Innovations in peritoneal dialysis fluid: biocompatible formulations and expanded therapeutic applications.

Peritoneal dialysis (PD) is a critical renal replacement therapy for end-stage kidney disease. However, its adoption remains limited, partly due to peritoneal fibrosis and metabolic complications induced by conventional glucose-based peritoneal dialysis fluid (PDF), the primary complications in PD patients and the leading cause of technique failure. This review outlines three innovative approaches to overcome these limitations: (1) novel biocompatible osmotic agents (L-carnitine can improve the metabolism of the peritoneum, and hyperbranched polyglycerol provides sustained ultrafiltration with dual peritoneal/renal protection), (2) advanced biocompatible buffers (citrate and pyruvate), and (3) peritoneal protectants (glycosaminoglycans and molecular hydrogen) that collectively mitigate fibrosis while protecting membrane function. These developments indicate a future direction for biocompatible PDF: integrating dual or triple protective functions of "osmotic agents + buffers + additives" synergy-optimizing hybrid formulations and accelerating clinical translation. Furthermore, we explored the emerging role of PD in refractory heart failure, where specialized PDF and steady-concentration protocols enhanced ultrafiltration efficiency. These advances address volume overload in cardiorenal syndrome, expanding PD's therapeutic scope of PD to systemic conditions such as heart failure.