Anatomical and physiological observations (continued) / by John Struthers.

  • John Struthers
Date:
[1858?]
Catalogue details

Licence: Public Domain Mark

Credit: Anatomical and physiological observations (continued) / by John Struthers. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    large crescentic valve at its usual termination in the back of tlie early part of the brachio-cephalic trunk; the valves being generally at the mouth, but sometimes a little way within the vein. These, and valves across the occasional termination of other small veins near the junction of the subclavian and internal jugular trunks, must not be mistaken for lymjihatic valves. The thoracic duct, I have found usually to enter just at the root of the internal jugular vein, almost in the sinus of one of the internal jugular valves, though not covered by the valve, and to be without valves at its very mouth. The duct has a funhel-like opening, and when this contracts into the duct proper, the first valve or valves are seen and catch the probe. I have, however, seen very distinct valves across the mouth of the duct, though still somewhat sunk in a depression ; the upper considerably larger than the lower; not forming valves with sinuses like those of the veins, and like the succeeding valves of the duct, but more transversely placed, though still capable of closing the duct, like the two flaps of the ileo-colic valve on a small scale, but without fraena. The duct may enter divided, one near the internal jugular, the other near the subclavian valves, and in such a case I have found both lymphatic orifices to be without valves. It now remains to be seen whether, notwithstanding the obstacle ])resented by these valves, fluid will regurgitate by an opening in the external jugular vein, so as to unload the right side of the heart. With this view I performed the following experiments. A pipe was introduced into the femoral vein, and tepid water was thrown freely upwards by a syringe. The effect of this would be, to fill the venous systems of the abdomen and thorax, and the right side of the heart and pulmonary artery, as in asphyxia; and, when these parts became distended, there would be the tendency to regur- gitation upon the veins of the neck. As the experiments proceeded, we continued to throw in the fluid at the groin, and moderate force was exerted by the syringe so as to imitate the over-distended condi- tion of the veins in asphyxia. The points to be noticed were—whether the external jugular veins became distended ; if so, whether fi’om above or from below ; and whether, when the opening was made, the fluid would regurgi- tate. The subsequent dissection of the veins will be also noticed, as the result might have been influenced by variety of connection, or by position of valves.