An Unusual Cause of Massive Intraperitoneal Bleeding in CAPD

A 73-year-old man, who had been on CAPD for two years, presented with massive intraperitoneal hemorrhage. On laparotomy the peritoneal catheter was situated in a large pouch that was lined by fibrous tissue. The hemorrhage arose from erosion of the pouch wall -an unusual cause of intraperitoneal bleeding in the CAPD patient.

Massive intraperitoneal bleeding is a rare complication of continuous ambulatory peritoneal dialysis (CAPD). Mild to moderate bleeding, which is more common in CAPD, usually is related to disintegration of small blood vessels. In most patients the bleeding is self-limited. This paper describes an unusual cause of massive bleeding in a CAPD patient.

The Durability of the Peritoneal Membrane

Severe membrane functional limitations with time on peritoneal dialysis are infrequently reported. Occasional reports where most patients were affected by peritoneal functional loss are in conflict with the good preservation of function reported by others. Such endemic distribution of structural and functional deterioration of the peritoneum should facilitate the search for etiologic factors. In the present state of ignorance it seems wise to treat infectious peritonitis promptly and aggressively, to support research in the area of membrane solution interaction and to carefully monitor the effects of chronic peritoneal dialysis on the peritoneal membrane.

The most important determinant of the success of peritoneal dialysis in providing adequate therapy for chronic renal failure is the durability of the peritoneal membrane. Dobbie et al (I) have clearly stated the magnitude and severity of the problem in the following passage: “In view of the fact that most renal dialysis centres throughout the world are now embarking on a relatively new form of treatment for chronic renal failure -continuous ambulatory peritoneal dialysis, it is perhaps ironic that so little is known structurally of the tissue on which depends a life maintaining procedure and on which so many aspirations are now based.” Our ignorance of the peritoneal architecture is surpassed only by our poor understanding of the relationships between functional and structural changes.

From the functional point of view, the peritoneal membrane includes the mesothelium which covers its free surface, the peritoneal interstitium, probably composed of an aqueous network bathing gels of mucosaccharides and collagen, and the microcirculation. Extensive research has been recently initiated to study the role of each of these components in transperitoneal transport and ultrafiltration and the effect of chemical and mechanical injury on the peritoneal membrane (1,2). The interest in investigating the factors responsible for altered states of solute and water transport during peritoneal dialysis has been stimulated by alanning reports suggesting functional deterioration of the peritoneal membrane system during chronic dialysis (3,4).

Chyloperitoneum: A Rare Complication of Peritoneal Dialysis

An eight-year old girl with extensive burns and aminoglycoside-induced acute renal failure was treated with peritoneal dialysis. She developed chyloperitoneum after medical insertion of a Tenckhoff catheter. Conservative dietary treatment with medium-chain triglycerides, supplemented by parenteral hyperalimentation and temporary cessation of the peritoneal dialysis allowed the chylous fistula to heal, without the need for surgical intervention.

Leakage of milky chyle into the peritoneal cavity (chyloperitoneum or chylous ascites) is a rare clinical entity. Generally it is due to trauma or obstruction of the lymphatic system. It has been observed in adults with intra-abdominal malignancies and/or inflammations and in children with congenital malformations of the abdominal lymphatics (I). Chyloperitoneum also has been seen after abdominal trauma, including surgery (1–5); chyloperitoneum has been mentioned before as a complication of peritoneal dialysis but no details have been provided (1,6). This paper will report the occurrence and treatment of chyloperitoneum in an eight-year-old child undergoing peritoneal dialysis for acute renal failure.

Peritoneal Solute Clearances after four Years of Continuous Ambulatory Peritoneal Dialysis (CAPD)

In order to evaluate peritoneal membrane function and responsiveness of peritoneal microcirculation to vasoactive agents in long-term continuous ambulatory peritoneal dialysis (CAPD) patients, we studied peritoneal clearances of urea (Curea) and creatinine (Ccr), protein concentrations in drained dialysate (D PC), peritoneal glucose absorption (% GA), and drained dialysate volume ( VD) before and after nitroprusside (NP) addition to dialysis solution in 17 long-term CAPD patients (mean duration of CAPD: 52 months) and the results were compared to those of 18 patients who were just trained for CAPD (mean duration: 0.6 month).

There were no differences in the control (without NP) Curea, Ccr, D PC, %GA, and VD between the new and long-term CAPD patients. Curea, Ccr, and D PC increased significantly with NP in both new and long-term patients. Curea and Ccr with NP were not different between the new and long-term patients but D PC with NP was significantly lower in the long-term CAPD patients.

The results of this study suggest that peritoneal solute clearances and the responsiveness of peritoneal microcirculation to NP remain unchanged after four years of CAPD, despite recurrent episodes of peritonitis.

Peritoneal Sclerosis in Continuous Ambulatory Peritoneal Dialysis Patients Dialyzed Exclusively with Lactate-Buffered Dialysate

Peritoneal sclerosis occurred in two patients treated by continuous ambulatory peritoneal dialysis (CAPD) using only lactate-buffered dialysate. Both patients had recurrent peritonitis and the second patient had multiple, minor abdominal operations. Patients receiving lactate-buffered CAPD are not immune from peritoneal sclerosis. Recurrent peritonitis and repeated abdominal surgery might be important causative factors.

An autopsy study of the peritoneal cavity from patients on continuous ambulatory peritoneal dialysis

Sixteen autopsies were performed on patients aged 56 +/- 15 (SD) years who were on continuous ambulatory peritoneal dialysis (CAPD) for 834 +/- 766 (SD) days. Lactate-buffered dialysate and povidone-iodine antiseptic were used in all cases. Multiple peritoneal sections were taken to evaluate peritoneal membrane thickening, inflammation, neovascularization, fibrosis, and adhesions. Peritoneal thickening, inflammation, or adhesions were not related to sex, race, or etiology of renal failure. Time on dialysis was also not a direct determinant of peritoneal adhesions or neovascularization. Peritonitis episodes correlated with chronic peritoneal serosal changes. This study supports the hypothesis that peritoneal alterations in patients on CAPD are related to episodes of peritonitis.

Acute changes in peritoneal morphology and transport properties with infectious peritonitis and mechanical injury

Peritoneal clearance studies were performed in rats undergoing acute peritoneal dialysis. Some of these animals were then exposed to laparotomy and mechanical drying of the peritoneum. Peritoneal clearance studies were repeated at intervals up to 11 days. Another group of rats was placed on daily peritoneal dialysis and allowed to spontaneously develop peritonitis which was not treated. These rats underwent peritoneal transport studies at differing durations of infection. In all groups, animals were sacrificed at the time of the last transport studies for morphological assessment of the peritoneum by light microscopy, scanning electron microscopy, and transmission electron microscopy. The results showed similar decreases in drainage volume and increases in glucose absorption and protein losses with both infection and drying. Both types of injury resulted in extensive mesothelial structural changes. While drying caused mainly denudation of the mesothelial surface, infectious peritonitis was associated with separation of mesothelial cells, and the appearance of numerous white blood cells between and on mesothelial cells. Exposure to peritoneal dialysis alone had no obvious effects on anatomy. Although changes in the peritoneal microcirculation and deeper structures cannot be excluded as contributing to peritoneal transport alterations, the findings suggest that alterations of mesothelium might explain some of the changes in peritoneal transport properties under the conditions of these studies.