GASEOUS ADVENTITIOUS PRODUCTS.
If the precise signification given to the term Adventitious Product be considered, it will be seen that gaseous rnatters are only truly ad ventitious when foreign in nature to the textures producing them. Air entering veitis lying within the suction-influence of the chest ; air swallowed; air entering the uterus and blad der from without ; and air diffused through the cellular menabrane, serous cavities, or paren chymatous organs, and derived from the air passages or alimentary canal, through a wound, ulceration, perforation or rupture of these ; consequently find no place under the present head. We shall here confine ourselves to a notice of gases produced by (a) local or ge neral anti-cadaveric decomposition, and (b) an alleged process of secretion.
(a) A man, aged twenty-five, died on the sixteenth day of continued fever (Peyerian type), and was examined by M. Bally eight hours after death. The body was soiled with blood, which had transuded through the skin of the thighs and scalp, and there was uni versal emphysema. The mesenteric glands contained gas which, like that in other parts of the body, took fire and exploded, Wlien brought in contact with the flame of a taper ; in burning it formed a tuft with a blue base and white apex, and appears to have consisted of proto-carburet of hydro gen, one of the ordinary products of putre faction, and is presumed to have been formed before death. (Art. EMPHYSEMA, Cyclopmd. of Surgery, vol. ii. p. 85.) Dr. Mouat (Ed. Med. and Surg. Journal, vol. hii. p. 4.27. l840) has published a case in which gas was found in the cellular tissue of the right thigh, on the, surface of the pericardium and pia mater, and in the right side of the heart and femoral vein. Accumulation of gas from de composition of fluid in the pleura, pericardium, peritoneum, joints, and tunica-vaginalis, has been described by various persons : hydro pneumothorax, however, it is to be remem bered, without perforation of the lung, is cer tainly of excessive rarity.
(b) It occasionally happens, as was first, we believe, noticed by Dr. Graves, that at a certain period of the progress of pneumonia, the. percussion-sians of pneumothorax may be discovered. Within the last year we have had in our wards a most interesting case of pure and simple pneumonia, unattended with the formation even of dry plastic matter in the pleura, during the progress of which a perfect tympanitic note (quite distinct front an amphoric or tubular one) continued for some time producible over the affected lung.
The only mode of accounting for it seemed by admitting the presence of air in the pleura, — and if such were the fact, that air must have been the produce of secretion. A sin. gular case is recorded by Sir F. Smith", in which a secretion of gas from the skin ap pears to have taken place.
(c) It is not uncommon to find bubbles or gas in the. veins of the pia-mater, and their presence is. not easily explicable. If the gas be regarded as of putrefactive origin, the dif ficulty is to explain why it occurs in bodies perfectly free from ordinary evidence of pu trefaction, and why it is limited to those par ticular veins. If it be regarded as natural gas. of the blood extricated during life, how collies it, that the blood in that particular part only should present it after death, and how comes it that, if really extricated there, it had not been carried on with the circulating fluid to the heart? The quantity of gas is too small in such cases to admit of analysis, —else perhaps a comparison between it and the gases of venous blood might throw some light on the matter.
But next comes the curious fact that where there is least blood there is most intra-venous air, —that is, where there is most of the pre sumed cause, there is least of the presumed effect. It is, in fact, in persons, who have died from hwmorrhage, that air has been found in greatest abundance in the veins. Lientaudt relates the case of a girl who died suddenly in a state of syncope, after having been repeatedly bled, and in whom the cere bral veins and choroid plexus were found full of air. M. Rerolle* has published several cases of the kind, where profuse hxmorrhage had existed ; in one of fatal epistaxis, the heart,. arteries, and veins, contained large quantities of air. Another of these is ren dered particularly remarkable by the fact that the gas (subcutaneous) took fire with slight detonation (as in M. Bally's case), and burned with a bluish flame ; here the patient had died of hmorrliage after removal of a tumour from the back, and was examined six hours after death, the thermometer (Reaum.) mark ing only + 2°. Similarly Dr. Graves has noticed emphysema of the abdominal parietes in a sufferer from frequent epistaxis.
In all this there is much mystery. M. Rerolle conjectures that, in such cases, air is absorbed by the radicles of the pulmonary veins, — the air would then have no claim to be considered adventitious, and the hy po thesis is, perhaps, not to be rudely rejected.
(Walter Hoyle Walshe.)