Cardiac surgery-associated acute kidney injury (CS-AKI) and fluid overload (FO) are common among neonates who undergo cardiopulmonary bypass, and increase mortality risk. Current diagnostic criteria may delay diagnosis. Thus, there is a need to identify urine biomarkers that permit earlier and more accurate diagnosis.

This single-centre ancillary prospective cohort study describes age- and disease-specific ranges of 14 urine biomarkers at perioperative time points and explores associations with CS-AKI and FO. Neonates (≤28 days) undergoing cardiac surgery were included. Preterm neonates or those who had pre-operative acute kidney injury were excluded. Urine biomarkers were measured pre-operatively, at 0 to < 8 hours after surgery, and at 8 to 24 hours after surgery. Exploratory outcomes included CS-AKI, defined by the modified Kidney Disease Improving Global Outcomes criteria, and>10% FO, both measured at 48 hours after surgery.

Overall, α-glutathione S-transferase, β-2 microglobulin, albumin, cystatin C, neutrophil gelatinase-associated lipocalin, osteopontin, uromodulin, clusterin, and vascular endothelial growth factor concentrations peaked in the early post-operative period; over the sampling period, kidney injury molecule-1 increased and trefoil factor-3 decreased. In the early post-operative period, β-2 microglobulin and α-glutathione S-transferase were higher in neonates who developed CS-AKI; and clusterin, cystatin C, neutrophil gelatinase-associated lipocalin, osteopontin, and α-glutathione S-transferase were higher in neonates who developed FO.

In a small, single-centre cohort, age- and disease-specific urine biomarker concentrations are described. These data identify typical trends and will inform future studies.

Interstage monitoring programs for single ventricle disease have been developed to reduce morbidity and mortality. There is increased use of telemedicine and mobile application monitoring. It is unknown if there are disparities in use based on patient socio-demographic factors.

We conducted a retrospective cohort study of patients enrolled in the single ventricle monitoring program and KidsHeart application at a single centre from 4/21/2021 to 12/31/2023. We investigated the association of socio-demographic factors with telemedicine usage, mobile application enrollment and usage. We assessed resource utilisation and weight changes by program era.

There were 94 children in the cohort. Patients with Norwood and ductal stent had higher mean telemedicine visits per month (1.8 visits, p = 0.004), without differences based on socio-demographic factors. There were differences in application enrollment with more Black patients enrolled compared to White patients (p = 0.016). There were less Hispanic patients enrolled than Non-Hispanic patients (p = 0.034). There were no Spaish speaking patient’s enrolled (p = 0.0015). There were no patients with maternal education of less than high school enrolled and all those with maternal education of advanced degree were enrolled (p = 0.0016). There was decreased mobile application use in those from neighbourhoods in the lowest income quartile. There were decreased emergency department visits with mobile application monitoring. Mean weight-for-age z-scores had increased from start to completion of the program in all eras.

Differences were seen in mobile application enrollment and usage based on socio-demographic factors. Further work is needed to ensure that all patients have access to mobile application usage.

New drugs to target different pathways in pulmonary hypertension has resulted in increased combination therapy, but details of this use in infants are not well described. In this large multicenter database study, we describe the pharmacoepidemiology of combination pulmonary vasodilator therapy in critically ill infants.

We identified inborn infants discharged home from a Pediatrix neonatal ICU from 1997 to 2020 exposed to inhaled nitric oxide, sildenafil, epoprostenol, or bosentan for greater than two consecutive days. We compared clinical variables and drug utilisation between infants receiving simultaneous combination and monotherapy. We reported each combination’s frequency, timing, and duration and graphically represented drug use over time.

Of the 7681 infants that met inclusion criteria, 664 (9%) received combination therapy. These infants had a lower median gestational age and birth weight, were more likely to have cardiac and pulmonary anomalies, receive cardiorespiratory support, and had higher in-hospital mortality than those receiving monotherapy. Inhaled nitric oxide and sildenafil were most frequently used, and utilisation of combination and monotherapy for all drugs increased over time. Inhaled nitric oxide and epoprostenol were used in infants with a higher gestational age, earlier postnatal age, and shorter duration than sildenafil and bosentan. Dual therapy with inhaled nitric oxide and sildenafil was the most common combination therapy.

Our study revealed an increased use of combination pulmonary vasodilator therapy, favouring inhaled nitric oxide and sildenafil, yet with considerable practice variation. Further research is needed to determine the optimal combination, sequence, dosing, and disease-specific indications for combination therapy.

Mobile health has been shown to improve quality, access, and efficiency of health care in select populations. We sought to evaluate the benefits of mobile health monitoring using the KidsHeart app in an infant CHD population.

We reviewed data submitted to KidsHeart from parents of infants discharged following intervention for high-risk CHD lesions including subjects status post stage 1 single ventricle palliation, ductal stent or surgical shunt, pulmonary artery band, or right ventricular outflow tract stent. We report on the benefits of a novel mobile health red flag scoring system, mobile health growth/feed tracking, and longitudinal neurodevelopmental outcomes tracking.

A total of 69 CHD subjects (63% male, 41% non-white, median age 28 days [interquartile range 20, 75 days]) were included with median mobile health follow-up of 137 days (56, 190). During the analytic window, subjects submitted 5700 mobile health red flag notifications including 245 violations (mean [standard deviation] 3 ± 3.96 per participant) with 80% (55/69) of subjects submitting at least one violation. Violations precipitated 116 interventions including hospital admission in 34 (29%) with trans-catheter evaluation in 15 (13%) of those. Growth data (n = 2543 daily weights) were submitted by 63/69 (91%) subjects and precipitated 31 feed changes in 23 participants. Sixty-eight percent of subjects with age >2 months submitted at least one complete neurodevelopment questionnaire.

In our initial experience, mobile health monitoring using the KidsHeart app enhanced interstage monitoring permitting earlier intervention, allowed for remote tracking of growth feeding, and provided a means for tracking longitudinal neurodevelopmental outcomes.

Complications from pulmonary hypertension are one of the leading contributors to morbidity and mortality post-cardiopulmonary bypass surgery in children with CHD. Pulmonary vasodilator therapies are commonly used post-operatively, but the optimal target patient population, therapy choice, timing of therapy initiation, and duration of therapy are not well defined.

We used PubMed and EMBASE to identify studies from 2000 to 2020 investigating the use of pulmonary vasodilator therapy post-cardiopulmonary bypass in children aged 0–18 years. To ensure eligibility criteria, studies were systematically reviewed by two independent reviewers.

We identified 26 studies of 42,971 children across four medication classes; 23 were single centre, 14 were prospective, and 11 involved randomisation (four of which employed a placebo-control arm). A disproportionate number of children were from a single retrospective study of 41,872 patients. Definitions varied, but change in pulmonary haemodynamics was the most common primary outcome, used in 14 studies. Six studies had clinical endpoints, with mortality the primary endpoint for two studies. Treatment with inhaled nitric oxide, iloprost, and sildenafil all resulted in improved haemodynamics in specific cohorts of children with post-operative pulmonary hypertension, although improved outcomes were not consistently demonstrated across all treated children. Iloprost may be a cheaper alternative to inhaled nitric oxide with similar haemodynamic response.

Studies were predominantly single-centre, a control arm was rarely used in randomised studies, and haemodynamic endpoints varied significantly. Further research is needed to reduce post-operative morbidity and mortality from pulmonary hypertension in children with CHD.

To determine the optimal antithrombotic agent choice, timing of initiation, dosing and duration of therapy for paediatric patients undergoing cardiac surgery with cardiopulmonary bypass.

We used PubMed and EMBASE to systematically review the existing literature of clinical trials involving antithrombotics following cardiac surgery from 2000 to 2020 in children 0–18 years. Studies were assessed by two reviewers to ensure they met eligibility criteria.

We identified 10 studies in 1929 children across three medications classes: vitamin K antagonists, cyclooxygenase inhibitors and indirect thrombin inhibitors. Four studies were retrospective, five were prospective observational cohorts (one of which used historical controls) and one was a prospective, randomised, placebo-controlled, double-blind trial. All included were single-centre studies. Eight studies used surrogate biomarkers and two used clinical endpoints as the primary endpoint. There was substantive variability in response to antithrombotics in the immediate post-operative period. Studies of warfarin and aspirin showed that laboratory monitoring levels were frequently out of therapeutic range (variably defined), and findings were mixed on the association of these derangements with bleeding or thrombotic events. Heparin was found to be safe at low doses, but breakthrough thromboembolic events were common.

There are few paediatric prospective randomised clinical trials evaluating antithrombotic therapeutics post-cardiac surgery; most studies have been observational and seldom employed clinical endpoints. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal drug, timing of initiation, dosing and duration to improve outcomes by limiting post-operative morbidity and mortality related to bleeding or thrombotic events.

Hypotension is an adverse event that may be related to systemic exposure of milrinone; however, the true exposure–safety relationship is unknown.

Using the Pediatric Trials Network multicentre repository, we identified children ≤17 years treated with milrinone. Hypotension was defined according to age, using the Pediatric Advanced Life Support guidelines. Clinically significant hypotension was defined as hypotension with concomitant lactate >3 mg/dl. A prior population pharmacokinetic model was used to simulate milrinone exposures to evaluate exposure–safety relationships.

We included 399 children with a median (quarter 1, quarter 3) age of 1 year (0,5) who received 428 intravenous doses of milrinone (median infusion rate 0.31 mcg/kg/min [0.29,0.5]). Median maximum plasma milrinone concentration was 110.7 ng/ml (48.4,206.2). Median lowest systolic and diastolic blood pressures were 74 mmHg (60,85) and 35 mmHg (25,42), respectively. At least 1 episode of hypotension occurred in 178 (45%) subjects; clinically significant hypotension occurred in 10 (2%). The maximum simulated milrinone plasma concentrations were higher in subjects with clinically significant hypotension (251 ng/ml [129,329]) versus with hypotension alone (86 ng/ml [44, 173]) versus without hypotension (122 ng/ml [57, 208], p = 0.002); however, this relationship was not retained on multivariable analysis (odds ratio 1.01; 95% confidence interval 0.998, 1.01).

We successfully leveraged a population pharmacokinetic model and electronic health record data to evaluate the relationship between simulated plasma concentration of milrinone and systemic hypotension occurrence, respectively, supporting the broader applicability of our novel, efficient, and cost-effective study design for examining drug exposure–response and –safety relationships.

Paediatric cardiac surgery on cardiopulmonary bypass induces substantial physiologic changes that contribute to post-operative morbidity and mortality. Fluid overload and oedema are prevalent complications, routinely treated with diuretics. The optimal diuretic choice, timing of initiation, dose, and interval remain largely unknown.

To guide clinical practice and future studies, we used PubMed and EMBASE to systematically review the existing literature of clinical trials involving diuretics following cardiac surgery from 2000 to 2020 in children aged 0–18 years. Studies were assessed by two reviewers to ensure that they met eligibility criteria.

We identified nine studies of 430 children across four medication classes. Five studies were retrospective, and four were prospective, two of which included randomisation. All were single centre. There were five primary endpoints – urine output, acute kidney injury, fluid balance, change in serum bicarbonate level, and required dose of diuretic. Included studies showed early post-operative diuretic resistance, suggesting higher initial doses. Two studies of ethacrynic acid showed increased urine output and lower diuretic requirement compared to furosemide. Children receiving peritoneal dialysis were less likely to develop fluid overload than those receiving furosemide. Chlorothiazide, acetazolamide, and tolvaptan demonstrated potential benefit as adjuncts to traditional diuretic regimens.

Early diuretic resistance is seen in children following cardiopulmonary bypass. Ethacrynic acid appears superior to furosemide. Adjunct diuretic therapies may provide additional benefit. Study populations were heterogeneous and endpoints varied. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal diuretic, timing of initiation, dose, and interval to improve post-operative outcomes.

Targeted drug development efforts in patients with CHD are needed to standardise care, improve outcomes, and limit adverse events in the post-operative period. To identify major gaps in knowledge that can be addressed by drug development efforts and provide a rationale for current clinical practice, this review evaluates the evidence behind the most common medication classes used in the post-operative care of children with CHD undergoing cardiac surgery with cardiopulmonary bypass.

We systematically searched PubMed and EMBASE from 2000 to 2019 using a controlled vocabulary and keywords related to diuretics, vasoactives, sedatives, analgesics, pulmonary vasodilators, coagulation system medications, antiarrhythmics, steroids, and other endocrine drugs. We included studies of drugs given post-operatively to children with CHD undergoing repair or palliation with cardiopulmonary bypass.

We identified a total of 127 studies with 51,573 total children across medication classes. Most studies were retrospective cohorts at single centres. There is significant age- and disease-related variability in drug disposition, efficacy, and safety.

In this study, we discovered major gaps in knowledge for each medication class and identified areas for future research. Advances in data collection through electronic health records, novel trial methods, and collaboration can aid drug development efforts in standardising care, improving outcomes, and limiting adverse events in the post-operative period.

Infants with moderate-to-severe CHD frequently undergo cardiopulmonary bypass surgery in childhood. Morbidity and mortality are highest in those who develop post-operative low cardiac output syndrome. Vasoactive and inotropic medications are mainstays of treatment for these children, despite limited evidence supporting their use.

To help inform clinical practice, as well as the conduct of future trials, we performed a systematic review of existing literature on inotropes and vasoactives in children after cardiac surgery using the PubMed and EMBASE databases. We included studies from 2000 to 2020, and the patient population was defined as birth – 18 years of age. Two reviewers independently reviewed studies to determine final eligibility.

The final analysis included 37 papers. Collectively, selected studies reported on 12 different vasoactive and inotropic medications in 2856 children. Overall evidence supporting the use of these drugs in children after cardiopulmonary bypass was limited. The majority of studies were small with 30/37 (81%) enrolling less than 100 patients, 29/37 (78%) were not randomised, and safety and efficacy endpoints differed widely, limiting the ability to combine data for meta-analyses.

Vasoactive and inotropic support remain critical parts of post-operative care for children after cardiopulmonary bypass surgery. There is a paucity of data for the selection and dosing of vasoactives and inotropes for these patients. Despite the knowledge gaps that remain, numerous recent innovations create opportunities to rethink the conduct of clinical trials in this high-risk population.

Preoperative mechanical ventilation is associated with morbidity and mortality following CHD surgery, but prior studies lack a comprehensive analysis of how preoperative respiratory support mode and timing affects outcomes.

We retrospectively collected data on children <18 years of age undergoing cardiac surgery at an academic tertiary care medical centre. Using multivariable regression, we examined the association between modes of preoperative respiratory support (nasal cannula, high-flow nasal cannula/noninvasive ventilation, or invasive mechanical ventilation), escalation of preoperative respiratory support, and invasive mechanical ventilation on the day of surgery for three outcomes: operative mortality, postoperative length of stay, and postoperative complications. We repeated our analysis in a subcohort of neonates.

A total of 701 children underwent 800 surgical procedures, and 40% received preoperative respiratory support. Among neonates, 243 patients underwent 253 surgical procedures, and 79% received preoperative respiratory support. In multivariable analysis, all modes of preoperative respiratory support, escalation in preoperative respiratory support, and invasive mechanical ventilation on the day of surgery were associated with increased odds of prolonged length of stay in children and neonates. Children (odds ratio = 3.69, 95% CI 1.2–11.4) and neonates (odds ratio = 8.97, 95% CI 1.31–61.14) on high-flow nasal cannula/noninvasive ventilation had increased odds of operative mortality compared to those on room air.

Preoperative respiratory support is associated with prolonged length of stay and mortality following CHD surgery. Knowing how preoperative respiratory support affects outcomes may help guide surgical timing, inform prognostic conversations, and improve risk stratification models.

Infants with prenatally diagnosed CHD are at high risk for adverse outcomes owing to multiple physiologic and psychosocial factors. Lack of immediate physical postnatal contact because of rapid initiation of medical therapy impairs maternal–infant bonding. On the basis of expected physiology, maternal–infant bonding may be safe for select cardiac diagnoses.

This is a single-centre study to assess safety of maternal–infant bonding in prenatal CHD.

In total, 157 fetuses with prenatally diagnosed CHD were reviewed. On the basis of cardiac diagnosis, 91 fetuses (58%) were prenatally approved for bonding and successfully bonded, 38 fetuses (24%) were prenatally approved but deemed not suitable for bonding at delivery, and 28 (18%) were not prenatally approved to bond. There were no complications attributable to bonding. Those who successfully bonded were larger in weight (3.26 versus 2.6 kg, p<0.001) and at later gestation (39 versus 38 weeks, p<0.001). Those unsuccessful at bonding were more likely to have been delivered via Caesarean section (74 versus 49%, p=0.011) and have additional non-cardiac diagnoses (53 versus 29%, p=0.014). There was no significant difference regarding the need for cardiac intervention before hospital discharge. Infants who bonded had shorter hospital (7 versus 26 days, p=0.02) and ICU lengths of stay (5 versus 23 days, p=0.002) and higher survival (98 versus 76%, p<0.001).

Fetal echocardiography combined with a structured bonding programme can permit mothers and infants with select types of CHD to successfully bond before ICU admission and intervention.

The relationship between sildenafil dosing, exposure, and systemic hypotension in infants is incompletely understood.

The aim of this study was to characterise the relationship between predicted sildenafil exposure and hypotension in hospitalised infants.

We extracted information on sildenafil dosing and clinical characteristics from electronic health records of 348 neonatal ICUs from 1997 to 2013, and we predicted drug exposure using a population pharmacokinetic model.

We identified 232 infants receiving sildenafil at a median dose of 3.2 mg/kg/day (2.0, 6.0). The median steady-state area under the concentration–time curve over 24 hours (AUC24,SS) and maximum concentration of sildenafil (Cmax,SS,SIL) were 712 ng×hour/ml (401, 1561) and 129 ng/ml (69, 293), respectively. Systemic hypotension occurred in 9% of the cohort. In multivariable analysis, neither dosing nor exposure were associated with systemic hypotension: odds ratio=0.96 (95% confidence interval: 0.81, 1.14) for sildenafil dose; 0.87 (0.59, 1.28) for AUC24,SS; 1.19 (0.78, 1.82) for Cmax,SS,SIL.

We found no association between sildenafil dosing or exposure with systemic hypotension. Continued assessment of sildenafil’s safety profile in infants is warranted.

In very low birth weight infants, persistence of a patent ductus arteriosus results in morbidity and mortality. Therapies to close the ductus are effective, but clinical outcomes may depend on the accuracy of diagnosis and the timing of administration. The objective of the present study was to characterise the association between early echocardiography, therapy for patent ductus arteriosus, and outcomes in very low birth weight infants.

This retrospective cohort study used electronic health record data on inborn infants of gestational age ⩽28 weeks and birth weight <1500 g who were discharged after day of life 7 from 362 neonatal ICU from 1997 to 2013. The primary outcome was death between day of life 7 and discharge. Secondary outcomes included bronchopulmonary dysplasia, necrotising enterocolitis, and grade 3 or 4 intraventricular haemorrhage.

This study included a total of 48,551 infants with a median gestational age of 27 weeks (interquartile range 25, 28) and birth weight 870 g (706, 1050). Early echocardiography – that is, performed during days of life 2 to 6 – was performed in 15,971/48,551 (33%) infants, and patent ductus arteriosus was diagnosed in 31,712/48,551 (65%). The diagnosis was more common in infants who had undergone early echocardiography (14,549/15,971 [91%] versus 17,163/32,580 [53%], p<0.001). In multivariable analysis, early echocardiography was not associated with reduced mortality (odds ratio 0.97, 95% CI 0.89–1.05). Results were similar in the subset of infants who received therapy for patent ductus arteriosus (odds ratio 1.01, 95% CI 0.90–1.15).

Early echocardiography was associated with an increased diagnosis of patent ductus arteriosus, but not with decreased mortality.

Systemic hypertension is increasingly recognised in premature infants. There is limited evidence regarding treatment, and most published treatment recommendations are based solely on expert opinions.

We identified all infants born ⩽32 weeks of gestation and ⩽1500 g birth weight discharged from one of 348 neonatal ICUs managed by the Pediatrix Medical Group between 1997 and 2013. We defined antihypertensive drugs as vasodilators, angiotensin-converting enzyme inhibitors, β receptor blockers, calcium channel blockers, and central α2 receptor agonists. We compared characteristics between infants who were treated with at least one antihypertensive drug during their initial hospitalisation and infants who were not prescribed antihypertensive drugs using Wilcoxon’s ranked sum test or Pearson’s χ2-test.

We identified 2504/119,360 (2.1%) infants who required at least one antihypertensive drug. The median postnatal age of first exposure was 48 days (25th, 75th percentile 15, 86), and the median length of therapy was 6 days (1, 16). Hydralazine was the most commonly prescribed antihypertensive with 1280/2504 (51.1%) treated infants exposed to the drug. More than two antihypertensive drugs were administered in 582/2504 (23.2%) infants, and 199/2097 (9.5%) of the treated infants were discharged home on antihypertensive therapy. Infants who received antihypertensive drugs were of lower gestational age (p<0.001) and birth weight (p<0.001) compared with infants not prescribed antihypertensive drugs.

Our study is the largest to describe current antihypertensive drug exposure in a cohort of exclusively premature infants born ⩽32 weeks of gestation. We found wide variations in practice for treating hypertension in premature infants.

The aim of the study was to evaluate the trends in respiratory syncytial virus-related hospitalisations and associated outcomes in children with haemodynamically significant heart disease in the United States of America.

The Kids’ Inpatient Databases (1997–2012) were used to estimate the incidence of respiratory syncytial virus hospitalisation among children ⩽24 months with or without haemodynamically significant heart disease. Weighted multivariable logistic regression and chi-square tests were used to evaluate the trends over time and factors associated with hospitalisation, comparing eras before and after publication of the 2003 American Academy of Pediatrics palivizumab immunoprophylaxis guidelines. Secondary outcomes included in-hospital mortality, morbidity, length of stay, and cost.

Overall, 549,265 respiratory syncytial virus-related hospitalisations were evaluated, including 2518 (0.5%) in children with haemodynamically significant heart disease. The incidence of respiratory syncytial virus hospitalisation in children with haemodynamically significant heart disease decreased by 36% when comparing pre- and post-palivizumab guideline eras versus an 8% decline in children without haemodynamically significant heart disease (p<0.001). Children with haemodynamically significant heart disease had higher rates of respiratory syncytial virus-associated mortality (4.9 versus 0.1%, p<0.001) and morbidity (31.5 versus 3.5%, p<0.001) and longer hospital length of stay (17.9 versus 3.9 days, p<0.001) compared with children without haemodynamically significant heart disease. The mean cost of respiratory syncytial virus hospitalisation in 2009 was $58,166 (95% CI:$46,017, $70,315).

These data provide stakeholders with a means to evaluate the cost–utility of various immunoprophylaxis strategies.

Aortic arch obstruction can be evaluated by catheter peak-to-peak gradient or by Doppler peak instantaneous pressure gradient. Previous studies have shown moderate correlation in discrete coarctation, but few have assessed correlation in patients with more complex aortic reconstruction.

We carried out retrospective comparison of cardiac catheterisations and pre- and post-catheterisation echocardiograms in 60 patients with native/recurrent coarctation or aortic reconstruction. Aortic arch obstruction was defined as peak-to-peak gradient ⩾25 mmHg in patients with native/recurrent coarctation and ⩾10 mmHg in aortic reconstruction.

Diastolic continuation of flow was not associated with aortic arch obstruction in either group. Doppler peak instantaneous pressure gradient, with and without the expanded Bernoulli equation, weakly correlated with peak-to-peak gradient even in patients with a normal cardiac index (r=0.36, p=0.016, and r=0.49, p=0.001, respectively). Receiver operating characteristic curve analysis identified an area under the curve of 0.61 for patients with all types of obstruction, with a cut-off point of 45 mmHg correctly classifying 64% of patients with arch obstruction (sensitivity 39%, specificity 89%). In patients with aortic arch reconstruction who had a cardiac index ⩾3 L/min/m2, a cut-off point of 23 mmHg correctly classified 69% of patients (71% sensitivity, 50% specificity) with an area under the curve of 0.82.

The non-invasive assessment of aortic obstruction remains challenging. The greatest correlation of Doppler indices was noted in patients with aortic reconstruction and a normal cardiac index.