To the pharmacology and physiology of veins

Numerous factors play a role in the movement of blood through the veins, the residual strength of the heart, negative pressure in the chest cavity and the right heart are those moments that create a difference in the initial and final pressure in the veins and which provide siphon phenomena in them. At the same time, we should not forget about the role played by atmospheric pressure and due to which the phenomena of the siphon (Bogomolets) are possible. Among other factors contributing to the movement of blood through the veins, it is necessary to point out the venous valves and skeletal muscle contractions (Tigerstedt, Burton-Opitz). The significance of the latter can be seen at least from the fact that when drugs are injected into the veins, the patient is often forced to alternately clench his fingers into a fist and unclench them. However, the value of muscle contractions has recently been subjected to some authors to a certain doubt. So, according to Jones Wood, muscle contractions can contribute to blood flow only if they go evenly from segment to segment; but even if this were the case in an ideal case, then even then there could be stagnation and overflow of blood of the superficial veins, which, according to the author, are not exposed to the action of the muscular press.