Annabelle N. Chua

Fluid Overload and Mortality in Children Receiving Continuous Renal Replacement Therapy: The Prospective Pediatric Continuous Renal Replacement Therapy Registry

BACKGROUND Critically ill children with hemodynamic instability and acute kidney injury often develop fluid overload. Continuous renal replacement therapy (CRRT) has emerged as a favored modality in the management of such children. This study investigated the association between fluid overload and mortality in children receiving CRRT. STUDY DESIGN Prospective observational study. SETTING & PARTICIPANTS 297 children from 13 centers across the United States participating in the Prospective Pediatric CRRT Registry. PREDICTOR Fluid overload from intensive care unit (ICU) admission to CRRT initiation, defined as a percentage equal to (fluid in [L] - fluid out [L])/(ICU admit weight [kg]) x 100%. OUTCOME & MEASUREMENTS The primary outcome was survival to pediatric ICU discharge. Data were collected regarding demographics, CRRT parameters, underlying disease process, and severity of illness. RESULTS 153 patients (51.5%) developed < 10% fluid overload, 51 patients (17.2%) developed 10%-20% fluid overload, and 93 patients (31.3%) developed > or = 20% fluid overload. Patients who developed > or = 20% fluid overload at CRRT initiation had significantly higher mortality (61/93; 65.6%) than those who had 10%-20% fluid overload (22/51; 43.1%) and those with < 10% fluid overload (45/153; 29.4%). The association between degree of fluid overload and mortality remained after adjusting for intergroup differences and severity of illness. The adjusted mortality OR was 1.03 (95% CI, 1.01-1.05), suggesting a 3% increase in mortality for each 1% increase in severity of fluid overload. When fluid overload was dichotomized to > or = 20% and < 20%, patients with > or = 20% fluid overload had an adjusted mortality OR of 8.5 (95% CI, 2.8-25.7). LIMITATIONS This was an observational study; interventions were not standardized. The relationship between fluid overload and mortality remains an association without definitive evidence of causality. CONCLUSIONS Critically ill children who develop greater fluid overload before initiation of CRRT experience higher mortality than those with less fluid overload. Further goal-directed research is required to accurately define optimal fluid overload thresholds for initiation of CRRT.

Demographic Characteristics of Pediatric Continuous Renal Replacement Therapy: A Report of the Prospective Pediatric Continuous Renal Replacement Therapy Registry

BACKGROUND This article reports demographic characteristics and intensive care unit survival for 344 patients from the Prospective Pediatric Continuous Renal Replacement Therapy (ppCRRT) Registry, a voluntary multicenter observational network. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS Ages were newborn to 25 yr, 58% were male, and weights were 1.3 to 160 kg. Patients spent a median of 2 d in the intensive care unit before CRRT (range 0 to 135). At CRRT initiation, 48% received diuretics and 66% received vasoactive drugs. Mean blood flow was 97.9 ml/min (range 10 to 350 ml/min; median 100 ml/min); mean blood flow per body weight was 5 ml/min per kg (range 0.6 to 53.6 ml/min per kg; median 4.1 ml/min per kg). Days on CRRT were <1 to 83 (mean 9.1; median 6). A total of 56% of circuits had citrate anticoagulation, 37% had heparin, and 7% had no anticoagulation. RESULTS Overall survival was 58%; survival differed across participating centers. Survival was lowest (51%) when CRRT was started for combined fluid overload and electrolyte imbalance. There was better survival in patients with principal diagnoses of drug intoxication (100%), renal disease (84%), tumor lysis syndrome (83%), and inborn errors of metabolism (73%); survival was lowest in liver disease/transplant (31%), pulmonary disease/transplant (45%), and bone marrow transplant (45%). Overall survival was better for children who weighed >10 kg (63 versus 43%; P = 0.001) and for those who were older than 1 yr (62 versus 44%; P = 0.007). CONCLUSIONS CRRT can be used successfully for a wide range of critically ill children. Survival is best for those who have acute, specific abnormalities and lack multiple organ involvement; sicker patients with selected diagnoses may have lower survival. Center differences might suggest opportunities to define best practices with future study.

The effect of vascular access location and size on circuit survival in pediatric continuous renal replacement therapy: a report from the PPCRRT registry.

Purpose Well-functioning vascular access is essential for the provision of adequate CRRT However, few data exist to describe the effect of catheter size or location on CRRT performance in the pediatric population. Methods Data for vascular access site, size, and location, as well as type of anticoagulant used and patient demographic data were gathered from the ppCRRT registry. Kaplan-Meier curves were generated and then analyzed by log-rank test or Cox Proportional Hazards model. Results Access diameter was found to significantly affect circuit survival. None of the 5 French catheters lasted longer than 20 hours. Seven and 9 French, but not 8 French, catheters fared worse than larger diameter catheters (p=0.002). Circuits associated with internal jugular access survived longer than subclavian or femoral access associated circuits (p<0.05). Circuit survival was also found to be favorably associated with the CVVHD modality (p<0.001). Conclusions Functional CRRT circuit survival in children is favored by larger catheter diameter, internal jugular vein insertion site and CVVHD. For patients requiring catheter diameters less than 10 French, CRRT circuit survival might be optimized if internal jugular vein insertion is feasible. Conversely, when a vascular access site other than the internal jugular vein is most prudent, consideration should be given to using the largest diameter catheter appropriate for the size of the child. The CVVHD modality was associated with longer circuit survival, but the mechanism by which this occurs is unclear.

Protein and calorie prescription for children and young adults receiving continuous renal replacement therapy : A report from the Prospective Pediatric Continuous Renal Replacement Therapy Registry Group

Objective:Few published reports describe nutrition provision for critically ill children and young adults with acute kidney injury receiving continuous renal replacement therapy. The goals of this study were to describe feeding practices in pediatric continuous renal replacement therapy and to evaluate factors associated with over- and under-prescription of protein and calories. Design:Retrospective database study. Setting:Multicenter study in pediatric critical care units. Patients:Patients with acute kidney injury (estimated glomerular filtration rate <75 mL/min/1.73 m2 at continuous renal replacement therapy initiation) enrolled in the Prospective Pediatric Continuous Renal Replacement Therapy Registry. Interventions:None. Measurements:Nutrition variables: initial and maximal protein (g/kg/day) and caloric (kcal/kg/day) prescription and predicted resting energy expenditure (kcal/kg/day). We determined factors predicting initial and maximal protein and caloric prescription by multivariate analysis. Results:One hundred ninety-five patients (median [interquartile range] age = 8.1 [12.8] yrs, 56.9% men) were studied. Mean protein and caloric prescriptions at continuous renal replacement therapy initiation were 1.3 ± 1.5 g/kg/day (median, 1.0; range, 0–10) and 37 ± 27 kcal/kg/day (median, 32; range, 0–107). Mean maximal protein and caloric prescriptions during continuous renal replacement therapy were 2.0 ± 1.5 g/kg/day (median, 1.7; range, 0–12) and 48 ± 32 kcal/kg/day (median, 43; range, 0–117). Thirty-four percent of patients were initially prescribed <1 g/kg/day protein; 23% never attained >1 g/kg/day protein prescription. By continuous renal replacement therapy day 5, median protein prescribed was >2 g/kg/day. Protein prescription practices differed substantially between medical centers with 5 of 10 centers achieving maximal protein prescription of >2 g/kg/day in ≥40% of patients. Caloric prescription exceeded predicted resting energy expenditure by 30%–100%. Factors independently associated with maximal protein and caloric prescription while on continuous renal replacement therapy were younger age, initial protein and caloric prescription and number of continuous renal replacement therapy treatment days (p < 0.05). Conclusions:Protein prescription in pediatric continuous renal replacement therapy may be inadequate. Inter-center variation exists with respect to nutrition prescription. Feeding practice standardization and research in pediatric acute kidney injury nutrition are essential to begin providing evidence-based feeding recommendations.

Topical Mupirocin/Sodium Hypochlorite Reduces Peritonitis and Exit-Site Infection Rates in Children

BACKGROUND AND OBJECTIVES Peritoneal dialysis (PD) is a common maintenance renal replacement modality for children with ESRD frequently compromised by infectious peritonitis and catheter exit site and tunnel infections (ESI/TI). The effect of topical mupirocin (Mup) and sodium hypochlorite (NaOCl) solution was evaluated as part of routine daily exit site care on peritonitis and ESI/TI rates, causative microorganisms, and catheter survival rates. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Retrospective chart review of children on home continuous cycling PD between April 1, 2001 and June 30, 2007 was performed. Infection rates were examined based on exit site protocol used in two different periods: Mup alone, April 1, 2001 to November 17, 2004; and Mup and NaOCl (Mup+NaOCl), November 18, 2004 to June 30, 2007. RESULTS Eighty-three patients (mean PD initiation age: 12.1 +/- 5.8 yr) received home PD over 2009 patient months. Annualized rates (ARs) for peritonitis decreased from 1.2 in the Mup period to 0.26 in the Mup+NaOCl period (P < 0.0001). ARs for ESI/TI decreased from 1.36 in the Mup period to 0.33 in the Mup+NaOCl period (P < 0.0001). No infections with Mup-resistant organisms were observed when either Mup or Mup+NaOCl was used for prophylaxis. Gram-negative-organism associated peritonitis decreased from an AR of 0.31 in the Mup period to 0.07 in the Mup+NaOCl period (P < 0.001). Infection-related catheter removal rates decreased from 1 in 38.9 catheter-months in the Mup period to 1 in 94.2 in the Mup+NaOCl period (P = 0.01). Catheter survival rates were longer in the Mup+NaOCl period (Kaplan-Meier, P < 0.009). CONCLUSIONS The combination Mup+NaOCl in daily exit site care was very effective to reduce PD catheter-associated infections and prolong catheter survival in pediatric patients.

Nonrenal indications for continuous renal replacement therapy: A report from the Prospective Pediatric Continuous Renal Replacement Therapy Registry Group.

Objective: Continuous renal replacement therapy is the most often implemented dialysis modality in the pediatric intensive care unit setting for patients with acute kidney injury. However, it also has a role in the management of patients with nonrenal indications such as clearance of drugs and intermediates of disordered cellular metabolism. Measurements and Methods: Using data from the multicenter Prospective Pediatric Continuous Renal Replacement Therapy Registry, we report a cohort of pediatric patients receiving continuous renal replacement therapy for nonrenal indications. Nonrenal indications were obtained from the combination of “other” category for continuous renal replacement therapy initiation and patient diagnosis (both primary and secondary). This cohort was further divided into three subgroups: inborn errors of metabolism, drug toxicity, and tumor lysis syndrome. Results: From 2000 to 2005, a total of 50 continuous renal replacement therapy events with nonrenal indications for therapy were included in the Prospective Pediatric Continuous Renal Replacement Therapy Registry. Indication-specific survival of the subgroups was 62% (inborn errors of metabolism), 82% (tumor lysis syndrome), and 95% (drug toxicity). The median small solute dose delivered among the subgroups ranged from 2125 to 8213 mL/1.73 m2/hr, with 54%–59% receiving solely diffusion-based clearance as continuous venovenous hemodialysis. No association was established between survival and dose delivered, modality of continuous renal replacement therapy, or use of intermittent hemodialysis prior to continuous renal replacement therapy. Conclusions: Pediatric patients requiring continuous renal replacement therapy for nonrenal indications are a distinct cohort within the population receiving renal replacement therapy with little published experience of outcomes for this group. Survival within this cohort varies by indication for continuous renal replacement therapy and is not associated with continuous renal replacement therapy modality. Additionally, survival is not associated with small solute doses delivered within a cohort receiving >2000 mL/1.73 m2/hr. Our data suggest metabolic control is established rapidly in pediatric patients and that acute detoxification may be provided with continuous renal replacement therapy for both the initial and maintenance phases of treatment using either convection or diffusion at appropriate doses.

Stenosing ureteritis in a 7-year-old boy with Henoch–Schönlein purpura nephritis: A case report and review of the literature

INTRODUCTION Urinary tract obstruction resulting from Henoch-Schönlein purpura (HSP) is an extremely rare urologic entity. If the genitourinary system is involved, it is primarily in the form of a focal proliferative glomerulonephritis. Stenosing disease has received little attention in the literature and treatment options are limited. Despite early intervention renal loss may be inevitable. CASE REPORT A 7-year-old African American male presented with renal failure secondary to bilateral sclerosing ureteritis 1 month after initial presentation with HSP. There was significant disease progression and he required multiple procedures, ultimately bilateral ureterocalycostomies and a left nephrectomy. DISCUSSION HSP is an immune-mediated necrotizing vasculitis. It can affect any organ system; however, in the genitourinary system, focal proliferative glomerulonephritis is a common manifestation, occurring in 20-90% of cases [8]. Extrarenal manifestations are rare. CONCLUSION Ureteritis and obstruction may be late occurrences, but should be considered in all patients presenting with a history of HSP and new-onset flank pain, acute renal failure, or anuria. Families and patients should be counseled that renal impairment may be a consequence of stenosing ureteritis. Management of these patients can be complicated but surgical correction must be considered in the treatment algorithm once the disease has stabilized.

Care of the Pediatric Patient on Chronic Dialysis

Optimal care of the pediatric end-stage renal disease (ESRD) patient on chronic dialysis is complex and requires multidisciplinary care as well as patient/caregiver involvement. The dialysis team, along with the family and patient, should all play a role in choosing the dialysis modality which best meets the patients needs, taking into account special considerations and management issues that may be particularly pertinent to children who receive peritoneal dialysis or hemodialysis. Meticulous attention to dialysis adequacy in terms of solute and fluid removal, as well as to a variety of clinical manifestations of ESRD, including anemia, growth and nutrition, chronic kidney disease-mineral bone disorder, cardiovascular health, and neurocognitive development, is essential. This review highlights current recommendations and advances in the care of children on dialysis with a particular focus on preventive measures to minimize ESRD-associated morbidity and mortality. Advances in dialysis care and prevention of complications related to ESRD and dialysis have led to better survival for pediatric patients on dialysis.