PLEURAL FLUID The fluid has the same general characteristics as peritoneal fluid. It as a rule contains more proteids than the peritoneal fluid. It does not readily coagulate spontaneously, unless pleurisy be the cause of the exudation. A few more analytical data, in addition to those which have been already given, may be added as illustrations to the following propositions. (1) In hydrothorax, the total percentage of proteid is much lower than in cases of plowisy: the amount of fibrinogen as estimated by the weight of fibrin formed1 is also less in the fluid of hydrothorax. The following numbers are obtained from analyses of my own : (2) In hydrothorax, as in ascites, the liquid removed by successive tappings remains fairly constant in composition.2 Sugar seems to be fairly constantly present in pleuritic fluid, as in other forms of lymph. In 17 specimens examined by H. Eichhorst 3 10 contained small quantities of sugar. Exceptional forms of pleuritic effusion are sometimes found; some In the case of the liquid of hydrothorax fibrin may be formed by adding serum- or fibrin-ferment to the liquid. The fluid in chronic pleurisy closely resembles that of hydrothorax (C. Méhu, Bulletin Méd. du Nord, 1872). The example selected is an analysis by C. Schmidt. It and others will be found on pp. 602-3 of Hoppe-Seyler's Physiol. Chemie. 3 Zeitschrift f. klin. Med. iii, 537. are associated with carcinomatous or sarcomatous tumours, and the cells characteristic of these growths may be found in the pleural liquid, in addition to the usual leucocytes. In other cases hæmorrhage may occur into the pleura. In one case of hæmorrhagic pleurisy,' I found a large amount of cholesterin floating about in a crystalline form in the liquid. In another case (not hæmorrhagic) there were large corpuscles like Gluge's inflammatory corpuscles in large numbers, in addition to leucocytes. Cases of chylous pleurisy have also been described.3 PERICARDIAL FLUID This fluid is not so often removed from the human subject in cases of disease when it is present in excess, as in other forms of dropsy, because of the greater danger attending the operation. It is stated to contain a larger quantity of fibrinogen than other transudations, and Kühne found that it contains 0.879 to 2.468 per cent. of proteids. Dr. Friend has made under my superintendence the following analyses of the pericardial fluid of the horse removed after death. It is interesting to note that the pericardial fluid of the tortoise, which I have examined, exhibits precisely the same characters and properties as that of the mammalian animals. Chylous effusions into the pericardium may occur, as in the case of the other serous sacs; a case is recorded by K. Hasebroek, and it may be useful to compare the analysis of the fluid he obtained with Under Dr. Ringer's charge, Univ. Coll. Hosp. "Corpuscles three or four times the size of white blood corpuscles, containing numerous fat granules. 3 For the analysis of one see Hoppe-Seyler's Physiol. Chem. p. 596. Zeit. physiol. Chem. xii. 289. those of non-chylous pericardial fluid as recorded by previous observers. The chylous fluid will be seen to contain a greater amount both of proteids and extractives than ordinary pericardial fluid 50 per cent. of the extractives consisted of fat. more than This fluid with the preceding (pericardial fluid) is interesting historically; these fluids having been very largely employed in the course of experiments on the coagulation of the blood (see p. 243). It is contained in the tunica vaginalis, originally a part of the peritoneum, and is itself almost exactly like the peritoneal fluid. It resembles the peritoneal fluid and other forms of lymph in reaction, colour, and constituents. It does not as a rule clot spontaneously, unless mixed with blood or serum, or containing an excess of leucocytes from inflammation. Its specific gravity varies from 1016 to 1022; the amount of proteid present also varies very much. The following is the mean of 17 analyses made by Hammarsten :4 There are cases of hydrocele which differ from the ordinary fluid; some are viscous from the presence of metalbumin and paralbumin (see Ovarian Fluid); some contain excess of cholesterin; and others are chylous. The cases of chylous hydrocele are sometimes associated with 1 Lehrbuch, p. 401. 3 Physiol. Chemie, p. 605. 2 Arch. f. pathol. Anat. vii. 334. * Quoted from Hoppe-Seyler's Physiol. Chemie, p. 606 (Hammarsten's original paper s in Swedish). Other analyses by Hoppe-Seyler will be found on the same page. 5 R. Devillard, Bull. soc. chim. xlii. 617. chyluria (chylous urine); and chyluria is produced by the presence of the hæmatozoon Filaria Sanguinis Hominis in the blood (see Urine). Lymph tumours and tumours filled with chyle are very common in the scrotum and its neighbourhood in cases of chyluria, and these may discharge their contents from the surface of the skin.1 Other cases of chylous hydrocele may however occur, which seem to be produced like chylous ascites by the rupture of lacteals. I have examined one such case; it was a fluid obtained from a case of otherwise ordinary hydrocele, which was shown to the Pathological Society by Mr. S. G. Shattock.2 THE FLUID OF SUBCUTANEOUS EDEMA This fluid is poorest of all the dropsical fluids in proteid constituents; otherwise it resembles them very closely. Some analyses have already been given of this fluid, in the comparisons that we have drawn between it and other effusions; the following are some estimations of the proteid constituents which I have made. In all these cases the fluid which drained away first, coagulated spontaneously on standing; this was due to a slight admixture with blood. The fluid collected after hæmorrhage had ceased did not coagulate spontaneously, but on adding blood or serum to it, a small quantity of fibrin was in all cases obtainable. A. Rosenbach has made a special investigation whether sugar is present or not, and he finds that it is nearly constantly present in oedema fluid in small quantities. Blister fluid.This fluid has the same relation to œdema fluid, as 1 Analyses of such fluids will be found in Hoppe-Seyler's Physiol. Chem. pp. 608–9. The case was one tapped by Sir Henry Thompson, see Trans. Path. Society, XXXV. 250. Mr. Shattock informs me he has since seen a case similar to that which I analysed for him. A. Rosenbach, Breslauer ärztl. Zeit. 1885. No. 5. that of peritonitis or pleuritis to that of simple pressure dropsies into the serous cavities. It contains a large number of leucocytes, coagulates spontaneously when drawn, has a higher specific gravity (1018 or more), and a larger percentage of proteids, as is seen by boiling it, when it becomes almost solid from the heat-coagulum produced. In cases of gout, blister fluid like the blood plasma contains excess of urates, and the method of examining it for uric acid, as originally suggested by Garrod, has been already described (p. 252). THE AQUEOUS HUMOUR The anterior chamber of the eye is essentially a lymph space, and the fluid in it, the aqueous humour, is essentially lymph; but lymph which contains a very small proportion of proteid constituents. The amount of aqueous humour is directly dependent on the blood pressure (Chavvas).1 Lohmeyer2 analysed the aqueous humour of the calf, and the following are his results in parts per 1000: The aqueous humour either does not coagulate spontaneously, or clots very slowly; it contains in health no formed elements. As in other forms of lymph, however, a clot of fibrin is formed on the addition of serum. The proteids are the same in kind as in blood plasma and lymph generally, viz. fibrinogen, serum-globulin, and serumalbumin.3 Kuhn finds among the extractives that a reducing substance like sugar is constantly present in the aqueous humour of the ox and rabbit; the percentage of this substance reckoned as dextrose, present in the aqueous humour of the ox, is 0·03-0.04. This substance is not sugar, as it will not undergo the alcoholic fermentation (Gruenhagen).5 Urea and sarcolactic acid (Gruenhagen) are also present in small quantities. 1 Chavvas, Pflüger's Archiv, xvi. 148. 2 See Gorup-Besanez, Lehrbuch, 4th edit. 1878, p. 401. 5 Gruenhagen, ibid. xliii. 377. |