‘Sending your blood to the cleaner’s is a modern medical miracle. A device called an “artificial kidney” makes it all possible.’ So states an article gleaned from a 1951 issue of Popular Mechanics magazine (1). Kidney dialysis has come a long way since the first practical applications of over a half century ago. Today thousands of kidney patients routinely undergo dialysis while watching TV, reading books, playing video games, or other socializing. This is a far cry from earlier treatments in a hospital operating room environment.
The evolution of treatment of kidney issues that have led to the modern kidney dialysis machine has its roots in antiquity. From the early Roman Empire through the Middle Ages and up to the early days of our own country, “blood diseases” were usually addressed by hot baths, sweating therapies, blood letting and enemas (2). It wasn’t until the advent of modern scientific inquiry that the foundations for modern treatment of kidney failure occurred.
The treatment of kidney issues involves the principle of osmosis. Osmosis is a process by which fluid passes through a semi-permeable membrane separating dissolved substances. This is similar in principle to a strainer into which a mixture of sand and gravel is introduced. The size of the mesh will allow the finer particles of sand to pass through leaving behind the larger pieces of gravel. This principle allows toxins to be separated from blood.
The first scientific investigations of this process were done by a number of scientists beginning in the 1700’s. These investigations lead to the development of hemodialysis, or the separation of toxins from the blood. One of the early problems involving hemodialysis was the problem of blood clotting between the time it left the patient and it returned. Hirudin was an early substance that would temporarily prevent blood clotting, but problems of allergic reactions lead to the use of the current drug of choice Heparin.
The first experimental dialysis treatments involving humans occurred in Europe in 1924. But it was not until the 1940’s that enough scientific data had been gathered to begin the first clinical treatment trials with the first types of dialysis machines. Several years of patient treatments were accomplished before the technology was transported to the United States for further development. The advancements were using during the Korean conflict resulting in a reduced mortality rates for soldiers with kidney injuries.
In the late 1940’s, dialyzer membranes were improved to allow ultra-filtration, or the removal of excess body fluid. Improvement for the dialysis machines included passing the dialysis solution through a series of membranes greatly improving the efficiency. Later, the series of membranes was replaced by the capillary tube technology and then the hollow-fiber dialyzers of today. This and other research improved the filtration efficiency (4).
In spite of the technological advances in the improvement of the blood filtration process, there remained a fundamental problem of delivering enough of the patient’s blood to the dialyzer. Early methods used a glass tube inserted into the patient’s veins to deliver blood to the dialyzer. There were problems with the tube remaining in place long enough for effective treatment to occur. In 1966, a major breakthrough occurred with the first fistula being created. The fistula is the result of a procedure that partially attaches an artery to a vein to pressurize the vein from which the patient’s blood will be obtained for the filtration process.
Modern dialysis machines have evolved from the early cumbersome and inefficient devices to those with modern electronics and programmable features to allow the most efficient dialysis for the patient (3). Currently, we have reached a point where adequate treatment methods and technologies are available to all who may need it. As hemodialysis treatments have undergone vast improvement, more data has been gathered to further cause improvements in methods.
However, regardless of the high quality results of hemodialysis, which has resulted from decades of research and development, it still is dependent on the patient receiving the treatment properly. Both patient and doctor play a pivotal role in the improvement of the patient’s condition. The doctor receives patient treatment information obtained by the dialysis machine during treatment and then prescribes changes in both the treatment itself as well as medications. The patient has a responsibility for his or her own well-being by adhering to the prescribed routine including keeping dialysis appointments, obtaining the appropriate amount of time on the dialysis machine, following dietary restrictions, and taking medications both on time and in the proper dosage. A challenge indeed, but a necessary one.
(1) — http://www.fmc-ag.com/262.htm
(2) — http://books.google.com/books?id=ZyEDAAAAMBAJ&pg=PA103#v=onepage&q&f=true
(3) — http://www.freepatentsonline.com/5326476.html
(4) — http://www.ncbi.nlm.nih.gov/pubmed/9573587