Assessing enrollment of eligible infants in the national pediatric cardiology quality improvement collaborative (NPC-QIC) through linkage to the pediatric cardiac critical care consortium (PC4) registry.

BACKGROUND: The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) lacks a rigorous enrollment audit process, unlike other collaborative networks. Most centers require individual families to consent to participate. It is unknown whether there is variation across centers or biases in enrollment. METHODS: We used the Pediatric Cardiac Critical Care Consortium (PC4) registry to assess enrollment rates in NPC-QIC for those centers participating in both registries using indirect identifiers (date of birth, date of admission, gender, and center) to match patient records. All infants born 1/1/2018-12/31/2020 and admitted 30 days of life were eligible. In PC4, all infants with a fundamental diagnosis of hypoplastic left heart or variant or who underwent a surgical or hybrid Norwood or variant were eligible. Standard descriptive statistics were used to describe the cohort and center match rates were plotted on a funnel chart. RESULTS: Of 898 eligible NPC-QIC patients, 841 were linked to 1,114 eligible PC4 patients (match rate 75.5%) in 32 centers. Match rates were lower in patients of Hispanic/Latino ethnicity (66.1%, p = 0.005), and those with any specified chromosomal abnormality (57.4%, p = 0.002), noncardiac abnormality (67.8%, p = 0.005), or any specified syndrome (66.5%, p = 0.001). Match rates were lower for patients who transferred to another hospital or died prior to discharge. Match rates varied from 0 to 100% across centers. CONCLUSIONS: It is feasible to match patients between the NPC-QIC and PC4 registries. Variation in match rates suggests opportunities for improvement in NPC-QIC patient enrollment.

Development of the data registry for the Cardiac Neurodevelopmental Outcome Collaborative.

Children with congenital heart disease (CHD) can face neurodevelopmental, psychological, and behavioural difficulties beginning in infancy and continuing through adulthood. Despite overall improvements in medical care and a growing focus on neurodevelopmental screening and evaluation in recent years, neurodevelopmental disabilities, delays, and deficits remain a concern. The Cardiac Neurodevelopmental Outcome Collaborative was founded in 2016 with the goal of improving neurodevelopmental outcomes for individuals with CHD and pediatric heart disease. This paper describes the establishment of a centralised clinical data registry to standardize data collection across member institutions of the Cardiac Neurodevelopmental Outcome Collaborative. The goal of this registry is to foster collaboration for large, multi-centre research and quality improvement initiatives that will benefit individuals and families with CHD and improve their quality of life. We describe the components of the registry, initial research projects proposed using data from the registry, and lessons learned in the development of the registry.

Quality of life after Ross procedure in children.

INTRODUCTION: Health-related quality of life in children who have undergone the Ross procedure has not been well characterised. The aim of this study was to characterise health-related quality of life in this cohort and compare to children with other CHD. METHOD: In this cross sectional, single-centre study, health-related quality of life was assessed in patients who underwent a non-neonatal Ross procedure using the Pediatric Quality of Life Inventory. Ross cohort scores were compared with healthy norms, patients with CHD requiring no surgical intervention or had curative surgery (Severity 2, S2) and patients who were surgically repaired with ≥1 surgical procedure and with significant residual lesion or need for additional surgery (Severity 3, S3). Associations between Pediatric Quality of Life Inventory score and patient factors were also examined. RESULTS: 68 patients completed surveys. Nearly one-sixth of patients had overall scores below the cut-off for at-risk status for impaired health-related quality of life. There was no difference in overall health-related quality of life score between the Ross cohort and healthy children (p = 0.56) and S2 cohort (p = 0.97). Health-related quality of life was significantly higher in the Ross cohort compared to S3 cohort (p = 0.02). This difference was driven by a higher psychosocial health-related quality of life in the Ross cohort as compared to S3 cohort (p = 0.007). Anxiety scores were significantly worse in the Ross cohort compared to both S2 (p = 0.001) and S3 (p = 0.0017), respectively. CONCLUSION: Children who have undergone a Ross procedure report health-related quality of life equivalent to CHD not requiring therapy and superior to CHD with residual lesions. Despite these reassuring results, providers should be aware of potential anxiety among Ross patients.

Assessing data accuracy in a large multi-institutional quality improvement registry: an update from the Pediatric Cardiac Critical Care Consortium (PC4).

BACKGROUND: The Pediatric Cardiac Critical Care Consortium (PC4) is a multi-institutional quality improvement registry focused on the care delivered in the cardiac ICU for patients with CHD and acquired heart disease. To assess data quality, a rigorous procedure of data auditing has been in place since the inception of the consortium. MATERIALS AND METHODS: This report describes the data auditing process and quantifies the audit results for the initial 39 audits that took place after the transition from version one to version two of the registry's database. RESULTS: In total, 2219 total encounters were audited for an average of 57 encounters per site. The overall data accuracy rate across all sites was 99.4%, with a major discrepancy rate of 0.52%. A passing score is based on an overall accuracy of >97% (achieved by all sites) and a major discrepancy rate of <1.5% (achieved by 38 of 39 sites, with 35 of 39 sites having a major discrepancy rate of <1%). Fields with the highest discrepancy rates included arrhythmia type, cardiac arrest count, and current surgical status. CONCLUSIONS: The extensive PC4 auditing process, including initial and routinely scheduled follow-up audits of every participating site, demonstrates an extremely high level of accuracy across a broad array of audited fields and supports the continued use of consortium data to identify best practices in paediatric cardiac critical care.

Spillover of Early Extubation Practices From the Pediatric Heart Network Collaborative Learning Study.

OBJECTIVES: The Pediatric Heart Network Collaborative Learning Study used collaborative learning strategies to implement a clinical practice guideline that increased rates of early extubation after infant repair of tetralogy of Fallot and coarctation of the aorta. We assessed early extubation rates for infants undergoing cardiac surgeries not targeted by the clinical practice guideline to determine whether changes in extubation practices spilled over to care of other infants. DESIGN: Observational analyses of site's local Society of Thoracic Surgeons Congenital Heart Surgery Database and Pediatric Cardiac Critical Care Consortium Registry. SETTING: Four Pediatric Heart Network Collaborative Learning Study active-site hospitals. PATIENTS: Infants undergoing ventricular septal defect repair, atrioventricular septal defect repair, or superior cavopulmonary anastomosis (lower complexity), and arterial switch operation or isolated aortopulmonary shunt (higher complexity). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Aggregate outcomes were compared between the 12 month pre-clinical practice guideline and 12 months after study completion (Follow Up). In infants undergoing lower complexity surgeries, early extubation increased during Follow Up compared with Pre-Clinical Practice Guideline (30.2% vs 18.8%, p = 0.006), and hours to initial postoperative extubation decreased. We observed variation in these outcomes by surgery type, with only ventricular septal defect repair associated with a significant increase in early extubation during Follow Up compared with Pre-Clinical Practice Guideline (47% vs 26%, p = 0.006). Variation by study site was also seen, with only one hospital showing an increase in early extubation. In patients undergoing higher complexity surgeries, there was no difference in early extubation or hours to initial extubation between the study eras. CONCLUSIONS: We observed spillover of extubation practices promoted by the Collaborative Learning Study clinical practice guideline to lower complexity operations not included in the original study that was sustainable 1 year after study completion, though this effect differed across sites and operation subtypes. No changes in postoperative extubation outcomes following higher complexity surgeries were seen. The significant variation in outcomes by site suggests that center-specific factors may have influenced spillover of clinical practice guideline practices.

Central Venous Catheter Utilization and Complications in the Pediatric Cardiac ICU: A Report From the Pediatric Cardiac Critical Care Consortium (PC4).

OBJECTIVES: Current central venous catheter utilization in patients within pediatric cardiac ICUs is not well elucidated. We aim to describe current use of central venous catheters in a multi-institutional cohort and to explore the prevalence and risk factors for central line-associated thrombosis and central line-associated bloodstream infections. DESIGN: Observational analysis. SETTING: Pediatric Cardiac Critical Care Consortium hospitals. PATIENTS: Hospitalizations with at least one cardiac ICU admission from October 2013 to July 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 17,846 hospitalizations and 69% included greater than or equal to one central venous catheter. Central venous catheter use was higher in younger patients (86% neonates). Surgical hospitalizations included at least one central venous catheter 88% of the time compared with 35% of medical hospitalizations. The most common location for central venous catheters was internal jugular (46%). Central venous catheters were in situ a median of 4 days (interquartile range, 2-10). There were 248 hospitalizations (2% overall, 1.8% medical, and 2.1% surgical) with at least one central line-associated thrombosis (271 total thromboses). Thrombosis was diagnosed at a median of 7 days (interquartile range, 4-14) after catheter insertion. There were 127 hospitalizations (1% overall, 1.4% medical, and 1% surgical) with at least one central line-associated bloodstream infection (136 total infections) with no association with catheter type or location. Central line-associated bloodstream infection was diagnosed at a median of 19 days (interquartile range, 8-36) after catheter insertion. Significant risk factors for central line-associated thrombosis and central line-associated bloodstream infection were younger age, greater surgical complexity, and total catheter days. CONCLUSIONS: Utilization of central venous catheters in pediatric cardiac ICUs differs according to indication for hospitalization. Although thrombosis and central line-associated bloodstream infection are infrequent complications of central venous catheter use in cardiac ICU patients, these events can have important short- and long-term consequences for patients. Total central venous catheter line days were the only modifiable risk factor identified. Future study must focus on understanding central venous catheter practices in high-risk patient subgroups that reduce the prevalence of thrombosis and central line-associated bloodstream infection.

Extubation Failure Rates After Pediatric Cardiac Surgery Vary Across Hospitals.

OBJECTIVES: Many hospitals aim to extubate children early after cardiac surgery, yet it remains unclear how this practice associates with extubation failure. We evaluated adjusted extubation failure rates and duration of postoperative mechanical ventilation across hospitals and assessed cardiac ICU organizational factors associated with extubation failure. DESIGN: Secondary analysis of the Pediatric Cardiac Critical Care Consortium clinical registry. SETTING: Pediatric Cardiac Critical Care Consortium cardiac ICUs. PATIENTS: Patients with qualifying index surgical procedures from August 2014 to June 2017. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We modeled hospital-level adjusted extubation failure rates using multivariable logistic regression. A previously validated Pediatric Cardiac Critical Care Consortium model was used to calculate adjusted postoperative mechanical ventilation. Observed-to-expected ratios for both metrics were derived for each hospital to assess performance. Hierarchical logistic regression was used to assess the association between cardiac ICU factors and extubation failure. Overall, 16,052 surgical hospitalizations were analyzed. Predictors of extubation failure (p < 0.05 in final case-mix adjustment model) included younger age, underweight, greater surgical complexity, airway anomaly, chromosomal anomaly/syndrome, longer cardiopulmonary bypass time, and other preoperative comorbidities. Three hospitals were better-than-expected outliers for extubation failure (95% CI around observed-to-expected < 1), and three hospitals were worse-than-expected (95% CI around observed-to-expected > 1). Two hospitals were better-than-expected outliers for both extubation failure and postoperative mechanical ventilation, and three were worse-than-expected for both. No hospital was an outlier in opposite directions. Greater nursing hours per patient day and percent nursing staff with critical care certification were associated with lower odds of extubation failure. Cardiac ICU factors such as fewer inexperienced nurses, greater percent critical care trained attendings, cardiac ICU-dedicated respiratory therapists, and fewer patients per cardiac ICU attending were not associated with lower odds of extubation failure. CONCLUSIONS: We saw no evidence that hospitals trade higher extubation failure rates for shorter duration of postoperative mechanical ventilation after pediatric cardiac surgery. Increasing specialized cardiac ICU nursing hours per patient day may achieve better extubation outcomes and mitigate the impact of inexperienced nurses.

A Novel Model Demonstrates Variation in Risk-Adjusted Mortality Across Pediatric Cardiac ICUs After Surgery.

OBJECTIVE: To develop a postoperative mortality case-mix adjustment model to facilitate assessment of cardiac ICU quality of care, and to describe variation in adjusted cardiac ICU mortality across hospitals within the Pediatric Cardiac Critical Care Consortium. DESIGN: Observational analysis. SETTING: Multicenter Pediatric Cardiac Critical Care Consortium clinical registry. PARTICIPANTS: All surgical cardiac ICU admissions between August 2014 and May 2016. The analysis included 8,543 admissions from 23 dedicated cardiac ICUs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We developed a novel case-mix adjustment model to measure postoperative cardiac ICU mortality after congenital heart surgery. Multivariable logistic regression was performed to assess preoperative, intraoperative, and immediate postoperative severity of illness variables as candidate predictors. We used generalized estimating equations to account for clustering of patients within hospital and obtain robust SEs. Bootstrap resampling (1,000 samples) was used to derive bias-corrected 95% CIs around each predictor and validate the model. The final model was used to calculate expected mortality at each hospital. We calculated a standardized mortality ratio (observed-to-expected mortality) for each hospital and derived 95% CIs around the standardized mortality ratio estimate. Hospital standardized mortality ratio was considered a statistically significant outlier if the 95% CI did not include 1. Significant preoperative predictors of mortality in the final model included age, chromosomal abnormality/syndrome, previous cardiac surgeries, preoperative mechanical ventilation, and surgical complexity. Significant early postoperative risk factors included open sternum, mechanical ventilation, maximum vasoactive inotropic score, and extracorporeal membrane oxygenation. The model demonstrated excellent discrimination (C statistic, 0.92) and adequate calibration. Comparison across Pediatric Cardiac Critical Care Consortium hospitals revealed five-fold difference in standardized mortality ratio (0.4-1.9). Two hospitals had significantly better-than-expected and two had significantly worse-than-expected mortality. CONCLUSIONS: For the first time, we have demonstrated that variation in mortality as a quality metric exists across dedicated cardiac ICUs. These findings can guide efforts to reduce mortality after cardiac surgery.

Prevalence and risk factors associated with non-attendance in neurodevelopmental follow-up clinic among infants with CHD.

BACKGROUND: Neurodevelopmental impairment is increasingly recognised as a potentially disabling outcome of CHD and formal evaluation is recommended for high-risk patients. However, data are lacking regarding the proportion of eligible children who actually receive neurodevelopmental evaluation, and barriers to follow-up are unclear. We examined the prevalence and risk factors associated with failure to attend neurodevelopmental follow-up clinic after infant cardiac surgery. METHODS: Survivors of infant (<1 year) cardiac surgery at our institution (4/2011-3/2014) were included. Socio-demographic and clinical characteristics were evaluated in neurodevelopmental clinic attendees and non-attendees in univariate and multivariable analyses. RESULTS: A total of 552 patients were included; median age at surgery was 2.4 months, 15% were premature, and 80% had moderate-severe CHD. Only 17% returned for neurodevelopmental evaluation, with a median age of 12.4 months. In univariate analysis, non-attendees were older at surgery, had lower surgical complexity, fewer non-cardiac anomalies, shorter hospital stay, and lived farther from the surgical center. Non-attendee families had lower income, and fewer were college graduates or had private insurance. In multivariable analysis, lack of private insurance remained independently associated with non-attendance (adjusted odds ratio 1.85, p=0.01), with a trend towards significance for distance from surgical center (adjusted odds ratio 2.86, p=0.054 for ⩾200 miles). CONCLUSIONS: The majority of infants with CHD at high risk for neurodevelopmental dysfunction evaluated in this study are not receiving important neurodevelopmental evaluation. Efforts to remove financial/insurance barriers, increase access to neurodevelopmental clinics, and better delineate other barriers to receipt of neurodevelopmental evaluation are needed.

A randomised trial of early palliative care for maternal stress in infants prenatally diagnosed with single-ventricle heart disease.

Children with single-ventricle disease experience high mortality and complex care. In other life-limiting childhood illnesses, paediatric palliative care may mitigate maternal stress. We hypothesised that early palliative care in the single-ventricle population may have the same benefit for mothers. In this pilot randomised trial of early palliative care, mothers of infants with prenatal single-ventricle diagnoses completed surveys measuring depression, anxiety, coping, and quality of life at a prenatal visit and neonatal discharge. Infants were randomised to receive early palliative care - structured evaluation, psychosocial/spiritual, and communication support before surgery - or standard care. Among 56 eligible mothers, 40 enrolled and completed baseline surveys; 38 neonates were randomised, 18 early palliative care and 20 standard care; and 34 postnatal surveys were completed. Baseline Beck Depression Inventory-II and State-Trait Anxiety Index scores exceeded normal pregnant sample scores (mean 13.76±8.46 versus 7.0±5.0 and 46.34±12.59 versus 29.8±6.35, respectively; p=0.0001); there were no significant differences between study groups. The early palliative care group had a decrease in prenatal to postnatal State-Trait Anxiety Index scores (-7.6 versus 0.3 in standard care, p=0.02), higher postnatal Brief Cope Inventory positive reframing scores (p=0.03), and a positive change in PedsQL Family Impact Module communication and family relationships scores (effect size 0.46 and 0.41, respectively). In conclusion, these data show that mothers of infants with single-ventricle disease experience significant depression and anxiety prenatally. Early palliative care resulted in decreased maternal anxiety, improved maternal positive reframing, and improved communication and family relationships.

Epidemiology and Outcomes of Cardiac Arrest in Pediatric Cardiac ICUs.

OBJECTIVES: In-hospital cardiac arrest occurs in 2.6-6% of children with cardiac disease and is associated with significant morbidity and mortality. Much remains unknown about cardiac arrest in pediatric cardiac ICUs; therefore, we aimed to describe cardiac arrest epidemiology in a contemporary multicenter cardiac ICU cohort. DESIGN: Retrospective analysis within the Pediatric Cardiac Critical Care Consortium clinical registry. SETTING: Cardiac ICUs within 23 North American hospitals. PATIENTS: All cardiac medical and surgical patients admitted from August 2014 to July 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 15,908 cardiac ICU encounters (6,498 medical, 9,410 surgical). 3.1% had cardiac arrest; rate was 4.8 cardiac arrest per 1,000 cardiac ICU days. Medical encounters had 50% higher rate of cardiac arrest compared with surgical encounters. Observed (unadjusted) cardiac ICU cardiac arrest prevalence varied from 1% to 5.5% among the 23 centers; cardiac arrest per 1,000 cardiac ICU days varied from 1.1 to 10.4. Over half cardiac arrest occur within 48 hours of admission. On multivariable analysis, prematurity, neonatal age, any Society of Thoracic Surgeons preoperative risk factor, and Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality category 4, 5 had strongest association with surgical encounter cardiac arrest. In medical encounters, independent cardiac arrest risk factors were acute heart failure, prematurity, lactic acidosis greater than 3 mmol/dL, and invasive ventilation 1 hour after admission. Median cardiopulmonary resuscitation duration was 10 minutes, return of spontaneous circulation occurred in 64.5%, extracorporeal cardiopulmonary resuscitation in 27.2%. Unadjusted survival was 53.2% in encounters with cardiac arrest versus 98.2% without. Medical encounters had lower survival after cardiac arrest (37.7%) versus surgical encounters (62.5%); Norwood patients had less than half the survival after cardiac arrest (35.6%) compared with all others. Unadjusted survival after cardiac arrest varied greatly among 23 centers. CONCLUSIONS: We provide contemporary epidemiologic and outcome data for cardiac arrest occurring in the cardiac ICU from a multicenter clinical registry. As detailed above, we highlight high-risk patient cohorts and periods of time that may serve as targets for research and quality improvement initiatives aimed at cardiac arrest prevention.

Epidemiology of Noninvasive Ventilation in Pediatric Cardiac ICUs.

OBJECTIVE: To describe the epidemiology of noninvasive ventilation therapy for patients admitted to pediatric cardiac ICUs and to assess practice variation across hospitals. DESIGN: Retrospective cohort study using prospectively collected clinical registry data. SETTING: Pediatric Cardiac Critical Care Consortium clinical registry. PATIENTS: Patients admitted to cardiac ICUs at PC4 hospitals. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We analyzed all cardiac ICU encounters that included any respiratory support from October 2013 to December 2015. Noninvasive ventilation therapy included high flow nasal cannula and positive airway pressure support. We compared patient and, when relevant, perioperative characteristics of those receiving noninvasive ventilation to all others. Subgroup analysis was performed on neonates and infants undergoing major cardiovascular surgery. To examine duration of respiratory support, we created a casemix-adjustment model and calculated adjusted mean durations of total respiratory support (mechanical ventilation + noninvasive ventilation), mechanical ventilation, and noninvasive ventilation. We compared adjusted duration of support across hospitals. The cohort included 8,940 encounters from 15 hospitals: 3,950 (44%) received noninvasive ventilation and 72% were neonates and infants. Medical encounters were more likely to include noninvasive ventilation than surgical. In surgical neonates and infants, 2,032 (55%) received postoperative noninvasive ventilation. Neonates, extracardiac anomalies, single ventricle, procedure complexity, preoperative respiratory support, mechanical ventilation duration, and postoperative disease severity were associated with noninvasive ventilation therapy (p < 0.001 for all). Across hospitals, noninvasive ventilation use ranged from 32% to 65%, and adjusted mean noninvasive ventilation duration ranged from 1 to 4 days (3-d observed mean). Duration of total adjusted respiratory support was more strongly correlated with duration of mechanical ventilation compared with noninvasive ventilation (Pearson r = 0.93 vs 0.71, respectively). CONCLUSIONS: Noninvasive ventilation use is common in cardiac ICUs, especially in patients admitted for medical conditions, infants, and those undergoing high complexity surgery. We observed wide variation in noninvasive ventilation use across hospitals, though the primary driver of total respiratory support time seems to be duration of mechanical ventilation.

Long-Term Outcomes of Balloon Valvuloplasty for Isolated Pulmonary Valve Stenosis.

To evaluate the long-term cumulative incidence of ≥ moderate pulmonary regurgitation (PR) and re-intervention following balloon pulmonary valvuloplasty (BPV). While BPV for pulmonary valve stenosis (PS) relieves obstruction acutely, long-term outcomes are not well documented. Between 1982 and 2002, 211 patients had BPV for isolated PS. Follow-up data were available for 103 patients. Cumulative incidence of ≥ moderate PR and re-intervention was evaluated and risk factors for ≥ moderate PR assessed in univariate and multivariable analyses. Median age at BPV was 0.7 years (range 1 day-42.2 years); peak catheter gradient was 65 mmHg (range 31-169 mmHg); 23% had critical PS. Sixty-two patients had a recent echocardiogram with median follow-up 15.1 years (range 10.1-26.3 years); 60% had ≥ moderate PR. Three patients had pulmonary valve replacement following BPV due to symptomatic severe PR. In univariate analysis, critical PS, younger age, smaller BSA, and smaller pulmonary annulus at the time of BPV, as well as greater baseline PS gradient by catheterization, were associated with ≥ moderate PR (all p < 0.05). In multivariable analysis, only BSA < 0.3 m2 was independently associated with ≥ moderate PR (adjusted odds ratio 6.4, 95% confidence interval 1.2-33.6). In the largest study to date of > 10-year outcomes following BPV, 60% of patients with available follow-up data developed ≥ moderate PR. Few patients had pulmonary valve replacement. Patients with lower BSA at the time of BPV were more likely to have greater PR at late follow-up.

Out of many, one: integrating data in the paediatric cardiovascular environment.

Large volumes of data and multiple computing platforms are now universal components of paediatric cardiovascular medicine, but are in a constant state of evolution. Often, multiple sets of related data reside in disconnected "silos", resulting in clinical, administrative, and research activities that may be duplicative, inefficient, and at times inaccurate. Comprehensive and integrated data solutions are needed to facilitate these activities across congenital heart centres. We describe methodology, key considerations, successful use cases, and lessons learnt in developing an integrated data platform across our congenital heart centre.

Clinical epidemiology and centre variation in chylothorax rates after cardiac surgery in children: a report from the Pediatric Cardiac Critical Care Consortium.

Introduction Chylothorax after paediatric cardiac surgery incurs significant morbidity; however, a detailed understanding that does not rely on single-centre or administrative data is lacking. We described the present clinical epidemiology of postoperative chylothorax and evaluated variation in rates among centres with a multicentre cohort of patients treated in cardiac ICU. METHODS: This was a retrospective cohort study using prospectively collected clinical data from the Pediatric Cardiac Critical Care Consortium registry. All postoperative paediatric cardiac surgical patients admitted from October, 2013 to September, 2015 were included. Risk factors for chylothorax and association with outcomes were evaluated using multivariable logistic or linear regression models, as appropriate, accounting for within-centre clustering using generalised estimating equations. RESULTS: A total of 4864 surgical hospitalisations from 15 centres were included. Chylothorax occurred in 3.8% (n=185) of hospitalisations. Case-mix-adjusted chylothorax rates varied from 1.5 to 7.6% and were not associated with centre volume. Independent risk factors for chylothorax included age <1 year, non-Caucasian race, single-ventricle physiology, extracardiac anomalies, longer cardiopulmonary bypass time, and thrombosis associated with an upper-extremity central venous line (all p<0.05). Chylothorax was associated with significantly longer duration of postoperative mechanical ventilation, cardiac ICU and hospital length of stay, and higher in-hospital mortality (all p<0.001). CONCLUSIONS: Chylothorax after cardiac surgery in children is associated with significant morbidity and mortality. A five-fold variation in chylothorax rates was observed across centres. Future investigations should identify centres most adept at preventing and managing chylothorax and disseminate best practices.

Fluid Overload Is Associated With Late Poor Outcomes in Neonates Following Cardiac Surgery.

OBJECTIVES: Acute kidney injury is a severe complication of cardiac surgery associated with increased morbidity and mortality; yet, acute kidney injury classification for neonates remains challenging. We characterized patterns of postoperative fluid overload as a surrogate marker for acute kidney injury and as a risk factor of poor postoperative outcomes in neonates undergoing cardiac surgery. DESIGN: Retrospective cohort study. SETTING: Single, congenital heart center destination program. PATIENTS: Four hundred thirty-five neonates undergoing cardiac surgery with cardiopulmonary bypass from January 2006 through December 2010. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographics, diagnosis, and perioperative clinical variables were collected, including daily weights and serum creatinine levels. A composite poor clinical outcome (death, need for renal replacement therapy or extracorporeal life support within 30 postoperative days) was considered the primary outcome measure. Twenty-one neonates (5%) had a composite poor outcome with 7 (2%) requiring renal replacement therapy, 8 (2%) requiring extracorporeal life support, and 14 (3%) dying between 3 and 30 days post surgery. Neonates with a composite poor outcome had significantly higher maximum fluid overload (> 20%) and were slower to diurese. A receiver-operating characteristic curve determined that fluid overload greater than or equal to 16% and serum creatinine greater than or equal to 0.9 on postoperative day 3 were the optimal cutoffs for significant discrimination on the primary outcome (area under the curve = 0.71 and 0.76, respectively). In multivariable analysis, fluid overload greater than or equal to 16% (adjusted odds ratio = 3.7) and serum creatinine adjusted odds ratio 0.9 (adjusted odds ratio = 6.6) on postoperative day 3 remained an independent risk factor for poor outcome. Fluid overload greater than or equal 16% was also significantly associated with cardiac arrest requiring cardiopulmonary resuscitation, prolonged ICU stay, and chest reexploration. CONCLUSIONS: This study highlights the importance of monitoring fluid balance in the neonatal cardiac surgical population and suggests that daily fluid overload, a readily available, noninvasive marker of renal function, may be a sensitive and specific predictor of adverse outcomes.

Severe Acute Kidney Injury Following Stage 1 Norwood Palliation: Effect on Outcomes and Risk of Severe Acute Kidney Injury at Subsequent Surgical Stages.

OBJECTIVES: To identify associations of severe acute kidney injury early after stage 1 (Norwood) operation with risk of severe acute kidney injury and comorbidities at subsequent palliative stages in patients with hypoplastic left heart syndrome and other single ventricle lesions with left-sided obstruction. DESIGN: Retrospective cohort study. Severe acute kidney injury defined as Kidney Disease Improving Global Outcomes stage 3. SETTING: Single pediatric cardiac center. PATIENTS: Infants less than or equal to 28 days old with single ventricle physiology and left-sided obstruction undergoing stage 1 operation between September 2007 and November 2012 (n = 136). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The occurrence rate of severe acute kidney injury was 21% (28/136) following stage 1, 12% (12/98) following stage 2 palliation (superior cavo-pulmonary anastomosis), and 10% (7/73) following stage 3 palliation (total cavo-pulmonary anastomosis). Severe acute kidney injury early after stage 1 operation was significantly associated with continuous intravenous loop diuretic infusion, need for extracorporeal membrane oxygenation, and in-hospital death (all p < 0.05). Gestational age at birth was associated with severe acute kidney injury at stage 2 (p = 0.04) and stage 3 (p = 0.01). Severe acute kidney injury at stage 1 was an independent risk factor for severe acute kidney injury at stage 2 (adjusted odds ratio, 4.3; 95% CI, 1.1-16.9; p = 0.04). Development of severe acute kidney injury after stage 1 was associated with longer mechanical ventilation time after stage 3 (p = 0.047). CONCLUSIONS: Severe acute kidney injury after stage 1 palliation was an independent risk factor for developing severe acute kidney injury at stage 2, and was associated with prolonged duration of mechanical ventilation following stage 3. Information on the incidence and associated risk factors for postoperative acute kidney injury in hypoplastic left heart syndrome patients from multiple congenital heart centers is a necessary next step to further understand the long-term burden of severe acute kidney injury after staged palliation.

Myocardial Oxidative Stress in Infants Undergoing Cardiac Surgery.

Cardiac surgery for congenital heart disease often necessitates a period of myocardial ischemia during cardiopulmonary bypass and cardioplegic arrest, followed by reperfusion after aortic cross-clamp removal. In experimental models, myocardial ischemia-reperfusion is associated with significant oxidative stress and ventricular dysfunction. A prospective observational study was conducted in infants (<1 year) who underwent elective surgical repair of a ventricular septal defect (VSD) or tetralogy of Fallot (TOF). Blood samples were drawn following anesthetic induction (baseline) and directly from the coronary sinus at 1, 3, 5, and 10 min following aortic cross-clamp removal. Samples were analyzed for oxidant stress using assays for thiobarbituric acid-reactive substances, protein carbonyl, 8-isoprostane, and total antioxidant capacity. For each subject, raw assay data were normalized to individual baseline samples and expressed as fold-change from baseline. Results were compared using a one-sample t test with Bonferroni correction for multiple comparisons. Sixteen patients (ten with TOF and six with VSD) were enrolled in the study, and there were no major postoperative complications observed. For the entire cohort, there was an immediate, rapid increase in myocardial oxidative stress that was sustained for 10 min following aortic cross-clamp removal in all biomarker assays (all P < 0.01), except total antioxidant capacity. Infant cardiac surgery is associated with a rapid, robust, and time-dependent increase in myocardial oxidant stress as measured from the coronary sinus in vivo. Future studies with larger enrollment are necessary to assess any association between myocardial oxidative stress and early postoperative outcomes.

Parental Preferences Regarding Outpatient Management of Children with Congenital Heart Disease.

The objective of this study was to identify patterns of health care usage among children with congenital heart disease (CHD) and determine predictors for contacting cardiologists for routine care. Parents of children with CHD completed surveys, indicating which provider they would contact first for 12 concerns. Predictors for preference for cardiologist evaluation were identified by multivariable logistic regression. Surveys were completed by 307 of 925 (33.2%) parents. Median patient age was 9.4 years [interquartile range (IQR) 5.1-14.4 years] with a median of 1 cardiac surgery (IQR 1-3). Most parents agreed primary care physicians (PCPs) could identify problems related to CHD (70.0%) and when to refer to cardiologists (89.6%). More felt PCPs best understood their values (63.2 vs. 29.6%, P < 0.001) and were more accessible (63.5 vs. 33.6%, P < 0.001) than cardiologists. Parents preferred first evaluation by PCPs for 9 of 12 concerns. Preference for cardiology evaluation was independently associated with the number of cardiac catheterizations [adjusted odds ratio (AOR) for ≥2 catheterizations 2.4, 95% confidence interval (CI) 1.1-4.9], belief the cardiologist better knew the child's medical history (AOR 2.4, 95% CI 1.3-4.6), and provider accessibility (AOR 3.6, 95% CI 1.8-7.4). Parents of CHD patients reported close alignment with PCPs and would contact PCPs first for most routine care. However, some populations continue to contact cardiologists for routine care. Further study is needed to clarify best practices for clinician and parent education.

Risk Factors for Interstage Mortality Following the Norwood Procedure: Impact of Sociodemographic Factors.

Interstage mortality remains significant for patients undergoing staged palliation for hypoplastic left heart syndrome and other related single right ventricle malformations (HLV). The purpose of this study was to identify factors related to demographics, socioeconomic position, and perioperative course associated with post-Norwood hospital discharge, pre-stage 2, interstage mortality (ISM). Medical record review was conducted for patients with HLV, born from 1/2000 to 7/2009 and discharged alive following the Norwood procedure. Sociodemographic and perioperative factors were reviewed. Patients were determined to have ISM if they died between Norwood procedure hospital discharge and stage 2 palliation. Univariable and multivariable logistic regressions were performed to identify risk factors associated with ISM. A total of 273 patients were included in the analysis; ISM occurred in 32 patients (12%). Multivariable analysis demonstrated that independent risk factors for interstage mortality included teen mothers [adjusted odds ratio (AOR) 6.6, 95% confidence interval (CI) 1.9-22.5], single adult caregivers (AOR 4.1, 95% CI 1.2-14.4), postoperative dysrhythmia (AOR 2.7, 95% CI 1.1-6.4), and longer ICU stay (AOR 2.7, 95% CI 1.2-6.1). Anatomic and surgical course variables were not associated with ISM in multivariable analysis. Patients with HLV are at increased risk of ISM if born to a teen mother, if they lived in a home with only one adult caregiver, suffered a postoperative dysrhythmia, or experienced a prolonged ICU stay. These risk factors are identifiable, and thus these infants may be targeted for interventions to reduce ISM.