A biennial retrospect of medicine, surgery, and their allied sciences, for 1867-8 / edited by H. Power [and others] for the New Sydenham Society.

Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: A biennial retrospect of medicine, surgery, and their allied sciences, for 1867-8 / edited by H. Power [and others] for the New Sydenham Society. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    turbing the general circulation of the body. In the liver similar anastomoses may be seen between the vena portae and the subhepatic veins ; and M. Sucquet* has shown that similar anastomoses exist in man between the arteries and the veins of the peripheric circulatory system. Aron- heimf notices that the addition of i per cent, of common salt, or chloride of potassium, retards, whilst 3 per cent, accelerates, the movement of the blood through the vessels ; in the latter case because it causes contraction of the blood-corpuscles. No change was effected on fluids free from cor- puscles by such addition. MM. Ainser and LoheJ made some experiments to determine the in- fluence of irritation and of section of the vagi on the rapidity of the circulation in the dog. They found that, under normal conditions, the duration of the circuit was above 18 or 19 seconds, the heart beating about 24 or 23 times. Excitation of the vagus occasioned reduction of the frequency of the pulse and marked prolongation of the period in which the circuit was performed, occupying in one or two instances as long as 60 seconds. Section of the vagi after the lapse of a few seconds produced little effect. Chr. Loven§ has shown that by irritating the sensory nerves of a part a reflex influence can be exerted on the vaso-motor nerves, apparently of an inhibitory nature, effecting the diminution of their action, and conse- quently leading to dilatation of the vessels. Thus, if the auricular nerve in rabbits, or the dorsal nerve of the foot, be irritated, even in animals poisoned with woorara, in whom, therefore, no struggling occurred to confuse the result, the corresponding arteries—as the auricular and saphena—underwent, in the course of from 4 to 6 seconds, a sudden and extraordinary dilatation, which quickly attained its maximum, and again, a few seconds after the removal of the electrodes, completely disappeared. Coinciden.tly with this the frequency of the cardiac beats invariabty which he attributes to a reflex influence, exerted through the pueumo- gastric, since it failed to occur when these nerves were divided. || Veins.—M. Jacobson^]- has given the results of a series of experiments undertaken upon sheep, with a view to determine the pressure exerted in the veins during normal respiration. They are as follows: In the left innominate vein — o-j „ right jugular + 0*2 „ right subclavian . . . . . . —7 O* I „ left jugular . . . . . 0*1 „ left subclavian . . . . . — o*6 In a brachial vein, opening into the last the origin of the innominate vein . . I* In the external facial vein • + .V ,, internal „ • + S'2 „ brachial vein • + 4’i named, close to * ‘ De la Circulation dans laTete et dans les Membres de l’Homme,’ i860, f ‘ Hoppe-Seyler’s Med.-Chem. Untersucli.,’ Heft ii, 265. X ‘ Heiile und Meissner’s Zeits. f. rat. Med.,’ 1868, xxxi, p. 33. § ‘ Ludwig’s Arbeit aus der Physiolog. Anstalt zu Leipzig,’ 1867, p. 1. || For a good account of the sphygraograph and its application to pathology, the reader is referred to the little work of Dr. ilurdon Sanderson, Lond., 1867.