Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis

The aim was to evaluate plasma proteins during continuous ambulatory peritoneal dialysis (CAPD) in relation to dialysis losses, membrane permeability, renal insufficiency, and time on CAPD. Ten male patients, established on CAPD for at least 14 months, were studied every 8 weeks for 56 weeks. Blood and dialysate from the morning exchange were analysed for urea, creatinine, and 7 proteins, and used to calculate dialysate to plasma concentration ratios (DIP). These ratios were not significantly changed suggesting that permeability remained constant. However, there was a trend for β2-microglobulin, creatinine, and urea to increase progressively. After 56 weeks, β2-microglobulin had increased from 27.9 to 31.3 mglL (p < 0.05) and creatinine 1006 to 1099 μmoLIL (p < 0.05) and both correlated with time on CAPD (p < 0.001). Plasma α1-acid glycoprotein, albumin, transferrin, IgG, IgA, and complement C3 were not significantly changed, although IgA and complement C3 were each negatively correlated with time on CAPD (r = −0.70 and −0.67, respectively), creatinine (r = 0.51 and −0.54), and urea (r = −0.61 and −0.61) (p < 0.001 for all). It is concluded that increases in β2-microglobulin, creatinine, and urea are not due to loss of membrane permeability but reflect a slight increase in uraemia. Long-term decreases in immunological proteins may be caused by uraemia or progressive depletion.

Factors contributing and predisposing to peritonitis were studied retrospectively in 83 children treated with continuous ambulatory (CAPD) or continuous cycling peritoneal dialysis (CCPD) from 1978 to 1988. Recurrent peritonitis was the most frequent complication and the major reason for peritoneal dialysis failure. Fifty patients had 171 episodes of peritonitis during the ten years and 33 remained peritonitis -free. The duration of dialysis was significantly shorter in the peritonitis-free group. The incidence of peritonitis was lower with CCPD than with CAPD. Leucopenia was not a predisposing factor nor was blood leucocytosis helpful in diagnosing peritonitis. Serum IgG was low in 33% of patients with episodes of peritonitis, but there was no correlation or predictive value in this finding. The C3 component of complement was relatively lower than the C4 but both components were usually in the normal range. Serum albumin was low in all patients, but lower in those with peritonitis episodes. Age, sex, primary disease, diapers, pyelostomies, dialysis training, and living conditions were not significantly associated risk factors. Sterile dressings gave no benefit over the shower technique. Patient noncompliance, upper respiratory tract infection, skin infections, and dental treatment were potential risk factors. However, peritonitis seemed to be distributed randomly among the patients.

Four patients on continuous ambulatory peritoneal dialysis (CAPD) developed large, symptomatic pleural effusions after commencing peritoneal dialysis. Pleuroperitoneal fistula in each case was diagnosed by the presence of a high glucose content in pleural fluid, with a normal corresponding blood sugar, and was confirmed by isotope or contrast peritoneography. Two patients had their effusions drained percutaneously, and then underwent pleural sclerosis with intracavitary tetracycline. Two patients had a thoracotomy performed, of which no fistula was identified in one case, and the other patient underwent pleurectomy. All four patients successfully recommenced CAPD several weeks after therapy, without recurrence of effusions. We conclude that pleuroperitoneal connections associated with CAPD do not mandate cessation of peritoneal dialysis and conversion to maintenance haemodialysis. Definitive diagnosis requires aspiration of pleural effusions for glucose estimation. Contrast or isotopic peritoneography is helpful in localising the fistula, but in our experience did not alter management. Simple sclerotherapy is effective and avoids the need for a formal thoracotomy.

A survey of the National CAPD Registry population was conducted to assess the distribution of hematocrit levels in a large group of peritoneal dialysis patients, to characterize the anemia of the population, and identify factors which relate to variation in hematocrit levels. A random sample of 812 patients was selected from the Registry population. Information was provided on 608 patients. Characteristics of sampled patients were similar to the Registry population as a whole. The mean hematocrit level in this cohort was 29.4% and the median was 29%. Recent peritonitis, time on CAPD, folate therapy, androgen therapy, and iron therapy had no obvious influence on hematocrit distributions. Significantly higher hematocrits were seen in males, whites, and patients with polycystic kidney disease. Significantly lower hematocrits were seen in surgically anephric patients and in patients who had received transfusions 60 days before the survey. Eighty-nine percent of patients had not received a transfusion 60 days prior to the survey. Some patients, especially those with hematocrits below the median, might benefit from recombinant erythropoietin therapy.

In a recent report, the relationship between renal creatinine clearance and hematocrit in patients with renal creatinine clearances, ranging from 55 to 8 mL per min. per 1.73 square meters of body surface area, was analyzed (1). The authors of this study have performed a crosssectional analysis of the relationship of hematocrit to residual renal creatinine clearance in patients on continuous ambulatory peritoneal dialysis (CAPD). The authors of this study wanted to examine whether or not these hematocrits fall within extrapolations of the published 95% confidence limits for males and females with renal failure prior to end-stage renal disease and dialytic intervention. Authors also compare d regression intercepts at residual creatinine clearances of 0. Most of the CAPD patients had hematocrits within the upper half or above the extrapolated 95% confidence limits for the predialysis population. Within the CAPD population, there were no significant correlations of hematocrit with residual creatinine clearance at these lower ranges. The degree of scatter in the CAPD population for hematocrit values was similar to that in the predialysis population. Residual creatinine clearance appears to be a crude index of the increasing severity of multiple factors that may contribute to the anemia. CAPD appears to maintain or improve hematocrit as renal mass and function decline.

The uptake of vancomycin from the peritoneal cavity during acute episodes of peritonitis was compared to noninfected patients in 14 patients, 7 of whom had dialysis-related peritonitis. Treatment consisted of 8 hourly dialysate exchanges, followed by 4-h dwells containing 37.5 mglL of vancomycin. On day 4, serum vancomycin concentrations were 13.4 ± 4.8 mglL in the controls and 15.5 ± 6.8 mg/L in the group with peritonitis. After 180 min in the peritoneal cavity, 61% ± 13% of the infused vancomycin remained in controls and 30% ± 15% in patients with peritonitis (p < 0.05). Uptake of vancomycin from the peritoneal cavity is enhanced during episodes of peritonitis.

Amphotericin B is the drug of choice in continuous ambulatory peritoneal dialysis (CAPD) associated fungal peritonitis and is usually administered intra peritoneally. The drug is stated to be incompatible with anions. All CAPD fluids contain chloride and lactate anions. Therefore, the physical and chemical compatibility of amphotericin B with dextrose 5%, Dianeal 1.36% CAPD fluid, and Dianeal 1.36% peritoneal effluent was studied at amphotericin B concentrations of 1, 2, and 5 mg/L. Amphotericin B was most stable in Dianeal CAPD fluid. The rate of degradation was concentration dependent in dextrose 5% and peritoneal effluent. The higher the concentration, the lower the rate of degradation. After an incubation of 6 h at 37°C, no significant decomposition was found at all concentrations studied in Dianeal CAPD fluid whereas 12–18% decomposition was found in effluent. No physical incompatibility with any solution was observed.

Investigations concerning the influence of pharmacologic agents on transperitoneal water movement are predominantly undertaken in the hope that their results can help in a restoration of net ultrafiltration (UF) volume toward normal in cases with declining UF during long-term dialysis treatment. Net UF volume represents the difference between net transcapillary UF and lymphatic absorption.

The choice of a pharmacological agent for enhancing UF depends on the mechanisms responsible for net UF loss, which include: (a) early dissipation of the transperitoneal osmotic gradient; (b) decrease in the peritoneal surface area; (c) Iymphomonokine overproduction; (d) enhanced lymphatic absorption; (e) high residual volumes left in the peritoneal cavity; or (f) a combination of these factors. Leakage of dialysate to the abdominal wall sometimes occurring in peritoneally dialysed patients (1), according to a definition of net UF volume, cannot be regarded as a true UF loss.

Previous studies have found serum tobramycin concentrations greater than 8 mg1L among patients undergoing treatment for peritonitis using hourly dialysate exchanges containing 10 mg1L of tobramycin. In this study, tobramycin absorption from the peritoneal cavity was evaluated among patients treated with exchanges of 180 min. intraperitoneal duration. Six patients in each group were studied. Mass transfer coefficients [MTC (mLI min.)] were calculated for noninfected (C) and peritonitis (P) periods. The mean MTC for C was 6.5 ± 2.1 (SD) mLlmin., and for P, 18.5 ± 8.2 (SD) mLlmin. (p < 0.01). Peritonitis increased the rate of uptake from the peritoneal cavity. In these acute studies, the total dose of tobramycin delivered was small, so that serum concentrations remained less than 0.2 mglL among controls and 0.5 mglL among patients with peritonitis. Prolonged exposure to tobramycin, in association with more rapid absorption from the peritoneal cavity, may lead to serum concentrations greater than 8 mgjL.

Fifty-five adult patients (5 women, 50 men) on chronic peritoneal dialysis, mostly continuous ambulatory peritoneal dialysis (CAPD), for 2 to 155 mon were asked whether or not they wanted to have mechanical cardiopulmonary resuscitation (CPR) in case of sudden death. Thirty-five patients (65%) opted for CPR and 20 (36%) declined. Statistically, sex (although the number of women interviewed was too small for a valid sample) and duration of dialysis had no effect on choice of CPR, whereas older age, the presence of diabetes, advanced medical disability, and advanced socioeconomic disability were associated with a tendency to decline CPR. Among the 10 patients who had CPR, 5 developed flail chest, 4 had multiple rib fractures, and only 1 had no chest wall trauma from CPR. Two patients left the hospital alive. One third of the patients on chronic peritoneal dialysis do not want CPR. Advanced age, diabetes, and poor medical and socioeconomic states predispose peritoneal dialysis patients to decline CPR.