Dr. Golis, from observing the marked connexion "between the turgescent state of the brain from chylopoietic disturbance, and its serous inflammation, has concluded, that it essentially pertains to it;" consequently, that "whenever it occurs, it is a part of it;" that it should be considered as forming the first stage of the disease, and that in all instances, it precedes the excitement. He has, for the same reason, constituted all the symptoms of the chylopoietic disease into the first stage of hydrocephalus. Dr. Ayre shows, however, that this state of turgescence, is not essential to the disease, and is only a sympathetic effect, which in the majority of instances, requires no treatment, (at least a very subordinate one,) other than that of the primary affection. He concludes his remarks on hydrocephalus, with the following words.
"The cerebral turgescence and disturbance, therefore, in whatever degree they may exist, are only, when sympathetically produced, to be considered as morbid causes, whose presence, where the predisposition prevails, may lead to a serous inflammation of the tissues of the brain, but which do not form, in any sense, parts of the disease itself; since, under every degree of them, they are so frequently remediable, by means which are alone available, for the removal of their distant and sympathetic cause."
Of Hydrothorax, Dr. Ayre very justly remarks, that, as its name imports and as defined by Nosologists, it consists of symptoms, which strictly speaking, pertain only remotely to the true disease—arising, as they do, from a certain disturbance given to the lungs, by the pressure of water upon them. They are only the symptoms, therefore, of the effusion, and as the excitement sometimes terminates with the occurrence of the serous discharge, its existence, in many cases, is discoverable only by its effects—there existing no signs, which clearly point out the presence of that state, previous to the appearance of the effusion; and what are usually called, by writers on the subject, premonitory symptoms, being only those of an inferior degree of the effusion which has already commenced.
Like hydrocephalus, hydrothorax may be idiopathic or symptomatic; and proceed from a local or general cause—the nature of the inflammation being the same in both cases. It may likewise be divided into an acute and chronic form. When the disease is symptomatic, and arises from a local cause, it is generally chronic. When it arises secondarily from a disease of the lungs, our author thinks, that
"The mode by which this state is induced in the serous membranes, is by the chronic inflammation that exists in the diseased organ extending to them; and not by the same form of inflammation being set up in them, by a certain sympathy or consent of parts, which, from a loose analogy, has been thought to subsist between similar structures."
All diseases of the thoracic organs, are not equally prone to occasion effusion; some of these also, are only dangerous to life, in proportion to their disposition in occasioning such an effusion; whilst in other cases, if it occurs at all, the effusion is only the sequel of a disease essentially fatal.
"To distinguish between these two conditions, is a desideratum pathology. Modern writers on pathological anatomy have prosecuted with considerable zeal and ability, their researches into the nature of the diseases of the organs within the chest, but they have done but little towards elucidating the true relation, which subsists between the diseases of the several viscera, and the serous effusions which take place into their cavities; for, by limiting their views to the disease which the post mortem examination exhibited, they have overlooked those intermediate actions or states of excitement which connect the organic disease with such effusions."
Whenever the excitement, producing hydrothorax, is idiopathic and independent of an organic disease of the lungs, heart, &c. its remote causes may be either of a general or local kind; and are the same which produce, when applied in a higher degree, or under different states of the system, the other forms of inflammation. The effusion may take place in those cases in which, the individual being predisposed, the inflammation, owing to some peculiarity in the cause, does not reach beyond its lowest grade; or in those in which the inflammation being high, and treated too late, or by insufficient means, a chronic form succeeds to the acute one, which may produce a watery effusion; or some structural disease remains and eventually becomes a cause of the effusion. The occurrence of this effect, in those latter cases, is sometimes attributed to a debility, resulting from the large depletion required in consequence of the severity of the previous inflammation.
"That such opinions, however, are founded in error, may be shown from this, that the effusion, thus imputed to debility, does not occur sometimes, until some weeks or months after the period when the bleeding was employed; and although the debility is confessedly of a general kind, yet the effusion is local, and is precisely in the very cavity where the disease existed, which required the unjustly condemned evacuations. The truth of the matter is, that in such cases, either the depletory means have been employed in an insufficient degree, or too late." "The imperfect recovery of such patients from their first attack, and, which is attributed to the depletion, arises from the disease which is left by it, and to the injudicious means, perhaps, that are employed by the too anxious attendants, with the view of restoring the strength."
Among the ordinary predisposing and exciting causes of the inflammation which produces hydrothorax, Dr. A. mentions a certain congestive or plethoric state of the circulation, which is brought on in some persons of particular habits, by indulging in the pleasures of the table, and taking little exercise. These cases are analogous to those occurring in the brain, and giving rise, by rupture, to a sanguineous apoplexy, or, by arterial reaction, inducing an effusion of serum.