Outcomes of Neonates Born with Symptomatic Tetralogy of Fallot and Absent Ductus Arteriosus.

OBJECTIVE: To test the hypothesis that neonates with symptomatic tetralogy of Fallot (TOF) and absent ductus arteriosus (ADA) have worse clinical outcomes compared with those with a ductus arteriosus (DA), and that this difference is driven by those born with ADA and with critically deficient pulmonary blood flow (CDPBF). STUDY DESIGN: We performed a retrospective, multicenter cohort study of neonates who underwent intervention for symptomatic TOF comparing death and reintervention between subjects with and without a DA identified on fetal echocardiogram or on echocardiogram performed in the first postnatal day. Exclusion criteria were: inability to define DA status, collaterals supplying pulmonary blood flow, atrioventricular septal defect, and absent pulmonary valve. We defined CDPBF as undergoing a procedure to augment pulmonary blood flow on the date of birth or extracorporeal membrane oxygenation prior to such a procedure. RESULTS: The study cohort included 519 patients, among whom 11% had ADA. Patients with ADA were more likely to have a genetic syndrome and had smaller branch pulmonary artery size. In analyses adjusting for center, interventional treatment strategy, genetic syndrome, and minimum branch pulmonary artery size, ADA was associated with higher mortality risk (adjusted hazard ratio of 2.37 (95% CI:1.07,5.27; p=0.034). Seven patients had CDPBF (1.3% of the entire cohort and 12% of patients with ADA). CONCLUSIONS: A minority of symptomatic TOF neonates have ADA, which is associated with higher adjusted mortality risk compared with those with a DA. CDPBF appears to be a rare but important entity in this population.

Association of patient-level characteristics with long-term outcomes after Fontan palliation: Rationale, design, and baseline characteristics of the Pediatric Cardiac Care Consortium Fontan cohort study.

BACKGROUND: The Fontan operation is used to palliate single ventricle congenital heart defects (CHD) but poses significant morbidity and mortality risks. We present the design, planned analyses, and rationale for a long-term Fontan cohort study aiming to examine the association of patient characteristics at the time of Fontan with post-Fontan morbidity and mortality. METHODS AND RESULTS: We used the Pediatric Cardiac Care Consortium (PCCC), a US-based, multicenter registry of pediatric cardiac surgeries to identify patients who underwent the Fontan procedure for single ventricle CHD between 1 and 21 years of age. The primary outcomes are in-hospital Fontan failure (death or takedown) and post-discharge mortality through 2022. A total of 1461 (males 62.1%) patients met eligibility criteria and were included in the analytical cohort. The median age at Fontan evaluation was 3.1 years (IQR: 2.4-4.3). While 95 patients experienced in-hospital Fontan failure (78 deaths and 17 Fontan takedown), 1366 (93.5%) survived to discharge with Fontan physiology and formed the long-term analysis cohort. Over a median follow-up of 21.2 years (IQR: 18.4-24.5) 184 post-discharge deaths occurred. Thirty-year post Fontan survival was 75.0% (95% CI: 72.3%-77.8%) for all Fontan types with higher rates for current techniques such as lateral tunnel and extracardiac conduit 77.1% (95% CI: 73.5-80.8). CONCLUSION: The PCCC Fontan study aims to identify predictors for post-Fontan morbidity and mortality, enabling risk- stratification and informing surveillance practices. Additionally, the study may guide therapeutic interventions aiming to optimize hemodynamics and enhance Fontan longevity for individual patients.

Short-Term Outcomes, Functional Status, and Risk Factors for Requiring Extracorporeal Life Support After Norwood Operation: A Single-Center Retrospective Study.

Patients requiring extracorporeal life support (ECLS) post-Norwood operation constitute an extremely high-risk group. We retrospectively described short-term outcomes, functional status, and assessed risk factors for requiring ECLS post-Norwood operation between January 2010 and December 2020 in a high-volume center. During the study period, 269 patients underwent a Norwood procedure of which 65 (24%) required ECLS. Of the 65 patients, 27 (41.5%) survived to hospital discharge. Mean functional status scale (FSS) score at discharge increased from 6.0 on admission to 8.48 (p < 0.0001). This change was primary in feeding (p < 0.0001) and respiratory domains (p = 0.017). Seven survivors (26%) developed new morbidity, and two (7%) developed unfavorable functional outcomes. In the regression analysis, we showed that patients with moderate-severe univentricular dysfunction on pre-Norwood transthoracic echocardiogram (odds ratio [OR] = 6.97), modified Blalock Taussig Thomas (m-BTT) shunt as source of pulmonary blood flow (OR = 2.65), moderate-severe atrioventricular valve regurgitation on transesophageal echocardiogram (OR = 8.50), longer cardiopulmonary bypass time (OR = 1.16), longer circulatory arrest time (OR = 1.20), and delayed sternal closure (OR = 3.86), had higher odds of requiring ECLS (p < 0.05). Careful identification of these risk factors is imperative to improve the care of this high-risk cohort and improve overall outcomes.

Captopril to Lisinopril Conversion in Pediatric Cardiothoracic Surgery Patients Less Than 7 Years of Age (RISE-7).

Hypertension after cardiothoracic surgery is common, often requiring pharmacologic management. The recommended first-line antihypertensives in pediatrics are angiotensin converting enzyme inhibitors. Captopril and enalapril are approved for infants and children; however, lisinopril is only approved for > 7 years of age. This study evaluated safety and efficacy of converting from captopril to lisinopril in patients utilizing a pre-defined conversion of 3 mg captopril to 1 mg lisinopril. This was a single center, retrospective study including patients less than 7 years of age admitted for cardiothoracic surgery who received both captopril and lisinopril from 01/01/2017 to 06/01/2022.The primary outcome was mean change in systolic blood pressure (SBP) from baseline for 72 h after conversion of captopril to lisinopril. A total of 99 patients were enrolled. There was a significant decrease in mean SBP (99.12 mmHg vs 94.86 mmHg; p = 0.007) with no difference in DBP (59.23 mmHg vs 61.95 mmHg; p = 0.07) after conversion to lisinopril. Of the 99 patients who were transitioned to lisinopril, 79 (80%) had controlled SBP, 20 (20%) remained hypertensive, 13 (13%) received an increase in their lisinopril dose, and 2 (2%) required an additional antihypertensive agent. There was a low overall rate of AKI (3%) and hyperkalemia (4%) respectively. This study demonstrates that utilizing lisinopril with a conversion rate of 3 mg of captopril to 1 mg of lisinopril was safe and effective for controlling hypertension in pediatric patients following cardiothoracic surgery.

Impact of Antegrade Pulmonary Blood Flow as Patients Progress Through Single-Ventricle Palliations.

BACKGROUND: The impact of antegrade pulmonary blood flow (APBF) during single-ventricle (SV) palliation continues to be debated. We sought to assess its impact on the hemodynamic profile and the short- and long-term outcomes of patients progressing through stages of SV palliation. METHODS: A retrospective single-center study was conducted of SV patients who underwent surgery between January 2010 and December 2020. Patients with APBF were matched to those with no APBF by a propensity score based on body surface area, sex, and type of systemic ventricle. Analysis was performed using appropriate statistics with a significance level of P = .05. RESULTS: Sixty-three patients with APBF were matched with 95 patients with no APBF. At the pre-stage 2 catheterization, APBF patients had a larger left pulmonary artery diameter (z score, 0.1 vs -0.8; P < .042). Patients with APBF had shorter cardiopulmonary bypass time (57.0 vs 79.0 minutes), shorter duration of mechanical ventilation (14.1 vs 17.4 hours), and shorter hospital length of stay (5.0 vs 7.0 days) at stage 2 palliation (P < .05). In the multivariable Cox regression analysis, patients with hypoplastic pulmonary arteries (z scores < -2; adjusted hazard ratio, 9.17) and patients with chromosomal abnormalities/genetic syndrome (adjusted hazard ratio, 4.03) were at increased risk for poor outcomes (P < .05). During the follow-up period, there was no significant difference in risk of the composite poor outcome and long-term survival between groups. CONCLUSIONS: SV patients with APBF had shorter cardiopulmonary bypass time, duration of mechanical ventilation, and hospital length of stay after stage 2 palliation. Patients with hypoplastic pulmonary arteries or chromosomal abnormalities/genetic syndromes had increased risk for poor outcomes. Maintaining APBF has better short-term outcomes, but there are no long-term hemodynamic or survival benefits.

Early Functional Status Change After Cardiopulmonary Resuscitation in a Pediatric Heart Center: A Single-Center Retrospective Study.

Children with cardiac disease are at significantly higher risk for in-hospital cardiac arrest (CA) compared with those admitted without cardiac disease. CA occurs in 2-6% of patients admitted to a pediatric intensive care unit (ICU) and 4-6% of children admitted to the pediatric cardiac-ICU. Treatment of in-hospital CA with cardiopulmonary resuscitation (CPR) results in return of spontaneous circulation in 43-64% of patients and survival rate that varies from 20 to 51%. We aimed to investigate the change in functional status of survivors who experienced an in-hospital CA using the functional status scale (FSS) in our heart center by conducting a retrospective study of all patients 0-18 years who experienced CA between June 2015 and December 2020 in a free-standing university-affiliated quaternary children's hospital. Of the 165 CA patients, 61% (n = 100) survived to hospital discharge. The non-survivors had longer length from admission to CA, higher serum lactate levels peri-CA, and received higher number of epinephrine doses. Using FSS, of the survivors, 26% developed new morbidity, and 9% developed unfavorable outcomes. There was an association of unfavorable outcomes with longer CICU-LOS and number of epinephrine doses given. Sixty-one-percent of CA patients survived to hospital discharge. Of the survivors, 26% developed new morbidity and 91% had favorable outcomes. Future multicenter studies are needed to help better identify modifiable risk factors for development of poor outcomes and help improve outcomes of this fragile patient population.

Bivalirudin or heparin for systemic anticoagulation during pediatric extracorporeal membrane oxygenation: Multicenter retrospective study.

BACKGROUND: The objective of this study is to evaluate the outcomes of unfractionated heparin (UFH) compared to bivalirudin anticoagulation in pediatric ExtraCorporeal Membrane Oxygenation (ECMO). METHODS: A multicenter retrospective study, that included pediatric patients <18 years of age, who were supported on ECMO between June 2017 and May 2020. Patients treated with UFH were matched 2:1 by age and type of ECMO support to the bivalirudin group. RESULTS: The bivalirudin group (75 patients) were matched to 150 patients treated with UFH. Baseline characteristics and comorbidities of the two groups were similar. Veno-Arterial ECMO was the most common mode (141/225 [63 %]) followed by extracorporeal cardiopulmonary resuscitation (48/225 [21 %]). Bivalirudin treatment was associated with lower odds of bleeding events (aOR 0.23, 95%CI 0.12-0.45, p < 0.001) and lower odds of thrombotic events (aOR 0.48, 95%CI 0.23-0.98, p = 0.045). Patients who received bivalirudin had lesser odds for transfusion with fresh frozen plasma, and platelets (aOR 0.26, CI 0.12-0.57, p ≤0.001 and aOR 0.28, CI 0.15-0.53, p < 0.001, respectively). After adjusting for the type of ECMO support and adjusting for age, bivalirudin was associated with a decrease in hospital mortality by 50 % compared to the UFH group (aOR 0.50, 95%CI 0.27-0.93, p = 0.028). Similarly, for neurological disability at time of discharge, bivalirudin was associated with higher odds of intact neurological outcomes compared to UFH (OR 1.99 [95%CI 1.13-3.51], p = 0.017). CONCLUSIONS: This study demonstrated that effective anticoagulation can be achieved with bivalirudin, which was associated with lesser odds of bleeding events and utilization of blood products. Bivalirudin, in comparison with UFH, was associated with greater odds of hospital survival and intact neurological function at the time of discharge. A prospective randomized trial is required to validate the results of this study.

Incidence and recovery of post-surgical heart block in children following cardiac surgery.

BACKGROUND: A subset of patients who develop post-surgical heart block have recovery of atrioventricular node function. Factors predicting recovery are not understood. We investigated our centre's incidence of post-surgical heart block and examine factors associated with recovery of atrioventricular node function. METHODS: We conducted a single-centre retrospective study of patients 0 - 21 years who underwent cardiac surgery between January 2010 and December 2019 and experienced post-operative heart block. Data including patient and clinical characteristics and operative variables were collected and analysed. RESULTS: Of 6333 surgical hospitalisations, 128 (2%) patients developed post-operative heart block. Of the 128 patients, 90 (70%) had return of atrioventricular node function, and 38 (30%) had pacemaker placement. Of the 38 patients who underwent pacemaker placement, 6 (15.8%) had recovery of atrioventricular node function noted on long-term follow-up. Median time from onset of heart block to late atrioventricular node recovery was 13 days (Interquartile range: 5 - 117). Patients with single-ventricle physiology (p = 0.04), greater weight (p = 0.03), and shorter cardiopulmonary bypass time (p = 0.015) were more likely to have recovery. The use of post-operative steroids was similar between all groups (p = 0.445). Infectious or wound complications were similar between pacemaker groups (p = 1). CONCLUSIONS: Two per cent of patients who underwent congenital cardiac surgery developed post-operative heart block, and 0.6% underwent pacemaker placement. Early recovery of atrioventricular node was associated with greater weight at the time of surgery, single-ventricle physiology, and shorter cardiopulmonary bypass time. Late recovery of atrioventricular node conduction following pacemaker placement occurred in 15.8% of patients.

A comparison of high-flow nasal cannula versus non-invasive positive pressure ventilation for respiratory support in infants following cardiac surgery.

BACKGROUND: Following cardiac surgery, infants often remain endotracheally intubated upon arrival to the cardiac ICU. High-flow nasal cannula and non-invasive positive pressure ventilation are used to support patients following extubation. There are limited data on the superiority of either mode to prevent extubation failure. METHODS: We conducted a single-centre retrospective study for infants (<1 year) and/or <10 kg who underwent cardiac surgery between 3/2019-3/2020. Data included patient and clinical characteristics and operative variables. The study aimed to compare high-flow nasal cannula versus non-invasive positive pressure ventilation following extubation and their association with extubation failure. Secondarily, we examined risk factors associated with extubation failure. RESULTS: There were 424 patients who met inclusion criteria, 320 (75%) were extubated to high-flow nasal cannula, 104 (25%) to non-invasive positive pressure ventilation, and 64 patients (15%) failed extubation. The high-flow nasal cannula group had lower rates of extubation failure (11%, versus 29%, p = 0.001). Infants failing extubation were younger and had higher STAT score (p < 0.05). Compared to high-flow nasal cannula, non-invasive positive pressure ventilation patients were at 3.30 times higher odds of failing extubation after adjusting for patient factors (p < 0.0001). CONCLUSIONS: Extubation failure after cardiac surgery occurs in smaller, younger infants, and those with higher risk surgical procedures. Patients extubated to non-invasive positive pressure ventilation had 3.30 higher odds to fail extubation than patients extubated to high-flow nasal cannula. The optimal mode of respiratory support in this patient population is unknown.

Functional Status Change Among Infants, Children, and Adolescents Following Extracorporeal Life Support: a Multicenter Report.

In our retrospective multicenter study of patients 0 to 18 years of age who survived extracorporeal life support (ECLS) between January 2010 and December 2018, we sought to characterize the functional status scale (FSS) of ECLS survivors, determine the change in FSS from admission to discharge, and examine risk factors associated with development of new morbidity and unfavorable outcome. During the study period, there were 1,325 ECLS runs, 746 (56%) survived to hospital discharge. Pediatric patients accounted for 56%. Most common ECLS indication was respiratory failure (47%). ECLS support was nearly evenly split between veno-arterial and veno-venous (51% vs . 49%). Median duration of ECLS in survivors was 5.5 days. Forty percent of survivors had new morbidity, and 16% had an unfavorable outcome. In a logistic regression, African American patients (OR 1.68, p = 0.01), longer duration of ECLS (OR 1.002, p = 0.004), mechanical (OR 1.79, p = 0.002), and renal (OR 1.64, p = 0.015) complications had higher odds of new morbidity. Other races (Pacific Islanders, and Native Americans) (OR 2.89, p = 0.013), longer duration of ECLS (OR 1.002, p = 0.002), and mechanical complications (OR 1.67, p = 0.026) had higher odds of unfavorable outcomes. In conclusion, in our multi-center 9-year ECLS experience, 56% survived, 40% developed new morbidity, and 84% had favorable outcome. Future studies with larger populations could help identify modifiable risk factors that could help guide clinicians in this fragile patient population.

Milrinone for treatment of elevated lactate in the pre-operative newborn with hypoplastic left heart syndrome.

BACKGROUND: There is a paucity of information reported regarding the use of milrinone in patients with hypoplastic left heart syndrome prior to the Norwood procedure. At our institution, milrinone is initiated in the pre-operative setting when over-circulation and elevated serum lactate levels develop. We aimed to review the responses associated with the administration of milrinone in the pre-operative hypoplastic left heart syndrome patient. Second, we compared patients who received high- versus low-dose milrinone prior to Norwood procedure. METHODS: Single-centre retrospective study of patients diagnosed with hypoplastic left heart syndrome between January 2000 and December 2019 who underwent Norwood procedure. Patient characteristics and outcomes were compared. RESULTS: During the study period, 375 patients were identified; 79 (21%) received milrinone prior to the Norwood procedure with median lactate 2.55 mmol/l, and SpO2 93%. Patients who received milrinone were older at the time of Norwood procedure (6 vs. 5 days) and were more likely to be intubated and sedated. In a subset analysis stratifying patients to low- versus high-dose milrinone, median lactate decreased from time of initiation (2.39 vs 2.75 to 1.6 vs 1.8 mmol/l) at 12 hours post-initiation, respectively. Repeated measures analysis showed a significant decrease in lactate levels by 4 hours following initiation of milrinone, that persisted over time, with no significant difference in mean arterial pressure. CONCLUSIONS: The use of milrinone in the pre-operative over-circulated hypoplastic left heart syndrome patient is well tolerated, is associated with decreased lactate levels, and was not associated with significant hypotension or worsening of excess pulmonary blood flow.

Evaluation of Bivalirudin Dosing in Pediatric Extracorporeal Membrane Oxygenation with Renal Insufficiency or Renal Replacement Therapy.

Bivalirudin offers several important advantages of relevance to the management of extracorporeal membrane oxygenation (ECMO) patients. This multicenter retrospective analysis evaluated the bivalirudin dosing in pediatric ECMO and correlated these doses with the severity of renal dysfunction. A total of 75 patients were included in this analyses: estimated glomerular filtration rate (eGFR) > 60 ml/min/1.73 m 2 (n = 29), eGFR 30-60 (n = 18), eGFR < 30 (n = 28), and of those 23 were on renal replacement therapy (RRT). The initial bivalirudin dose used to reach therapeutic anticoagulation in patients with eGFR > 60 was significantly higher than the dose required in those with renal impairment (0.25 mg/kg/hr in patients with eGFR > 60 and 0.19 mg/kg/hr in patients on RRT, 0.18 mg/kg/hr in patients with eGFR 30-60 and 0.13 mg/kg/hr in patients with eGFR < 30 with no RRT). Progressive dose escalations (two to threefold increase) were required to maintain therapeutic range over the initial 4 days of ECMO that coincided with improving renal creatinine clearance during that same time period. Establishing an initial starting dose of bivalirudin contingent upon eGFR is essential for the rapid achievement of target anticoagulation intensity. Further dose adjustments guided by laboratory monitoring is necessary given the dynamic changes in creatinine clearance following ECMO initiation.

Early Functional Status After Surgery for Congenital Heart Disease: A Single-Center Retrospective Study.

OBJECTIVES: The objective of this study is to investigate the change in functional status in infants, children, and adolescents undergoing congenital heart surgery using the Functional Status Scale. DESIGN: A single-center retrospective study. SETTING: A 26-bed cardiac ICU in a free-standing university-affiliated tertiary children's hospital. PATIENTS: All patients 0-18 years who underwent congenital heart surgery from January 1, 2014, to December 31, 2017. INTERVENTIONS: None. MEASUREMENTS AND MIN RESULTS: The primary outcome variable was change in Functional Status Scale scores from admission to discharge. Additionally, two binary outcomes were derived from the primary outcome: new morbidity (change in Functional Status Scale ≥ 3) and unfavorable functional outcome (change in Functional Status Scale ≥ 5); their association with risk factors was assessed using modified Poisson regression. Out of 1,398 eligible surgical encounters, 65 (4.6%) and 15 (1.0%) had evidence of new morbidity and unfavorable functional outcomes, respectively. Higher Surgeons Society of Thoracic and the European Association for Cardio-Thoracic Surgery score, single-ventricle physiology, and longer cardiopulmonary bypass time were associated with new morbidity. Longer hospital length of stay was associated with both new morbidity and unfavorable outcome. CONCLUSIONS: This study demonstrates the novel application of the Functional Status Scale on patients undergoing congenital heart surgery. New morbidity was noted in 4.6%, whereas unfavorable outcome in 1%. There was a small change in the total Functional Status Scale score that was largely attributed to changes in the feeding domain. Higher Society of Thoracic and the European Association for Cardio-Thoracic Surgery score, single-ventricle physiology, and longer cardiopulmonary bypass times were associated with new morbidity, whereas longer hospital length of stay was associated with both new morbidity and unfavorable outcome. Further studies with larger sample size will need to be done to confirm our findings and to better ascertain the utility of Functional Status Scale on this patient population.

Outcomes for unplanned reinterventions following paediatric cardiac surgery for tetralogy of Fallot.

BACKGROUND: Advances in surgical techniques and post-operative management of children with CHD have significantly lowered mortality rates. Unplanned cardiac interventions are a significant complication with implications on morbidity and mortality. METHODS: We conducted a single-centre retrospective case-control study for patients (<18 years) undergoing cardiac surgery for repair of Tetralogy of Fallot between January 2009 and December 2019. Data included patient characteristics, operative variables and outcomes. This study aimed to assess the incidence and risk factors for reintervention of Tetralogy of Fallot after cardiac surgery. The secondary outcome was to examine the incidence of long-term morbidity and mortality in those who underwent unplanned reinterventions. RESULTS: During the study period 29 patients (6.8%) underwent unplanned reintervention, and were matched to 58 patients by age, weight and sex. Median age was 146 days, and median weight was 5.8 kg. Operative mortality was 7%, and 1-year survival was 86% for the entire cohort (cases and controls). Hispanic patients were more likely to have reinterventions (p = 0.04) in the unadjusted analysis, while Asian, Pacific Islander and Native American (p = 0.01) in the multi-variate analysis. Patients that underwent reintervention were more likely to have post-op arrhythmia, genetic syndromes and higher operative and 1-year mortality (p < 0.05). CONCLUSION: Unplanned cardiac interventions following Tetralogy of Fallot repair are common, and associated with increased operative, and 1-year mortality. Race, genetic syndromes and post-operative arrhythmia are associated with increased odds of unplanned reinterventions. Future studies are needed to identify modifiable risk factors to minimise unplanned reinterventions.

Comparison of Invasive and Oscillometric Blood Pressure Measurement in Obese and Nonobese Children.

BACKGROUND: Obesity and hypertension are public health priorities, with obesity considered to be a potential cause of hypertension. Accurate blood pressure (BP) determination is required and often obtained by automated oscillometric cuff devices. We sought to determine the correlation of oscillometric measurement in children, and if obesity was associated with worse correlation between methods than nonobese children. METHODS: Retrospective matched case-controlled study of 100 obese (97-99th percentile) and 100 nonobese (25-70th percentile) children after cardiac surgery with simultaneous systolic, diastolic, and mean invasive and oscillometric measurements. Matching was 1:1 for age, sex, race, and Risk Adjustment for Congenital Heart Surgery-1 score. Intraclass correlation coefficients and Bland-Altman plots were used to determine agreement with 0.75 as threshold. RESULTS: Median age was 13 years (10-15). Agreement was low for systolic (0.65 and 0.61), diastolic (0.68 and 0.61), and mean measurements (0.73 and 0.69) (obese/nonobese). Bland-Altman plots demonstrated oscillometric BP measurements underestimated systolic hypertension (oscillometric readings lower than intra-arterial). Oscillometric measurements underestimated hypotension (systolic oscillometric measurements were higher than intra-arterial). This occurred in obese and nonobese patients. Correlation of oscillometric measurements was similar for nonobese and obese patients. CONCLUSIONS: In this first ever study of simultaneous BP measurement by oscillometric vs. intra-arterial in obese and nonobese children, correlation is below accepted norms. The correlation of oscillometric cuff measurements is not affected by habitus in children. There is less correlation between oscillometric measurements and intra-arterial measurements during hypertension or hypotension. Healthcare providers should be aware of the limitations of oscillometric measurements.

Hyperoxia During Cardiopulmonary Bypass Is Associated With Mortality in Infants Undergoing Cardiac Surgery.

OBJECTIVES: Patients undergoing cardiac surgery using cardiopulmonary bypass have variable degrees of blood oxygen tension during surgery. Hyperoxia has been associated with adverse outcomes in critical illness. Data are not available regarding the association of hyperoxia and outcomes in infants undergoing cardiopulmonary bypass. We hypothesize that among infants undergoing cardiac surgery, hyperoxia during cardiopulmonary bypass is associated with greater odds of morbidity and mortality. DESIGN: Retrospective study. SETTING: Single center at an academic tertiary children's hospital. PATIENTS: All infants (< 1 yr) undergoing cardiopulmonary bypass between January 1, 2015, and December 31, 2017, excluding two patients who were initiated on extracorporeal membrane oxygenation in the operating room. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study included 469 infants with a median age of 97 days (interquartile range, 14-179 d), weight 4.9 kg (interquartile range, 3.4-6.4 kg), and cardiopulmonary bypass time 128 minutes (interquartile range, 91-185 min). A Pao2 of 313 mm Hg (hyperoxia) on cardiopulmonary bypass had highest sensitivity with specificity greater than 50% for association with operative mortality. Approximately, half of the population (237/469) had hyperoxia on cardiopulmonary bypass. Infants with hyperoxia were more likely to have acute kidney injury, prolonged postoperative length of stay, and mortality. They were younger, weighed less, had longer cardiopulmonary bypass times, and had higher Society of Thoracic Surgeons and the European Association for Cardio-Thoracic Surgery mortality scores. There was no difference in sex, race, preoperative creatinine, single ventricle physiology, or presence of genetic syndrome. On multivariable analysis, hyperoxia was associated with greater odds of mortality (odds ratio, 4.3; 95% CI, 1.4-13.2) but failed to identify an association with acute kidney injury or prolonged postoperative length of stay. Hyperoxia was associated with greater odds of mortality in subgroup analysis of neonatal patients. CONCLUSIONS: Hyperoxia occurred in a substantial portion of infants undergoing cardiopulmonary bypass for cardiac surgery. Hyperoxia during cardiopulmonary bypass was an independent risk factor for mortality and may be a modifiable risk factor. Furthermore, hyperoxia during cardiopulmonary bypass was associated with four-fold greater odds of mortality within 30 days of surgery. Hyperoxia failed to identify an association with development of acute kidney injury or prolonged postoperative length of stay when controlling for covariables. Validation of our data among other populations is necessary to better understand and elucidate potential mechanisms underlying the association between excess oxygen delivery during cardiopulmonary bypass and outcome.

Analysis of Inflammatory Cytokines in Postoperative Fontan Pleural Drainage.

Prolonged pleural drainage is a common complication in patients after Fontan palliation and is associated with short- and long- term morbidities. Among many potential etiologies, prolonged drainage has an inflammatory component, but there are no descriptions of cytokines in Fontan pleural drainage to date. This study aimed to examine the inflammatory make-up of Fontan pleural drainage. This prospective age-range-matched cohort study recruited 25 patients undergoing Fontan procedure and 15 bi-ventricular patients undergoing cardiopulmonary bypass (CPB). Chest tube samples were taken on postoperative day (POD) 1-4, 7, and 10. Cytokines were measured using Bio-Plex Assays. Univariate comparisons were made in patient characteristics and cytokine levels. Median age was 3.7 y (IQR 2.8-3.9) for controls and 2.5 y (IQR 2.1-2.9) in Fontan patients (p = 0.02). Median drainage duration and daily volume was higher in Fontan patients (both p < 0.001). Inflammatory cytokines (IL-17A, IFN-y, MIP-1ß, and TNF-α) were higher in Fontan patients than controls (all p < 0.02). There was an increase in pro-inflammatory cytokines (IL-8, MIP-1ß, and TNF-α) from POD1 to the last chest tube day (LCD) in Fontan patients (all p < 0.0001) and a decrease in the anti-inflammatory cytokine IL-10 (p = 0.001). There was no difference in cytokine concentration from POD1 to LCD among controls. There was a significant association with the cytokine concentration of TNF-α on POD1 and duration of chest tube drainage (p < 0.05). Inflammatory cytokine levels in the pleural fluid of Fontan patients are higher compared to bi-ventricular controls and rise over time where controls do not. This suggests ongoing localized inflammation that is not a result of CPB alone and may be an important contributor to pleural drainage in patients after the Fontan procedure.

The Functional Immune Response of Patients on Extracorporeal Life Support.

Extracorporeal life support (ECLS) is a widely used lifesaving technology. Whether ECLS results in immune dysregulation is unclear. This study's aim was to examine whether ECLS affected innate immune response. All patients placed on ECLS were eligible. Blood was obtained before, during, and after ECLS. Function of the innate immune system was measured by ex vivo lipopolysaccharide (LPS)-induced tumor necrosis factor-α (TNF-α) and plasma cytokine levels (interleukin [IL]-6, IL-8, IL-10, and TNF-α). Immunoparalysis was defined as ex vivo TNF-α levels less than 200 pg/ml. Nineteen patients were enrolled with twelve <18 years old. Median ECLS duration was 10 days (range: 3-108); nine patients died. After stratifying the cohort by the presence of immunoparalysis before ECLS, those immunoparalyzed showed increased response to LPS on days 1 and 3 (p = 0.016). Those without pre-ECLS immunoparalysis showed a transient decrease in response on day 3 (p = 0.008). Plasma IL-10 levels were elevated in those with pre-ECLS immunoparalysis and dropped significantly by day 1 (p = 0.031). The number treated with steroids was similar in the two groups. In conclusion, patients with immunoparalysis before ECLS showed a gradual increase in immune function during ECLS, whereas those without immunoparalysis had a transient decrease in responsiveness on day 3.

Functional Status Change Among Children With Extracorporeal Membrane Oxygenation to Support Cardiopulmonary Resuscitation in a Pediatric Cardiac ICU: A Single Institution Report.

OBJECTIVES: The purpose of this study is to describe the functional status of survivors from extracorporeal cardiopulmonary resuscitation instituted during in-hospital cardiac arrest using the Functional Status Scale. We aimed to determine risk factors leading to the development of new morbidity and unfavorable functional outcomes. DESIGN: This was a single-center retrospective chart review abstracting patient characteristics/demographic data, duration of cardiopulmonary resuscitation, duration of extracorporeal membrane oxygenation support, as well as maximum lactate levels within 2 hours before and after extracorporeal cardiopulmonary resuscitation. Cardiac arrest was defined as the administration of chest compressions for a nonperfusing cardiac rhythm. Extracorporeal cardiopulmonary resuscitation was defined by instituting extracorporeal membrane oxygenation during active chest compressions. Functional Status Scale scores were calculated at admission and on hospital discharge for patients who survived. SETTING: Patients admitted in the pediatric cardiac ICU at C.S. Mott Children's Hospital from January 1, 2005, to December 31, 2015. PATIENTS: Children less than 18 years who underwent extracorporeal cardiopulmonary resuscitation. INTERVENTIONS: Not applicable. MEASUREMENTS AND MAIN RESULTS: Of 608 extracorporeal membrane oxygenation events during the study period, 80 were extracorporeal cardiopulmonary resuscitation (14%). There were 40 female patients (50%). Median age was 40 days (interquartile range, 9-342 d). Survival to hospital discharge was 48% (38/80). Median Functional Status Scale score at admission was 6 (interquartile range, 6-6) and at hospital discharge 9 (interquartile range, 8-11). Out of 38 survivors, 19 (50%) had a change of Functional Status Scale score greater than or equal to 3, that is consistent with new morbidity, and 26 (68%) had favorable functional outcomes with a change in Functional Status Scale score of less than 5. CONCLUSIONS: This is the first extracorporeal cardiopulmonary resuscitation report to examine changes in Functional Status Scale from admission (baseline) to discharge as a measure of overall functional outcome. Half of surviving patients (19/38) had new morbidity, while 68% (26/38) had favorable outcomes. Lactate levels, duration of cardiopulmonary resuscitation, and duration of extracorporeal membrane oxygenation were not found to be risk factors for the development of new morbidity and poor functional outcomes. Functional Status Scale may be used as a metric to monitor improvement of extracorporeal cardiopulmonary resuscitation outcomes and help guide research initiatives to decrease morbidity in this patient population.

Surgical Repair of Axillary Artery Aneurysm in a 2-Year-Old Child: A Case Report.

Peripheral aneurysm and pseudoaneurysm of an artery is a well-recognized but rare phenomenon in children. We report a case of an axillary artery aneurysm in a 2-year-old boy with methicillin-resistant Staphylococcus aureus septic shock, acute respiratory distress syndrome, and multiorgan dysfunction syndrome. Definitive surgical treatment with left axillary artery aneurysm exclusion and bypass with greater saphenous vein graft were performed. To our knowledge, this is the only axillary artery aneurysm ever reported in a child.