NKF KDOQI GUIDELINES

Clinical Practice Guidelines and Clinical Practice Recommendations
2006 Updates
Hemodialysis Adequacy
Peritoneal Dialysis Adequacy
Vascular Access


I.  CLINICAL PRACTICE GUIDELINES FOR PERITONEAL DIALYSIS ADEQUACY

GUIDELINE 6. PEDIATRIC PERITONEAL DIALYSIS

INTRODUCTION

The provision of evidence-based pediatric PD adequacy guidelines is hampered by a number of epidemiological issues. CKD stage 5 remains a relatively uncommon disease in children, while kidney transplantation is still the predominant mode of KRT. In addition, HD is a viable modality option for many pediatric patients, especially adolescents. Finally, children with CKD stage 5 show significantly better survival rates compared with adult patients. As a result of these factors, no long-term pediatric outcome study similar to the ADEMEX Study is adequately powered to detect an effect of the delivered PD dose on pediatric patient outcome.38 Nevertheless, pediatric data exist, for example, to describe the most accurate methods for assessing peritoneal membrane transport capacity and quantifying urea removal.146-148 These data and others can serve as a basis for CPGs in children receiving PD. For areas in which no pediatric-specific data exist, the CPGs and CPRs for adult patients should serve as a minimum standard for pediatric patients, but the overall clinical “wellness” of the individual pediatric patient should be the primary factor that influences the quantity and quality of the care provided.

6.1 Recommended laboratory measurements for peritoneal membrane function:

6.2 Maintenance of euvolemia and normotension:

6.3 Quality improvement programs:

RATIONALE

Recommended Laboratory Measurements for Peritoneal Membrane Function
The PET is the most common technique used clinically in children to assess peritoneal membrane transport capacity and guide the prescription process, although other means of membrane assessment have been reported.146,147,149 Addition of a volume marker during the PET also can provide valuable information regarding fluid handling. Institution of a standardized PET procedure for children has resulted from recognition of the age-independent relationship between BSA and peritoneal membrane surface area and the resultant recommendation for use of a test exchange volume scaled to BSA when one conducts studies of peritoneal transport kinetics in children.150-152 Based on 2 large-scale studies and resultant normative data, the PET in children should be performed with an exchange volume of 1,000 to 1,100 mL/m2 BSA.146,147 Provision of a smaller volume characteristically results in more rapid equilibration of solute between blood and dialysate and the artifactual appearance of an inherently increased (more rapid) membrane transport capacity.153 Repeated PET testing is recommended when knowledge of the patient's current membrane transport capacity is necessary for determination of the patient's PD prescription (eg, in the setting of suboptimal clearance), especially when clinical events have occurred (eg, repeated peritonitis) that may have altered membrane transport characteristics.154,155 Kinetic modeling programs have been developed that use peritoneal membrane transport test data from the standard PET and PD capacity (PDC) tests to help in prescription management. These have been validated for clinical use in pediatrics.151,156

Maintenance of Euvolemia and Normotension
Hypertension is a common complication of children receiving dialysis. As delineated in the KDOQI CVD Guidelines, determination and management of blood pressure in children should follow recommendations by the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents.157,158 In that report, it is recommended that the optimal (normal) SBP and DBP should be less than the 90th percentile for age, sex, and height.

A recent analysis of data from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) found that 56.9% of nearly 4,000 dialysis patients had uncontrolled hypertension (blood pressure > than the age-, sex-, and height-specific 95th percentile) and an additional 19.7% of patients had controlled hypertension (blood pressure < the 95th percentile with antihypertensive medication).159 In addition, marked echocardiographic changes have been documented in pediatric patients at both the initiation of dialysis therapy and during maintenance dialysis therapy. A retrospective study of 64 long-term dialysis patients found that 48 children (75%) had LVH, including 26 of 38 children (68%) on PD therapy.160 Similarly, another report showed increased left ventricular mass (LVM) and LVMI in children receiving dialysis compared with a healthy population.161 Whereas the cause of the elevated blood pressure is multifactorial, others found that high blood pressure and cardiac impairment were most frequent in the younger and nephrectomized dialysis patients for whom volume overload appeared to be the most important etiologic factor.162

Proper fluid management requires knowledge and repeated monitoring of the patient's daily residual kidney volume and daily ultrafiltration volume. Efforts to modify the dialysis prescription with the goal of enhancing ultrafiltration with the lowest possible dialysate dextrose concentration are conducted best with knowledge of the patient's peritoneal membrane transport capacity as derived from the PET. If patients are characterized as high/rapid transporters and are unable to achieve the ultrafiltration necessary for blood pressure control with standard dialysis solutions, consideration should be given to the use of an icodextrin-based dialysis solution.163,164 Whereas its use has been associated with enhanced ultrafiltration in pediatric patients, a recent report suggests that icodextrin-associated fluid removal correlated significantly with age and that icodextrin may behave differently in young children in whom ultrafiltration may not be as successful.165 This experience has not been duplicated in other centers and requires confirmation.

Recommendations for antihypertensive therapy in children are provided in the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents, as well as in the KDOQI Clinical Practice Guidelines on Hypertension and Antihypertensive Agents in CKD.157,166

Finally, in some patients who are polyuric, negative net daily ultrafiltration may be desirable because of its potential to replenish decreased intravascular volume and improve RKF. When negative net daily ultrafiltration is not possible, provision of additional fluids is recommended.

Quality Improvement Programs
A CQI program should be instituted in all dialysis facilities that care for children receiving PD, based on evidence that improvements in patient care are best achieved in this manner. In addition to monitoring outcomes related to, for example, complications related to infection, achievement of solute clearance targets, adequacy of nutrition, osteodystrophy, anemia management, and QOL, school attendance/performance and growth are key issues to be monitored in any program caring for children receiving long-term dialysis. Not surprisingly, data collected by the NAPRTCS showed that children receiving PD regularly show better school attendance than those on HD therapy.167 However, differences exist in the PD population when attendance is stratified by race, an issue that requires attention and often intervention. The recommendation for regular growth assessment, as previously delineated in the pediatric component of the KDOQI Nutrition Guidelines, results from the negative impact that CKD can have on height velocity and the association between poor growth and poor outcome in children receiving dialysis.35,168 The use and influence of medical interventions (eg, correction of acid-base abnormalities, control of secondary hyperparathyroidism and renal osteodystrophy, provision of adequate nutrition, and institution and effect of recombinant human growth hormone therapy) also should be monitored.168A-171

Although programs with varying levels of pediatric expertise coordinate the care of children receiving long-term dialysis, ideally, a treatment facility should be able to provide the necessary multidisciplinary services required by children and families through a team of specialists with pediatric experience. All these disciplines should be involved in the CQI process.172

In view of the relatively small number of children who receive PD in any one center, it is imperative that single-center data be compared with results contained in large pediatric databases to determine whether modification of a center's program is deemed necessary. Organizations such as the NAPRTCS and USRDS provide such data.24,173

LIMITATIONS

Although attention to fluid management likely will benefit blood pressure control and help prevent the development of CVD in children receiving PD, no large-scale study of the pediatric CKD stage 5 population has proved this to be true.

Although CQI programs generally are considered to be beneficial, there are no studies of pediatric PD facilities that document the efficacy of such programs in terms of their ability to improve patient outcomes.

While it is intuitively beneficial for the CQI program to be multidisciplinary in nature, quality standards for some disciplines in terms of their application to the pediatric PD population have not yet been established.