Immune urinary biomarkers predict infant cardiac surgery-associated acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) occurs frequently after infant cardiac surgery and is associated with poor outcomes, including mortality and prolonged length of stay. AKI mechanisms are poorly understood, limiting therapeutic targets. Emerging data implicates dysregulated immune activation in post-cardiac surgery AKI development. We sought to identify immune-mediated AKI biomarkers after infant cardiopulmonary bypass (CPB)-assisted cardiac surgery. METHODS: A single-center prospective study of 126 infants less than 1 year old undergoing CPB-assisted surgery enrolled between 10/2017 and 6/2019. Urine samples were collected before CPB and at 6, 24, 48, and 72 h after surgery. Immune-mediated biomarkers were measured using commercial ELISA and Luminex™ multiplex kits. Based on subject age, neonatal KDIGO (< 1 month) or KDIGO criteria defined AKI. The Kruskal-Wallis rank test determined the relationship between urinary biomarker measurements and AKI. RESULTS: A total of 35 infants (27%) developed AKI. AKI subjects were younger, underwent more complex surgery, and had longer CPB time. Subjects with AKI vs. those without AKI had higher median urinary chemokine 10 (C-X-C motif) ligand levels at 24, 48, and 72 h, respectively: 14.3 pg/ml vs. 5.3 pg/ml, 3.4 pg/ml vs. 0.8 pg/ml, and 1.15 pg/ml vs. 0.22 pg/ml (p < 0.05) post-CPB. At 6 h post-CPB, median vascular cell adhesion protein 1 (VCAM) levels (pg/mL) were higher among AKI subjects (491 pg/ml vs. 0 pg/ml, p = 0.04). CONCLUSIONS: Urinary CXCL10 and VCAM are promising pro-inflammatory biomarkers for early AKI detection and may indicate eventual AKI therapeutic targets. A higher resolution version of the Graphical abstract is available as Supplementary information.

Diuretic response after neonatal cardiac surgery: a report from the NEPHRON collaborative.

BACKGROUND: Multicenter early diuretic response (DR) analysis of single furosemide dosing following neonatal cardiac surgery is lacking to inform whether early DR predicts adverse clinical outcomes. METHODS: We performed a retrospective cohort study utilizing data from the NEPHRON registry. Random forest machine learning generated receiver operating characteristic-area under the curve (ROC-AUC) and odds ratios for mechanical ventilation (MV) and respiratory support (RS). Prolonged MV and RS were defined using ≥ 90th percentile of observed/expected ratios. Secondary outcomes were prolonged CICU and hospital length of stay (LOS) and kidney failure (stage III acute kidney injury (AKI), peritoneal dialysis, and/or continuous kidney replacement therapy on postoperative day three) assessed using covariate-adjusted ROC-AUC curves. RESULTS: A total of 782 children were included. Cumulative urine output (UOP) metrics were lower in prolonged MV and RS patients, but DR poorly predicted prolonged MV (highest AUC 0.611, OR 0.98, sensitivity 0.67, specificity 0.53, p = 0.006, 95% OR CI 0.96-0.99 for cumulative 6-h UOP) and RS (highest AUC 0.674, OR 0.94, sensitivity 0.75, specificity 0.54, p < 0.001, 95% CI 0.91-0.97 UOP between 3 and 6 h). Secondary outcome results were similar. DR had fair discrimination for kidney failure (AUC 0.703, OR 0.94, sensitivity 0.63, specificity 0.71, 95% OR CI 0.91-0.98, p < 0.001, cumulative 6-h UOP). CONCLUSIONS: Early DR poorly discriminated patients with prolonged MV, RS, and LOS in this cohort, though it may identify severe postoperative AKI phenotype. Future work is warranted to determine if early DR or late postoperative DR later, in combination with other AKI metrics, may identify a higher-risk phenotype.

Peritoneal catheters in neonates undergoing complex cardiac surgery: a multi-centre descriptive study.

BACKGROUND: The use of peritoneal catheters for prophylactic dialysis or drainage to prevent fluid overload after neonatal cardiac surgery is common in some centres; however, the multi-centre variability and details of peritoneal catheter use are not well described. METHODS: Twenty-two-centre NEonatal and Pediatric Heart Renal Outcomes Network (NEPHRON) study to describe multi-centre peritoneal catheter use after STAT category 3-5 neonatal cardiac surgery using cardiopulmonary bypass. Patient characteristics and acute kidney injury/fluid outcomes for six post-operative days are described among three cohorts: peritoneal catheter with dialysis, peritoneal catheter with passive drainage, and no peritoneal catheter. RESULTS: Of 1490 neonates, 471 (32%) had an intraoperative peritoneal catheter placed; 177 (12%) received prophylactic dialysis and 294 (20%) received passive drainage. Sixteen (73%) centres used peritoneal catheter at some frequency, including six centres in >50% of neonates. Four centres utilised prophylactic peritoneal dialysis. Time to post-operative dialysis initiation was 3 hours [1, 5] with the duration of 56 hours [37, 90]; passive drainage cohort drained for 92 hours [64, 163]. Peritoneal catheter were more common among patients receiving pre-operative mechanical ventilation, single ventricle physiology, and higher complexity surgery. There was no association with adverse events. Serum creatinine and daily fluid balance were not clinically different on any post-operative day. Mortality was similar. CONCLUSIONS: In neonates undergoing complex cardiac surgery, peritoneal catheter use is not rare, with substantial variability among centres. Peritoneal catheters are used more commonly with higher surgical complexity. Adverse event rates, including mortality, are not different with peritoneal catheter use. Fluid overload and creatinine-based acute kidney injury rates are not different in peritoneal catheter cohorts.

A novel acute kidney injury scoring system for renal and clinical outcomes in pediatric heart transplant patients.

BACKGROUND: The development of acute kidney injury (AKI) has been associated with worse outcomes in children after heart transplantation. Our study compares the application of a cumulative six-point Kidney Diseases Improving Global Outcomes (KDIGO) AKI scoring system, utilizing both creatinine and urine output criteria that we term as the AKI-6 criteria, to traditional AKI staging as a predictor for clinical and renal outcomes in the pediatric heart transplant recipients. METHODS: We conducted a retrospective single-center chart review on 155 pediatric patients who underwent heart transplantation from May 2014 to December 2021. The primary independent variable was the presence of severe AKI. Severe AKI by KDIGO was defined as Stage ≥2, whereas severe AKI by AKI-6 was defined as cumulative scores ≥4 or Stage 3 AKI based on either KDIGO criterion alone. Primary outcomes included actuarial survival and renal dysfunction by 1-year post-transplant, defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2 . RESULTS: In total, 140 (90%) patients developed AKI; 98 (63%) patients developed severe AKI by KDIGO, and 60 (39%) by AKI-6. Severe AKI by AKI-6 was associated with worse actuarial survival following heart transplantation compared with KDIGO (p = 0.01). Of the 143 patients with 1-year creatinine data, 6 (11%) patients out of 54 with severe AKI by AKI-6 had evidence of renal dysfunction (p = 0.01), compared with 6 (7%) patients out of 88 by KDIGO (p = 0.3). CONCLUSIONS: AKI-6 scoring provides greater prognostic utility for actuarial survival and renal dysfunction by 1-year post-heart transplantation in pediatric patients than traditional KDIGO staging.

Variation in hospital costs and resource utilisation after congenital heart surgery.

BACKGROUND: Children undergoing cardiac surgery have overall improving survival, though they consume substantial resources. Nationwide inpatient cost estimates and costs at longitudinal follow-up are lacking. METHODS: Retrospective cohort study of children <19 years of age admitted to Pediatric Health Information System administrative database with an International Classification of Diseases diagnosis code undergoing cardiac surgery. Patients were grouped into neonates (≤30 days of age), infants (31-365 days of age), and children (>1 year) at index procedure. Primary and secondary outcomes included hospital stay and hospital costs at index surgical admission and 1- and 5-year follow-up. RESULTS: Of the 99,670 cohort patients, neonates comprised 27% and had the highest total hospital costs, though daily hospital costs were lower. Mortality declined (5.6% in 2004 versus 2.5% in 2015, p < 0.0001) while inpatient costs rose (5% increase/year, p < 0.0001). Neonates had greater index diagnosis complexity, greater inpatient costs, required the greatest ICU resources, pharmacotherapy, and respiratory therapy. We found no relationship between hospital surgical volume, mortality, and hospital costs. Neonates had higher cumulative hospital costs at 1- and 5-year follow-up compared to infants and children. CONCLUSIONS: Inpatient hospital costs rose during the study period, driven primarily by longer stay. Neonates had greater complexity index diagnosis, required greater hospital resources, and have higher hospital costs at 1 and 5 years compared to older children. Surgical volume and in-hospital mortality were not associated with costs. Further analyses comprising merged clinical and administrative data are necessary to identify longer stay and cost drivers after paediatric cardiac surgery.

Indexed oxygen delivery during pediatric cardiopulmonary bypass is a modifiable risk factor for postoperative acute kidney injury.

BACKGROUND: Acute kidney injury after pediatric cardiac surgery is a common complication with few established modifiable risk factors. We sought to characterize whether indexed oxygen delivery during cardiopulmonary bypass was associated with postoperative acute kidney injury in a large pediatric cohort. METHODS: This was a retrospective analysis of patients under 1 year old undergoing cardiac surgery with cardiopulmonary bypass between January 1, 2013, and January 1, 2020. Receiver operating characteristic curves across values ranging from 260 to 400 mL/min/m2 were used to identify the indexed oxygen delivery most significantly associated with acute kidney injury risk. RESULTS: We included 980 patients with acute kidney injury occurring in 212 (21.2%). After adjusting for covariates associated with acute kidney injury, an indexed oxygen delivery threshold of 340 mL/min/m2 predicted acute kidney injury in STAT 4 and 5 neonates (area under the curve = 0.66, 95% CI = 0.60 - 0.72, sensitivity = 56.1%, specificity = 69.4%). An indexed oxygen delivery threshold of 400 mL/min/m2 predicted acute kidney injury in STAT 1-3 infants (area under the curve = 0.65, 95% CI = 0.58 - 0.72, sensitivity = 52.6%, specificity = 74.6%). CONCLUSION: Indexed oxygen delivery during cardiopulmonary bypass is a modifiable variable independently associated with postoperative acute kidney injury in specific pediatric populations. Strategies aimed at maintaining oxygen delivery greater than 340 mL/min/m2 in complex neonates and greater than 400 mL/min/m2 in infants may reduce the occurrence of postoperative acute kidney injury in the pediatric population.

Epidemiology of Acute Kidney Injury After Neonatal Cardiac Surgery: A Report From the Multicenter Neonatal and Pediatric Heart and Renal Outcomes Network.

OBJECTIVES: Cardiac surgery-associated acute kidney injury occurs commonly following congenital heart surgery and is associated with adverse outcomes. This study represents the first multicenter study of neonatal cardiac surgery-associated acute kidney injury. We aimed to describe the epidemiology, including perioperative predictors and associated outcomes of this important complication. DESIGN: This Neonatal and Pediatric Heart and Renal Outcomes Network study is a multicenter, retrospective cohort study of consecutive neonates less than 30 days. Neonatal modification of The Kidney Disease Improving Global Outcomes criteria was used. Associations between cardiac surgery-associated acute kidney injury stage and outcomes (mortality, length of stay, and duration of mechanical ventilation) were assessed through multivariable regression. SETTING: Twenty-two hospitals participating in Pediatric Cardiac Critical Care Consortium. PATIENTS: Twenty-two-thousand forty neonates who underwent major cardiac surgery from September 2015 to January 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cardiac surgery-associated acute kidney injury occurred in 1,207 patients (53.8%); 983 of 1,657 in cardiopulmonary bypass patients (59.3%) and 224 of 583 in noncardiopulmonary bypass patients (38.4%). Seven-hundred two (31.3%) had maximum stage 1, 302 (13.5%) stage 2, 203 (9.1%) stage 3; prevalence of cardiac surgery-associated acute kidney injury peaked on postoperative day 1. Cardiac surgery-associated acute kidney injury rates varied greatly (27-86%) across institutions. Preoperative enteral feeding (odds ratio = 0.68; 0.52-0.9) and open sternum (odds ratio = 0.76; 0.61-0.96) were associated with less cardiac surgery-associated acute kidney injury; cardiopulmonary bypass was associated with increased cardiac surgery-associated acute kidney injury (odds ratio = 1.53; 1.01-2.32). Duration of cardiopulmonary bypass was not associated with cardiac surgery-associated acute kidney injury in the cardiopulmonary bypass cohort. Stage 3 cardiac surgery-associated acute kidney injury was independently associated with hospital mortality (odds ratio = 2.44; 1.3-4.61). No cardiac surgery-associated acute kidney injury stage was associated with duration of mechanical ventilation or length of stay. CONCLUSIONS: Cardiac surgery-associated acute kidney injury occurs frequently after neonatal cardiac surgery in both cardiopulmonary bypass and noncardiopulmonary bypass patients. Rates vary significantly across hospitals. Only stage 3 cardiac surgery-associated acute kidney injury is associated with mortality. Cardiac surgery-associated acute kidney injury was not associated with any other outcomes. Kidney Disease Improving Global Outcomes criteria may not precisely define a clinically meaningful renal injury phenotype in this population.

Higher total ultrafiltration volume during cardiopulmonary bypass-assisted infant cardiac surgery is associated with acute kidney injury and fluid overload.

BACKGROUND: Ultrafiltration (UF) is used for fluid removal during and after infant cardiopulmonary bypass (CPB) surgery to reduce fluid overload. Excessive UF may have the opposite of its intended effect, resulting in acute kidney injury (AKI), oliganuria, and fluid retention. METHODS: This is a single-center, retrospective review of infants treated with conventional and/or modified UF during CPB surgery. UF volume was indexed to weight. AKI was defined using serum creatinine "Kidney Disease Improving Global Outcome (KDIGO)" criteria. Fluid balance was defined according to: [Formula: see text]. Peak fluid overload was determined on postoperative day 3. Multivariable logistic regression adjusted for multiple covariates was used to explore associations with UF, AKI, and fluid overload. RESULTS: Five hundred thirty subjects < 1 year of age underwent CPB-assisted congenital heart surgery with UF. Sixty-four (12%) developed postoperative AKI. On multivariable regression, higher indexed total UF volume was associated with increased AKI risk (OR 1.11, 95% CI=1.04-1.19, p = 0.003). UF volume > 119.9 mL/kg did not reduce peak fluid overload. Subjects with AKI took longer to reach a negative fluid balance (2 vs. 3 days, p = 0.04). Those with more complex surgery were at highest AKI risk (STAT 3 [25-75 percentile: 3-4] in AKI group versus STAT 3 [25-75 percentile: 2-4] in non-AKI group, p = 0.05). AKI was reduced in subjects undergoing more complex surgery and treated with UF volume < 119.9 mL/kg. CONCLUSIONS: Judicious use of UF in more complex congenital cardiac surgery reduces the risk of AKI.

Hospital-Acquired Infection in Pediatric Subjects With Congenital Heart Disease Postcardiotomy Supported on Extracorporeal Membrane Oxygenation.

OBJECTIVE: To determine prevalence of and risk factors for infection in pediatric subjects with congenital heart disease status postcardiotomy supported on extracorporeal membrane oxygenation, as well as outcomes of these subjects. DESIGN: Retrospective cohort from the Extracorporeal Life Support Organization. SETTING: U.S. and international medical centers providing care to children with congenital heart disease status postcardiotomy. PATIENTS: Critically ill pediatric subjects less than 8 years old admitted to medical centers between January 1, 2013, and December 31, 2015, who underwent cardiac surgery for congenital heart disease and required extracorporeal membrane oxygenation support within the first 14 postoperative days. Subjects were excluded if they underwent orthotopic heart transplantation, required preoperative extracorporeal membrane oxygenation, and had more than one postoperative extracorporeal membrane oxygenation run. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 1,314 extracorporeal membrane oxygenation subject encounters in the Extracorporeal Life Support Organization registry met inclusion criteria. Neonates comprised 53% (n = 696) of the cohort, whereas infants made up 33% (n = 435). Of the 994 subjects with Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery categorizable surgery, 33% (n = 325) were in Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category 4 and 23% (n = 231) in Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category 5. While on extracorporeal membrane oxygenation, 229 subjects (17%) acquired one or more extracorporeal membrane oxygenation-related infections, which represents an occurrence rate of 67 infections per 1,000 extracorporeal membrane oxygenation days. Gram-negative (62%) and Gram-positive (42%) infections occurred most commonly. Forty percent had positive blood cultures. Infants and children were at higher infection risk compared with neonatal subjects; subjects undergoing less complex surgery had higher infection rates. Unadjusted survival to hospital discharge was lower in infected subjects compared with noninfected subjects (43% vs 51%; p = 0.01). After adjusting for confounders via propensity matching, we identified no significant mortality difference between infected and noninfected subjects. CONCLUSIONS: Neonatal and pediatric subjects in this study have a high rate of acquired infection. Infants and children were at higher infection risk compared with neonatal subjects. There was not, however, a significant association between extracorporeal membrane oxygenation-related infection and survival to hospital discharge after propensity matching.

Pulse Oximetry Screening Has Not Changed Timing of Diagnosis or Mortality of Critical Congenital Heart Disease.

This study evaluates the effectiveness of mandatory pulse oximetry screening. The objective is to evaluate whether mandatory pulse oximetry testing had decreased the late critical congenital heart disease (CCHD) diagnosis rate and reduced mortality in neonatal subjects. This was a single center, retrospective cohort study comparing the timing of diagnosis of CCHD between neonates undergoing cardiac surgery in 2009-2010, prior to mandatory pulse oximetry screening, and neonates in 2015-2016, after mandatory pulse oximetry screening was instituted. Follow-up was for 1 year. We defined CCHD as lesions requiring surgical correction within 30 days of life. Exclusions included: pacemaker insertions, vascular ring divisions, closure of patent ductus arteriosus, arterial cutdown, or extracorporeal membrane oxygenation cannulation without structural heart disease as the sole procedure, or if subjects were born at home. Infants diagnosed prior to discharge from birth hospital were defined as early postnatal; late postnatal subjects were diagnosed after birth hospital discharge. In-hospital mortality and 1-year mortality were measured. A total of 527 neonates were included; 251 (47.6%) comprised the pre-mandatory pulse oximetry screening cohort (2009-2010). Only 3.6% of the 2009-2010 cohort and 4.3% of the 2015-2016 cohort were diagnosed late (p = 0.66). One-year mortality decreased during the study period (17.2% in 2009-2010 vs 10.5% in 2015-2016, p = 0.03). There were no deaths in the late CCHD diagnosis groups. Mandatory pulse oximetry screening legislation has not changed the late postnatal diagnosis rate at our institution. Mortality for neonatal CCHD has declined, but this decline is not attributable to mandatory pulse oximetry screening.

Red cell transfusion practices after stage 1 palliation: a survey of practitioners from the Pediatric Cardiac Intensive Care Society.

INTRODUCTION: Neonates may require increased red cell mass to optimise oxygen content after stage 1 palliation; however, data informing transfusion practices are limited. We hypothesise there is a patient-, provider-, and institution-based heterogeneity in red cell transfusion decision-making after stage 1 palliation. METHODS: We conducted an online survey of Pediatric Cardiac Intensive Care Society practitioners in 2016. Respondents answered scenario-based questions that defined transfusion indications and identified haematocrit transfusion thresholds. Respondents were divided into restrictive and liberal groups based on a haematocrit score. Fisher's exact test was used to determine the associations between transfusion likelihood and patient, provider, and institutional characteristics. Bonferroni correction was applied to adjust the p-value to 0.004 for multiple comparisons. RESULTS: There was a 21% response rate (116 responses). Most were male (58.6%), attending physicians (85.3%) with >5 year of intensive care experience (88.7%) and subspeciality training in critical care medicine (47.4%). The majority of institutions were academic (96.6%), with a separate cardiac ICU (86.2%), and performed >10 stage 1 palliation cases annually (68.1%). After Bonferroni correction, there were no significant patient, respondent, or institutional differences between the restrictive and liberal groups. No respondent or institutional characteristics influenced transfusion decision-making after stage 1 palliation. CONCLUSIONS: Decision-making around red cell transfusion after stage 1 palliation is heterogeneous. We found no clear relationships between patient, respondent, or institutional characteristics and transfusion decision-making among surveyed respondents. Given the lack of existing data informing red cell transfusion after stage 1 palliation, further studies are necessary to inform evidence-based guidelines.

Neonatal and Paediatric Heart and Renal Outcomes Network: design of a multi-centre retrospective cohort study.

BACKGROUND: Cardiac surgery-associated acute kidney injury is common. In order to improve our understanding of acute kidney injury, we formed the multi-centre Neonatal and Pediatric Heart and Renal Outcomes Network. Our main goals are to describe neonatal kidney injury epidemiology, evaluate variability in diagnosis and management, identify risk factors, investigate the impact of fluid overload, and explore associations with outcomes. METHODS: The Neonatal and Pediatric Heart and Renal Outcomes Network collaborative includes representatives from paediatric cardiac critical care, cardiology, nephrology, and cardiac surgery. The collaborative sites and infrastructure are part of the Pediatric Cardiac Critical Care Consortium. An acute kidney injury module was developed and merged into the existing infrastructure. A total of twenty-two participating centres provided data on 100-150 consecutive neonates who underwent cardiac surgery within the first 30 post-natal days. Additional acute kidney injury variables were abstracted by chart review and merged with the corresponding record in the quality improvement database. Exclusion criteria included >1 operation in the 7-day study period, pre-operative renal replacement therapy, pre-operative serum creatinine >1.5 mg/dl, and need for extracorporeal support in the operating room or within 24 hours after the index operation. RESULTS: A total of 2240 neonatal patients were enrolled across 22 centres. The incidence of acute kidney injury was 54% (stage 1 = 31%, stage 2 = 13%, and stage 3 = 9%). CONCLUSIONS: Neonatal and Pediatric Heart and Renal Outcomes Network represents the largest multi-centre study of neonatal kidney injury. This new network will enhance our understanding of kidney injury and its complications.

Acute Kidney Injury After Pediatric Cardiac Surgery: A Secondary Analysis of the Safe Pediatric Euglycemia After Cardiac Surgery Trial.

OBJECTIVES: To understand the effect of tight glycemic control on cardiac surgery-associated acute kidney injury. DESIGN: Secondary analysis of data from the Safe Pediatric Euglycemia after Cardiac Surgery trial of tight glycemic control versus standard care. SETTING: Pediatric cardiac ICUs at University of Michigan, C.S. Mott Children's Hospital, and Boston Children's Hospital. PATIENTS: Children 0-36 months old undergoing congenital cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cardiac surgery-associated acute kidney injury was assigned using the Acute Kidney Injury Network criteria with the modification that a greater than 0.1 mg/dL increase in serum creatinine was required to assign cardiac surgery-associated acute kidney injury. We explored associations between cardiac surgery-associated acute kidney injury and tight glycemic control and clinical outcomes. Of 799 patients studied, cardiac surgery-associated acute kidney injury occurred in 289 patients (36%), most of whom had stage II or III disease (72%). Cardiac surgery-associated acute kidney injury rates were similar between treatment groups (36% vs 36%; p = 0.99). Multivariable modeling showed that patients with cardiac surgery-associated acute kidney injury were younger (p = 0.002), underwent more complex surgery (p = 0.005), and had longer cardiopulmonary bypass times (p = 0.002). Cardiac surgery-associated acute kidney injury was associated with longer mechanical ventilation and ICU and hospital stays and increased mortality. Patients at University of Michigan had higher rates of cardiac surgery-associated acute kidney injury compared with Boston Children's Hospital patients (66% vs 15%; p < 0.001), but University of Michigan patients with cardiac surgery-associated acute kidney injury had shorter time to extubation and ICU and hospital stays compared with Boston Children's Hospital patients. CONCLUSIONS: Tight glycemic control did not reduce the cardiac surgery-associated acute kidney injury rate in this trial cohort. We observed significant differences in cardiac surgery-associated acute kidney injury rates between the two study sites, and there was a differential effect of cardiac surgery-associated acute kidney injury on clinical outcomes by site. These findings warrant further investigation to identify causal variation in perioperative practices that affect cardiac surgery-associated acute kidney injury epidemiology.

An evaluation of the outcomes associated with peritoneal catheter use in neonates undergoing cardiac surgery: A multicenter study.

Objective: The study objective was to determine if intraoperative peritoneal catheter placement is associated with improved outcomes in neonates undergoing high-risk cardiac surgery with cardiopulmonary bypass. Methods: This propensity score-matched retrospective study used data from 22 academic pediatric cardiac intensive care units. Consecutive neonates undergoing Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category 3 to 5 cardiac surgery with cardiopulmonary bypass at centers participating in the NEonatal and Pediatric Heart Renal Outcomes Network collaborative were studied to determine the association of the use of an intraoperative placed peritoneal catheter for dialysis or passive drainage with clinical outcomes, including the duration of mechanical ventilation. Results: Among 1490 eligible neonates in the NEonatal and Pediatric Heart Renal Outcomes Network dataset, a propensity-matched analysis was used to compare 395 patients with peritoneal catheter placement with 628 patients without peritoneal catheter placement. Time to extubation and most clinical outcomes were similar. Postoperative length of stay was 5 days longer in the peritoneal catheter placement cohort (17 vs 22 days, P = .001). There was a 50% higher incidence of moderate to severe acute kidney injury in the no-peritoneal catheter cohort (12% vs 18%, P = .02). Subgroup analyses between specific treatments and in highest risk patients yielded similar associations. Conclusions: This study does not demonstrate improved outcomes among neonates with placement of a peritoneal catheter during cardiac surgery. Outcomes were similar apart from longer hospital stay in the peritoneal catheter cohort. The no-peritoneal catheter cohort had a 50% higher incidence of moderate to severe acute kidney injury (12% vs 18%). This analysis does not support indiscriminate peritoneal catheter use, although it may support the utility for postoperative fluid removal among neonates at risk for acute kidney injury. A multicenter controlled trial may better elucidate peritoneal catheter effects.

Hemodynamic and Echocardiographic Predictors of Mortality in Pediatric Patients on Venoarterial Extracorporeal Membrane Oxygenation: A Multicenter Investigation.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (ECMO) supports patients with advanced cardiac dysfunction; however, mortality occurs in a significant subset of patients. The authors performed a multicenter, prospective study to determine hemodynamic and echocardiographic predictors of mortality in children placed on ECMO for cardiac support. METHODS: Over 8 years, six heart centers prospectively assessed echocardiographic and hemodynamic variables on full and minimum ECMO flow. Sixty-three patients were enrolled, ranging in age from 1 day to 16 years. Hemodynamic measurements included heart rate, vasoactive inotropic score, arteriovenous oxygen difference, pulse pressure, and lactate. Echocardiographic variables included shortening fraction, ejection fraction (EF), right ventricular fractional area change, outflow tract Doppler-derived stroke distance (velocity-time integral [VTI]), and degree of atrioventricular valve regurgitation. Patients were stratified into two groups: those who were able to wean within 48 hours of assessment and survived without ventricular assist devices or orthotopic heart transplantation (successful wean group) and those with unsuccessful weaning. For each patient, variables were compared between full and minimum ECMO flow for each group. RESULTS: Thirty-eight patients (60%) formed the unsuccessful group (two with ventricular assist devices, four with orthotopic heart transplantation, 24 deaths), and 25 constituted the successful wean group. At minimum flow, higher EF (53 ± 16% vs 40 ± 20%, P = .0094), less mitral regurgitation (0.8 ± 0.9 vs 1.4 ± 0.9, P = .0329), and lower central venous pressure (12.0 ± 3.9 vs 14.7 ± 5.4 mm Hg), along with higher VTI (9.0 ± 2.9 vs 6.8 ± 3.7 cm, P = .0154), correlated successful weaning. A longer duration of ECMO (8 vs 5 days, P < .0002) was associated with unsuccessful weaning. Multivariate logistic regression predicted minimum-flow EF and VTI to independently predict successful weaning with cutoff values by receiver operating characteristic analysis of EF > 41% (area under the curve, 0.712; P = .0005) and VTI > 7.9 cm (area under the curve, 0.729; P = .0010). CONCLUSIONS: Diminished VTI or EF during ECMO weaning predicts the need for orthotopic heart transplantation or ventricular assist device support or death in children on ECMO for cardiac dysfunction. Increased postwean central venous pressure or mitral regurgitation along with a prolonged ECMO course also predicted these adverse outcomes. These measurements should be used to help discriminate which patients will require alternative methods of circulatory support for survival.

Fluid Accumulation After Neonatal Congenital Cardiac Operation: Clinical Implications and Outcomes.

BACKGROUND: This study was conducted to determine the association between fluid balance metrics and mortality and other postoperative outcomes after neonatal cardiac operation in a contemporary multicenter cohort. METHODS: This was an observational cohort study across 22 hospitals in neonates (≤30 days) undergoing cardiac operation. We explored overall percentage fluid overload, postoperative day 1 percentage fluid overload, peak percentage fluid overload, and time to first negative daily fluid balance. The primary outcome was in-hospital mortality. Secondary outcomes included postoperative duration of mechanical ventilation and intensive care unit (ICU) and hospital length of stay. Multivariable logistic or negative binomial regression was used to determine independent associations between fluid overload variables and each outcome. RESULTS: The cohort included 2223 patients. In-hospital mortality was 3.9% (n = 87). Overall median peak percentage fluid overload was 4.9% (interquartile range, 0.4%-10.5%). Peak percentage fluid overload and postoperative day 1 percentage fluid overload were not associated with primary or secondary outcomes. Hospital resource utilization increased on each successive day of not achieving a first negative daily fluid balance and was characterized by longer duration of mechanical ventilation (incidence rate ratio, 1.11; 95% CI, 1.08-1.14), ICU length of stay (incidence rate ratio, 1.08; 95% CI, 1.03-1.12), and hospital length of stay (incidence rate ratio, 1.09; 95% CI, 1.05-1.13). CONCLUSIONS: Time to first negative daily fluid balance, but not percentage fluid overload, is associated with improved postoperative outcomes in neonates after cardiac operation. Specific treatments to achieve an early negative fluid balance may decrease postoperative care durations.

Noncompaction of the left ventricular myocardium in a boy with a novel chromosome 8p23.1 deletion.

Interstitial deletion of chromosome 8p23.1 has been reported in patients with congenital heart defects, including atrial and ventricular septal defects, pulmonary stenosis, and complex cyanotic heart defects. GATA4, a zinc-finger transcription factor gene, has been localized to this region. GATA4 interacts with additional transcription factors in the embryogenesis of the primitive heart tube. Mutations in GATA4 are thought to be responsible for the congenital heart defects reported in association with this chromosomal deletion, and several familial point mutations leading to amino acid substitutions have also been identified. Left ventricular noncompaction (LVNC) is a clinically heterogeneous disorder characterized by LV myocardial trabeculations and intertrabecular recesses that communicate with the LV cavity. Patients may be asymptomatic or may present with evidence of severely depressed LV systolic and diastolic function. The LV may be dilated or hypertrophied, and clinical expression may be undulating. Several genetic causes of LVNC have been reported, with variable modes of inheritance, including autosomal dominant and X-linked inheritance, but relatively few responsible genes have been identified. A 12-year-old boy with a history of acute lymphoblastic leukemia, dysmorphic features, and LVNC with preserved LV systolic function was referred to the Cardiovascular Genetics Clinic at our institution. The patient was asymptomatic in terms of cardiovascular function. Chromosome microarray testing revealed an interstitial deletion in the region of 8p23.1 containing GATA4. LVNC has not been reported previously in association with this chromosome deletion. Further investigation into the role of GATA4 in patients with LVNC is warranted.

Development of Care Curves Following the Stage 1 Palliation: A Comparison of Intensive Care Among 5 Centers.

Background Comparison of care among centers is currently limited to major end points, such as mortality, length of stay, or complication rates. Creating "care curves" and comparing individual elements of care over time may highlight modifiable differences in intensive care among centers. Methods and Results We performed an observational retrospective study at 5 centers in the United States to describe key elements of postoperative care following the stage 1 palliation. A consecutive sample of 502 infants undergoing stage 1 palliation between January 2009 and December 2018 were included. All electronic health record entries relating to mandatory mechanical ventilator rate, opioid administration, and fluid intake/outputs between postoperative days (POD) 0 to 28 were extracted from each institution's data warehouse. During the study period, 502 patients underwent stage 1 palliation among the 5 centers. Patients were weaned to a median mandatory mechanical ventilator rate of 10 breaths/minute by POD 4 at Center 5 but not until POD 7 to 8 at Centers 1 and 2. Opioid administration peaked on POD 2 with extreme variance (median 6.9 versus 1.6 mg/kg per day at Center 3 versus Center 2). Daily fluid balance trends were variable: on POD 3 Center 1 had a median fluid balance of -51 mL/kg per day, ranging between -34 to 19 mL/kg per day among remaining centers. Intercenter differences persist after adjusting for patient and surgical characteristics (P<0.001 for each end point). Conclusions It is possible to detail and compare individual elements of care over time that represent modifiable differences among centers, which persist even after adjusting for patient factors. Care curves may be used to guide collaborative quality improvement initiatives.

Red Blood Cell Transfusion After Stage I Palliation Is Associated With Worse Clinical Outcomes.

Background Packed red blood cell transfusion may improve oxygen content in single-ventricle neonates, but its effect on clinical outcomes after Stage 1 palliation is unknown. Methods and Results Retrospective multicenter analysis of packed red blood cell transfusion exposures in neonates after Stage 1 palliation, excluding those with intraoperative mortality or need for extracorporeal membrane oxygenation. Transfusion practice variability was assessed, and multivariable regression used to identify transfusion risk factors. After propensity score adjustment for severity of illness, clinical outcomes were compared between transfused and nontransfused subjects. Of 396 subjects, 323 (82%) received 930 postoperative red blood cell transfusions. Packed red blood cell volume (median 9-42 mL/kg [P<0.0001]), donor exposures (1-2 [P<0.0001]), transfusion number (1-3 [P<0.0001]), and pretransfusion hemoglobin (12.1-13 g/dL, P=0.0049) varied between sites. Cyanosis (P=0.02), chest tube output (P=0.0003), and delayed sternal closure (P=0.0033) increased transfusion risk. Transfusion was associated with prolonged mechanical ventilation (6 [interquartile range 4, 12] versus 3 [1, 5] days, P=0.02) and intensive care unit stay (19 [12, 33] versus 9 [6, 19] days, P=0.016). When stratified by number of transfusions (0, 1, or >1), duration of mechanical ventilation (3 [1, 5] versus 4 [3, 6] versus 9 [5, 16] days [P<0.0001]) and intensive care unit stay (9 [6, 19] versus 13 [8, 25] versus 21 [13, 38] days [P<0.0001]) increased for those transfused more than once. Most subjects who died were transfused, though the association with mortality was not significant. Conclusions Packed red blood cell transfusion after Stage 1 palliation is common, and transfusion practice is variable. Transfusion is a significant predictor of longer intensive care unit stay and mechanical ventilation. Further studies to define evidence-based transfusion thresholds are warranted.