Relation Between Heart And Kidneys
( Originally Published 1921 )
The relation between the heart and the kidneys is intimate. When the heart is unable to circulate the blood properly, the kidneys are either badly supplied with blood or the blood stagnates in the region of the kidneys and causes congestion. Under these circumstances, the kidneys do not act well, and the whole system is poisoned by retention of the waste products of life that should be cast off. In this case the kidneys are damaged by the heart. This occurs in valvular disease and when the heart's power is lost for any reason.
Sometimes, however, things work in the opposite direction, and the kidneys become diseased, either by an habitual excess of food, by poison from some infectious disease, or by some chemical poison. When the kidneys are inflamed scars result, and the kidneys finally become contracted and can not do their work. Under the latter circumstances, there is a demand for a high blood pressure on the part of the body because it is only by keeping up a high blood pressure that the damaged kidneys can be made to act.1 This demand for high blood pressure puts extra work on the heart, which becomes enlarged by increase of its muscular tissue, and there is hypertrophy of the heart.
The relation between the heart and the kidneys is so intimate that it is fair to call the kidneys organs of circulation, their office being to remove from the circulation such materials as correspond to the ashes of a fire, in other words, the waste products of combustion.
A fire is the chemical union of oxygen with some substance that is capable of being burned, or, in other words, of being oxydized so rapidly as to give forth heat and light. The same process goes on slowly in the body when the oxygen of the air is absorbed into the blood through the lungs, unites with various sub-stances, and generates heat and other forces.
The most abundant products of an ordinary fire are carbonic acid and water; these are carried up the chimney in the form of smoke and steam. In an ordinary fire the waste of the fire consists of ashes, but in the human body, after the carbonic acid and some of the water has been carried off through the lungs, there remain much more complicated products which are dissolved in the blood until they are excreted by the kidneys.
Another interesting fact is that the same poi-sons, generated in the intestinal tract, that injure the heart may also injure the kidneys. It is my own observation that those who for a long period of time have shown reactions of intestinal putrefaction develop albumen in the urine and some in jury to the heart. It is also well known that some persons with heart disease die because the kidneys fail to act sufficiently, and that patients with kidney disease generally die through failure of the enlarged heart to do its work. So it behooves all sufferers from heart disease to pay particular attention to all those things that are good for the kidneys and to avoid all those things that may be a strain upon them and cause them injury.
The nurse should pay particular attention to the quantity of fluid excreted by the kidneys, and should also measure the quantities of fluids taken by the patient, since a proper balance between the two ought to be maintained. The kidneys should be particularly watched after the administration of remedies that are expected to affect their activity.