Neonatal cardiac care, a perspective

Trends of mortality rate in patients with congenital heart defects in Germany-analysis of nationwide data of the Federal Statistical Office of Germany

BACKGROUND

Congenital heart defects (CHD) are still associated with an increased morbidity and mortality. The aim of this study was to analyze trends of mortality rates in patients with CHD between 1998 and 2018 in Germany.

METHODS

Data of registered deaths with an underlying diagnosis of CHD were used to evaluate annual mortality between 1998 and 2018. Polynomial regressions were performed to assess annual changes in CHD-associated mortality rates by age groups.

RESULTS

During the 21-year study period, a total of 11,314 deaths were attributed to CHD with 50.9% of deaths in infants (age < 1 year) and 28.2% in neonates (age ≤ 28 days). The most frequent underlying CHDs associated with death were hypoplastic left heart syndrome (n = 1498, 13.2%), left ventricular outflow tract obstruction (n = 1009, 8.9%), atrial septal defects (n = 771, 6.8%), ventricular septal defects (n = 697, 6.2%), and tetralogy of Fallot (n = 673, 5.9%), and others (n = 6666, 58.9%). Among all patients, annual CHD-related mortality rates declined significantly between 1998 and 2010 (p < 0.0001), followed by a significant annual increase until 2018 (p < 0.0001). However, mortality rates in 2018 in all ages were significantly lower than in 1998.

CONCLUSION

Mortality in CHD patients decreased significantly between 1998 and 2010, but a substantial number of deaths still occurred and even significantly increased in the last 3 years of the observation period particularly in neonates and infants. This renewed slight increase in mortality rate during the last years was influenced mainly by high-risk neonates and infants. Assessment of factors influencing the mortality rate trends in association with CHD in Germany is urgently needed. Obligatory nationwide registration of death cases in relation to surgical and catheter interventions in CHD patients is necessary to provide additional valuable data on the outcome of CHD.

Implementation of Rapid Genome Sequencing for Critically Ill Infants With Complex Congenital Heart Disease

BACKGROUND

Rapid genome sequencing (rGS) has been shown to improve care of critically ill infants. Congenital heart disease (CHD) is a leading cause of infant mortality and is often caused by genetic disorders, yet the utility of rGS has not been prospectively studied in this population.

METHODS

We conducted a prospective evaluation of rGS to improve the care of infants with complex CHD in our cardiac neonatal intensive care unit.

RESULTS

In a cohort of 48 infants with complex CHD, rGS diagnosed 14 genetic disorders in 13 (27%) individuals and led to changes in clinical management in 8 (62%) cases with diagnostic results. These included 2 cases in whom genetic diagnoses helped avert intensive, futile interventions before cardiac neonatal intensive care unit discharge, and 3 cases in whom eye disease was diagnosed and treated in early childhood.

CONCLUSIONS

Our study provides the first prospective evaluation of rGS for infants with complex CHD to our knowledge. We found that rGS diagnosed genetic disorders in 27% of cases and led to changes in management in 62% of cases with diagnostic results. Our model of care depended on coordination between neonatologists, cardiologists, surgeons, geneticists, and genetic counselors. These findings highlight the important role of rGS in CHD and demonstrate the need for expanded study of how to implement this resource to a broader population of infants with CHD.

The choice of perioperative inotropic support impacts the outcome of small infants undergoing complex cardiac surgery: an observational study

BACKGROUND

Vaso-inotropic agents are frequently used to prevent and/or treat low cardiac output syndrome in infants undergoing surgery for congenital heart disease. Due to the lack of comparative studies, their use is largely dependent on physician- and center preferences. The aim was to assess the impact of two different inotropic regimens, milrinone-epinephrine versus dobutamine on postoperative morbi-mortality in young children undergoing complex cardiac surgery.

METHODS

All consecutive children younger than one year of age admitted for complex cardiac surgery (Risk Adjustment in Congenital Heart Surgery-1 [RACHS-1] score ≥3) with cardiopulmonary bypass (CPB) from January 2008 to December 2018 were included. Children received either milrinone in association with low dose epinephrine (milrinone-epinephrine group) or dobutamine (dobutamine group) groups were matched and compared using a propensity score. Our primary outcome was a composite measure including either hospital death and/or the presence of at least two of the following events: respiratory failure, prolonged inotropic support, or renal failure.

RESULTS

Two hundred and fifty patients were included in the analysis. Children in the milrinone-epinephrine group (N.=184) suffered more frequently from a cyanotic heart disease and had longer surgery, CPB, and aortic cross clamp times than those in the dobutamine group (N.=66). After matching, children in the milrinone-epinephrine group had a higher incidence of severe postoperative morbidity or mortality compared to those in the dobutamine group (27.4 versus 13.9%; P=0.016). Respiratory failure (28% vs. 12%), prolonged inotropic support (71% vs. 35%) and in-hospital death (3 vs. 0%) were more frequent in the milrinone-epinephrine group.

CONCLUSIONS

In young infants undergoing complex cardiac surgery, milrinone combined with epinephrine is associated with a higher incidence of postoperative morbidity or mortality compared to dobutamine for perioperative inotropic support. Further prospective randomized studies are required to confirm this finding.

Perioperative Care Models for Neonates With Congenital Heart Disease: Evolving Role of Neonatology Within the Cardiac Intensive Care Unit

A multidisciplinary team is needed to optimally care for infants with congenital heart disease (CHD). Different compositions of teams trained in cardiology, critical care, cardiothoracic surgery, anesthesia, and neonatology have been identified as being primarily responsible for perioperative care of this high-risk population in dedicated cardiac intensive care units (CICUs). Although the specific role of cardiac intensivists has become more well defined over the past two decades, the responsibilities of neonatologists remain highly variable in the CICU with neonatologists providing care along with a unique spectrum of primary, shared, or consultative care. The neonatologist can function as the primary physician and assume all or share responsibility with the cardiac intensivists for the management of infants with CHD. A neonatologist can provide care as a secondary consultant physician in a supportive role for the primary CICU team. Additionally, neonates with CHD can be mixed with older children in a CICU, cohorted in a dedicated space within the CICU or placed in a stand-alone infant CICU without older children. Although variations exist between centers on which model of care is deployed and the location within a CICU, characterization of current practice patterns represents the initial step required to determine optimal best practices to improve the quality of care for neonates with cardiac disease. In this manuscript, we present four models utilized in the United States in which the neonatologist provides neonatal-cardiac-focused care in a dedicated CICU. We also outline the different permutations of location where neonates can be cared for in dedicated pediatric/infant CICUs.

Vasoactive-ventilation-renal score and outcomes in infants and children after cardiac surgery

Introduction

There is a need to index important clinical characteristics in pediatric cardiac surgery that can be obtained early in the postoperative period and accurately predict postoperative outcomes.

Methodology

A prospective cohort study was conducted in the pediatric cardiac ICU and ward on all children aged <18 years undergoing cardiac surgery for congenital heart disease from September 2018 to October 2020. The vasoactive-ventilation-renal (VVR) score was analyzed to predict outcomes of cardiac surgeries with a comparison of postoperative variables.

Results

A total of 199 children underwent cardiac surgery during the study period. The median (interquartile range) age was 2 (0.8-5) years, and the median weight was 9.3 (6-16) kg. The most common diagnoses were ventricular septal defect (46.2%) and tetralogy of Fallot (37.2%). At the 48th h, area under the curve (AUC) (95% CI) values were higher for the VVR score than those for other clinical scores measured. Similarly, at the 48th h, AUC (95% CI) values were higher for the VVR score than those for the other clinical scores measured for the length of stay and mechanical ventilation.

Discussion

The VVR score at 48 h postoperation was found to best correlate with prolonged pediatric intensive care unit (PICU) stay, length of hospitalization, and ventilation duration, with the greatest AUC-receiver operating characteristic (0.715, 0.723, and 0.843, respectively). The 48-h VVR score correlates well with prolonged ICU, hospital stay, and ventilation.

Neurodevelopmental outcomes after neonatal surgery

Children who require surgery in the newborn period are at risk for long-term neurodevelopmental impairment (NDI). There is growing evidence that surgery during this critical window of neurodevelopment gives rise to an increased risk of brain injury, predisposing to neurodevelopmental challenges including motor delays, learning disabilities, executive function impairments, and behavioral disorders. These impairments can have a significant impact on the quality of life of these children and their families. This review explores the current literature surrounding the effect of neonatal surgery on neurodevelopment, as well as the spectrum of proposed mechanisms that may impact neurodevelopmental outcomes. The goal is to identify modifiable risk factors and patients who may benefit from close neurodevelopmental follow-up and early referral to therapy.

Acute Cardiac Care for Neonatal Heart Disease

This manuscript is one component of a larger series of articles produced by the Neonatal Cardiac Care Collaborative that are published in this supplement of Pediatrics. In this review article, we summarize the contemporary physiologic principles, evaluation, and management of acute care issues for neonates with complex congenital heart disease. A multidisciplinary team of authors was created by the Collaborative's Executive Committee. The authors developed a detailed outline of the manuscript, and small teams of authors were assigned to draft specific sections. The authors reviewed the literature, with a focus on original manuscripts published in the last decade, and drafted preliminary content and recommendations. All authors subsequently reviewed and edited the entire manuscript until a consensus was achieved. Topics addressed include cardiopulmonary interactions, the pathophysiology of and strategies to minimize the development of ventilator-induced low cardiac output syndrome, common postoperative physiologies, perioperative bleeding and coagulation, and common postoperative complications.

Impact of Comorbid Prematurity and Congenital Anomalies: A Review

Preterm infants are more likely to be born with congenital anomalies than those who are born at full-term. Conversely, neonates born with congenital anomalies are also more likely to be born preterm than those without congenital anomalies. Moreover, the comorbid impact of prematurity and congenital anomalies is more than cumulative. Multiple common factors increase the risk of brain injury and neurodevelopmental impairment in both preterm babies and those born with congenital anomalies. These include prolonged hospital length of stay, feeding difficulties, nutritional deficits, pain exposure and administration of medications including sedatives and analgesics. Congenital heart disease provides a well-studied example of the impact of comorbid disease with prematurity. Impaired brain growth and maturity is well described in the third trimester in this population; the immature brain is subsequently more vulnerable to further injury. There is a colinear relationship between degree of prematurity and outcome both in terms of mortality and neurological morbidity. Both prematurity and relative brain immaturity independently increase the risk of subsequent neurodevelopmental impairment in infants with CHD. Non-cardiac surgery also poses a greater risk to preterm infants despite the expectation of normal in utero brain growth. Esophageal atresia, diaphragmatic hernia and abdominal wall defects provide examples of congenital anomalies which have been shown to have poorer neurodevelopmental outcomes in the face of prematurity, with associated increased surgical complexity, higher relative cumulative doses of medications, longer hospital and intensive care stay and increased rates of feeding difficulties, compared with infants who experience either prematurity or congenital anomalies alone.

Rethinking Congenital Heart Disease in Preterm Neonates

Congenital heart disease (CHD) and prematurity are the leading causes of infant mortality in the United States. Importantly, the combination of prematurity and CHD results in a further increased risk of mortality and significant morbidity. The key factors in these adverse outcomes are not well understood, but likely include maternal-fetal environment, perinatal and neonatal elements, and challenging postnatal care. Preterm neonates with CHD are born with "double jeopardy": not only do they experience challenges related to immaturity of the lungs, brain, and other organs, but they also must undergo treatment for cardiac disease. The role of the neonatologist caring for preterm infants with CHD has changed with the evolution of the field of pediatric cardiac critical care. Increasingly, neonatologists invested in the cardiovascular care of the newborn with CHD engage at multiple stages in their course, including fetal consultation, delivery room management, preoperative care, and postoperative treatment. A more comprehensive understanding of prematurity and CHD may inform clinical practice and ultimately improve outcomes in preterm infants with CHD. In this review, we discuss the current evidence surrounding neonatal and cardiac outcomes in preterm infants with CHD; examine the prenatal, perinatal, and postnatal factors recognized to influence these outcomes; identify knowledge gaps; consider research and clinical opportunities; and highlight the ways in which a neonatologist can contribute to the care of preterm infants with CHD.

Outcomes after neonatal cardiac surgery: The impact of a dedicated neonatal cardiac program

OBJECTIVES

Prematurity is a risk factor for in-hospital mortality after cardiac surgery. The structure of intensive care unit models designed to deliver optimal care to neonates including those born preterm with critical congenital heart disease is unknown. The objective of this study was to evaluate in-hospital outcomes after cardiac surgery across gestational ages in an institution with a dedicated neonatal cardiac program.

METHODS

This study is a single-center, retrospective review of infants who underwent cardiac surgical interventions from our dedicated neonatal cardiac intensive care program between 2006 and 2017. We evaluated in-hospital mortality and morbidity rates across all gestational ages.

RESULTS

A total of 1238 subjects met inclusion criteria over a 11-year period. Overall in-hospital mortality after cardiac surgery was 6.1%. The mortality rate in very preterm infants (n = 68; <34 weeks' gestation at birth) was 17.6% (odds ratio, 3.52 [1.4-8.53]), versus 4.3% in full-term (n = 563; 39-40 weeks) referent/control infants. Very preterm infants with isolated congenital heart disease (without evidence of other affected organ systems) experienced a mortality rate of 10.5% after cardiac surgery. Neither the late preterm (34-36 ^6/7 weeks) nor the early term (37-38 ^6/7) groups had significantly increased odds of mortality compared with full-term infants. Seventy-eight percent of very preterm infants incurred a preoperative or postoperative complication (odds ratio, 4.78 [2.61-8.97]) compared with 35% of full-term infants.

CONCLUSIONS

In this study of a single center with a dedicated neonatal cardiac program, we report some of the lowest mortality and morbidity rates after cardiac surgery in preterm infants in the recent era. The potential survival advantage of this model is most striking for very preterm infants born with isolated congenital heart disease.

Surgical Interventions During End-of-Life Hospitalizations in Children's Hospitals

OBJECTIVES

To characterize patterns of surgery among pediatric patients during terminal hospitalizations in children's hospitals.

METHODS

We reviewed patients ≤20 years of age who died among 4 424 886 hospitalizations from January 2013-December 2019 within 49 US children's hospitals in the Pediatric Health Information System database. Surgical procedures, identified by International Classification of Diseases procedure codes, were classified by type and purpose. Descriptive statistics characterized procedures, and hypothesis testing determined if undergoing surgery varied by patient age, race and ethnicity, or the presence of chronic complex conditions (CCCs).

RESULTS

Among 33 693 terminal hospitalizations, the majority (n = 30 440, 90.3%) of children were admitted for nontraumatic causes. Of these children, 15 142 (49.7%) underwent surgery during the hospitalization, with the percentage declining over time (P < .001). When surgical procedures were classified according to likely purpose, the most common were to insert or address hardware or catheters (31%), explore or aid in diagnosis (14%), attempt to rescue patient from mortality (13%), or obtain a biopsy (13%). Specific CCC types were associated with undergoing surgery. Surgery during terminal hospitalization was less likely among Hispanic children (47.8%; P < .001), increasingly less likely as patient age increased, and more so for Black, Asian American, and Hispanic patients compared with white patients (P < .001).

CONCLUSIONS

Nearly half of children undergo surgery during their terminal hospitalization, and accordingly, pediatric surgical care is an important aspect of end-of-life care in hospital settings. Differences observed across race and ethnicity categories of patients may reflect different preferences for and access to nonhospital-based palliative, hospice, and end-of-life care.

The effects of Vasoactive-Ventilation-Renal score on pediatric heart surgery

OBJECTIVE:

The effects of Vasoactive-Ventilation-Renal (VVR) score on the evaluation of pediatric heart surgery results were investigated in this study.

METHODS:

This retrospective study included children younger than 18 years of age who were operated for congenital heart disease between was July 1^st- December 31^st 2018. Patients who needed ECMO support at the first postoperative 72 hours were not included in the study group. The postoperative initial, 24^th and 48^th-hour Vasoactive-Inotrope Score (VIS) and VVR scores of all patients were calculated in the intensive care unit (ICU). The effects of these scores on lengthy ICU duration (PCILOS, duration more than the upper 25^th percentile) and to the hospital mortality (before 30 days) were evaluated.

RESULTS:

There were 340 patients in this study. The median age was 12 months (1 day-18 years), and the median weight was 7 kg (2.5 -82 kg). 18% of the patients had single ventricle physiology. Total correction was performed in 88% of the patients. Median RACHS 1 score was 2 (1–6). PCILOS was>112 hours and total mortality was 4%. The 0^th hour VVR ICU c index=0.73 (CI: 0.70–0.77), mortality c index=0.77 (CI: 0.69–0.85). VVR at 24^th hour ICU c index=0.75 (CI: 0.71–0.79), mortality c index=0.86 (CI: 0.81–0.91). VVR at 48^th-hour ICU c index=0.87 (CI: 0.82–0.92), mortality c index=0.92 (CI: 0.87–0.97). The VVR score at 48^th-hour was a strong indicator for the prediction of both LICU duration (odds ratio [OR]: –1.44; p=0.001) and hospital mortality (OR: –1.28; p=0.001).

CONCLUSION:

The postoperative VVR score can be a strong determinant for the prediction of early clinical results in congenital heart disease patients, which were considerably a heterogeneous group.

Gestational Age and Risk of Mortality in Term-Born Critically Ill Neonates Admitted to PICUs in Australia and New Zealand

OBJECTIVES

Gestational age at birth is declining, probably because more deliveries are being induced. Gestational age is an important modifiable risk factor for neonatal mortality and morbidity. We aimed to investigate the association between gestational age and mortality in hospital for term-born neonates (≥ 37 wk') admitted to PICUs in Australia and New Zealand.

DESIGN

Observational multicenter cohort study.

SETTING

PICUs in Australia and New Zealand.

PATIENTS

Term-born neonates (≥ 37 wk) admitted to PICUs.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS:: We studied 5,073 infants born with a gestational age greater than or equal to 37 weeks and were less than 28 days old when admitted to a PICU in Australia or New Zealand between 2007 and 2016. The association between gestational age and mortality was estimated using a multivariable logistic regression model, adjusting for age, sex, indigenous status, Pediatric Index of Mortality version 2, and site. The median gestational age was 39.1 weeks (interquartile range, 38.2-40 wk) and mortality in hospital was 6.6%. Risk of mortality declined log-linearly with gestational age. The adjusted analysis showed a 20% (95% CI, 11-28%) relative reduction in mortality for each extra week of gestation beyond 37 weeks. The effect of gestation was stronger among those who received extracorporeal life support: each extra week of gestation was associated with a 44% (95% CI, 25-57%) relative reduction in mortality. Longer gestation was also associated with reduced length of stay in hospital: each week increase in gestation, the average length of stay decreased by 4% (95% CI, 2-6%).

CONCLUSIONS

Among neonates born at "term" who are admitted to a PICU, increasing gestational age at birth is associated with a substantial reduction in the risk of dying in hospital. The maturational influence on outcome was more strongly noted in the sickest neonates, such as those requiring extracorporeal life support. This information is important in view of the increasing proportion of planned births in both high- and low-/middle-income countries.

Early Peritoneal Dialysis and Major Adverse Events After Pediatric Cardiac Surgery: A Propensity Score Analysis

OBJECTIVES

Early peritoneal dialysis may have a role in modulating the inflammatory response after cardiopulmonary bypass. This study sought to test the effect of early peritoneal dialysis on major adverse events after pediatric cardiac surgery involving cardiopulmonary bypass.

DESIGN

In this observational study, the outcomes in infants post cardiac surgery who received early peritoneal dialysis (within 6 hr of completing cardiopulmonary bypass) were compared with those who received late peritoneal dialysis. The primary outcome was a composite of one or more of cardiac arrest, emergency chest reopening, requirement for extracorporeal membrane oxygenation, or death. Secondary outcomes included duration of mechanical ventilation, length of intensive care, and hospital stay. A propensity score methodology utilizing inverse probability of treatment weighting was used to minimize selection bias due to timing of peritoneal dialysis.

SETTING

Cardiac ICU, The Royal Children's Hospital, Melbourne, VIC, Australia.

PATIENTS

From 2012 to 2015, infants who were commenced on peritoneal dialysis after cardiac surgery were included.

MEASUREMENTS AND MAIN RESULTS

Among 239 eligible infants, 56 (23%) were commenced on early peritoneal dialysis and 183 (77%) on late peritoneal dialysis. At 90 days, early peritoneal dialysis as compared with late peritoneal dialysis was associated with a decreased risk of primary outcome (relative risk, 0.16; 95% CI, 0.05-0.47; p < 0.001 and absolute risk difference, -18.1%; 95% CI, -25.1 to -11.1; p < 0.001). Early peritoneal dialysis was also associated with a decrease in duration of mechanical ventilation and intensive care stay. Among infants with a cardiopulmonary bypass greater than 150 minutes, early peritoneal dialysis was also associated with a survival advantage (relative risk, 0.14; 95% CI, 0.03-0.84; p = 0.03 and absolute risk difference, -7.8; 95% CI, -13.6 to -2; p = 0.008).

CONCLUSIONS

Early peritoneal dialysis in infants post cardiac surgery is associated with a decrease in the rate of major adverse events. The role of early peritoneal dialysis warrants the conduct of randomized trials both in high and low-to-middle income countries; any beneficial effects if confirmed have the potential to strongly influence outcomes for children born with congenital heart disease.

Changing Risk of In-Hospital Cardiac Arrest in Children Following Cardiac Surgery in Victoria, Australia, 2007-2016

BACKGROUND

Reported incidence of in hospital cardiac arrest (IHCA) after paediatric cardiac surgery varies between 3-4% in high income countries and this risk may have changed over time. We sought to examine this trend in detail.

METHODS

A retrospective observational study of 3,781 children who underwent 4,938 cardiac surgeries between 1 January 2007 and 31 December 2016 in a tertiary children's hospital. IHCA was defined as cessation of cardiac mechanical activity requiring cardiac massage for ≥1minute. Surgical complexity was categorised using risk adjusted congenital heart surgery (RACHS-1) category. Poisson regression was used to analyse trends for every two-year period.

RESULTS

There were a total of 211 (4.3%) IHCA events after surgery. These patients were younger, more likely to have had a premature birth, have a chromosomal or genetic syndrome association and have a high surgical complexity. Overall, there was a 52% reduction in IHCA rate over 10 years: reducing from 5.4 /100 surgeries in 2007-08 to 2.6/100 surgeries in 2015-16 (p-trend=<0.001). The reduction was mainly seen in low-to-moderate risk categories (RACHS-1 categories 1-4) and not in high risk categories (RACHS-1 category 5-6). Children in high risk categories were 13.6 times more likely to experience an IHCA (compared to low risk categories). Overall hospital mortality for children suffering IHCA decreased from 42.5/100 patients in 2007-08 to 11.1/100 patients in 2015-16 (p-trend=0.037).

CONCLUSIONS

The IHCA rate following cardiac surgery has more than halved over the last decade; children who experience IHCA also have lower mortality than in previous years. High risk procedures still have a substantial rate of IHCA and efforts are needed to minimise the burden further in this population.

Validation of a definition of excessive postoperative bleeding in infants undergoing cardiac surgery with cardiopulmonary bypass

OBJECTIVE

To derive and validate an objective definition of postoperative bleeding in neonates and infants undergoing cardiac surgery with cardiopulmonary bypass.

METHODS

Using a retrospective cohort of 124 infants and neonates, we included published bleeding definitions and cumulative chest tube output over different postoperative periods (eg, 2, 12, or 24 hours after intensive care unit admission) in a classification and regression tree model to determine chest tube output volumes that were associated with red blood cell transfusions and surgical re-exploration for bleeding in the first 24 hours after intensive care unit admission. After the definition of excessive bleeding was determined, it was validated via a prospective cohort of 77 infants and neonates.

RESULTS

Excessive bleeding was defined as ≥7 mL/kg/h for ≥2 consecutive hours in the first 12 postoperative hours and/or ≥84 mL/kg total for the first 24 postoperative hours and/or surgical re-exploration for bleeding or cardiac tamponade physiology in the first 24 postoperative hours. Excessive bleeding was associated with longer length of hospital stay, increased 30-day readmission rate, and increased transfusions in the postoperative period.

CONCLUSIONS

The proposed standard definition of excessive bleeding is based on readily obtained objective data and relates to important early clinical outcomes. Application and validation by other institutions will help determine the extent to which our specialty should consider this definition for both clinical investigation and quality improvement initiatives.

Late-Term Gestation Is Associated With Improved Survival in Neonates With Congenital Heart Disease Following Postoperative Extracorporeal Life Support

OBJECTIVE

Several population-based studies have shown that gestational age 39-40 weeks at birth is associated with superior outcomes in various pediatric settings. A high proportion of births for neonates with congenital heart disease occur before 39 weeks. We aimed to assess the influence of late-term gestation (39-40 wk) on survival in neonates requiring extracorporeal life support following surgery for congenital heart disease.

DESIGN

Retrospective cohort study.

SETTING

The Royal Children's Hospital, Melbourne, Australia.

PATIENTS

Neonates requiring extracorporeal life support after cardiac surgery for congenital heart disease.

MEASUREMENTS AND MAIN RESULTS

From 2005 to 2014, 110 neonates (10.5% of neonates undergoing cardiac surgery) required extracorporeal life support after cardiac surgery. Indications were failure to separate from cardiopulmonary bypass in 40 (36%), extracorporeal cardiopulmonary resuscitation in 48 (44%), progressive low cardiac output in 15 (14%), and other reasons in seven (6%). Extracorporeal life support duration was 94 hours (interquartile range, 53-135), and 54 (49%) underwent single ventricle repair. Gestation at birth (n [%]) was as follows: less than 37 weeks, 19 (17%); 37-38 weeks, 38 (35%); 39-40 weeks, 50 (45%); 41 weeks or more, 3 (3%). By multivariable analysis (controlling for age, era of extracorporeal life support 2005-2009 vs 2010-2014, single ventricle status and acute renal failure), gestational age of 39-40 weeks was associated with the lowest odds for intensive care mortality: using less than 37 weeks as referent, the adjusted odds ratio (95% CI) for 37-38 weeks was 0.41 (0.12-1.33); for 39-40 weeks, 0.27 (0.08-0.84); and for 41 weeks or more, 1.06 (0.07-14.7). Similar association was also seen in a subcohort of study neonates (n = 66) who were commenced on extracorporeal life support after admission to intensive care: using less than 37 weeks as referent, the adjusted odds ratio (95% CI) for 37-38 weeks was 0.52 (0.10-2.80) and for 39-40 weeks, 0.15 (0.03-0.81).

CONCLUSIONS

In this cohort of neonates requiring extracorporeal life support following cardiac surgery, 39-40 weeks of gestation at birth is associated with the best survival. The additional maturity gained by reaching a gestation of at least 39 weeks is likely to confer a survival advantage in this high-risk cohort.

A Case-Control Analysis of Postoperative Fluid Balance and Mortality After Pediatric Cardiac Surgery

OBJECTIVES

A positive fluid balance after cardiac surgery may be associated with poor outcomes; however, previous studies looking at this association have been limited by the number of deaths in the study population. Our primary aim was to determine the relationship between postoperative cumulative fluid balance and mortality in cardiac surgical patients. Secondary aims were to study the association between fluid balance and duration of mechanical ventilation, intensive care and hospital length of stay.

DESIGN

Case-control study.

SETTING

A 30-bed multidisciplinary PICU.

PATIENTS

All patients admitted to the PICU following cardiac surgery from 2010 to 2014.

INTERVENTIONS

Deaths during PICU admission following cardiac surgery (cases) were matched 1:3 with children who survived to PICU discharge (controls) using the following criteria: age at surgery (within a 20% age range), Risk Adjusted Congenital Heart Surgery (RACHS-1) category, and year of admission.

MEASUREMENTS AND MAIN RESULTS

Of 1,996 eligible children, 46 died (2.3%) of whom 45 (98%) were successfully matched. Cumulative fluid balance on days 2 and 7 was not associated with PICU mortality. On multivariable analysis, factors associated with mortality were cardiopulmonary bypass time (per 10-min increase, odds ratio [95% CI], 1.06 [1.00-1.12]; p = 0.03), extracorporeal membrane oxygenation requirement within 3 days (46.6 [9.47-230.11]; p < 0.001), peak serum chloride (mmol/L) in the first 48 hours (1.12 [1.01-1.23]), and time to start peritoneal dialysis after surgery (in comparison to no peritoneal dialysis, odds ratio [95% CI] in those started on early peritoneal dialysis was 1.07 [0.33-3.41]; p = 0.90 and in late peritoneal dialysis 3.65 [1.21-10.99]; p = 0.02). Children with cumulative fluid balance greater than or equal to 5% by day 2 spent longer on mechanical ventilation (median [interquartile range], 211 hr [97-539] vs 93 hr [34-225]; p <0.001), in PICU (11 d [8-26] vs 6 [3-13]; p < 0.001) and in hospital (22 d [13-39] vs 14 d [8-30]; p = 0.001).

CONCLUSIONS

Early fluid overload is not associated with mortality. However, it is associated with increased duration of mechanical ventilation and PICU length of stay. Early peritoneal dialysis commencement (compared with late peritoneal dialysis) after surgery was associated with decreased mortality.

Structural equation modelling exploration of the key pathophysiological processes involved in cardiac surgery-related acute kidney injury in infants

Background

Uncertainties about the pathophysiological processes resulting in cardiac surgery-related acute kidney injury (AKI) in infants concern the relative impact of the most prominent risk factors, the clinical relevance of changes in glomerular filtration rate vs tubular injury, and the usefulness of available diagnostic tools. Structural equation modelling could allow for the assessment of these complex relationships.

Methods

A structural model was specified using data from a prospective observational cohort of 200 patients <1 year of age undergoing cardiopulmonary bypass surgery. It included four latent variables: AKI, modelled as a construct of perioperative creatinine variation, of oliguria and of urine neutrophil gelatinase-associated lipocalin (uNGAL) concentrations; the cardiopulmonary bypass characteristics; the occurrence of a post-operative low cardiac output syndrome and the post-operative outcome.

Results

The model showed a good fit, and all path coefficients were statistically significant. The bypass was the most prominent risk factor, with a path coefficient of 0.820 (95 % CI 0.527–0.979), translating to a 67.2 % explanation for the risk of AKI. A strong relationships was found between AKI and early uNGAL excretion, and between AKI and the post-operative outcome, with path coefficients of 0.611 (95 % CI 0.347–0.777) and 0.741 (95 % CI 0.610–0.988), respectively. The path coefficient between AKI and a >50 % increase in serum creatinine was smaller, with a path coefficient of 0.443 (95 % CI 0.273–0.596), and was intermediate for oliguria, defined as urine output <0.5 ml kg⁻¹ h⁻¹, with a path coefficient of 0.495 (95 % CI 0.250–0.864). A path coefficient of −0.229 (95 % CI −0.319 to 0.060) suggested that the risk of AKI during the first year of life did not increase with younger age at surgery.

Conclusions

These findings suggest that cardiac surgery-related AKI in infants is a translation of tubular injury, predominately driven by the cardiopulmonary bypass, and linked to early uNGAL excretion and to post-operative outcome.

Trial registration

ClinicalTrials.gov identifier NCT01219998. Registered 11 October 2010.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1350-1) contains supplementary material, which is available to authorized users.

Prospective Validation of a Novel Vasoactive-Ventilation-Renal Score as a Predictor of Outcomes After Pediatric Cardiac Surgery

BACKGROUND

We sought to further validate the novel vasoactive-ventilation-renal (VVR) score in a prospective study of a heterogeneous cohort of children undergoing cardiac surgery that includes patients with single-ventricle anatomy and residual mixing lesions.

METHODS

We prospectively performed an observational study of all children less than 18 years of age who underwent surgery for congenital heart disease at our center from November 2013 to June 2014. We calculated VVR score as follows: vasoactive-inotrope score + ventilation index + (change in serum creatinine from baseline × 10). Admission, peak, and 48-hour measurements were recorded. Outcomes of interest were prolonged duration of mechanical ventilation and intensive care unit and hospital stays, represented by the upper 25% for all patients. Areas under the receiver-operating characteristic curves (AUC) were determined for all study timepoints and outcome variables.

RESULTS

Ninety-two patients were analyzed; their median age was 0.65 (range, 3 days to 17.9 years), and 17 (18%) had single-ventricle anatomy. The VVR measurements outperformed vasoactive-inotrope scores in isolation at all timepoints, with higher AUC values for all outcomes. Of the three timepoints assessed, the 48-hour VVR score most consistently predicted poor outcome, especially with regard to prolonged duration of mechanical ventilation (AUC 0.980) and prolonged intensive care unit stay (AUC 0.919).

CONCLUSIONS

In a heterogeneous population of children undergoing cardiac surgery, the 48-hour VVR score was a very strong predictor of outcomes, and outperformed the more traditional vasoactive-inotrope score. The VVR score, therefore, represents a novel and potentially powerful means of predicting clinical outcomes relatively early in the hospital course of these patients.

Incidental Finding of Cor Triatriatum Sinistrum in an Adult

Cor triatriatum is a congenital heart defect often diagnosed in infancy or childhood. This case study presents an adult with metastatic breast cancer, anemia, and an incidental finding of cor triatriatum sinistrum. On the basis of clinical presentation, the patient was treated conservatively and discharged. Sonographic findings of cor triatriatum sinistrum, along with clinical signs, the significance of other imaging modalities, and potential treatments, are presented.