New solutions for peritoneal dialysis in adult and pediatric patients.

The standard PD solutions used today contain physiological electrolyte profiles similar to that of interstitial fluids and are supplemented with glucose as the osmotic agent. Improvements in solution composition during the last 20 years have been largely restricted to minor changes in buffer and electrolyte levels. Newer PD solutions, on the other hand, are designed to manage comorbidities associated with patients on maintenance dialysis, to tailor the ultrafiltration profile based upon dwell time, and to better preserve peritoneal membrane function and host defenses. The evidence to date indicates that, in malnourished PD patients (children and adults), IP amino acids improve protein nutritional status, particularly if low protein intakes are a cause of the malnutrition. The availability of glucose polymers allows the clinician to complement standard glucose-based formulations with one that can provide improved ultrafiltration in both CAPD and APD patients for long dwells, and in patients experiencing ultrafiltration loss owing to a large effective peritoneal surface area. Owing to the reduced calorie and carbohydrate load, glucose polymers may also offer long-term metabolic advantages. Although the control of acid-base balance can be well managed in the vast majority of patients with a 35-40 mmol/L lactate solution, the development and clinical evaluation of bicarbonate-based solutions is underway as a result of concern over the potentially bioincompatible nature of acidic lactate formulations. To date, in vitro, ex vivo, and limited clinical studies show that such formulations, and in particular bicarbonate/lactate combinations are efficacious and well tolerated, and show improved peritoneal cell function versus conventional solutions. In conclusion, ongoing research and development has produced a new generation of PD solutions that, to various degrees, meet different criteria established for an ideal PD solution for chronic adult and pediatric patients on PD. These criteria include good clearance and ultrafiltration, supply of nutrition, iso-osmolality, physiologic pH, bicarbonate buffer, and minimal absorption of the osmotic agent. Several of the new solutions have already demonstrated clinical utility in controlled clinical trials and are commercially available in Europe. Wider clinical use will further add to our understanding of the impact of these formulations on patient outcomes.

Bicarbonate and bicarbonate/lactate peritoneal dialysis solutions for the treatment of infusion pain.

A randomized, double-blind, cross-over study was undertaken to determine the effects of novel bicarbonate (38 mM) and bicarbonate (25 mM)/lactate (15 mM) containing peritoneal dialysis (PD) solutions on infusion pain in patients who experienced inflow pain with conventional lactate (40 mM) solution. Pain was assessed using a verbal rating scale and the validated McGill Pain Questionnaire (MPQ). Eighteen patients were recruited to the study. Both novel solutions resulted in highly statistically significant reductions in inflow pain compared to the control lactate solution, as assessed with both the verbal rating scale and the MPQ. For all pain variables assessed, the bicarbonate/lactate solution was more effective than the bicarbonate solution in alleviating pain. In conclusion, both solutions reduced the infusion pain experienced with control solution, but the bicarbonate/lactate solution appears to be the most effective. In contrast to the most widespread current treatment, which is the manual injection of sodium bicarbonate, the bicarbonate/lactate solution does not have the associated increased risk of peritonitis.

Design and testing of the Baxter Integrated Disconnect Systems (IDS).

This paper describes the result of a miltidisciplinary approach to the design and evaluation of a new CAPD disconnect system: the Baxter Integrated Disconnect System (IDS). This system consists of a bag full of fresh Dianeal, an empty bag for the drainage of spent dialysate and tubings connecting the 2 in a Y fashion. With this system, the patient makes only one connection. The system is disposable. The major property that makes this unique is that all components are preassembled, and the whole system is steam-sterilized as 1 unit. In general, similar systems use different sterilization methods for the various components of the system. Those components are then assembled, under clean conditions by the manufacturer, without final sterilization of the unit. Assembly of the components is sometimes left to the patient. The concept of IDS, therefore, is unique and warrants lower rates of contamination. This system has been tested on patients for a total observation period of 765 patient months, and has proven to be simple, safe and effective. It yields a 63% probability of peritonitis-free patients at 24 months.