Effects of Bicarbonate/Lactate Dialysis Solution on the Inflammatory Response of Spontaneous Peritonitis in Rats Undergoing Chronic Peritoneal Dialysis

Abstract

Background: We evaluated the incidence of spontaneous peritonitis as well as the local inflammatory response and macroscopic changes in the peritoneum during the use of a bicarbonate/lactate-buffered (P) solution in comparison to conventional (D) solutions in rats on chronic peritoneal dialysis. Methods: Sixty-three male Wistar rats were implanted with peritoneal catheters. After 7 days, the animals were randomly divided into 2 experimental groups (32 rats in D, 31 rats in P) and infused twice daily over the following 4 weeks. Results: After 14 and 23 days, rats dialyzed with D had a higher peritonitis rate than those dialyzed with P. The median number of days until peritonitis occurred was 22 days for the rats in the D group and 29 days for the rats in the P group. Spontaneously infected rats dialyzed with the D solution had higher scores for adhesion formation. Conclusions: In this animal model, dialysis with P delayed the time to the 1st infection, reduced the overall peritonitis rate and reduced peritonitis-associated peritoneal adhesion formation during chronic peritoneal dialysis.

Animal Models of Peritoneal Dialysis: Thirty Years of Our Own Experience

“…Additionally, dialysis fluid has nonphysiological composition (i.e., low pH, hypertonicity, and high-glucose concentration) which on one hand stimulates an inflammatory reaction and on the other hand may have a direct injuring effect to the peritoneum [ 57 ]. Some of the results found in experimental “short-term studies,” lasting several hours, may not be the same as those observed in patients maintained on PD for a long time [ 23 , 37 , 47 , 48 , 58 , 59 ]. We developed an experimental chronic peritoneal dialysis model for repeated dwell study in rats.…”

“…The cuff was attached to the superficial muscle layer by purse string sutures. The catheter was pulled up through a subcutaneous track up to the animal's neck and exteriorized between the ears [ 23 , 37 , 47 , 48 , 58 , 59 ]. Then 10–15 mL of peritoneal dialysis fluid was infused into the peritoneal cavity via the catheter and immediately drained.…”

“…PET was performed during a 2- or 4-hour exchange with hypertonic peritoneal dialysis solution according to the protocol used in our lab [ 27 , 30 , 37 , 48 ]. Under ether anesthesia, a blood sample was drawn from the tail vein in each rat.…”

“…We consider that repeated dwell studies with drainage might improve the understanding of changes in transperitoneal permeability during peritoneal dialysis [ 3 , 27 , 60 ]. The advantage of this model in relation to other peritoneal dialysis animal models is the ability to conduct peritoneal dialysis with fluid exchanges where the fluid drainage is conducive to effluent cell analysis and active substance concentration measurements [ 3 , 27 , 30 , 37 , 38 , 40 , 58 ]. It is of importance to evaluate, in a continuous fashion, transport across the membrane during the study and perform histopathological tissue assessment at the end of the experiment [ 38 , 40 , 42 ].…”

“…In our lab we established an acute and chronic PD model in nonuremic rats and mouse [ 3 , 19 , 20 , 23 , 25 – 36 ]. This model has been modified to evaluate the different aspects of peritoneal dialysis [ 3 , 19 , 20 , 37 – 48 ]. The main objective of our research was to evaluate the usefulness of the peritoneal dialysis animal model as a means to evaluate the changes taking place during the treatment with peritoneal dialysis and correlate these experimental results with those in a clinical setting.…”