(5) Death by suffocation retards the process of cooling.
(6) The body may be cold externally, but possesses a considerable amount of heat when the internal organs are exposed. Persons who have died of cholera, yellow fever, or suddenly of some acute disease—rheumatism—may retain for some hours a considerable amount of heat. It has even been asserted that in some diseases—cholera—there is an increase of temperature soon after death (Laycock), also after death due to some diseases of the nervous system as in pontine hæmorrhage and cerebro-spinal meningitis, and following prolonged muscular spasm as in tetanus.
(7) Most bodies, under ordinary circumstances, are, as a rule, quite cold in from eight to twelve hours after death. The rate of loss of temperature depends upon the difference between that of the body and its surroundings; it lessens as the body cools. It takes at least twenty-four hours for it to fall to the heat of the surrounding atmosphere.
6. Relaxation, primary flaccidity, more or less general, of the muscular system takes place.
“If the above signs are alone present, death must have taken place in from ten to twelve hours at the longest” (Casper). Exception: cadaveric spasm.
7. Want of elasticity in the eyeball: flaccidity of the iris. This condition invariably occurs in from twelve to eighteen hours after death.
8. Flattening of the muscles of those parts on which the body rests, due probably to loss of vital turgidity.
9. Hypostasis.—Suggillation, or post-mortem staining, is due to the gravitation of the blood to the most dependent parts of the body not subject to direct pressure. The hypostatic marks begin to form in from eight to twelve hours after death, and increase in size till putrefaction sets in. They alter their position with changes in the position of the body so long as the blood remains fluid, but when it has coagulated they remain permanent. Hypostasis may be mistaken for an ecchymosis or a bruise, and in the lungs for congestion, inflammation, &c. Errors may also occur with regard to the brain, stomach, kidneys, and intestines: in the last, the redness of inflammation is seen all over the parts, whereas the coloration of hypostasis is interrupted, and this is best shown by drawing out the convolutions. The heart is an exception to the rule, but it may contain clots varying in size and colour. These are post-mortem formations. The use of the word suggillation is objectionable, as it has been used in opposite senses by Continental and British authors—some writers restricting the term to ecchymosis proper, others using it as synonymous with cadaveric lividity or external hypostasis.
Cutaneous Hypostasis
(1) Meaning of the expression.—The gravitation of the blood in the capillaries after death, in obedience to the laws of inert matter.