The Birth and Development of Continuous Ambulatory Peritoneal Dialysis.

Peritoneal dialysis has a long and tortuous history. First done in animals in the late 1800s, it became clinically practical in the early 1960s. Peritoneal access was first achieved by intermittent abdominal puncture, and then through the development of a 'permanent access' when Silastic became available. The early design is appropriately named for Dr. Henry Tenckhoff. Successful peritoneal dialysis was performed intermittently with infusion of 2 liters of balanced fluid followed by a dwell time of 30-45 min, which in turn was followed by drainage and new infusion. The procedure was used almost exclusively in the intensive care setting but failed to achieve success when applied on a long-term basis. The new concept of extending the dwell time of the dialysis fluid to allow equilibration between an acceptable blood level of urea and the level of urea in the dialysis fluid remarkably reduced the fluid volume required to control uremic toxins and symptoms. This change also allowed the patient to be disconnected from all devices and freely move about as dialysis took place. It was concluded that an acceptable blood level of urea nitrogen was 70 mg %. Equilibration with dialysis fluid, five 2-liter exchanges for 10 liters per day, would allow the removal of 7,000 mg of urea, the average quantity generated on a diet of a 70-kg person eating 1 g of protein per kg of body weight per day. The procedure was originally called 'equilibrium peritoneal dialysis', but was later changed to 'continuous ambulatory peritoneal dialysis'.