Since many cases have been observed in which both sides of the heart may be partly filled or both be empty and flaccid, or the left side distended more than the right, we are obliged to regard the exceptions concerning this post-mortem sign of drowning as co-extensive with the rule.
Excessive fluidity of the blood depends upon the rapidity with which the drowning took place. Slight hydræmia occurs in rapid submersion, but when the drowning has taken place slowly a large amount of water passes into the blood. In certain poisonings by opium this fluidity also exists; but it is claimed that analysis and the spectroscope may clear up the diagnosis.
Hydræmic engorgement of the liver is regarded as a characteristic fact by Lacassagne, who claims to be able to diagnosticate drowning from a single examination of this organ.[944]
It is now generally admitted that the presence in the stomach of a certain quantity of liquid in which the body was found immersed may be considered as a sign almost certain of asphyxia by submersion.
Dr. Fagerlund concludes from his experiments that liquids do not penetrate after death either the stomach or anus unless strong pressure be made. But when asphyxia occurs in water the liquid is found in the stomach and the intestines, where it is helped on by peristaltic movements. The pylorus is an obstacle to the passage of this water, the movement of which is easier when the stomach is empty and the submersion prolonged.[945]
The quantity and quality of the water may constitute important evidence; but to be of full value the water or other fluid found in the stomach ought to be the same as that in which the immersion has taken place.
The liquid, which may have been taken just before drowning, should not be noticed unless it exceeds half a pint; but anything peculiar in the fluids, either of the lungs or stomach, should be subjected to microscopic or other examination.
Presence of water in the middle ear is regarded as a thanatological sign of great value. Dr. Bourgier claims as the result of his examination that 23 cases out of 27 had water in the middle ear. Several German observers pretend to have found amniotic liquid in cases of fœtal asphyxia. The fluid may be aspired by a small pipette.
Many of the foregoing signs and lesions disappear or undergo variable alterations after sojourn in water, putrefaction, etc. They may, as they have done in the past, give rise to many controversies, so that presumptions only can be established. Hence the necessity for careful and detailed necropsy in such cases, with a view not only to minimize conjecture and uncertainty, but to prevent opposing counsel from entering the plea of negligence and incompleteness.