Peritoneal dialysis in infants and young children

Although end-stage renal disease is rare in infants and young children, its development can be associated with significant morbidity and mortality and only through the provision of experienced, multidisciplinary care can a favorable outcome be anticipated. Peritoneal dialysis is the renal replacement modality of choice for this age group and serves as an essential bridge until successful renal transplantation can occur. In this review, we discuss the practice of peritoneal dialysis in infants including the unique ethical and technical considerations facing pediatric nephrologists and caregivers. In addition, we review current guidelines concerning nutrition, growth, and adequacy, as well as the literature on complications and outcomes.     

Peritoneal dialysis practice in Australia and New Zealand: a call to action

Peritoneal dialysis technique survival in Australia and New Zealand is lower than in other parts of the world. More than two-thirds of technique failures are related to infective complications (predominantly peritonitis) and 'social reasons'. Practice patterns vary widely and more than one-third of peritoneal dialysis units do not meet the International Society of Peritoneal Dialysis minimum accepted peritonitis rate. In many cases, poor peritonitis outcomes reflect significant deviations from international guidelines. In this paper we propose a series of practical recommendations to improve outcomes in peritoneal dialysis patients through appropriate patient selection, prophylaxis and treatment of infectious complications, investigation of social causes of technique failure and a greater focus on patient education and clinical governance.     

Peritoneal dialysis practice in Australia and New Zealand: A call to sustain the action

This paper updates a previous ‘Call to Action’ paper (Nephrology 2011; 16: 19–29) that reviewed key outcome data for Australian and New Zealand peritoneal dialysis patients and made recommendations to improve care. Since its publication, peritonitis rates have improved significantly, although they have plateaued more recently. Peritoneal dialysis patient and technique survival in Australian and New Zealand have also improved, with a reduction in the proportion of technique failures attributed to ‘social reasons’. Despite these improvements, technique survival rates overall remain lower than in many other parts of the world. This update includes additional practical recommendations based on published evidence and emerging initiatives to further improve outcomes.     

Peritoneal dialysis catheter insertion strategies and maintenance of catheter function

It has been more than 40 years since permanent peritoneal dialysis (PD) access with the Tenckhoff catheter was first described, and despite much experimentation with catheter design and insertion techniques, access to timely and skilled PD catheter insertion remains a barrier to more widespread PD use in many centers. This article reviews different insertion techniques with a focus on both mechanical outcomes as well as logistic advantages associated with the embedded catheter and percutaneous techniques. Maintenance of catheter function is discussed with a focus on an organized and evidence-based approach to preventing and treating mechanical catheter problems.     

Peritoneal clearances with different dialysis regimens in children undergoing continuous cycling peritoneal dialysis

Peritoneal clearances and dialysate protein losses occurring in paediatric patients undergoing different continuous cycling peritoneal dialysis (CCPD) regimens have not been well defined. We, therefore, evaluated 10 children aged 15.8 +/- 2.5 (SD) years who were maintained on home peritoneal dialysis for 20.5 +/- 10 months. All patients had at least 3 months of CCPD. The patients were admitted to the Clinical Research Center for 48 hours and allocated to five different dialysis protocols. In protocol I, the frequency of exchanges was 10 per 10 hours; in Protocol II it was 5 per 10 hours; and in Protocol III it was 3 per 10 hours. Protocol II D and III D had, in addition, a daytime dwell of one-half the night-time volume. A 1.5% glucose dialysate solution was used for night-time dialysis, and 4.25% glucose dialysate solution for the daytime dwell. The mean inflow dialysate volume per exchange was 36.7 +/- 5.6 ml/kg body weight and was constant in each patient for each study protocol. BUN and creatinine clearances for each protocol were calculated and dialysate protein losses were measured. The data indicate that hourly night-time dialysis (Protocol I) provides best solute clearance. A daytime dwell further enhances the total solute clearance and should be used preferably in anuric patients. Residual urine output contributes significantly to the total solute clearance. Protein losses are maximum with low-frequency exchanges and a daytime dwell. No significant differences in the serum albumin concentrations were found during the different protocols; however, the long-term effect of the protein loss on the nutritional status of the patients requires further evaluation.     

Peritoneal dialysis catheter embedment: surgical considerations,expectations, and complications

Background

Peritoneal dialysis catheter embedment consists of implanting the catheter far in advance of anticipated need, with the external tubing buried under the skin. The catheter is externalized when initiation of dialysis is required. Details of the surgical procedure and management of associated complications are generally lacking.

Methods

A total of 84 catheters including conventional and extended catheters were embedded and externalized during the study period. Factors influencing duration of embedment, functionality upon externalization, and long-term outcomes were analyzed.

Results

Mean duration of embedment was 13.9 months (median 9.4; range .5 to 68.5). Immediate function was exhibited in 85.7% of catheters. Employing laparoscopic revision, 98.8% of embedded catheters were successfully used for peritoneal dialysis. Extended catheters and duration of embedment were important determinants of catheter functionality.

Conclusions

Catheters can be embedded for prolonged periods and still result in functional dialysis access when needed. Complications are few and easily managed.     

A ten-year single-centre experience in children on chronic peritoneal dialysis--significance of percutaneous placement of peritoneal dialysis catheters.

BACKGROUND: Chronic peritoneal dialysis (CPD) in children is an important modality of renal replacement therapy. The ideal method for inserting CPD catheters remains still controversial. Minimal invasive techniques are becoming more popular. This study was performed in order to evaluate the efficiency, the complication profile and the survey of percutaneously placed CPD catheters in children, retrospectively. METHODS: This study was carried out on 108 peritoneal catheters implanted in 93 patients (45 girls, 48 boys), aged 8.0+/-4.2 years (range: 3 months to 16 years) during the period between December 1995 and November 2005. In the study group, 32 children were transplanted, 15 were transferred to haemodialysis and 18 patients died. All catheters implanted by percutaneous route were Tenckhoff swan-neck double-cuff paediatric catheters. Placement procedure was performed in our unit by us. Statistical analysis was made by chi-square and Kaplan-Meier methods. RESULTS: During 2670 CPD months we observed a total of 108 catheter-related complications: 82 catheter infections including exit-site and/or tunnel infection (1/32.5 patient-months), 10 dislocations, six drainage problems and six kinks. The incidence of all complications was one complication every 24.72 dialysis months. Overall, the incidence of peritonitis was one episode per 18.1 patient-months. Pseudomonas spp. and Staphylococcus aureus were the two most common causes of infections. Fifteen catheters were removed due to catheter-related causes: drainage problems (six patients), catheter dislocation (three patients), omental capture (two patients) kink (two patients) and tunnel infection (two patients). The catheter survival rate was 92.4% at 1 year, 83% at 2 years and 63% at 10 years; patient survival in the 93 children was 91% at 1 year, 84% at 2 years and 48% at 10 years. Younger patients were at increased risk of exit-site and tunnel infections (P<0.05) but the difference in catheter survival time between the age groups was not significant (P>0.05). In complications, no statistical difference was observed between early and delayed catheter use groups (P>0.05). We compared the two periods (period 1, December 1995 to November 2000; period 2, December 2000 to November 2005), for complications of CPD. The risk of catheter migration was greater in period 1 than in period 2 (P=0.04). CONCLUSIONS: The percutaneous technique performed by experienced nephrologists is a reliable, safe and cost-effective method for placement of PD catheters. In our opinion, the skill for CPD catheter placement must be part of the paediatric nephrologist training.     

Peritoneal dialysis catheter infections in children after renal transplantation: choosing the time of removal

As a foreign body, the peritoneal dialysis (PD) catheter represents a potential source of infection, particularly for immunosuppressed renal transplant patients. A retrospective study was therefore undertaken to compare the risks and benefits of our policy of removing PD catheters at 3 months following renal transplant, which was established to allow for early re-initiation of dialysis. Between 1984 and 1990, 43 renal transplants were performed in 35 children who had been receiving maintenance PD. During the 1st month post transplantation, the PD catheter was used in 25 patients (58%) because of acute rejection or primary allograft non-function. Thirty-one patients were eventually discharged with functioning allografts and a PD catheter in place. Of them, 43% developed a catheter-related infection within the next 2 months, a period during which PD was not performed. Potential contributing factors included a history of catheter-related infection prior to transplantation, use of high-dose methylprednisolone to treat acute rejection, and the type of maintenance immunosuppression prescribed; conversely, the use of prophylactic antibiotics appeared to decrease this risk. This study established the potential need for the catheter during the first few weeks, but because of the infection risk of 43% by 3 months post transplantation, our protocol was revised to include catheter removal at the time of hospital discharge. From 1990 until the end of 1992, an additional 19 PD recipients underwent transplantation. In this group, catheters were used during the 1st month in 6 children (32%). Fifteen patients were discharged with a functioning allograft and only 1 patient returned to PD at 12 months post transplant. It is concluded that PD catheters represent an additional source of infection following transplantation and should be removed at the time of hospital discharge, after which the likelihood of use is low.     

Growth of children following the initiation of dialysis: a comparison of three dialysis modalities

Maintenance dialysis usually serves as an interim treatment for children with end-stage renal disease (ESRD) until transplantation can take place. Some children, however, may require dialytic support for an extended period of time. Although dialysis improves some of the problems associated with growth failure in ESRD (acidosis, uremia, calcium, and phosphorus imbalance), many children continue to grow poorly. Therefore, three different dialysis modalities, continuous ambulatory peritoneal dialysis (CAPD), cycler/intermittent peritoneal dialysis (CPD), and hemodialysis (HD), were evaluated with regard to their effects on the growth of children initiating dialysis and remaining on that modality for 6–12 months. Growth was best for children undergoing CAPD when compared with the other two modalities with regard to the following growth parameters: incremental height standard deviation score for chronological age [–0.55±2.06 vs. –1.69±1.22 for CPD (P<0.05) and –1.80±1.13 for HD (P<0.05)]; incremental height standard deviation score for bone age [–1.68±1.71 vs. –2.45±1.43 for CPD (P=NS) and –2.03±1.28 for HD (P=NS)]; change in height standard deviation score during the dialysis period [0.00±0.67 vs. –0.15±.29 for CPD (P=NS) and –0.23±.23 for HD (P=NS)]. The reasons why growth appears to be best in children receiving CAPD may be related to its metabolic benefits: lower levels of uremia, as reflected by the blood urea nitrogen [50±12 vs. 69±16 mg/dl for CPD (P<0.5) and 89±17 for HD (P<0.05)], improved metabolic acidosis, as indicated by a higher serum bicarbonate concentration [24±2 mEq/l vs. 22±2 for CPD (P<0.05) and 21±2 for HD (P<0.05)]. In addition, children undergoing CAPD receive significant supplemental calories from the glucose absorbed during dialysis. CAPD, and possibly, other types of prolonged-dwell daily peritoneal dialysis appear to be most beneficial for growth, which may be of particular importance for the smaller child undergoing dialysis while awaiting transplantation.     

Effect of peritoneal dialysis fluid composition on peritoneal area available for exchange in children.

BACKGROUND: Although conventional peritoneal dialysis fluids (PDFs), such as Dianeal, are non-physiological in composition, new PDFs including Physioneal have a more neutral pH, are at least partially buffered with bicarbonate and, most importantly, contain low concentrations of glucose degradation products (GDPs). METHODS: To evaluate the impact of new PDFs in childcare, we performed a comparative crossover study with Dianeal and Physioneal. We examined both intraperitoneal pressure (IPP), which partly reflects pain induction, and the total pore area available for exchange, which indicates the number of capillaries perfused in the peritoneal membrane at any given moment and therefore partly reflects peritoneal dialysis capacity. The IPP was determined after inflow of 1000 ml/m(2) body surface area (BSA) of dialysate (intraperitoneal volume; IPV). The steady-state unrestricted area over diffusion distance (A(0)/ triangle up x, in cm(2)/cm per 1.73 m(2) BSA) was calculated from the three-pore theory. Six children were enrolled in the study. On the first day, two consecutive peritoneal equilibration tests of 90 min each were performed using first Dianeal and then Physioneal. On the second study day, the procedure was repeated with the fluids given in the opposite order. RESULTS: The mean IPP normalized to IPV (ml/m(2)) was significantly higher for Dianeal (9.5 +/- 0.9 cm/1000 ml/m(2)) than for Physioneal (7.9 +/- 1.2 cm/1000 ml/m(2), P < 0.01). The mean A(0)/ triangle up x was 17 +/- 4% larger with Dianeal (36 095 +/- 2009 cm(2)/cm per 1.73 m(2)) than with Physioneal (31 780 +/- 2185 cm(2)/cm per 1.73 m(2), P < 0.001; based on 24 data pairs). CONCLUSIONS: These pilot study results suggest a higher biocompatibility for Physioneal than for Dianeal. Less inflow pain associated with Physioneal induced a lower IPP reflecting enhanced fill volume tolerance, and the lower A(0)/ triangle up x reflected less capillary recruitment. Taken together, these results suggest that the new more biocompatible PDFs will improve peritoneal dialysis therapy, although this conclusion will require verification in extended clinical trials.     

Laparoscopic placement of peritoneal dialysis catheters: 7 years experience

Background: Since 1994 we have placed all peritoneal dialysis (Tenckhoff) catheters at our hospital laparoscopically using a technique that incorporates suture fixation into the pelvis. The purpose of this study was to determine the long‐term outcome of this approach. Method: Perioperative and follow‐up data for all patients undergoing placement of a peritoneal dialysis catheter at the Royal Adelaide Hospital were collected prospectively and managed on unit specific and hospital wide computerized databases. A total of 148 procedures were carried out in 123 patients from March 1994 to November 2001. Follow‐up ranged from 3 to 68 months (median, 42 months). All procedures were undertaken or supervised by one surgeon, and catheters were routinely sutured into the pelvis at laparoscopy. Results: There was no perioperative mortality in this series, and only one catheter could not be placed laparoscopically. This was in a patient with extensive intra‐abdominal adhesions. Mean operative time was 27 min (range, 10?100 min), and mean postoperative stay was 2.8 days (range, 1?12 days). Seven (5%) patients experienced peri/postoperative haemorrhage, and four of these underwent surgical re‐exploration. Twenty‐five (17%) catheters are still used for dialysis. Thirty‐four (23%) catheters were removed when the recipient received a subsequent renal transplant, and 42 (28%) patients died during follow‐up. Forty‐six (31%) patients required catheter revision or removal because of technical problems; 26 (18%) recurrent peritonitis or exit site infection; and 20 (14%) catheter blockage. Twenty‐eight reinsertion procedures were carried out in 25 patients. Ten (7%) patients developed port site hernias at late follow‐up, and required hernioplasty. Catheter migration leading to malfunction (poor drainage) occurred in eight (5%) patients only. Conclusions: Laparoscopic placement of peritoneal dialysis catheters is a safe and effective procedure. The majority of patients will dialyse successfully using this technique. Suturing the catheter tip into the pelvis is associated with a low rate of catheter migration.     

Peritoneal dialysis catheters: a comparison between percutaneous and conventional surgical placement techniques

Percutaneous peritoneal dialysis catheter (PDC) placement isa well-tolerated, rapidly performed side-room procedure thatallows the rapid initiation of dialysis without the delay imposedin co-ordinating a surgeon, theatre time, and theatre staff.We retrospectively reviewed the clinical outcome of 230 PDCinserted over a 30-month period. Fifty were placed percutan-eously(group P) and 180 were placed using conventional surgical techniques,107 in patients commencing CAPD (group A) and 73 in patientspreviously established on CAPD (group B). Total experience accumulatedwas 2563 patient months: 270 patient months group P, 1381 patientmonths group A, 912 patient months group B. Percutaneous PDCinsertion was non-elective, and reserved for patients unfitfor general anaesthesia or haemodialysis. Group P patients wereolder (P<0.001) and had increased early mortality (P<0.005)due to underlying pathology. Death and early mechanical failurecontributed to a shorter mean duration of catheter use in groupP (9.0 ± 2.3 months compared to 15.3 ± 9.6 monthsgroup A and 17.3 ±9.7 group B) (P<0.05). The peritonitisrate was similar in group P (1 per 6.75 patient months) andgroup B (1 per 7.4 patient months) but significantly lower ingroup A (1 per 15.7 patient months) (P<0.01). We concludethat percutaneous PDC placement provides a safe, reliable accessfor peritoneal dialysis and is especially suitable for ill patientswho would not tolerate general anaesthesia.     

Growth,development and nutritional status in Japanese children under 2 years on continuous ambulatory peritoneal dialysis

We examined the growth, development and nutritional status over a period of 10 years of 15 young children (<2 years old) on continuous ambulatory peritoneal dialysis (CAPD). There were 6 males and 9 females with a mean age of 12.5 months, mean weight of 6.3 kg, mean height of 66.2 cm at the start of CAPD and a mean duration of therapy of 2.6 years. Height, weight, head circumference, development quotient (DQ), blood chemistry and dietary intake were assessed over a period of 10 years. The patients' mean height standard deviation score (SDS) did not change significantly (from –2.51 to –2.74) during CAPD therapy. The mean growth velocity index (GVI) during CAPD was 76.5% and correlated positively with energy intake but not with protein intake. The mean DQ was low (67.0%) at the start of CAPD and 69.3% at the end of CAPD. DQ did not correlate with energy intake, GVI, head circumference SDS or with the weight/height ratio; however, 2 patients with low DO (<60%) had a low energy intakes. Although most patients had a low DQ, the IQ at 5–6 years of age was normal in all patients except 1 without cerebral disease. Our study showed minimal growth (SDS) and mental developmental (IQ) delays during CAPD therapy, but an adequate nutritional intake must be assured to obtain the above results.     

Peritoneal dialysis fluid-induced changes of the peritoneal membrane are reversible after peritoneal rest in rats.

BACKGROUND: Peritoneal dialysis (PD) is associated with functional and structural alterations of the peritoneal membrane. However, the (ir)reversibility of these pathological changes of the peritoneum is not understood fully. METHODS: In an experimental PD model, rats (n = 15) received daily 10 ml conventional glucose containing PD fluid, via peritoneal catheters connected to implanted subcutaneous mini vascular access ports. After 5 weeks of treatment, the first group of animals (PDF; n = 10) was sacrificed, while peritoneal catheters of the remaining group of rats (PD-rest; n = 5) were removed 1 week later. The latter group (PD-rest) was sacrificed 12 weeks after removing catheters. At both time points, untreated rats were included as controls. Cellular and morphological parameters were analysed by light and electron microscopy. RESULTS: Rats exposed to PD fluid for 5 weeks showed a severe angiogenesis in various peritoneal tissues. Peritoneal rest resulted in a significant reduction in blood vessel density in visceral (mesentery, P<0.05), but not in parietal peritoneum. Five weeks' exposure to PD fluid resulted in a profound fibrosis in the parietal peritoneum, whereas the degree of fibrosis was significantly reduced in the PD-rest group (P<0.02). Daily exposure to PD fluid induced a higher number of mast cells in the omentum compared with untreated rats, whereas peritoneal rest normalized the increased mast cell density completely (P<0.03). Likewise, continued PD fluid instillation evoked a strong omental milky spot response, which was returned to the control level after peritoneal rest (P<0.009). Furthermore, the number of mesothelial cells on the liver was significantly increased in rats treated with PD fluid, whereas animals from the PD-rest group had a lower number of mesothelial cells, although this was not statistically significant (P = 0.08). Finally, as evidenced by electron microscopy, daily exposure to PD fluid resulted in severe damage to the mesothelial cell layer covering the peritoneum, whereas this cell layer was completely recovered after peritoneal rest. CONCLUSIONS: We show that PD fluid-induced cellular and morphological alterations of the peritoneal membrane are generally reversible.