General morphological manifestations (the symptoms) mechanical asphyxia

The main morphological features of mechanical asphyxia are the following:
1) rich, which is bottled, intensely colored cadaveric spots appear quickly, within 30-60 min after death. They have a bluish-purple or bluish-purple tone. This is because asphyxia blood remains liquid, changing the color of her already in his lifetime, because the blood loses oxygen and taking carbon dioxide, becomes dark;
2) cyanosis of the skin of face and neck develops when convulsions during shortness of breath. This symptom occurs almost constantly, but can quickly disappear after the draining of the liquid blood in the lower part of the body;

subconjunctival ekhimozy
Fig. 5. Subconjunctival ekhimozy

3) petechial hemorrhages in the connection casing eyes, well identified in transition folds of the conjunctiva (Fig. 5). Occur in the phase of shortness of breath with a sharp rise in arterial and venous pressure. This feature is considered to be the most valuable;
4) involuntary defecation, urination, the selection of sperm, pushing out the mucus plug from the cervix is valuable, but not permanent signs;
5) dark, liquid blood in the heart and large venous vessels caused hypercapnia;
6) overflow blood right half of the heart, in comparison with the left associated with the difficulty flow of blood from the pulmonary circulation and the primary stop breathing while still working heart;
7) venous plethora of internal organs that have the same Genesis that previous sign;
8) subpleural and subepicardial hemorrhage (spot-p. Tardieu) - clearly distinguished, small, with a diameter of 2 to 3 mm deep dark red in color multiple, located under the pleura (often midlevel and diaphragmatic) and under the outer sheath of the heart (mostly on the back of its surface). In their origin play a part three main points: a) increased permeability of the walls of capillaries in acute oxygen starvation; b) sharp drops in blood pressure in the capillary network in phase shortness of breath; C) suction effect chest wall during the inspiratory shortness of breath.
It is noted that during hypoxia number of phospholipids in the adrenal glands and a thyroid gland increases in testicular tissue is reduced. Quite often is logged so-called tissue leukocytosis (infiltration) in the tonsils, the Appendix, the gastrointestinal tract). Response this is not specific and is found in other types of external influence (trauma, coma and others).
Histological examination in almost all cases, find extravasate in the brain in the bottom 4 of the ventricle.
It should again be noted that, although these symptoms are constantly encountered in mechanical asphyxia, they are not pathognomonic for her, as can occur in various combinations with other types of fast onset (acute) death. Of crucial importance in the diagnosis of asphyxia and particular species it belongs observed with them to the specific characteristics of specific mechanical asphyxia.

1. Give a definition of "asphyxia". What types of mechanical asphyxia.
2. What is the lifetime for mechanical asphyxia?
3. What are the common signs of mechanical asphyxia (acute death).
4. Describe their Genesis, morphological manifestations, diagnostic value.