water. It could also be an injury before they fell or be thrown in the water or died from other effect of immersion other than drowning… so how can we tell? Before starting the autopsy, we have to answer a few questions where we go back to the basics, the 4 manner of death, accidental, suicidal, homicidal or natural… So the purpose is to rule out what’s not and rule in what it is. So lets go through…

Signs of Drowning

What are the post mortem signs of drowning? The signs could be further divided to external and internal signs which can further be subdivided to presumptive and specific. Basically, the presumptive external signs are bodies which are wet, covered in seaweeds, cyanosis, congested eyes, presence of “washerwoman’s skin”, “goose skin” or cutis anserine, and retraction of scrotum and penis. But more importantly are the specific external signs which are fine white, tenacious, lathery froth or foam like soap with blood oozing from the mouth and nostrils. This can be reproduced by exerting pressure to the chest. Another important sign is the cadaveric spasm, which is the clasping or grasping of objects found in the water. For the internal signs, the white tenacious foam can also be found in the air passages to the terminal bronchiole. There can also be logging and ballooning of the lungs.

Laboratory test

When there are drowning bodies, laboratory test of the pulmonary and blood is important to determine the possible cause of death and the actual place the drowning took place. An important key point in the lab test is the diatoms. These are microscopic unicellular algae that can be found in certain water. Since it is indestructible, we can determine whether the victim was alive or not before they were immersed in the water by looking for these diatoms in the lungs, blood, brain, liver, kidneys and bone marrow. If they are alive, these diatoms have time to circulate around throughout the body. By comparing the diatoms too, we can determine whether the alleged crime scene (locus of crime) was true or not.

Don’t forget about the blood! Since the bodies died in the water, we can also determine whether the water was salty or fresh water by looking at the blood. Is it crenated or are there burst spherocytes?

What about the pulmonary tissue? There will be two aquosum. The first one is emphysema aquosum, where the alveoli is filled with water, mucous and also air, the inter alvelolar septa is also ruptures. Another one is oedema aquosum where the inter-alveolar space is filled with water, the interalveolar membrane is widened due to edema and it may also rupture.

We should also do biochemical test to check the chloride content, magnesium and specific gravity of the blood.

Of course there are other things regarding drowning I didn’t cover here, but basically that’s about it. So, thank you for reading! See you again in the other forensic post! (^_^)

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