The new formula for cell supply in tissues with the help of blood circulation is a fact. Let's talk about the consequences of this

Abstract

For more than a century, circulatory physiologists have been working on their field by cultivating their own knowledge and creating a framework of their own principles. Separatism in science, however, has a bad prognosis because the laws of nature are the same in all disciplines. After the misguided development in this period, there is an urgent need to reorganise the Theory of Microcirculation. I. LAW AND ORDER IN THE THEORY OF MIKROZIRKULATION: It is important to know that in fluid mechanics one cannot simply write equations as one pleases. There is „law and order“ in science, especially in this sense that the laws of nature and the peculiarities of fluid mechanics must be observed in the theory of microcirculation in tissue also. When one writes an equation, that equation belongs only to a specific tissue model and, conversely, to a specific tissue model belongs 100% to a single equation specific to that model. In this context, the Starling equation only applies to interstitials with infinite compliance. II. METHOD: A porous tube like the blood capillary must be calculated correctly by approximating the capillary length slice by slice by "finite elements" to an equivalent circuit diagram. III. RESULTS: The results are surprising because a) In the closed interstitium the porous capillary automatically finds an equilibrium for different values of blood pressure (PCA-PCV) over the whole capillary b) The pressure at the capillary beginning PCA, the pressure at the capillary end PCV, the capillary conductance Kfμ and the colloid osmotic pressure difference Δπ=COP give a new relationship for the local flow through the capillary wall Jvμ: Jvμ=Mfμ(PCA -PCV)+Σ njμ.Δπjμ. (j=1 to N) (1) In this equation, the interstitial hydraulic pressure Pi=IFP is missing because it is derived from the pressure PCA and Pi is not an active parameter. However, Pi is reduced by the amount COP=Δπ. In the state of equilibrium the second summand results to zero, so that the local current Jvμ through the capillary wall is independent of the COP=Δπ: Jvμ=Mfμ(PCA-PCV), (2) Piμ=Nfμ(PCA-PCV)-Δπ. (3) IV. CONCLUSIONS: The colloid osmotic pressure of the blood COP does not appear in the tissues as an opponent of the blood pressure, rather the COP supports the supply of the cells. In the lungs, COP enables respiration; in the whole body, the COP effect against the development of oedema is of extraordinary importance. Since the early days of circulatory physiology 125 years ago, circulatory physiologists have believed that this function of COP is possible because, according to Starling's equation, COP as an opponent of blood pressure Pc would reduce filtration into the interstitium. However, COP also enables these effects as an opponent of interstitial fluid pressure (IFP). To understand this, it is first important to understand the situation with IFP. The IFP is a passive parameter and arises from the summative effect of the blood pressure Pc and the COP=(πc-πi), see equation (3). According to the definition Pressure= Force / Area, (4) there is no independent force in the interstitium that could cause spontaneous IFP. In the previous theory of microcirculation, the wrong tissue approximation was used, the wrong equation was calculated, and there was an irrational idea of how interstitial fluid pressure (IFP) arises and how it must be measured. They also used the wrong method to determine CFC. How could one arrive at a correct result in this case? The damage that the Starling teaching has done in 125 years cannot be overlooked. No Fundings. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.