Initial application in the EACTS and STS Congenital Heart Surgery Databases of an empirically derived methodology of complexity adjustment to evaluate surgical case mix and results

Perioperative Hyper-coagulation and Thrombosis: Cost Analysis After Congenital Heart Surgery

Thrombosis, a major adverse event of congenital heart surgery, has been associated with poor outcomes. We hypothesized that in CHD patients undergoing cardiac surgery, increased perioperative use of pro-coagulant products may be associated with postoperative thrombosis in the setting of hyperfibrinogenemia, leading to greater hospital and blood product costs. Single-center retrospective study. Data from Boston Children's Hospital's electronic health record database was used in this study. All patients undergoing congenital heart surgery between 2015 and 2018 with postoperative fibrinogen levels above 400 mg/dl were reviewed. Of 334 patients with high plasma fibrinogen levels, 28 (8.4%) developed postoperative thrombosis (median age: one year, 59% male). In our cohort, 25 (7%) demonstrated evidence of baseline hypercoagulability by one or more panel test results. Thrombosis was associated with greater hospital and blood product costs, longer ventilation times, and longer hospital and ICU length of stays. Preoperative hypercoagulable state (odds ratio: 2.58, 95% CI [1.07, 9.99], p = 0.002), postoperative red blood cell transfusion (odds ratio: 1.007, 95% CI [1.000, 1.015], p = 0.04), and single ventricle physiology (univariate odds ratio: 2.94, 95% CI [1.09, 7.89], p = 0.03) were predictors of postoperative thrombosis. Preoperative hypercoagulable state and intraoperative platelet transfusion were predictors of hospital cost. Thrombosis was associated with worse in-hospital outcomes and higher costs. Preoperative hypercoagulable state and postoperative red blood cell transfusion were significant predictors of thrombosis. Risk prediction models that can guide thrombosis prevention are needed to improve outcomes of patients undergoing congenital heart surgery.

Prevalence and Risk Factors for Cerebral Palsy in Children With Congenital Heart Disease Based on Risk of Surgical Mortality

BACKGROUND

Children with congenital heart disease (CHD) have a higher prevalence of motor impairment secondary to brain injury, resulting in cerebral palsy (CP). The purpose of this study is to determine the prevalence of CP in CHD in a single-center cohort, stratify risk based on surgical mortality using Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) categories and identify risk factors.

METHODS

Retrospective cohort study of pediatric patients registered in the University of Florida (UF) Society of Thoracic Surgeons Congenital Heart Surgery database from 2006 to 2017 with a diagnosis of CHD who continued follow-up for more than two years at UF.

RESULTS

A total of 701 children with CHD met inclusion criteria. Children identified to have CP were 54 (7.7%). Most common presentation was spastic hemiplegic CP with a Gross Motor Function Classification System of level 2. Analysis of surgical and intensive care factors between the two groups showed that children with CHD and CP had longer time from admission to surgery (P = 0.003), higher STAT categories 4 and 5 (P = 0.038), and higher frequency of brain injury and seizures (P < 0.001). Developmental disabilities and rehabilitation needs were significantly greater for children with CHD and CP when compared with those with CHD alone (P < 0.001).

CONCLUSIONS

In our cohort, 7.7% children with CHD develop CP; this is significantly higher than the 2010 US population estimate of 0.3%. Our study suggests higher STAT categories, brain injury, and seizures are associated with developing CP in children with CHD.

Epidemiology of Postoperative Junctional Ectopic Tachycardia in Infants Undergoing Cardiac Surgery

BACKGROUND

Junctional ectopic tachycardia (JET) complicates congenital heart surgery in 2% to 8.3% of cases. JET is associated with postoperative morbidity in single-center studies. We used the Pediatric Cardiac Critical Care Consortium data registry to provide a multicenter epidemiologic description of treated JET.

METHODS

This is a retrospective study (February 2019-August 2022) of patients with treated JET. Inclusion criteria were (1) <12 months old at the index operation, and (2) treated for JET <72 hours after surgery. Diagnosis was defined by receiving treatment (pacing, cooling, and medications). A multilevel logistic regression analysis with hospital random effect identified JET risk factors. Impact of JET on outcomes was estimated by margins/attributable risk analysis using previous risk-adjustment models.

RESULTS

Among 24,073 patients from 63 centers, 1436 (6.0%) were treated for JET with significant center variability (0% to 17.9%). Median time to onset was 3.4 hours, with 34% present on admission. Median duration was 2 days (interquartile range, 1-4 days). Tetralogy of Fallot, atrioventricular canal, and ventricular septal defect repair represented >50% of JET. Patient characteristics independently associated with JET included neonatal age, Asian race, cardiopulmonary bypass time, open sternum, and early postoperative inotropic agents. JET was associated with increased risk-adjusted durations of mechanical ventilation (incidence rate ratio, 1.6; 95% CI, 1.5-1.7) and intensive care unit length of stay (incidence rate ratio, 1.3; 95% CI, 1.2-1.3), but not mortality.

CONCLUSIONS

JET is treated in 6% of patients with substantial center variability. JET contributes to increased use of postoperative resources. High center variability warrants further study to identify potential modifiable factors that could serve as targets for improvement efforts to ameliorate deleterious outcomes.

Second harvest of Congenital Heart Surgery Database in Türkiye: Current outcomes

Background

This second harvest of the Congenital Heart Surgery Database intended to compare current results with international databases.

Methods

This retrospective study examined a total of 4007 congenital heart surgery procedures from 15 centers in the Congenital Heart Surgery Database between January 2018 and January 2023. International diagnostic and procedural codes were used for data entry. STAT (Society of Thoracic Surgeons and European Association for Cardiothoracic Surgery) mortality scores and categories were used for comparison of the data. Surgical priority status was modified from American Society of Anesthesiologist guidelines. Centers that sent more than 5 cases to the database were included to the study.

Results

Cardiopulmonary bypass and cardioplegic arrest were performed in 2,983 (74.4%) procedures. General risk factors were present in 22.6% of the patients, such as genetic anomaly, syndrome, or prematurity. Overall, 18.9% of the patients had preoperative risk factors (e.g., mechanical ventilation, renal failure, and sepsis). Of the procedures, 610 (15.2%) were performed on neonates, 1,450 (36.2%) on infants, 1,803 (45%) on children, and 144 (3.6%) on adults. The operative timing was elective in 56.5% of the patients, 34.4% were urgent, 8% were emergent, and 1.1% were rescue procedures. Extracorporeal membrane oxygenation support was used in 163 (4%) patients, with a 34.3% survival rate. Overall mortality in this series was 6.7% (n=271). Risk for mortality was higher in patients with general risk factors, such as prematurity, low birth weight neonates, and heterotaxy syndrome. Mortality for patients with preoperative mechanical ventilation was 17.5%. Pulmonary hypertension and preoperative circulatory shock had 11.6% and 10% mortality rates, respectively. Mortality for patients who had no preoperative risk factor was 3.9%. Neonates had the highest mortality rate (20.5%). Intensive care unit and hospital stay time for neonates (median of 17.8 days and 24.8 days, respectively) were also higher than the other age groups. Infants had 6.2% mortality. Hospital mortality was 2.8% for children and 3.5% for adults. Mortality rate was 2.8% for elective cases. Observed mortality rates were higher than expected in the fourth and fifth categories of the STAT system (observed, 14.8% and 51.9%; expected, 9.9% and 23.1%; respectively).

Conclusion

For the first time, outcomes of congenital heart surgery in Türkiye could be compared to the current world experience with this multicenter database study. Increased mortality rate of neonatal and complex heart operations could be delineated as areas that need improvement. The Congenital Heart Surgery Database has great potential for quality improvement of congenital heart surgery in Türkiye. In the long term, participation of more centers in the database may allow more accurate risk adjustment.

Cardiac Arrest With or Without Need for Extracorporeal Life Support After Congenital Cardiac Surgery

BACKGROUND

Postoperative cardiac arrest (CA) with or without need for extracorporeal cardiopulmonary resuscitation (ECPR) is one of the most significant complications in the early postoperative period after pediatric cardiac operation. The objective of this study was to develop and to validate a predictive model of postoperative CA with or without ECPR.

METHODS

In this retrospective cohort study, we reviewed data from patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) between July 20, 2020, and December 31, 2021. Variables included demographic data, presence of preoperative risk factors, The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality categories, perioperative data, residual lesion score (RLS), and vasoactive-inotropic score (VIS). We used multivariable logistic regression analysis to develop a predictive model.

RESULTS

The incidence of CA with or without ECPR was 4.4% (n = 24/544). Patients who experienced postoperative CA with or without ECPR were younger (age, 130 [54-816.5] days vs 626 [127.5-2497.5] days; P < .050) and required longer CPB (253 [154-332.5] minutes vs 130 [87-186] minutes; P < .010) and cross-clamp (116.5 [75.5-143.5] minutes vs 64 [30-111] minutes; P < .020) times; 37.5% of patients with an outcome had at least 1 preoperative risk factor (vs 16.9%; P < .010). Our multivariable logistic regression determined that the presence of at least 1 preoperative risk factor (P = .005), CPB duration (P = .003), intraoperative residual lesion score (P = .009), and postsurgery vasoactive-inotropic score (P = .010) were predictors of the incidence of CA with or without ECPR.

CONCLUSIONS

We developed a predictive model of postoperative CA with or without ECPR after congenital cardiac operation. Our model performed better than the individual scores and risk factors.

Center-Level Variation in Failure to Rescue After Pediatric Cardiac Surgery

BACKGROUND

Although failure to rescue (FTR) is increasingly recognized as a quality metric, studies in congenital cardiac surgery remain sparse. Within a national cohort of children undergoing cardiac operations, we characterized the presence of center-level variation in FTR and hypothesized a strong association with mortality but not complications.

METHODS

All children undergoing congenital cardiac operations were identified in the 2013 to 2019 Nationwide Readmissions Database. FTR was defined as in-hospital death after cardiac arrest, ventricular tachycardia/fibrillation, prolonged mechanical ventilation, pneumonia, stroke, venous thromboembolism, or sepsis, among other complications. Hierarchical models were used to generate hospital-specific, risk-adjusted rates of mortality, complications, and FTR. Centers in the highest decile of FTR were identified and compared with others.

RESULTS

Of an estimated 74,070 patients, 1.9% died before discharge, at least 1 perioperative complication developed in 43.0%, and 4.1% experienced FTR. After multilevel modeling, decreasing age, nonelective admission, and increasing operative complexity were associated with greater odds of FTR. Variations in overall mortality and FTR exhibited a strong, positive relationship (r = 0.97), whereas mortality and complications had a negligible association (r = -0.02). Compared with others, patients at centers with high rates of FTR had similar distributions of age, sex, chronic conditions, and operative complexity.

CONCLUSIONS

In the present study, center-level variations in mortality were more strongly explained by differences in FTR than complications. Our findings suggest the utility of FTR as a quality metric for congenital heart surgery, although further study is needed to develop a widely accepted definition and appropriate risk-adjustment models.

Measuring Critical Care Unit Performance Using a Postoperative Mechanical Ventilation Quality Metric

BACKGROUND

Safely minimizing postoperative mechanical ventilation duration after congenital heart surgery could be a cardiac intensive care unit (CICU) quality measure. We aimed to measure CICU performance using duration of postoperative mechanical ventilation and identify organizational factors associated with this metric.

METHODS

Observational analysis of 16,848 surgical hospitalizations of patients invasively ventilated on admission from the operating room from 26 Pediatric Cardiac Critical Care Consortium CICUs. We fitted a multivariable model to predict duration of postoperative mechanical ventilation adjusting for pre- and postoperative factors to measure CICU performance accounting for postoperative illness severity. We used our model to calculate observed-to-expected (adjusted) ventilation duration ratios for each CICU, describe variation across CICUs, and characterize outliers based on bias-corrected bootstrap 95% CIs. We explored associations between organizational characteristics and patient-level adjusted ventilation duration by adding these as independent variables to the model.

RESULTS

We observed wide variation across CICUs in adjusted ventilation duration ratios, ranging from 0.7 to 1.7. Nine of 26 CICUs had statistically better than expected ventilation duration, while 10 were significantly worse than expected. Organizational characteristics associated with shorter adjusted ventilation duration included mixed (60%-90%) staffing by critical care or anesthesia-trained attendings, lower average attending-to-patient ratio, average CICU daily occupancy 80% to 90%, and greater nurse staffing ratios and experience.

CONCLUSIONS

CICU performance in postoperative duration of mechanical ventilation varies widely across Pediatric Cardiac Critical Care Consortium centers. Several potentially modifiable organizational factors are associated with this metric. Taken together, these findings could spur efforts to improve ventilation duration at outlier hospitals.

Establishing a High-Quality Pediatric Cardiac Surgery Program in Post-Conflict Regions: A Model for Limited Resource Countries

BACKGROUND

Congenital Heart Disease stands as a prominent cause of infant mortality, with notable disparities in surgical outcomes evident between high-income and low- to middle-income countries.

OBJECTIVE

This study presents a collaborative partnership between a local governmental entity and an international private organization to establish a high-quality Pediatric Cardiac Surgery Program in a post-conflict limited resource country, Iraq.

METHODS

A descriptive retrospective study analyzed pediatric cardiac surgery procedures performed by a visiting pediatric heart surgery team from October 2021 to October 2022, funded by the Ministry of Health (MOH). We used the STS-EACTS complexity scoring model (STAT) to assess mortality risks associated with surgical procedures.

RESULTS

A total of 144 patients underwent 148 procedures. Infants comprised 58.3% of the patients. The most common anomalies included tetralogy of Fallot, ventricular septal defect, and various single ventricle categories, constituting 76% of the patient cohort. The overall surgical mortality rate was 4.1%, with an observed/expected surgical mortality rate of 1.1 (95% CI 0.5, 2.3). There was no significant difference between our observed surgical mortality in Category 2, 3, and 4 and those expected/reported by the STS-EACTS Database (p = 0.07, p = 0.72, and p = 0.12, respectively). The expenses incurred by the MOH for conducting surgeries in Iraq were lower than the alternative of sending patients abroad for the same procedures.

CONCLUSION

The partnership model between a local public entity committed to infrastructure development and funding and an international private organization delivering clinical and training services can provide the foundation for building sustainable, high-quality in situ programs in upper-middle-income countries.

Risk factors and early outcomes of repeat sternotomy in 1960 adults with congenital heart disease: A 30-year, single-center study

OBJECTIVE

Patients with congenital heart disease (CHD) increasingly live into adulthood, often requiring cardiac reoperation. We aimed to assess the outcomes of adults with CHD (ACHD) undergoing repeat sternotomy at our institution.

METHODS

Review of our institution's cardiac surgery database identified 1960 ACHD patients undergoing repeat median sternotomy from 1993 to 2023. The primary outcome was early mortality, and the secondary outcome was a composite end point of mortality and significant morbidity. Univariable and multivariable logistic regression models were used to determine factors independently associated with outcomes.

RESULTS

Of the 1960 ACHDs patient undergoing repeat sternotomy, 1183 (60.3%) underwent a second, third (n = 506, 25.8%), fourth (n = 168, 8.5%), fifth (n = 70, 3.5%), and sixth sternotomy or greater (n = 33, 1.6%). CHD diagnoses were minor complexity (n = 145, 7.4%), moderate complexity (n = 1380, 70.4%), and major complexity (n = 435, 22.1%). Distribution of procedures included valve (n = 549, 28%), congenital (n = 625, 32%), aortic (n = 104, 5.3%), and major procedural combinations (n = 682, 34.7%). Overall early mortality was 3.1%. Factors independently associated with early mortality were older age at surgery, CHD of major complexity, preoperative renal failure, preoperative ejection fraction, urgent operation, and postoperative blood transfusion. In addition, sternotomy number and bypass time were independently associated with the composite outcome.

CONCLUSIONS

Despite the increase in early mortality with sternotomy number, sternotomy number was not independently associated with early mortality but with increased morbidity. Improvement strategies should target factors leading to urgent operations, early referral, along with operative efficiency including bypass time and blood conservation.

Racial and Ethnic Variation in ECMO Utilization and Outcomes in Pediatric Cardiac ICU Patients

Background

Previous studies have reported racial disparities in extracorporeal membrane oxygenation (ECMO) utilization in pediatric cardiac patients.

Objectives

The objective of this study was to determine if there was racial/ethnic variation in ECMO utilization and, if so, whether mortality was mediated by differences in ECMO utilization.

Methods

This is a multicenter, retrospective cohort study of the Pediatric Cardiac Critical Care Consortium clinical registry. Analyses were stratified by hospitalization type (medical vs surgical). Logistic regression models were adjusted for confounders and evaluated the association between race/ethnicity with ECMO utilization and mortality. Secondary analyses explored interactions between race/ethnicity, insurance, and socioeconomic status with ECMO utilization and mortality.

Results

A total of 50,552 hospitalizations from 34 hospitals were studied. Across all hospitalizations, 2.9% (N = 1,467) included ECMO. In medical and surgical hospitalizations, Black race and Hispanic ethnicity were associated with severity of illness proxies. In medical hospitalizations, race/ethnicity was not associated with the odds of ECMO utilization. Hospitalizations of other race had higher odds of mortality (adjusted odds ratio [aOR]: 1.61; 95% CI: 1.22-2.12; P = 0.001). For surgical hospitalizations, Black (aOR: 1.24; 95% CI: 1.02-1.50; P = 0.03) and other race (aOR: 1.50; 95% CI: 1.17-1.93; P = 0.001) were associated with higher odds of ECMO utilization. Hospitalizations of Hispanic patients had higher odds of mortality (aOR: 1.31; 95% CI: 1.03-1.68; P = 0.03). No significant interactions were demonstrated between race/ethnicity and socioeconomic status indicators with ECMO utilization or mortality.

Conclusions

Black and other races were associated with increased ECMO utilization during surgical hospitalizations. There were racial/ethnic disparities in outcomes not explained by differences in ECMO utilization. Efforts to mitigate these important disparities should include other aspects of care.

Unplanned Extubation During Pediatric Cardiac Intensive Care: U.S. Multicenter Registry Study of Prevalence and Outcomes

OBJECTIVES

The epidemiology of unplanned extubations (UEs) and associated adverse outcomes in pediatric cardiac ICUs (CICU).

DESIGN

Registry data (August 2014 to October 2020).

SETTING

Forty-five Pediatric Cardiac Critical Care Consortium hospitals.

PATIENTS

Patients receiving mechanical ventilation (MV) via endotracheal tube (ETT).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Fifty-six thousand five hundred eight MV courses occurred in 36,696 patients, with a crude UE rate of 2.8%. In cardiac surgical patients, UE was associated with longer duration of MV, but we failed to find such association in medical patients. In both cohorts, UE was associated with younger age, being underweight, and airway anomaly. In multivariable logistic regression, airway anomaly was associated with UE in all patients. Younger age, higher Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery score category, longer duration of MV, and initial oral rather than nasal ETT are associated with UE in the surgical group, but we failed to find such associations in the medical group. UE was associated with a higher reintubation rate compared with elective extubation (26.8 vs 4.8%; odds ratio [OR], 7.35; 95% CI, 6.44-8.39; p < 0.0001) within 1 day of event. After excluding patients having redirection of care, UE was associated with at least three-fold greater odds for each of ventilator-associated pneumonia (VAP), cardiac arrest, and use of mechanical circulatory support (MCS). However, we failed to identify an association between UE and greater odds of mortality (1.2 vs 0.8%; OR, 1.48; 95% CI, 0.86-2.54; p = 0.15), but uncertainty remains.

CONCLUSIONS

UE in CICU patients is associated with greater odds of cardiac arrest, VAP, and MCS. Cardiac medical and surgical patients in the CICU appear to have different explanatory factors associated with UE, and perhaps these may be modifiable and tested in future collaborative population research.

Using Pharmacokinetic Modeling and Electronic Health Record Data to Predict Clinical and Safety Outcomes after Methylprednisolone Exposure during Cardiopulmonary Bypass in Neonates

Background

Infants undergoing cardiac surgery with cardiopulmonary bypass (CPB) frequently receive intraoperative methylprednisolone (MP) to suppress CPB-related inflammation; however, the optimal dosing strategy and efficacy of MP remain unclear.

Methods

We retrospectively analyzed all infants under 90 days-old who received intra-operative MP for cardiac surgery with CPB from 2014-2017 at our institution. We combined real-world dosing data from the electronic health record (EHR) and two previously developed population pharmacokinetic/pharmacodynamic models to simulate peak concentration (Cmax) and area under the concentration-time curve for 24 h (AUC24) for MP and the inflammatory cytokines interleukin-6 (IL-6) and interleukin-10 (IL-10). We evaluated the relationships between post-operative, safety, and other clinical outcomes obtained from the EHR with each predicted exposure using non-parametric tests.

Results

A total of 142 infants with median post-natal age 8 (interquartile range [IQR]: 5, 37) days received a total dose of 30 (19, 49) mg/kg of MP. Twelve (8%) died, 37 (26%) met the composite post-operative outcome, 114 (80%) met the composite safety outcome, and 23 (16%) had a major complication. Predicted median Cmax and AUC24 IL-6 exposure was significantly higher for infants meeting the composite post-operative outcome and those with major complications. Predicted median Cmax and AUC24 MP exposure was significantly higher for infants requiring insulin. No exposure was associated with death or other safety outcomes.

Conclusions

Pro-inflammatory IL-6, but not MP exposure, was associated with post-operative organ dysfunction, suggesting current MP dosing may not adequately suppress IL-6 or increase IL-10 to impact clinical outcomes. Prospective study will be required to define the optimal exposure-efficacy and exposure-safety profiles in these infants.

A dynamic Norwood mortality estimation: Characterizing individual, updated, predicted mortality trajectories after the Norwood operation

Objective

Post-Norwood mortality remains high and unpredictable. Current models for mortality do not incorporate interstage events. We sought to determine the association of time-related interstage events, along with (pre)operative characteristics, with death post-Norwood and subsequently predict individual mortality.

Methods

From the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort, 360 neonates underwent Norwood operations from 2005 to 2016. Risk of death post-Norwood was modeled using a novel application of parametric hazard analysis, in which baseline and operative characteristics and time-related adverse events, procedures, and repeated weight and arterial oxygen saturation measurements were considered. Individual predicted mortality trajectories that dynamically update (increase or decrease) over time were derived and plotted.

Results

After the Norwood, 282 patients (78%) progressed to stage 2 palliation, 60 patients (17%) died, 5 patients (1%) underwent heart transplantation, and 13 patients (4%) were alive without transitioning to another end point. In total, 3052 postoperative events occurred and 963 measures of weight and oxygen saturation were obtained. Risk factors for death included resuscitated cardiac arrest, moderate or greater atrioventricular valve regurgitation, intracranial hemorrhage/stroke, sepsis, lower longitudinal oxygen saturation, readmission, smaller baseline aortic diameter, smaller baseline mitral valve z-score, and lower longitudinal weight. Each patient's predicted mortality trajectory varied as risk factors occurred over time. Groups with qualitatively similar mortality trajectories were noted.

Conclusions

Risk of death post-Norwood is dynamic and most frequently associated with time-related postoperative events and measures, rather than baseline characteristics. Dynamic predicted mortality trajectories for individuals and their visualization represent a paradigm shift from population-derived insights to precision medicine at the patient level.

Clinical Characteristics and Outcomes in Adults With Moderate-to-Severe Complexity Congenital Heart Disease Undergoing Palliation or Surgical Repair

Background

Congenital heart disease (CHD) survival rate has improved dramatically due to advances in diagnostic and therapeutic techniques. However, concerning the unrepaired CHD population of moderate and severe complexity, the data regarding risk predictors and surgical outcomes are scarce. Our aim was to describe the surgical results and predictors of in-hospital outcomes in adult patients with moderate-to-severe complexity CHD that were not repaired in childhood.

Methods

We conducted a retrospective cohort study that included 49 adult patients with moderate-to-complex CHD who were treated in a single medical centre. Clinical and echocardiographic variables were obtained on admission, after surgical procedures and during follow-up.

Results

Most of the patients were female (66%). Left ventricular ejection fraction and right ventricular outflow tract fractional shortening were within the normal range. The median pulmonary artery systolic pressure was 37 (27-55) mm Hg. The median time was 118 (80-181) minutes for extracorporeal circulation and 76 (49-121) minutes for aortic cross-clamping. The most frequent complication was postoperative complete atrioventricular block (12.2%). In-hospital survival rate was 87.7%. The development of low cardiac output syndrome with predominant right ventricle failure in the postoperative period was the most important predictor of in-hospital death (P = 0.03).

Conclusions

Deciding to treat adults with CHD is challenging in moderate and severe unrepaired cases. Adequate clinical, functional, and imaging evaluation is essential to determine each patient's suitability for surgical management and to achieve the best clinical outcome for this population.

Are Parent Discharge Readiness Scores Effective for the Congenital Heart Disease Patients After Cardiac Surgery?

OBJECTIVE

To assess discharge readiness and clinical engagement post-discharge in familes of children undergoing congenital heart surgery (CHS).

STUDY DESIGN

This prospective cross-sectional study was performed at a major tertiary pediatric cardiac referral center. Eligible parents and caregivers completed a discharge readiness tool, the Readiness for Hospital Discharge Scale for Parents of Hospitalized Children (PedRHDS), via online survey on the day of discharge. Clinical engagement data included subsequent phone calls, clinic visits, emergency department (ED) visits, and hospital readmissions. PedRHDS scores were measured as follows: Very High (9-10), High (8-8.9), Moderate (7-7.9), and Low (<7). Descriptive statistics were used to describe demographic data.

RESULTS

128 families enrolled between April and December 2021. Parent discharge readiness scores ranged from 'High' to 'Very High.' Families with lower socioeconomic status and younger patients (especially single ventricle infants or "interstage") had a higher proportion of clinic visits, ED visits, and hospital readmissions within 30-days post-discharge compared with other groups.

CONCLUSIONS

Discharge readiness scores were not associated with clinical engagement. We identified vulnerable populations as evidenced by a higher frequency of clinical engagement in the immediate post-operative period, particularly younger patients and first time surgeries. While these visits may be appropriate, novel programs could enhance education and emotional support to prevent delay in seeking care or creating excessive stress and anxiety after discharge.

Implications of Transfusion in Adults with Congenital Heart Disease Undergoing Cardiac Surgery

The number of adults with congenital heart disease (CHD) requiring cardiovascular (CV) surgery is increasing rapidly in today's era. We hypothesized that exposure to perioperative blood products is associated with worse outcomes in adults. All adults (≥ 18 years old) undergoing CV surgery with Cardio-Pulmonary Bypass (CPB) between 2015 and 2020 were reviewed retrospectively. Associations between transfusion and outcomes were studied by univariable logistic regression and Wilcoxon rank sum tests. Cox/ logistic regression was used to assess (a) postoperative ventilation time and length of stay, and (b) major complications, respectively. Of 323 patients, 170 (53%) received blood products perioperatively. The median age was 27 (interquartile range [IQR]: 22-36) years, there were 181 (46%) males, and 16 (5%) patients had single ventricle anatomy. Patients receiving products experienced more complications (OR: 6.6, 95% CI: [2.9, 14.7], p < 0.001) specifically, cardiac arrest (OR: 8.8, 95% CI: [1.1, 71.9], p = 0.04). Transfusion was associated with greater frequency of thrombosis ((OR: 7.8, 95% CI: [1.8, 34.7], p = 0.01)), longer ventilation time (HR: 3.0, 95% CI: [2.4, 3.9], p < 0.001), and longer hospital length of stay (HR: 2.7, 95% CI: [2.1, 3.4], p < 0.001). Longer CPB time (OR: 1.0, 95% CI: [1.0, 1.1], p < 0.001) and prior cardiac surgery (OR: 1.6, 95% CI: [1.3, 2.1], p < 0.001) were independent predictors of perioperative blood product transfusion. Adults who received perioperative blood products experienced more complications and worse in-hospital outcomes. Future research on optimizing blood product transfusion based on risk prediction is needed to optimize outcomes in adults with CHD.

Impact of obesity on post-operative arrhythmias after congenital heart surgery in children and young adults

BACKGROUND

Obesity increases the risk of post-operative arrhythmias in adults undergoing cardiac surgery, but little is known regarding the impact of obesity on post-operative arrhythmias after CHD surgery.

METHODS

Patients undergoing CHD surgery from 2007 to 2019 were prospectively enrolled in the parent study. Telemetry was assessed daily, with documentation of all arrhythmias. Patients aged 2-20 years were categorised by body mass index percentile for age and sex (underweight <5, normal 5-85, overweight 85-95, and obese >95). Patients aged >20 years were categorised using absolute body mass index. We investigated the impact of body mass index category on arrhythmias using univariate and multivariate analysis.

RESULTS

There were 1250 operative cases: 12% underweight, 65% normal weight, 12% overweight, and 11% obese. Post-operative arrhythmias were observed in 38%. Body mass index was significantly higher in those with arrhythmias (18.8 versus 17.8, p = 0.003). There was a linear relationship between body mass index category and incidence of arrhythmias: underweight 33%, normal 38%, overweight 42%, and obese 45% (p = 0.017 for trend). In multivariate analysis, body mass index category was independently associated with post-operative arrhythmias (p = 0.021), with odds ratio 1.64 in obese patients as compared to normal-weight patients (p = 0.036). In addition, aortic cross-clamp time (OR 1.007, p = 0.002) and maximal vasoactive-inotropic score in the first 48 hours (OR 1.03, p = 0.04) were associated with post-operative arrhythmias.

CONCLUSION

Body mass index is independently associated with incidence of post-operative arrhythmias in children after CHD surgery.

Clinical implications of acute shunt thrombosis in paediatric patients with systemic-to-pulmonary shunt re-interventions

PURPOSE

Systemic-to-pulmonary shunts are used as a source of pulmonary blood flow in palliated Congenital Heart Disease in neonates and young infants. Shunt thrombosis, often requiring shunt interventions during index hospitalisation, is associated with poor outcomes. We hypothesised that extensive use of perioperative pro-coagulant products may be associated with shunt thrombosis.

METHODS

Children (≤18 years) undergoing systemic-to-pulmonary shunts with in-hospital shunt reinterventions between 2016 and 2020 were reviewed retrospectively. Perioperative associations to shunt thrombosis were examined by univariate logistic regression and Wilcoxon rank sum tests as appropriate. Cox and log transformed linear regression were used to analyse postoperative ventilation duration, length of stay, and cost.

RESULTS

Of 71 patients requiring in-hospital shunt intervention after systemic-to-pulmonary shunts, 10 (14%) had acute shunt thrombosis, and among them five (50%) died. The median age was four (interquartile range: 0-15) months. There were 40 (56%) males, 41 (58%) had single ventricle anatomy, and 29 (40%) were on preoperative anticoagulants. Patients with acute shunt thrombosis received greater volume of platelets (p = 0.04), cryoprecipitate (p = 0.02), and plasma (p = 0.04) postoperatively in the ICU; experienced more complications (p = 0.01) including re-exploration for bleeding (p = 0.008) and death (p = 0.02), had longer hospital length of stays (p = 0.004), greater frequency of other arterial/venous thrombosis (p = 0.02), and greater hospital costs (p = 0.002).

CONCLUSIONS

Patients who develop acute shunt thrombosis receive more blood products perioperatively and experience worse hospital outcomes and higher hospital costs. Future research on prevention/early detection of shunt thrombosis is needed to improve outcomes in infants after systemic-to-pulmonary shunt surgery.

Perioperative junctional ectopic tachycardia associated with congenital heart disease: risk factors and appropriate interventions

The risk factors and the appropriate interventions for perioperative junctional ectopic tachycardia (JET) in congenital heart disease (CHD) surgery have not been sufficiently investigated despite the severity of this complication. This study aimed to examine the risk factors and interventions for perioperative JET. From 2013 to 2020, 1062 surgeries for CHD (median patient age: 4.3 years, range 0.0-53.0) with or without a cardiopulmonary bypass (CPB) were performed at Hokkaido University, Japan. We investigated the correlation between perioperative JET morbidity factors, such as age, genetic background, CPB/aortic cross-clamp (ACC) time, use of inotropes and dexmedetomidine, STAT score, and laboratory indices. The efficacy of JET therapies was also evaluated. Of the 1062 patients, 86 (8.1%) developed JET. The 30-day mortality was significantly high in JET groups (7% vs. 0.8%). The independent risk factors for JET included heterotaxy syndrome [odds ratio (OR) 4.83; 95% confidence interval (CI) 2.18-10.07], ACC time exceeding 90 min (OR 1.90; CI 1.27-2.39), and the use of 3 or more inotropes (OR 4.11; CI 3.02-5.60). The combination of anti-arrhythmic drugs and a temporary pacemaker was the most effective therapy for intractable JET. Perioperative JET after CHD surgery remains a common cause of mortality. Inotrope use was a risk factor for developing JET overall surgery risk. In short ACC surgeries, heterotaxy syndrome could increase the risk of JET, which could develop even without inotrope use in long ACC surgeries. It is crucial not to delay the treatment in cases with unstable hemodynamics caused by this arrhythmia. It is recommended to reduce numbers not dose of inotropes.

Organization of Pediatric Echocardiography Laboratories: Impact of Sonographers on Clinical, Academic, and Financial Performance

Echocardiography has evolved the first-line imaging for diagnosis and management of pediatric and congenital heart disease all over the world. While it recognized as essential component of pediatric cardiac care delivery, organization of pediatric echocardiography services is very heterogeneous across the world, mainly related to significant differences in material and human resources in heterogeneous health care systems. In this paper, we focus on the role of pediatric sonographers, defined as expert technicians in pediatric echocardiography. While in some services sonographers are an essential part of the organizational structure, other laboratories operate only with physicians trained in echocardiography. The impact of sonographers on clinical, academic and financial performance will be discussed. Two organizational models (with and without sonographers) will be compared, and the advantages and disadvantages of each model will be evaluated. Different models of care provision are possible and decisions on organizational models need to be adjusted to the demands and available resources.

Assessment of Current STS Data Elements for Adults with Congenital Heart Disease

BACKGROUND

To identify opportunities for enhanced ACHD data collection, a structured review of existing variables in the STS Congenital Heart Surgery Database (CHSD) and the STS Adult Cardiac Surgery Database (ACSD) was conducted.

METHODS

A working group was assembled representing multiple STS Workforces and Task Forces. The ACSD was reviewed systematically over eight 90 minute calls. ACSD version 4.20.2 and CHSD version 3.41 were used, and the ACSD was approached in sections. ACSD variables were classified as either: 1) represented in identical form in the CHSD (no further discussion), 2) represented in similar form in the CHSD (discussed for potential harmonization of definitions), or 3) not represented in the CHSD (discussed for potential inclusion). Variables felt to be relevant to ACHD were noted, and special consideration was given to STS required fields and variables utilized in existing STS adult risk models. Other factors that were examined were the frequency, utilization, and capture of existing ACSD variables.

RESULTS

Over 22 weeks (8 calls), the existing 1069 variables in version 4.20.2 of the ACSD were discussed. Ultimately, 539 total variables were found to be both 1) relevant to ACHD and 2) not currently collected in the CHSD. These were recommended for inclusion in the next CHSD upgrade for patients older than 18 years.

CONCLUSIONS

For adult patients having case records entered into the CHSD, the inclusion of a limited set of additional data fields from the ACSD should enhance capture of co-morbidities and other clinical data relevant to the ACHD population.

Ethical issues after pre-natal diagnosis

Following pre-natal diagnosis of congenital heart defect parents and family face a dramatic psychological crisis because of their state of shock, contradictory information available on potential outcomes, limited availability of time for decisions and for autonomous choices. Counselling the parents can present additional difficulties due to influence of education, cultural and religious background, individual cognitive and emotional processes, and cross-cultural patient care is a challenging issue for the caregivers. Type and quality of messages transmitted by the caregivers determine the counselling process, with the risk of misunderstandings particularly high with reduced available evidence, or with different outcomes accordingly with the various alternatives of treatment. Since the introduction of pre-natal diagnosis for congenital abnormality, interruption of pregnancy became available on these grounds in many Western countries, and the numbers of babies born with congenital heart defects has declined significantly despite concomitant advances in treatment options and outcomes. Detailed and objective information, with all available options, should be provided after pre-natal diagnosis of congenital heart defect. One of the major achievements of pediatric medicine in the last 50 years is the increased understanding of the pathogenetic causal mechanisms of congenital heart defects as well as its treatment. For congenital heart defects the progress of surgical treatments allowed a huge proportion of these children to reach adult life with a decent quality of life and social integration. Therefore, must be a considerable concern that universal pre-natal diagnosis widespread pregnancy interruption may obviate those gains. A reduction in the post-natal population undergoing treatment may have a significantly deleterious effect on the expertise of the caregivers, producing a reduction in outcome quality. With all respect for the parental choices and the obligations to follow the national laws, is necessary to remark that our society is genuinely ambivalent.

Risk evaluation in adult congenital heart surgery: analysis of the Society of Thoracic Surgeons Congenital Heart Surgery Database risk models on data from the European Congenital Heart Surgeons Association Congenital Database

 

OBJECTIVES

We sought to evaluate the predictive power of the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) mortality score and the adult congenital heart surgery (ACHS) mortality score for the adults undergoing congenital heart operations entered into the European Congenital Heart Surgeons Association (ECHSA) database.

METHODS

The data set comprised 17 662 major operations performed between 1997 and 2019, on patients 18 years of age or older, in European centres participating in the ECHSA database. Each operation was assigned a STAT mortality score and category and an ACHS mortality score. Operative mortality was based on the 30-day status and on the status at hospital discharge. The discriminatory power of the STAT and ACHS scores was assessed using the area under the receiver operating characteristic curve (c-index).

RESULTS

A total of 17 214 (97.46%) operations were assigned ACHS scores. The 3 most frequent primary procedures were closure of the atrial septal defect (19.0%), aortic valve replacement (8.8%) and non-valve-sparing aortic root replacement (6.1%). Operative mortality for ACHS-coded operations was 2.07%. The procedures with the highest mortality were atrial septal defect creation/enlargement (19.0%), lung transplantation (18.8%) and heart transplantation (18.2%). A total of 17 638 (99.86%) operations were assigned a STAT score and category. The operative mortality for STAT-coded operations was 2.27%. The c-index for mortality was 0.720 for the STAT mortality score and 0.701 for the ACHS score.

CONCLUSIONS

The ACHS mortality score and the STAT mortality score reached similar, moderate predictive power in adult patients undergoing congenital heart surgery in ECHSA database.

Pediatric Cardiac Surgical Patterns of Practice and Outcomes in Japan and Europe

OBJECTIVES

The Japan Cardiovascular Surgery Database-Congenital section (JCVSD-Congenital) and the European Congenital Heart Surgeons Association (ECHSA) Congenital Heart Surgery Database (CHSD) share the same nomenclature. We aimed at comparing congenital cardiac surgical patterns of practice and outcomes in Japan and Europe using the JCVSD-Congenital and ECHSA-CHSD.

METHODS AND RESULTS

We examined Japanese (120 units, 63,365 operations) and European (96 units, 90,098 operations) data in JCVSD-Congenital and ECHSA-CHSD from 2011 to 2017. Patients' age and weight, periprocedural times, mortality at hospital discharge, and postoperative length of stay were calculated for ten benchmark operations. There was a significantly higher proportion of ventricular septal defect closures and Glenn operations and a significantly lower proportion of coarctation repairs, tetralogy of Fallot repairs, atrioventricular septal defect repairs, arterial switch operations, truncus repairs, Norwood operations, and Fontan operations in JCVSD-Congenital compared to ECHSA-CHSD. Postoperative length of stay was significantly longer following all benchmark operations in JCVSD-Congenital compared to ECHSA-CHSD. Mean STAT mortality score (Society of Thoracic Surgeons European Association for Cardio-Thoracic Surgery mortality score) was significantly higher in JCVSD-Congenital (0.78) compared to ECHSA-CHSD (0.71). Mortality at hospital discharge was significantly lower in JCVSD-Congenital (4.2%) compared to ECHSA-CHSD (6.0%, P < .001).

CONCLUSIONS

The distribution of the benchmark procedures and age at the time of surgery differ between Japan and Europe. Postoperative length of stay is longer, and the mean complexity is higher in Japan compared to European data. These comparisons of patterns of practice and outcomes demonstrate opportunities for continuing bidirectional transcontinental collaboration and quality improvement.

Adverse Outcomes Prediction for Congenital Heart Surgery: A Machine Learning Approach

OBJECTIVE

Risk assessment tools typically used in congenital heart surgery (CHS) assume that various possible risk factors interact in a linear and additive fashion, an assumption that may not reflect reality. Using artificial intelligence techniques, we sought to develop nonlinear models for predicting outcomes in CHS.

METHODS

We built machine learning (ML) models to predict mortality, postoperative mechanical ventilatory support time (MVST), and hospital length of stay (LOS) for patients who underwent CHS, based on data of more than 235,000 patients and 295,000 operations provided by the European Congenital Heart Surgeons Association Congenital Database. We used optimal classification trees (OCTs) methodology for its interpretability and accuracy, and compared to logistic regression and state-of-the-art ML methods (Random Forests, Gradient Boosting), reporting their area under the curve (AUC or c-statistic) for both training and testing data sets.

RESULTS

Optimal classification trees achieve outstanding performance across all three models (mortality AUC = 0.86, prolonged MVST AUC = 0.85, prolonged LOS AUC = 0.82), while being intuitively interpretable. The most significant predictors of mortality are procedure, age, and weight, followed by days since previous admission and any general preoperative patient risk factors.

CONCLUSIONS

The nonlinear ML-based models of OCTs are intuitively interpretable and provide superior predictive power. The associated risk calculator allows easy, accurate, and understandable estimation of individual patient risks, in the theoretical framework of the average performance of all centers represented in the database. This methodology has the potential to facilitate decision-making and resource optimization in CHS, enabling total quality management and precise benchmarking initiatives.

Red blood cell storage duration and peri-operative outcomes in paediatric cardiac surgery

BACKGROUND

Prior research on red blood cell (RBC) storage duration and clinical outcomes in paediatric cardiac surgery has shown conflicting results. The purpose of this study was to evaluate whether blood stored for a longer duration is harmful in these patients.

METHODS

We performed a retrospective cohort study of paediatric patients undergoing cardiac surgery at our institution between January 2011 and June 2015. Patients were stratified based on whether they were transfused RBCs stored for ≤15 days (fresher blood) or >15 days (older blood). The primary outcome was composite morbidity, with prolonged length of stay (LOS) as a secondary outcome. Subgroup analyses were performed after stratification by RBC transfusion volume (≤2 vs. >2 RBC units). Multivariable logistic regression models were used to assess the impact of RBC storage duration on composite morbidity and prolonged LOS.

RESULTS

Of 461 patients, 122 (26·5%) received fresher blood and 339 (73·5%) received older blood. The overall rate of composite morbidity was 18·0% (n = 22) for patients receiving fresher blood and 13·6% (n = 46) for patients receiving older blood (P = 0·24). In the risk-adjusted model, patients receiving older blood did not exhibit an increased risk of composite morbidity (OR: 0·74, 95% CI: 0·37-1·47, P = 0·40) or prolonged LOS (OR: 0·72, 95% CI: 0·38-1·35, P = 0·30) compared to patients receiving fresher blood. Similar results were seen after stratification by RBC transfusion volume.

CONCLUSIONS

Transfusing RBCs stored for a longer duration was not associated with an increased risk of morbidity or prolonged LOS in paediatric cardiac surgery patients.

Postoperative Hematocrit and Adverse Outcomes in Pediatric Cardiac Surgery Patients: A Cross-Sectional Study From the Society of Thoracic Surgeons and Congenital Cardiac Anesthesia Society Database Collaboration

BACKGROUND

We sought to examine potential associations between pediatric postcardiac surgical hematocrit values and postoperative complications or mortality.

METHODS

A retrospective, cross-sectional study from the Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) and Congenital Cardiac Anesthesia Society Database Module (2014-2019) was completed. Multivariable logistic regression models, adjusting for covariates in the STS-CHSD mortality risk model, were used to assess the relationship between postoperative hematocrit and the primary outcomes of operative mortality or any major complication. Hematocrit was assessed as a continuous variable using linear splines to account for nonlinear relationships with outcomes. Operations after which the oxygen saturation is typically observed to be <92% were classified as cyanotic and ≥92% as acyanotic.

RESULTS

In total, 27,462 index operations were included, with 4909 (17.9%) being cyanotic and 22,553 (82.1%) acyanotic. For cyanotic patients, each 5% incremental increase in hematocrit over 42% was associated with a 1.31-fold (95% confidence interval [CI], 1.10-1.55; P = .003) increase in the odds of operative mortality and a 1.22-fold (95% CI, 1.10-1.36; P < .001) increase in the odds of a major complication. For acyanotic patients, each 5% incremental increase in hematocrit >38% was associated with a 1.45-fold (95% CI, 1.28-1.65; P < .001) increase in the odds of operative mortality and a 1.21-fold (95% CI, 1.14-1.29; P < .001) increase in the odds of a major complication.

CONCLUSIONS

High hematocrit on arrival to the intensive care unit (ICU) is associated with increased operative mortality and major complications in pediatric patients following cardiac surgery.

Developmental outcomes after early surgery for complex congenital heart disease: a systematic review and meta-analysis

AIM

(1) To systematically review the literature on developmental outcomes from infancy to adolescence of children with complex congenital heart disease (CHD) who underwent early surgery; (2) to run a meta-regression analysis on the Bayley Scales of Infant Development, Second Edition Mental Developmental Index and Psychomotor Developmental Index (PDI) of infants up to 24 months and IQs of preschool-aged children to adolescents; (3) to assess associations between perioperative risk factors and outcomes.

METHOD

We searched pertinent literature (January 1990 to January 2019) in PubMed, Embase, CINAHL, and PsycINFO. Selection criteria included infants with complex CHD who had primary surgery within the first 9 weeks of life. Methodological quality, including risk of bias and internal validity, were assessed.

RESULTS

In total, 185 papers met the inclusion criteria; the 100 with high to moderate methodological quality were analysed in detail. Substantial heterogeneity in the group with CHD and in methodology existed. The outcome of infants with single-ventricle CHD was inferior to those with two-ventricle CHD (respectively: average scores for PDI 77 and 88; intelligence scores 92 and 98). Perioperative risk factors were inconsistently associated with developmental outcomes.

INTERPRETATION

The literature on children undergoing surgery in early infancy suggests that infants with a single ventricle are at highest risk of adverse developmental outcomes.

The Risks of Being Tiny: The Added Risk of Low Weight for Neonates Undergoing Congenital Heart Surgery

The aims of this study were (1) to describe the additive risk of performing cardiac surgery in neonates born ≤ 2.0 kg, after accounting for the baseline risks of low birth weight, and (2) to describe the additive risk of being born ≤ 2.0 kg in neonates undergoing cardiac surgery. We used a risk difference analysis in a retrospective cohort, 2006-2016. Neonates born ≤ 2.0 kg undergoing congenital heart surgery during initial postnatal admission were included. Data were standardized alternatingly for birth weight and cardiac surgical risk using national population data to estimate the number of deaths expected had they not required cardiac surgery or were they of normal weight. Of 105 neonates ≤ 2 kg, median birth weight was 1.6 kg (IQR 1.3-1.8 kg). Median gestational age was 33 weeks (IQR 31-35 weeks). Observed operative mortality was 14.3%; 0% for neonates ≤ 1.0 kg (CI 0-33.6%), 20.6% for neonates > 1.0-1.5 kg (CI 8.7-37.9%), and 12.9% for neonates > 1.5-2.0 kg (CI 5.7-23.9%). Among neonates ≤ 2.0 kg not undergoing cardiac surgery, expected mortality was 4.8% (CI 1.6-10.8); cardiac surgery increased the risk of mortality 9.5% (CI 1.7-17.4%). Conversely, the expected risk for normal birth weight neonates undergoing cardiac surgery was 5.7% (CI 2.1-12.0%); low birth weight increased the risk of mortality 8.6% (CI 0.5-16.6%). To continue making advancements in cardiac surgery, we must understand that the rate of mortality observed in normal weight infants is not a realistic target and that, despite advances, the risk attributable to the surgery remains higher among low birth weight patients.

Single Institution Experience With International Referrals for Pediatric Cardiac Surgery

BACKGROUND

Pediatric cardiac surgery in developing countries poses many challenges. The practice of referring patients from abroad via nongovernmental organizations has occurred for many years. We describe our experience with international referrals for pediatric cardiac surgery via Gift of Life Mid-South to the Heart Institute, Le Bonheur Children's Hospital in Memphis, Tennessee.

METHODS

We performed a retrospective descriptive review of data collected in our Society of Thoracic Surgeons Congenital Heart Surgery Database (STS CHSD) along with data from our electronic medical record from January 1, 2007, to December 31, 2017. Available data included patient demographics, diagnoses, surgical procedure, entire inpatient length of stay (LOS), complications, and operative mortality. Cardiac surgeries were grouped according to the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Congenital Heart Surgery Mortality Categories (STAT Mortality Categories). Complications were defined according to the STS CHSD.

RESULTS

In this retrospective descriptive study, case complexity level varied; however, 38% cardiac surgeries were in STAT Mortality Category 3 or 4. Honduras was the most common referral source with a total of 18 countries represented. Operative mortality remained very low (1 [1.4%] of 71 cardiac surgeries) despite patients being referred beyond infancy. There were an increasing number of complications and longer inpatient LOS (with greater variance) in STAT Mortality Category 4.

CONCLUSIONS

International patients referred for congenital heart surgery can be successfully treated with an acceptable mortality rate despite late referrals. Inpatient LOS is related to surgical complexity. Follow-up studies are needed to determine the long-term outcomes of these patients.

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

OBJECTIVE

To determine prevalence of and risk factors for infection in pediatric subjects with congenital heart disease status postcardiotomy supported on extracorporeal membrane oxygenation, as well as outcomes of these subjects.

DESIGN

Retrospective cohort from the Extracorporeal Life Support Organization.

SETTING

U.S. and international medical centers providing care to children with congenital heart disease status postcardiotomy.

PATIENTS

Critically ill pediatric subjects less than 8 years old admitted to medical centers between January 1, 2013, and December 31, 2015, who underwent cardiac surgery for congenital heart disease and required extracorporeal membrane oxygenation support within the first 14 postoperative days. Subjects were excluded if they underwent orthotopic heart transplantation, required preoperative extracorporeal membrane oxygenation, and had more than one postoperative extracorporeal membrane oxygenation run.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 1,314 extracorporeal membrane oxygenation subject encounters in the Extracorporeal Life Support Organization registry met inclusion criteria. Neonates comprised 53% (n = 696) of the cohort, whereas infants made up 33% (n = 435). Of the 994 subjects with Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery categorizable surgery, 33% (n = 325) were in Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category 4 and 23% (n = 231) in Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery category 5. While on extracorporeal membrane oxygenation, 229 subjects (17%) acquired one or more extracorporeal membrane oxygenation-related infections, which represents an occurrence rate of 67 infections per 1,000 extracorporeal membrane oxygenation days. Gram-negative (62%) and Gram-positive (42%) infections occurred most commonly. Forty percent had positive blood cultures. Infants and children were at higher infection risk compared with neonatal subjects; subjects undergoing less complex surgery had higher infection rates. Unadjusted survival to hospital discharge was lower in infected subjects compared with noninfected subjects (43% vs 51%; p = 0.01). After adjusting for confounders via propensity matching, we identified no significant mortality difference between infected and noninfected subjects.

CONCLUSIONS

Neonatal and pediatric subjects in this study have a high rate of acquired infection. Infants and children were at higher infection risk compared with neonatal subjects. There was not, however, a significant association between extracorporeal membrane oxygenation-related infection and survival to hospital discharge after propensity matching.

The Impact of Dedicated Cardiac Intensive Care Units on Outcomes in Pediatric Cardiac Surgery: A Virtual Pediatric Systems Database Analysis

Care of children undergoing cardiac surgery occurs in dedicated cardiac intensive care units (CICU) or mixed intensive care units. In this article, we analyzed data from Virtual Pediatric Systems (VPS, LLC) database (2009-2014) for children < 18 years of age undergoing cardiac surgery, classified according to Society of Thoracic Surgery-European Association of Cardiothoracic Surgery (STS-EACTS) risk category. We had 25,052 (52%) patients in 53 mixed units (mortality rate, 2.99%), and 22,762 (48%) patients in 19 dedicated CICUs (mortality rate, 2.62%). There was a direct relationship between STS-EACTS risk category and death rate in both units. By multivariable logistic and linear regression, there was no difference in mortality between mixed unit and CICU death rates within STS-EACTS risk categories. We found no difference in outcomes for children undergoing cardiac surgery based on the unit type (dedicated CICU or mixed unit).

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

OBJECTIVES

Current central venous catheter utilization in patients within pediatric cardiac ICUs is not well elucidated. We aim to describe current use of central venous catheters in a multi-institutional cohort and to explore the prevalence and risk factors for central line-associated thrombosis and central line-associated bloodstream infections.

DESIGN

Observational analysis.

SETTING

Pediatric Cardiac Critical Care Consortium hospitals.

PATIENTS

Hospitalizations with at least one cardiac ICU admission from October 2013 to July 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were 17,846 hospitalizations and 69% included greater than or equal to one central venous catheter. Central venous catheter use was higher in younger patients (86% neonates). Surgical hospitalizations included at least one central venous catheter 88% of the time compared with 35% of medical hospitalizations. The most common location for central venous catheters was internal jugular (46%). Central venous catheters were in situ a median of 4 days (interquartile range, 2-10). There were 248 hospitalizations (2% overall, 1.8% medical, and 2.1% surgical) with at least one central line-associated thrombosis (271 total thromboses). Thrombosis was diagnosed at a median of 7 days (interquartile range, 4-14) after catheter insertion. There were 127 hospitalizations (1% overall, 1.4% medical, and 1% surgical) with at least one central line-associated bloodstream infection (136 total infections) with no association with catheter type or location. Central line-associated bloodstream infection was diagnosed at a median of 19 days (interquartile range, 8-36) after catheter insertion. Significant risk factors for central line-associated thrombosis and central line-associated bloodstream infection were younger age, greater surgical complexity, and total catheter days.

CONCLUSIONS

Utilization of central venous catheters in pediatric cardiac ICUs differs according to indication for hospitalization. Although thrombosis and central line-associated bloodstream infection are infrequent complications of central venous catheter use in cardiac ICU patients, these events can have important short- and long-term consequences for patients. Total central venous catheter line days were the only modifiable risk factor identified. Future study must focus on understanding central venous catheter practices in high-risk patient subgroups that reduce the prevalence of thrombosis and central line-associated bloodstream infection.

Overcoming underpowering: Trial simulations and a global rank end point to optimize clinical trials in children with heart disease

BACKGROUND

Randomized controlled trials (RCTs) in children with heart disease are challenging and therefore infrequently performed. We sought to improve feasibility of perioperative RCTs for this patient cohort using data from a large, multicenter clinical registry. We evaluated potential enrollment and end point frequencies for various inclusion cohorts and developed a novel global rank trial end point. We then performed trial simulations to evaluate power gains with the global rank end point and with use of planned covariate adjustment as an analytic strategy.

METHODS

Data from the Society of Thoracic Surgery-Congenital Heart Surgery Database (STS-CHSD, 2011-2016) were used to support development of a consensus-based global rank end point and for trial simulations. For Monte Carlo trial simulations (n = 50,000/outcome), we varied the odds of outcomes for treatment versus placebo and evaluated power based on the proportion of trial data sets with a significant outcome (P < .05).

RESULTS

The STS-CHSD study cohort included 35,967 infant index cardiopulmonary bypass operations from 103 STS-CHSD centers, including 11,411 (32%) neonatal cases and 12,243 (34%) high-complexity (Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality category ≥4) cases. In trial simulations, study power was 21% for a mortality-only end point, 47% for a morbidity and mortality composite, and 78% for the global rank end point. With covariate adjustment, power increased to 94%. Planned covariate adjustment was preferable to restricting to higher-risk cohorts despite higher event rates in these cohorts.

CONCLUSIONS

Trial simulations can inform trial design. Our findings, including the newly developed global rank end point, may be informative for future perioperative trials in children with heart disease.

Impact of Different Cardiopulmonary Bypass Strategies on Renal Injury After Pediatric Heart Surgery

BACKGROUND

The purpose of this study is to compare the incidence and severity of acute kidney injury (AKI) after open heart surgery in neonates and infants for two different cardiopulmonary bypass (CPB) strategies.

METHODS

In all, 151 infants undergoing cardiac surgery were prospectively enrolled between June 2017 and June 2018 at two centers, one using conventional CPB (2.4 L · min^-1 · m^-2, 150 mL · kg^-1 · min^-1) with reduction of flow rates with moderate hypothermia and with a targeted hematocrit greater than 25% (center 1, n = 91), and the other using higher bypass flow rates (175 to 200 mL · kg^-1 · min^-1) and higher minimum hematocrit (greater than 32%) CPB (center 2, n = 60). The primary endpoint was the incidence of postoperative AKI as defined by Acute Kidney Injury Network criteria and risk factors associated with AKI.

RESULTS

Preoperative characteristics and complexity of surgery were comparable between centers. The overall incidence of early postoperative AKI was 10.6% (16 of 151), with 15.4% (14 of 91) in center 1 and 3.3% (2 of 60) in center 2 (P = .02). Mean lowest flow rates on CPB were 78 mL · kg^-1 · min^-1 vs 118 mL · kg^-1 · min^-1 and mean highest hematocrit on separation from CPB were 33% vs 43% at center 1 and 2, respectively (P < .001). Center 1 used less packed red blood cells but more fresh frozen plasma than center 2 (P = .001). By multivariate analysis, only lower flows on CPB (78 vs 96 mL · kg^-1 · min^-1, P = .043) and lower hematocrit at the end of CPB (33% vs 37%, P = .007) were associated with AKI.

CONCLUSIONS

In this contemporary comparative study, higher flow rates and higher hematocrit during cardiopulmonary bypass were associated with better preservation of renal function.

Cerebral oxygenation during pediatric congenital cardiac surgery and its association with outcome: a retrospective observational study

Purpose

Non-invasive cerebral oxygen saturation (ScO₂) monitoring is an established tool in the intraoperative phase of pediatric congenital cardiac surgery (CCS). This study investigated the association between ScO₂ and postoperative outcome by investigating both baseline ScO₂ values and intraoperative desaturations from baseline.

Methods

All CCS procedures performed in the period 2010-2017 in our institution in which ScO₂ was monitored were included in this historical cohort study. Baseline ScO₂ was determined after tracheal intubation, before surgical incision. Subgroups were based on cardiac pathology and degree of intracardiac shunting. Poor outcome was defined based on length of stay (LOS) in the intensive care unit (ICU)/hospital, duration of mechanical ventilation (MV), and 30-day mortality. Intraoperatively, ScO₂ total time below baseline (TBBL) and ScO₂ time-weighted average (TWA) were calculated.

Results

Data from 565 patients were analyzed. Baseline ScO₂ was significantly associated with LOS in ICU (odds ratio [OR] per percentage decrease in baseline ScO₂, 0.95; 95% confidence interval [CI], 0.93 to 0.97; P < 0.001), with LOS in hospital (OR, 0.93; 95% CI, 0.91 to 0.96; P < 0.001), with MV duration (OR, 0.92; 95% CI, 0.90 to 0.95; P < 0.001) and with 30-day mortality (OR, 0.94; 95% CI, 0.91 to 0.98; P = 0.007). Cerebral oxygen saturation TWA had no associations, while ScO₂ TBBL had only a small association with LOS in ICU (OR, 1.02; 95% CI, 1.01 to 1.03; P < 0.001), MV duration (OR,1.02; 95% CI, 1.01 to 1.03; P = 0.002), and LOS in hospital (OR, 1.02; 95% CI, 1.01 to 1.04; P < 0.001).

Conclusion

In pediatric patients undergoing cardiac surgery, low baseline ScO₂ values measured after tracheal intubation were associated with several adverse postoperative outcomes. In contrast, the severity of actual intraoperative cerebral desaturation was not associated with postoperative outcomes. Baseline ScO₂ measured after tracheal intubation may help identify patients at increased perioperative risk.

Improvement in Pediatric Cardiac Surgical Outcomes Through Interhospital Collaboration

BACKGROUND

Patients undergoing complex pediatric cardiac surgery remain at considerable risk of mortality and morbidity, and variation in outcomes exists across hospitals. The Pediatric Cardiac Critical Care Consortium (PC4) was formed to improve the quality of care for these patients through transparent data sharing and collaborative learning between participants.

OBJECTIVES

The purpose of this study was to determine whether outcomes improved over time within PC4.

METHODS

The study analyzed 19,600 hospitalizations (18 hospitals) in the PC4 clinical registry that included cardiovascular surgery from August 2014 to June 2018. The primary exposure was 2 years of PC4 participation; this provided adequate time for hospitals to accrue data and engage in collaborative learning. Aggregate case mix-adjusted outcomes were compared between the first 2 years of participation (baseline) and all months post-exposure. We also evaluated outcomes from the same era in a cohort of similar, non-PC4 hospitals.

RESULTS

During the baseline period, there was no evidence of improvement. We observed significant improvement in the post-exposure period versus baseline for post-operative intensive care unit mortality (2.1% vs. 2.7%; 22% relative reduction [RR]; p = 0.001), in-hospital mortality (2.5% vs. 3.3%; 24% RR; p = 0.001), major complications (10.1% vs. 11.5%; 12% RR; p < 0.001), intensive care unit length of stay (7.3 days vs. 7.7 days; 5% RR; p < 0.001), and duration of ventilation (61.3 h vs. 70.6 h; 13% RR; p = 0.01). Non-PC4 hospitals showed no significant improvement in mortality, complications, or hospital length of stay.

CONCLUSIONS

This analysis demonstrates improving cardiac surgical outcomes at children's hospitals participating in PC4. This change appears unrelated to secular improvement trends, and likely reflects PC4's commitment to transparency and collaboration.

ST2 Predicts Risk of Unplanned Readmission Within 1 Year After Pediatric Congenital Heart Surgery

BACKGROUND

Approximately 10% to 20% of children are readmitted after congenital heart surgery. Very little is known about biomarkers as predictors of risk of unplanned readmission after pediatric congenital heart surgery. Novel cardiac biomarker ST2 may be associated with risk of unplanned readmission. ST2 concentrations are believed to reflect cardiovascular stress and fibrosis. Our objective was to explore the relationship between pre- and postoperative ST2 biomarker levels and risk of readmission within 1 year after congenital heart surgery.

METHODS

We prospectively enrolled pediatric patients aged < 18 years who underwent at least 1 congenital heart operation at Johns Hopkins Hospital from 2010 to 2014. Plasma samples were collected immediately before surgery and at the end of bypass. We used Kaplan-Meier survival analysis and multivariable Cox regression models to adjust for variables used in The Society of Thoracic Surgeons Congenital Heart Surgery Database mortality risk model.

RESULTS

Of our cohort of 145 patients, we found 39 children with readmissions within 365 days. The median time to unplanned readmission was 54 days (interquartile range, 10-153). Kaplan-Meier analysis demonstrated a significant difference across terciles of pre- and postoperative ST2 biomarker levels. After adjustment, elevated serum levels of ST2 measured preoperatively and postoperatively were associated with increased risk of readmission (hazard ratio, 2.5-3.7; all P < .05).

CONCLUSIONS

Elevated levels of ST2 are significantly associated with increased risk of unplanned readmission within 1 year after pediatric congenital heart surgery. Novel serum biomarker ST2 can be used for risk stratification or estimating postsurgical prognosis.

Association between preoperative respiratory support and outcomes in paediatric cardiac surgery

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

Variation in Case-Mix Adjusted Unplanned Pediatric Cardiac ICU Readmission Rates

OBJECTIVES

To identify modifiable factors leading to unplanned readmission and characterize differences in adjusted unplanned readmission rates across hospitals.

DESIGN

Retrospective cohort study using prospectively collected clinical registry data SETTING:: Pediatric Cardiac Critical Care Consortium clinical registry.

PATIENTS

Patients admitted to a pediatric cardiac ICU at Pediatric Cardiac Critical Care Consortium hospitals.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We examined pediatric cardiac ICU encounters in the Pediatric Cardiac Critical Care Consortium registry from October 2013 to March 2016. The primary outcomes were early (< 48 hr from pediatric cardiac ICU transfer) and late (2-7 d) unplanned readmission. Generalized logit models identified independent predictors of unplanned readmission. We then calculated observed-to-expected ratios of unplanned readmission and identified higher-than or lower-than-expected unplanned readmission rates for those with an observed-to-expected ratios greater than or less than 1, respectively, and a 95% CI that did not cross 1. Of 11,301 pediatric cardiac ICU encounters (16 hospitals), 62% were surgical, and 18% were neonates. There were 175 (1.6%) early unplanned readmission, and 300 (2.7%) late unplanned readmission, most commonly for respiratory (31%), or cardiac (28%) indications. In multivariable analysis, unique modifiable factors were associated with unplanned readmission. Although shorter time between discontinuation of vasoactive infusions and pediatric cardiac ICU transfer was associated with early unplanned readmission, nighttime discharge was independently associated with a greater likelihood of late unplanned readmission. Two hospitals had lower-than-expected unplanned readmission in both the early and late categories, whereas two other hospitals were higher-than-expected in both.

CONCLUSIONS

This analysis demonstrated time from discontinuation of critical care therapies to pediatric cardiac ICU transfer as a significant, modifiable predictor of unplanned readmission. We identified two hospitals with lower-than-expected adjusted rates of both early and late unplanned readmission, suggesting that their systems are well designed to prevent unplanned readmission. This offers the possibility of disseminating best practices to other hospitals through collaborative learning.

Higher Flow on Cardiopulmonary Bypass in Pediatrics Is Associated With a Lower Incidence of Acute Kidney Injury

Adequate perfusion is of paramount concern during cardiopulmonary bypass (CPB) and different methodologies are employed to optimize oxygen delivery. Temperature, hematocrit, and cardiac index (CI) are all modulated during CPB to ensure appropriate support. This study examines 2 different perfusion strategies and their impact on various outcome measures including acute kidney injury (AKI), urine output on CPB, ICU length of stay, time to extubation, and mortality. Predicated upon surgeon preference, the study institution employs 2 different perfusion strategies (PS) during congenital cardiac surgery requiring CPB. One method utilizes a targeted 2.4 L/min/m² CI and nadir hematocrit of 28% (PS1), the other a 3.0 L/min/m² CI with a nadir hematocrit of 25% (PS2). This study retrospectively examines CPB cases during which the 2 perfusion strategies were applied to determine potential differences in packed red blood cell administration, urine output during CPB, AKI post-CPB as defined by the KDIGO criteria, and operative survival as defined by the Society of Thoracic Surgeons. Significant differences were found in urine output while on CPB (P < 0.01) and all combined stages of postoperative AKI (P = 0.01) with the PS2 group faring better in both measures. No significant difference was found between the 2 groups for packed red blood cell administration, mortality, time to extubation, or ICU length of stay. Avoiding a nadir hematocrit less than 25% has been well established but maintaining anything greater than that may not be necessary to achieve adequate oxygen delivery on CPB. Our results indicate that higher CI and oxygen delivery on CPB are associated with a lower rate of AKI and this may be achieved with increased flow rather than increasing the hematocrit thus avoiding unnecessary transfusion.

Biomarkers improve prediction of 30-day unplanned readmission or mortality after paediatric congenital heart surgery

OBJECTIVE

To evaluate the association between novel pre- and post-operative biomarker levels and 30-day unplanned readmission or mortality after paediatric congenital heart surgery.

METHODS

Children aged 18 years or younger undergoing congenital heart surgery (n = 162) at Johns Hopkins Hospital from 2010 to 2014 were enrolled in the prospective cohort. Collected novel pre- and post-operative biomarkers include soluble suppression of tumorgenicity 2, galectin-3, N-terminal prohormone of brain natriuretic peptide, and glial fibrillary acidic protein. A model based on clinical variables from the Society of Thoracic Surgery database was developed and evaluated against two augmented models.

RESULTS

Unplanned readmission or mortality within 30 days of cardiac surgery occurred among 21 (13%) children. The clinical model augmented with pre-operative biomarkers demonstrated a statistically significant improvement over the clinical model alone with a receiver-operating characteristics curve of 0.754 (95% confidence interval: 0.65-0.86) compared to 0.617 (95% confidence interval: 0.47-0.76; p-value: 0.012). The clinical model augmented with pre- and post-operative biomarkers demonstrated a significant improvement over the clinical model alone, with a receiver-operating characteristics curve of 0.802 (95% confidence interval: 0.72-0.89; p-value: 0.003).

CONCLUSIONS

Novel biomarkers add significant predictive value when assessing the likelihood of unplanned readmission or mortality after paediatric congenital heart surgery. Further exploration of the utility of these novel biomarkers during the pre- or post-operative period to identify early risk of mortality or readmission will aid in determining the clinical utility and application of these biomarkers into routine risk assessment.