Prognosis for children with acute kidney injury in the intensive care unit

Adolescence-onset atypical hemolytic uremic syndrome: is it different from infant-onset?

BACKGROUND

Atypical hemolytic uremic syndrome (aHUS) is a rare, mostly complement-mediated thrombotic microangiopathy. The majority of patients are infants. In contrast to infantile-onset aHUS, the clinical and genetic characteristics of adolescence-onset aHUS have not been sufficiently addressed to date.

METHODS

A total of 28 patients (21 girls, 7 boys) who were diagnosed as aHUS between the ages of ≥10 years and <18 years were included in this study. All available data in the Turkish Pediatric aHUS registry were collected and analyzed.

RESULTS

The mean age at diagnosis was 12.8±2.3 years. Extra-renal involvement was noted in 13 patients (46.4%); neurological involvement was the most common (32%). A total of 21 patients (75%) required kidney replacement therapy. Five patients (17.8%) received only plasma therapy and 23 (82%) of the patients received eculizumab. Hematologic remission and renal remission were achieved in 25 (89.3%) and 17 (60.7%) of the patients, respectively. Compared with the infantile-onset aHUS patients, adolescent patients had a lower complete remission rate during the first episode (p = 0.002). Genetic analyses were performed in all and a genetic variant was detected in 39.3% of the patients. The mean follow-up duration was 4.9±2.6 years. At the last visit, adolescent patients had lower eGFR levels (p = 0.03) and higher rates of chronic kidney disease stage 5 when compared to infantile-onset aHUS patients (p = 0.04).

CONCLUSIONS

Adolescence-onset aHUS is a rare disease but tends to cause more permanent renal dysfunction than infantile-onset aHUS. These results may modify the management approaches in these patients.

Pediatric nephrologist-intensivist interaction in acute kidney injury

INTRODUCTION

Acute Kidney Injury (AKI) in the Intensive Care Unit (ICU) have concepts of diagnosis and management have water balance as their main point of evaluation. In our ICU, from 2004 to 2012, the nephrologist's participation was on demand only; and as of 2013 their participation became continuous in meetings to case discussion. The aim of this study was to establish how an intense nephrologist/intensivist interaction influenced the frequency of dialysis indication, fluid balance and pRIFLE classification during these two observation periods.

METHODS

Retrospective study, longitudinal evaluation of all children with AKI undergoing dialysis (2004 to 2016).

PARAMETERS STUDIED

frequency of indication, duration and volume of infusion in the 24 hours preceding dialysis; diuresis and water balance every 8 hours. Non-parametric statistics, p ≤ 0.05.

RESULTS

53 patients (47 before and 6 after 2013). There were no significant differences in the number of hospitalizations or cardiac surgeries between the periods. After 2013, there was a significant decrease in the number of indications for dialysis/year (5.85 vs. 1.5; p = 0.000); infusion volume (p = 0.02), increase in the duration of dialysis (p = 0.002) and improvement in the discrimination of the pRIFLE diuresis component in the AKI development.

CONCLUSION

Integration between the ICU and pediatric nephrology teams in the routine discussion of cases, critically approaching water balance, was decisive to improve the management of AKI in the ICU.

Clinical characteristics and outcomes of continuous renal replacement therapy performed on younger children weighing up to 10 kg

BACKGROUND

This study aimed to investigate the clinical features, modality, complications, and effecting factors on the survival of children weighing up to 10 kg who received continuous renal replacement therapy (CRRT).

METHODS

This study was a retrospective observational study conducted in five pediatric intensive care units in tertiary hospitals in Turkey between January 2015 and December 2019.

RESULTS

One hundred and forty-one children who underwent CRRT were enrolled in the study. The median age was 6 (range, 2-12)months, and 74 (52.5%) were male. The median weight of the patients was 6 (range, 4-8.35) kg and 52 (36.9%) weighed less than 5 kg. The most common indication for CRRT was fluid overload in 75 (53.2%) patients, and sepsis together with multiorgan failure in 62 (44%). The overall mortality was 48.2%.

DISCUSSION

Despite its complexity, CRRT in children weighing less than 10 kg is a beneficial, lifesaving extracorporeal treatment modality.

A Validation Study of Administrative Health Care Data to Detect Acute Kidney Injury in the Pediatric Intensive Care Unit

Background

Large studies evaluating pediatric acute kidney injury (AKI) epidemiology and outcomes are lacking, partially due to underuse of large administrative health care data.

Objective

To assess the diagnostic accuracy of administrative health care data-defined AKI in children admitted to the pediatric intensive care unit (PICU).

Design

Retrospective cohort study utilizing chart and administrative data.

Setting

Children admitted to the PICU at 2 centers in Montreal, QC.

Patients

Patients between 0 and 18 years old with a provincial health insurance number, without end-stage renal disease and admitted to the PICU between January 1, 2003, and March 31, 2005, were included.

Measurements

The AKI was defined from chart data using the Kidney Disease: Improving Global Outcomes (KDIGO) definition (Chart-AKI). The AKI defined using administrative health data (Admin-AKI) was based on International Classification of Disease, Ninth Revision (ICD-9) AKI codes.

Methods

Data available from retrospective chart review, including baseline and PICU patient characteristics, and serum creatinine (SCr) and urine output (UO) values during PICU admission, were merged with provincial administrative health care data containing diagnostic and procedure codes used for ascertaining Admin-AKI. Sensitivity, specificity, positive, and negative predictive value of Admin-AKI compared with Chart-AKI (reference standard) were calculated. Univariable associations between Admin-AKI and hospital mortality were evaluated.

Results

A total of 2051 patients (55% male, mean age at admission 6.1 ± 5.8 years, 355 cardiac surgery, 1696 noncardiac surgery) were included. The AKI defined by SCr or UO criteria occurred in 52% of cardiac surgery patients and 24% of noncardiac surgery patients. Overall, Admin-AKI detected Chart-AKI with low sensitivity, but high specificity in cardiac and noncardiac surgery patients. Sensitivity increased by 1.5 to 2 fold with each increase in AKI severity stage. Admin-AKI was associated with hospital mortality (13% in Admin-AKI vs 2% in non-AKI, P < .001).

Limitations

These data were generated in a PICU population; future research should study non-PICU populations.

Conclusions

Use of administrative health care data to define AKI in children leads to AKI incidence underestimation. However, for detecting more severe AKI, sensitivity is higher, while maintaining high specificity.

Acute Kidney Injury Epidemiology in pediatrics

We performed a search in the MEDLINE database using the MeSH term: "Acute Kidney Injury", selecting the subtopic "Epidemiology", and applying age and year of publication filters. We also searched for the terms: "acute renal failure" and "epidemiology" "acute tubular necrosis" and "epidemiology" in the title and summary fields with the same filters. In a second search, we searched in the LILACS database, with the terms: "acute renal injury", or "acute renal failure" or "acute kidney injury" and the age filter. All abstracts were evaluated by the authors and the articles considered most relevant, were examined in their entirety. Acute Kidney Injury (AKI) -related mortality ranged from 3-63% in the studies included in this review. AKI etiology has marked regional differences, with sepsis being the main cause in developed countries. In developing countries, primary renal diseases and hypovolemia are still a common cause of AKI.

Community-acquired Acute Kidney Injury Among Children Seen in the Pediatric Emergency Department

OBJECTIVES

Acute kidney injury (AKI) is a significant risk factor for morbidity and mortality in children. Little is known about community-acquired AKI (CA-AKI) in the pediatric emergency department (PED). Early recognition of AKI allows for nephroprotective measures. The goal of this investigation was to determine the incidence of CA-AKI and the frequency of clinician identified CA-AKI to better inform future nephroprotective interventions.

METHODS

This was a retrospective cross-sectional study in the PED of a children's hospital. Children 1 month to 18 years of age seen in the PED from January 1 to December 31, 2015, and in whom at least one creatinine level was obtained were included. Patients with chronic kidney disease or end-stage renal disease or who died in the PED were excluded. Patients had CA-AKI based on modified Kidney Disease-Improving Global Outcomes criteria using the creatinine obtained in the PED compared to age-specific norms. Patients were considered identified if the PED clinician diagnosed AKI. The primary outcome was the incidence of CA-AKI. Secondary outcomes included frequency of AKI identification, nephrotoxic medication use, hospital length of stay, renal replacement therapy, and death. Fisher exact test or Pearson's chi-square test was used to calculate odds ratio (OR) with 95% confidence intervals (CIs); multivariable analyses were performed using logistic regression.

RESULTS

In 2015 there were 119,151 PED visits; 15,486 met inclusion criteria. CA-AKI was present in 239 of 15,486 (1.5%) encounters. AKI was identified by PED clinicians in 46 of 239 (19%) of encounters and by the inpatient team in 123 of 199 (62%) of the encounters admitted. AKI was never recognized by a PED or inpatient clinician in 74 of 199 (37%) encounters. Encounters with AKI correctly diagnosed were older (13 years old vs. 10 years old, p = 0.0114), had more severe (stage 2 or 3) AKI (OR = 5.5, 95% CI = 2.6-11.8), and were more likely to be admitted (OR = 10.3, 95% CI = 1.38-77.4) than encounters with missed AKI.

CONCLUSIONS

CA-AKI remains an underrecognized entity in the PED. Better tools for early recognition of AKI in the busy PED environment are needed.

Factors Associated With Mortality in Continuous Renal Replacement Therapy for Pediatric Patients With Acute Kidney Injury

OBJECTIVES

To analyze the epidemiology of pediatric acute kidney injury requiring continuous renal replacement therapy and identify prognostic factors affecting mortality rates.

DESIGN

Retrospective analysis.

SETTING

PICU of a tertiary medical center.

PATIENTS

One hundred-twenty three children diagnosed with acute kidney injury requiring continuous renal replacement therapy.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Vasoactive-Inotropic Score, arterial blood gas analysis, blood chemistry at continuous renal replacement therapy initiation, the extent of fluid overload 24 hours prior to continuous renal replacement therapy initiation, Pediatric Risk of Mortality III score at admission, and need for mechanical ventilation during continuous renal replacement therapy were compared in survivors and nonsurvivors. Out of 1,832 patient admissions, 185 patients (10.1%) developed acute kidney injury during the study period. Of these, 158 patients were treated with continuous renal replacement therapy, and finally, 123 patients were enrolled. Of the enrolled patients, 50 patients died, corresponding to a mortality rate of 40.6%. The survivor group and the nonsurvivor group were compared, and the following factors were associated with an increased risk of mortality: higher Pediatric Risk of Mortality III score at admission and Vasoactive-Inotropic Score when initiating continuous renal replacement therapy, increased fluid overload 24 hours before continuous renal replacement therapy initiation, and need for mechanical ventilation during continuous renal replacement therapy. The percentage of fluid overload difference between the survivors and the nonsurvivors was 1.2% ± 2.2% versus 4.1% ± 4.6%, respectively. Acidosis, elevated lactic acid and blood urea nitrogen, and lower serum creatinine level were laboratory parameters associated with increased mortality. On multivariate analysis, Vasoactive-Inotropic Score, need for mechanical ventilation, blood urea nitrogen, and creatinine level were statistically significant. (Odds ratio: 1.040, 6.096, 1.032, and 0.643, respectively.) CONCLUSIONS:: A higher Vasoactive-Inotropic Score, need for mechanical ventilation, elevated blood urea nitrogen, and lower creatinine level were associated with increased mortality in pediatric acute kidney injury patients who underwent continuous renal replacement therapy. Lower creatinine levels may be associated with increased mortality in the context of fluid overload, which is correlated with a reduced chance of survival.

Predictive factors of mortality in pediatric patients with acute renal injury associated with sepsis

OBJECTIVE

To evaluate the prognosis factors of children with sepsis and acute kidney injury.

METHODS

This was a retrospective study of children with sepsis and acute kidney injury that were admitted to the pediatric intensive care unit (PICU) of a tertiary hospital. A multivariate analysis was performed to compare risk factors for mortality.

RESULTS

Seventy-seven children (47 males) were retrospectively studied, median age of 4 months. Mean length of hospital stay was 7.33±0.16 days, 68.9% of patients received mechanical ventilation, 25.9% had oligo-anuria, and peritoneal dialysis was performed in 42.8%. The pRIFLE criteria were: injury (5.2%) and failure (94.8%), and the staging system criteria were: stage 1 (14.3%), stage 2 (29.9%), and stage 3 (55.8%). The mortality rate was 33.7%. In the multivariate analysis, the risk factors for mortality were PICU length of stay (OR=0.615, SE=0.1377, 95% CI=0.469-0.805, p=0.0004); invasive mechanical ventilation (OR=14.599, SE=1.1178, 95% CI=1.673-133.7564, p=0.0155); need for dialysis (OR=9.714, SE=0.8088, 95% CI=1.990-47.410, p=0.0049), and hypoalbuminemia (OR=10.484, SE=1.1147, 95% CI=1.179-93.200, p=0.035).

CONCLUSIONS

The risk factors for mortality in children with acute kidney injury were associated with sepsis severity.

Etiology, clinical profile and short-term outcome of acute kidney injury in children at a tertiary care pediatric nephrology center in Pakistan

Background: The reported prevalence rates and etiologies of acute kidney injury (AKI) are quite variable in different regions of the world. The current study was planned to determine the etiology, clinical profile, and short-term outcome of pediatric AKI at our hospital.

Methods: A prospective, observational study was carried out from April 2014 to March 2015. All pediatric patients (1 month to ≤15 years) diagnosed as AKI using modified pRIFLE criteria were studied and followed for 3 months to document short-term outcome.

Results: AKI was diagnosed in 116 children. The mean age was 7.5 ± 4.4 years and males were predominant (60.3%). At presentation, 83.6% had oliguria/anuria, 37.1% hypertension and 17.2% severe anemia. Etiology included primary renal (74/116; 63.8%), postrenal (28/116; 24.1%) and prerenal (11/116; 9.5%) causes. Postinfectious glomerulonephritis (PIGN) and crescentic glomerulonephritis in primary renal, obstructive urolithiasis in postrenal and sepsis in prerenal, were the most common etiologies. At presentation, 89/116 (76.7%) patients were in pRIFLE Failure category. Regarding outcome, 68 (58.6%) patients recovered, six (5.2%) died, 18 (15.5%) developed chronic kidney disease (CKD) and 22 (19%) end-stage renal disease (ESRD). Comparison of recovered and unrecovered AKI showed that characteristics such as hypertension, severe anemia, edema, volume overload, requirement of mechanical ventilation, initiation of dialysis and need of >5 sessions of dialysis had statistically significant (p <0.05) association with nonrecovery.

Conclusion: Glomerulonephritides (PIGN and crescentic) and obstructive urolithiasis are major causes of pediatric AKI at our center. A fairly high percentage of cases recovered and these mainly comprised of PIGN and obstructive urolithiasis.

Risk Factors of Acute Kidney Injury in Critically Ill Children

OBJECTIVES

Acute kidney injury may be promoted by critical illness, preexisting medical conditions, and treatments received both before and during ICU admission. We aimed to estimate the frequency of acute kidney injury during ICU treatment and to determine factors, occurring both before and during the ICU stay, associated with the development of acute kidney injury.

DESIGN

Cohort study of critically ill children.

SETTING

University-affiliated PICU.

PATIENTS

Eligible patients were admitted to the ICU between January 2006 and June 2009. We excluded those admitted with known primary renal failure, chronic renal failure or postrenal transplant, conditions with known renal complications, or metabolic conditions treated with dialysis. Patients were also excluded if they had a short ICU stay (< 6 hr) and those who had no creatinine or urine output measurements during their ICU stay.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 3,865 pediatric patients who met the inclusion criteria, 915 (23.7%) developed acute kidney injury, as classified by the Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease criteria, during their ICU stay. Patients at high risk for development of acute kidney injury included those urgently admitted to the ICU (adjusted odds ratio, 1.88), those who developed respiratory dysfunction during their ICU care (adjusted odds ratio, 2.90), and those who treated with extracorporeal membrane oxygenation (adjusted odds ratio, 2.72). The single greatest risk factor for acute kidney injury was the administration of nephrotoxic medications during ICU admission (adjusted odds ratio, 3.37).

CONCLUSIONS

This study, the largest evaluating the incidence of RIFLE-defined acute kidney injury in critically ill children, found that one-quarter of patients admitted to the ICU developed acute kidney injury. We identified a number of potentially modifiable risk factors, the largest of which was the administration of nephrotoxic medication. The results of this study may be used to inform targeted interventions to reduce acute kidney injury and improve the outcomes of critically ill children.

Acute kidney injury and its association with in-hospital mortality among children with acute infections

BACKGROUND

We investigated prevalence of acute kidney injury (AKI) at hospitalization and its association with in-hospital mortality among Ugandan children hospitalized with common acute infections, and predictors of mortality among AKI children.

METHODS

We enrolled 2,055 children hospitalized with primary diagnoses of acute gastroenteritis, malaria, or pneumonia. Serum creatinine, albumin, electrolytes, hemoglobin, and urine protein were obtained on admission. Participants were assessed for AKI based on serum creatinine levels. Demographic and clinical data were obtained using a primary care provider survey and medical chart review. Logistic regression was used to determine predictors of in-hospital mortality.

RESULTS

A total of 278 (13.5%) of children had AKI on admission; for 76.2%, AKI was stage 2 (98/278) or stage 3 (114/278) defined as serum creatinine >2- or 3-fold above normal upper limit for age, respectively. AKI prevalence was particularly high in gastroenteritis (28.6%) and underweight children (20.7%). Twenty-five percent of children with AKI died during hospitalization, compared to 9.9% with no AKI (adjusted odds ratio (aOR) 3.5 (95% CI, 2.2-5.5)). In-hospital mortality risk did not differ by AKI stage. Predictors of in-hospital mortality among AKI children included primary diagnosis of pneumonia, aOR 4.5 (95% CI, 1.8-11.2); proteinuria, aOR = 2.1 (95% CI, 1.0-4.9) and positive human immunodeficiency virus (HIV) status, aOR 5.0 (95% CI, 2.0-12.9).

CONCLUSIONS

Among children hospitalized with gastroenteritis, malaria, or pneumonia, AKI at admission was common and associated with high in-hospital mortality.

Continuous renal replacement therapy in children after cardiac surgery

OBJECTIVE

The objective was to study the clinical course of children requiring continuous renal replacement therapy (CRRT) after cardiac surgery and to analyze the factors associated with mortality.

METHODS

A prospective observational study was performed that included all children requiring CRRT after cardiac surgery, comparing these patients with other critically ill children requiring CRRT. Univariate and multivariate analyses were performed to determine the influence of each factor on mortality.

RESULTS

Eighty-one (4.9%) of 1650 children undergoing cardiac surgery required CRRT; 65 of them (80.2%) presented multiorgan failure. Children starting CRRT after cardiac surgery had lower mean arterial pressure and lower urea and creatinine levels, and were more likely to require mechanical ventilation than other children on CRRT. The incidence of complications was similar. Cardiac surgery increased the probability of requiring CRRT for more than 14 days. Mortality was 43% in children receiving CRRT after cardiac surgery and 29% in other children (P = .05). Factors associated with mortality in the univariate analysis were age less than 12 months, weight less than 10 kg, higher Pediatric Risk of Mortality Score, hypotension, lower urea and creatinine on starting CRRT, and use of hemofiltration. In the multivariate analysis, the only factor associated with mortality was hypotension on starting CRRT (hazard ratio, 4.01; 95% confidence interval, 1.2-13.4; P = .024).

CONCLUSIONS

Although only a small percentage of children undergoing cardiac surgery required CRRT, mortality in these patients was high. Hypotension at the time of starting the technique was the only factor associated with a higher mortality.

Pediatric acute kidney injury assessed by pRIFLE as a prognostic factor in the intensive care unit

BACKGROUND

In this study we applied the pediatric version of the RIFLE criteria (pRIFLE) to an at-risk hospital population, analyzed the incidence and association of acute kidney injury (AKI) with mortality and length of stay in both the intensive care unit (ICU) and the hospital, and evaluated the applicability of pRIFLE as a prognostic tool in the ICU.

METHODS

This study was a prospective single-center cohort study in which 126 patients were enrolled. The affected group included patients who were diagnosed with AKI. Subgroups of the diagnosed patients were established according to their maximum pRIFLE strata, which were defined as the worst pRIFLE score attained during the study period.

RESULTS

Fifty-eight (46 %) of our patients developed AKI. The lengths of stay in the ICU and in the hospital were longer in the affected group than in the unaffected group. The advanced strata of pRIFLEmax were associated with longer stays in the ICU and hospital and higher median Pediatric Index of Mortality II scores. The hospital mortality rate of AKI patients was 12-fold higher than that of the patients without AKI (36 vs. 3 %).

CONCLUSION

The incidence of AKI in this population was both significant and directly associated with hospital mortality and the length of stay in the ICU and hospital. The pRIFLE classification facilitated the definition of AKI, indicating that it a significant prognostic predictor.

Pediatric Acute Kidney Injury: Different From Acute Renal Failure But How And Why

Acute kidney injury [AKI] refers to a clinical syndrome encompassing various etiologies and occurring in a variety of clinical settings, with manifestations ranging from subtle biochemical and structural changes, to minimal elevation in serum creatinine, to anuric renal failure. Understanding the spectrum of AKI and the importance of the early pre-clinical damage stage has resulted in an improved ability to define and stage pediatric AKI, to understand the AKI-to-CKD transition, and harness novel damage biomarkers to predict AKI and its adverse outcomes. These concepts are expanded upon in this review, with an emphasis on publications from the past three years.

Paediatric acute kidney injury in a tertiary hospital in Nigeria: prevalence, causes and mortality rate

Background

The modest decline in child mortality in Africa raises the question whether the pattern of diseases associated with acute kidney injury (AKI) in children in Nigeria has changed.

Methods

A database of children, aged between one month and 16 years, with AKI (using modified pediatric RIFLE criteria) was reviewed. The cause of AKI was defined as the major underlying disease. The clinical and laboratory features of children with AKI who survived were compared to those who died.

Results

Of the 4 015 children admitted into Lagos University Teaching Hospital between July 2010 and July 2012, 70 episodes of AKI were recorded equalling 17.4 cases per 1000 children. The median age of the children with AKI was 4.8 (range 0.1–14.4) years and 68.6% were males. Acute kidney injury was present in 58 (82.9%) children at admission with 70% in ‘failure’ category. Primary kidney disease (38.6%), sepsis (25.7%) and malaria (11.4%) were the commonest causes. The primary kidney diseases were acute glomerulonephritis (11) and nephrotic syndrome (8). Nineteen (28.4%) children with AKI died. Need for dialysis [odds ratio: 10.04 (2.94–34.33)], white cell >15 000/mm³ [odds ratio: 5.72 (1.65–19.89)] and platelet <100 000/mm³ [odds ratio: 9.56 (2.63–34.77)] were associated with death.

Conclusion

Acute kidney injury is common in children admitted to hospitals. The common causes remain primary kidney diseases, sepsis and malaria but the contribution of sepsis is rising while malaria and gastroenteritis are declining. Acute kidney injury-related mortality remains high.

Is serum cystatin C a better marker than serum creatinine for monitoring renal function in pediatric intensive care unit?

In critically ill patients, mild to moderate reductions in glomerular filtration rate are not instantly followed by parallel changes in serum creatinine (SCr). The aim of this study was to identify a value of serum cystatin C (cys-C) level as a marker for monitoring renal function in critically ill pediatric patients. Creatinine clearance was used to estimate glomeruler filtration rate (eGFR). The correlation between the inverse of serum cys-C and eGFR (r = -0.70, p < 0.0001) was better than the correlation between the inverse of SCr and eGFR (r = -0.27, p = 0.008). Serum cys-C was found to be superior to SCr to predict renal impairment (area under the curve for cys-C, 0.932 and for SCr, 0.658). It can be concluded that cys-C is superior to SCr for the detection of renal impairment in critically ill children.

Weight-based determination of fluid overload status and mortality in pediatric intensive care unit patients requiring continuous renal replacement therapy

PURPOSE

In pediatric intensive care unit (PICU) patients, fluid overload (FO) at initiation of continuous renal replacement therapy (CRRT) has been reported to be an independent risk factor for mortality. Previous studies have calculated FO based on daily fluid balance during ICU admission, which is labor intensive and error prone. We hypothesized that a weight-based definition of FO at CRRT initiation would correlate with the fluid balance method and prove predictive of outcome.

METHODS

This is a retrospective single-center review of PICU patients requiring CRRT from July 2006 through February 2010 (n = 113). We compared the degree of FO at CRRT initiation using the standard fluid balance method versus methods based on patient weight changes assessed by both univariate and multivariate analyses.

RESULTS

The degree of fluid overload at CRRT initiation was significantly greater in nonsurvivors, irrespective of which method was used. The univariate odds ratio for PICU mortality per 1% increase in FO was 1.056 [95% confidence interval (CI) 1.025, 1.087] by the fluid balance method, 1.044 (95% CI 1.019, 1.069) by the weight-based method using PICU admission weight, and 1.045 (95% CI 1.022, 1.07) by the weight-based method using hospital admission weight. On multivariate analyses, all three methods approached significance in predicting PICU survival.

CONCLUSIONS

Our findings suggest that weight-based definitions of FO are useful in defining FO at CRRT initiation and are associated with increased mortality in a broad PICU patient population. This study provides evidence for a more practical weight-based definition of FO that can be used at the bedside.

Acute kidney injury: can we improve prognosis?

The incidence of pediatric acute kidney injury (AKI) is increasing. AKI has been found to be independently associated with increased mortality, and current management options are limited in that they are mainly supportive. The use of various definitions of AKI can still be found in the literature, making it difficult to discern the epidemiology behind pediatric AKI. The use of a more uniform definition is a necessary first step to clarify AKI epidemiology and direct our research efforts, and it will ultimately improve prognosis. There is evidence that neonates and infants may be at higher risk for AKI than adults. However, the least amount of research is found for this youngest age group, and more focused efforts on this population are necessary. This paper reviews existing data on and definitions for pediatric AKI, general preventive and treatment strategies, as well as ongoing research efforts on AKI. We are hopeful that the prognosis of AKI will improve with collaboration on a multicenter, multinational scale in the form of prospective, long-term studies on pediatric AKI.

Etiology and outcome of acute kidney injury in children

The aim of this prospective, multicenter study was to define the etiology and clinical features of acute kidney injury (AKI) in a pediatric patient cohort and to determine prognostic factors. Pediatric-modified RIFLE (pRIFLE) criteria were used to classify AKI. The patient cohort comprised 472 pediatric patients (264 males, 208 females), of whom 32.6% were newborns (median age 3 days, range 1-24 days), and 67.4% were children aged >1 month (median 2.99 years, range 1 month-18 years). The most common medical conditions were prematurity (42.2%) and congenital heart disease (CHD, 11.7%) in newborns, and malignancy (12.9%) and CHD (12.3%) in children aged >1 month. Hypoxic/ischemic injury and sepsis were the leading causes of AKI in both age groups. Dialysis was performed in 30.3% of newborns and 33.6% of children aged >1 month. Mortality was higher in the newborns (42.6 vs. 27.9%; p < 0.005). Stepwise multiple regression analysis revealed the major independent risk factors to be mechanical ventilation [relative risk (RR) 17.31, 95% confidence interval (95% CI) 4.88-61.42], hypervolemia (RR 12.90, 95% CI 1.97-84.37), CHD (RR 9.85, 95% CI 2.08-46.60), and metabolic acidosis (RR 7.64, 95% CI 2.90-20.15) in newborns and mechanical ventilation (RR 8.73, 95% CI 3.95-19.29), hypoxia (RR 5.35, 95% CI 2.26-12.67), and intrinsic AKI (RR 4.91, 95% CI 2.04-11.78) in children aged >1 month.

Clinical course and mortality risk factors in critically ill children requiring continuous renal replacement therapy

OBJECTIVE

To study the clinical course in children requiring continuous renal replacement therapy (CRRT) and to analyse factors associated with mortality.

DESIGN

Prospective observational study.

SETTING

Paediatric intensive care department of a tertiary university hospital.

PATIENTS

Critically ill children with CRRT were included in the study.

INTERVENTION

Continuous renal replacement therapy.

MEASUREMENTS AND RESULTS

Univariate and multivariate analyses were performed to analyse the influence of each factor on mortality. The ability of the PRISM, PIM II and PELOD severity of illness scores to predict mortality was tested using receiver-operating characteristic curve statistics. A total of 174 children aged between 1 month and 22 years were treated with CRRT. Mortality was 35.6%, and multiorgan failure and haemodynamic disturbances were the principal causes of death. Mortality was higher in children less than 12 months of age (44.7%; P = 0.037) and in patients with a diagnosis of sepsis (44.1%; P = 0.001). Haemodynamic disturbances at the time of starting CRRT (hypotension or need for adrenaline >0.6 microg/kg/min) and the presence of multiorgan failure were the factors associated with an increased risk of mortality. The PRISM scale was the severity score with the best predictive capacity, although all three scales underestimated the actual mortality.

CONCLUSIONS

Mortality in children who require CRRT is high. Haemodynamic disturbances and the presence of multiorgan failure at the time of starting the technique are the factors associated with a higher mortality. The clinical severity scores underestimate mortality in children requiring CRRT.

Clinical course of children requiring prolonged continuous renal replacement therapy

A prospective observational study was performed to analyze the clinical course of critically ill children who require continuous renal replacement therapy (CRRT). Variables associated with prolonged CRRT were analyzed. Of the 174 children treated with CRRT, 32 (18.3%) required CRRT for >14 days and 20 (11.5%) for >21 days. Prolonged CRRT was more common in patients with heart disease and those requiring mechanical ventilation, hemodiafiltration, and higher doses of heparin. The same factors were found when patients with CRRT for >14 days and 21 days were studied. Overall mortality rate was 35.6%; it was slightly higher in patients on prolonged CRRT (43.7% with CRRT > 14 days and 45% with CRRT >21 days), though the differences were not statistically significant. We conclude that there were no differences in the pre-CRRT clinical characteristics, severity of illness, and renal function in critically ill children requiring prolonged CRRT. Prolonged CRRT was more frequently required by patients with heart disease and those on mechanical ventilation. Patients with prolonged CRRT required more frequent hemodiafiltration and higher doses of heparin. Mortality was slightly higher in children with longer CRRT, though this difference did not reach statistical significance.