Successful Implementation of Enhanced Recovery After Surgery (ERAS) in Paediatric Cardiac Surgery in Australia.

BACKGROUND & AIM: Fast-track or enhanced recovery after surgery (ERAS) is a care pathway for surgical patients based on a multidisciplinary team approach aimed at optimising recovery without increasing risk with protocols based on scientific evidence, which is monitored continuously to ensure compliance and improvement. These protocols have been shown to reduce the duration of postoperative mechanical ventilation and intensive care unit (ICU) length of stay (LOS) following paediatric cardiac surgery. We present the first structured implementation of ERAS in paediatric cardiac surgery in Australia. METHODS: All patients enrolled in the ERAS pathway between October 2019 and July 2023 were identified. Demographic and perioperative data were collected retrospectively from hospital records for patients operated before June 2021 and prospectively from June 2021. A control group (non-ERAS) was identified using propensity matching from patients who underwent similar procedures and were not enrolled in the ERAS pathway (prior to October 2019). Patients were matched for age, weight, and comprehensive Aristotle score. Outcomes of interest were duration of postoperative mechanical ventilation, ICU LOS, readmission to the ICU, hospital LOS, cardiac reintervention rate, postoperative complication rate, and number of 30-day readmissions. RESULTS: Of 1,084 patients who underwent cardiac surgery during the study period (October 2019-July 2023), 121 patients (11.2%) followed the ERAS pathway. The median age at the time of surgery was 4.8 years (interquartile range [IQR] 2.8-8.8 years). The most common procedure was the closure of atrial septal defect (n=58, 47.9%). The median cardiopulmonary bypass and cross-clamp times were 40 min (IQR 28-53.5 minutes) and 24.5 min (IQR 13-34 minutes) respectively. The majority were extubated in the operating theatre (n=108, 89.3%). The median ICU and hospital LOS were 4.5 hrs (IQR 4.1-5.6 hours) and 4 days (IQR 4-5 days) respectively. None of the patients required readmission to the ICU within 24 hrs of discharge from the ICU. Three (3) patients (2.5%) required reintervention. When compared with the non-ERAS group, the duration of postoperative mechanical ventilation, ICU and hospital LOS were significantly lower in the ERAS group. There was no significant difference in the ICU readmission rate, reintervention rate, complication rate, and number of 30-day readmissions between both groups. CONCLUSIONS: ERAS after paediatric cardiac surgery is feasible and safe in select patients with low preoperative risk. This pathway reduces the duration of postoperative mechanical ventilation, ICU and hospital LOS without increasing risks, enabling the optimisation of resources.

Australian National Standards of Care for Childhood-onset Heart Disease (CoHD Standards). 1st Edition.

These first Australian National Standards of Care for Childhood-onset Heart Disease (CoHD Standards) have been developed to inform the healthcare requirements for CoHD services and enable all Australian patients, families and carers impacted by CoHD (paediatric CoHD and adult congenital heart disease [ACHD]) to live their best and healthiest lives. The CoHD Standards are designed to provide the clarity and certainty required for healthcare services to deliver excellent, comprehensive, inclusive, and equitable CoHD care across Australia for patients, families and carers, and offer an iterative roadmap to the future of these services. The CoHD Standards provide a framework for excellent CoHD care, encompassing key requirements and expectations for whole-of-life, holistic and connected healthcare service delivery. The CoHD Standards should be implemented in health services in conjunction with the National Safety and Quality Health Service Standards developed by the Australian Commission on Safety and Quality in Health Care. All healthcare services should comply with the CoHD Standards, as well as working to their organisation's or jurisdiction's agreed clinical governance framework, to guide the implementation of structures and processes that support safe care.

High-Speed On-Site Deep Learning-Based FFR-CT Algorithm: Evaluation Using Invasive Angiography as the Reference Standard.

BACKGROUND. Estimation of fractional flow reserve from coronary CTA (FFR-CT) is an established method of assessing the hemodynamic significance of coronary lesions. However, clinical implementation has progressed slowly, partly because of off-site data transfer with long turnaround times for results. OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of FFR-CT computed on-site with a high-speed deep learning-based algorithm with invasive hemodynamic indexes as the reference standard. METHODS. This retrospective study included 59 patients (46 men, 13 women; mean age, 66.5 ± 10.2 years) who underwent coronary CTA (including calcium scoring) followed within 90 days by invasive angiography with invasive fractional flow reserve (FFR) and/or instantaneous wave-free ratio measurements from December 2014 to October 2021. Coronary artery lesions were considered to have hemodynamically significant stenosis in the presence of invasive FFR of 0.80 or less and/or instantaneous wave-free ratio of 0.89 or less. A single cardiologist evaluated the CTA images using an on-site deep learning-based semiautomated algorithm entailing a 3D computational flow dynamics model to determine FFR-CT for coronary artery lesions detected with invasive angiography. Time for FFR-CT analysis was recorded. FFR-CT analysis was repeated by the same cardiologist in 26 randomly selected examinations and by a different cardiologist in 45 randomly selected examinations. Diagnostic performance and agreement were assessed. RESULTS. A total of 74 lesions were identified with invasive angiography. FFR-CT and invasive FFR had strong correlation (r = 0.81) and, in Bland-Altman analysis, bias of 0.01 and 95% limits of agreement of -0.13 to 0.15. FFR-CT had AUC for hemodynamically significant stenosis of 0.975. At a cutoff of 0.80 or less, FFR-CT had 95.9% accuracy, 93.5% sensitivity, and 97.7% specificity. In 39 lesions with severe calcifications (≥ 400 Agatston units), FFR-CT had AUC of 0.991 and at a cutoff of 0.80, 94.7% sensitivity, 95.0% specificity, and 94.9% accuracy. Mean analysis time per patient was 7 minutes 54 seconds. Intraobserver agreement (intraclass correlation coefficient, 0.85; bias, -0.01; 95% limits of agreement, -0.12 and 0.10) and interobserver agreement (intraclass correlation coefficient, 0.94; bias, -0.01; 95% limits of agreement, -0.08 and 0.07) were good to excellent. CONCLUSION. A high-speed on-site deep learning-based FFR-CT algorithm had excellent diagnostic performance for hemodynamically significant stenosis with high reproducibility. CLINICAL IMPACT. The algorithm should facilitate implementation of FFR-CT technology into routine clinical practice.

Geographical challenges and inequity of healthcare access for high-risk paediatric heart disease.

BACKGROUND: Geographical context is an important consideration for health system design to promote equality in access to care for patients with childhood heart disease (CHD), particularly those living in regional, rural, and remote areas. To help inform future policy and practice recommendations, this study aimed to (i) describe the geographic distribution of high-risk CHD patients accessing an Australian state-wide specialist service and (ii) estimate travel time for accessing healthcare via general practitioners (primary), nearest paediatric centre (secondary) and specialist paediatric cardiac centre (tertiary). METHODS: Participants included a cohort of children (0-18 year) who accessed state-wide specialist CHD services over a 3-year period (2019-2021) in Queensland, Australia. Locations for patient residence, general practitioner, closest paediatric centre and tertiary cardiac centre were mapped using geographical information system (GIS) software (ArcGIS Online). Travel distance and times were estimated using a Google Maps Application Programming Interface (API). RESULTS: 1019 patients (median age 3.8 years) had cardiac intervention and were included in the sample. Of this cohort, 30.2% lived outside the heavily urbanised South East Queensland (SEQ) area where the tertiary centre is located. These patients travel substantially further and longer to access tertiary level care (but not secondary or primary level care) compared to those in SEQ. Median distance for patients residing outside SEQ to access tertiary care was 953 km with a travel time of 10 h 43 min. This compares to 5.5 km to the general practitioner and 20.6 km to a paediatric service (8.9 and 54 min respectively). CONCLUSION: This geographical mapping of CHD services has demonstrated a key challenge inherent in providing specialist cardiac care to children in a large state-based healthcare system. A significant proportion of high-risk patients live large distances from tertiary level care. The greater accessibility of primary care services highlights the importance of supporting primary care physicians outside metropolitan areas to acquire or build the ability and capacity to care for children with CHD. Strengthening local primary and secondary services not only has the potential to improve the outcomes of high-risk patients, but also to reduce costs and burden associated with potentially avoidable travel from regional, rural, or remote areas to access specialist CHD services.

Clinical stakeholder preferences for paediatric cardiac surgery outcome reporting in Australia and New Zealand.

BACKGROUND: Outcome reporting is an essential element of quality assurance. Evaluation of the information needs of stakeholders of outcome reporting is limited. This study aimed to examine stakeholder preferences for the content, format, and dissemination of paediatric cardiac surgery performance data in Australia and New Zealand. METHODS: Semi-structured interviews were completed with a purposive sample of Queensland stakeholders to evaluate their attitudes and expectations regarding reporting of paediatric cardiac surgery outcomes. The interviews were audio-recorded and transcribed. Two researchers used an interpretive description approach to analyse the transcripts qualitatively. RESULTS: Nineteen stakeholders were interviewed including fifteen clinicians, four parents, one hospital administrator, and one consumer advocate were interviewed. Mortality was highlighted as the area of greatest interest in reports by clinical and consumer groups. The majority preferred hospital rather than individual/clinician-level reporting. Annual reports were preferred by clinicians who requested reports be distributed electronically. CONCLUSIONS: The evidence generated from outcome reporting in paediatric cardiac surgery is highly desired by clinicians, administrators, parents, families, and advocacy groups. Clinical users prefer information to assist in clinical decision-making, while families seek personalised information at crucial time points in their clinical journey.

Cardiopulmonary bypass in a child with severe Factor XII deficiency.

Factor XII (FXII) deficiency presents as a prolonged activated partial thromboplastin time (aPTT) but is not associated with clinically significant bleeding. Activated clotting time (ACT) is used routinely to monitor anticoagulation with unfractionated heparin in patients undergoing cardiopulmonary bypass (CPB). The coagulation activator reagents in most ACT tests are dependent on adequate FXII concentrations to initiate contact factor coagulation pathways. We report the case of a 14.7 kg girl undergoing CPB with a pre-admission FXII concentration of <1% and aPTT >200 seconds. The child was transfused with fresh-frozen plasma to replenish FXII, allowing safe ACT monitoring of heparin anticoagulation throughout CPB.

Outcomes After Stage I Norwood Palliation in a Recently Established Program Can Achieve Results Similar to Longer Established Services.

BACKGROUND: Infants with hypoplastic left heart syndrome (HLHS) or similar single ventricle cardiac lesions require a three-stage surgical approach, the first step being the Stage I Norwood procedure. The Queensland Children's Hospital (QCH) in Australia is a tertiary hospital providing the only cardiac surgical service to children in Queensland and northern New South Wales. OBJECTIVE: To review the centre's outcomes of Norwood procedures performed in the last 6 years. MATERIALS AND METHODS: We retrospectively evaluated all infants undergoing the stage I Norwood procedure between January 2015 and August 2021. Mortality, intensive care length of stay, events of cardiac arrest following surgery and duration of mechanical ventilation were calculated and analysed for subgroups depending on type of pulmonary shunt type (right-ventricle-to-pulmonary-artery shunt [RVPAS] vs the modified Blalock-Taussig shunt [MBTS]). RESULTS: Forty-nine (49) patients were included. Overall survival to stage two operation (Glenn) was 90%. Both shunts were used evenly with the RVPA conduit preferred for HLHS and the MBTS largely chosen for hypoplastic left heart variants. In univariable analysis there was no difference in cardiac arrest or mortality rate for the patient with a RVPAS compared to the patient with a MBTS. CONCLUSION: We show that a recently established Norwood program can achieve results that are comparable to those reported by longer established centres, and the international literature.

Balloon dilatation versus surgical valvotomy for congenital aortic stenosis: a propensity score matched study.

BACKGROUND: Balloon valvuloplasty and surgical aortic valvotomy have been the treatment mainstays for congenital aortic stenosis in children. Choice of intervention often differs depending upon centre bias with limited relevant, comparative literature. OBJECTIVES: This study aims to provide an unbiased, contemporary matched comparison of these balloon and surgical approaches. METHODS: Retrospective analysis of patients with congenital aortic valve stenosis who underwent balloon valvuloplasty (Queensland Children's Hospital, Brisbane) or surgical valvotomy (Royal Children's Hospital, Melbourne) between 2005 and 2016. Patients were excluded if pre-intervention assessment indicated ineligibility to either group. Propensity score matching was performed based on age, weight, and valve morphology. RESULTS: Sixty-five balloon patients and seventy-seven surgical patients were included. Overall, the groups were well matched with 18 neonates/25 infants in the balloon group and 17 neonates/28 infants in the surgical group. Median age at balloon was 92 days (range 2 days - 18.8 years) compared to 167 days (range 0 days - 18.1 years) for surgery (rank-sum p = 0.08). Mean follow-up was 5.3 years. There was one late balloon death and two early surgical deaths due to left ventricular failure. There was no significant difference in freedom from reintervention at latest follow-up (69% in the balloon group and 70% in the surgical group, p = 1.0). CONCLUSIONS: Contemporary analysis of balloon aortic valvuloplasty and surgical aortic valvotomy shows no difference in overall reintervention rates in the medium term. Balloon valvuloplasty performs well across all age groups, achieving delay or avoidance of surgical intervention.

Neonatal Kawasaki syndrome presenting as out of hospital cardiac arrest rescued by extracorporeal cardiopulmonary resuscitation.

A 7-week-old girl presented in severe shock to a local emergency department. During transfer to the quaternary pediatric hospital, the child had a cardiac arrest and cardiopulmonary resuscitation was commenced en route. Upon arrival to the pediatric intensive care unit, extracorporeal life support was initiated via trans-sternal cannulation. Chest CT performed after extracorporeal life support cannulation, demonstrated widespread aneurysms and a diagnosis of Kawasaki disease was made. Immunomodulatory therapy with immunoglobulin and glucocorticoid medication was commenced and the child was separated from extracorporeal life support after 48 hours. Our case highlights both an unusual presentation of Kawasaki disease and the role extracorporeal cardiopulmonary resuscitation can play in the treatment of this disease. It describes the youngest reported patient in the literature with Kawasaki disease rescued by extracorporeal cardiopulmonary resuscitation and highlights how extracorporeal life support therapy can facilitate appropriate investigations to resolve diagnostic uncertainty and treat the underlying condition.

Creating a Controlled Arterio-Venous Shunt by Reversing the Extracorporeal Membrane Oxygenation Blood Flow: A Strategy for Weaning Patients Off Veno-Arterial Extracorporeal Membrane Oxygenation.

OBJECTIVES: To assess whether reversing the veno-arterial extracorporeal membrane oxygenation blood flow (thereby creating a controlled arterio-venous shunt) can be used to wean children off extracorporeal membrane oxygenation. The standard practice for weaning patients off VA extracorporeal membrane oxygenation is to gradually reduce the blood flows delivered through the extracorporeal membrane oxygenation pump to a minimum level followed by either insertion of an "arterio-venous bridge" and clamping of the blood flow to the patient or direct decannulation. "Pump controlled retrograde flow trial off" is a technique where the revolutions in the centrifugal pump are reduced to the point where the patient will drive the blood retrograde through the extracorporeal membrane oxygenation circuit, effectively turning the circuit into a controlled arterio-venous shunt. The revolutions per minute control the amount of shunt flow. This eliminates any cardiorespiratory support the extracorporeal membrane oxygenation circuit may provide to the patient. DESIGN: Feasibility study. SETTING: Pediatric intensive care. PATIENTS: Extracorporeal membrane oxygenation-dependent pediatric patients, who were ready for weaning, and possible separation from extracorporeal membrane oxygenation entered the trial. INTERVENTION: Pump controlled retrograde flow trial off. MEASUREMENT AND MAIN RESULTS: During 2016, pump controlled retrograde flow trial off was used in 17 patients, for a total of 23 episodes. One episode was unsuccessful in a patient with a body weight of 2.2 kg, where cardiac output was insufficient to provide blood flow to both body and extracorporeal membrane oxygenation circuit, though from 2.8 kg body weight upward, the technique was tolerated. The duration of pump controlled retrograde flow trial off was 15 minutes to 2.5 hours. Five cases led to a continuation of the extracorporeal membrane oxygenation run, as they were not ready to be decannulated. Fifteen patients were decannulated after the pump controlled retrograde flow trial off. No patient needed to be recommenced on extracorporeal membrane oxygenation after decannulation. CONCLUSIONS: Pump controlled retrograde flow trial off is an easy to use and easily reversible technique to assess patient readiness for separation from extracorporeal membrane oxygenation. Given pump controlled retrograde flow trial off can easily be stopped and-in our experience-is not associated with complications, it lowers the threshold to attempt coming off extracorporeal membrane oxygenation and facilitates accurate assessment of whether a patient will need further ongoing extracorporeal membrane oxygenation support.

Coagulation monitoring correlation with heparin dose in pediatric extracorporeal life support.

OBJECTIVES: Extracorporeal Life Support (ECLS) risks thrombotic and hemorrhagic complications. Optimal anti-coagulation monitoring is controversial. We compared coagulation tests evaluating the heparin effect in pediatric ECLS. METHODS: A retrospective study of children (<18yrs) undergoing ECLS over 12 months in a tertiary pediatric intensive care unit (PICU). Variables included anti-Factor Xa activity (anti-Xa), activated partial thromboplastin time (aPTT), activated clotting time (ACT) and thromboelastogram (TEG®6s) parameters: ratio and delta reaction (R) times (the ratio and difference, respectively, between R times in kaolin assays with and without heparinase). Test results were correlated with unfractionated heparin infusion rate (IU/kg/hr) at the time of sampling. Mean test results of each ECLS run were evaluated according to the presence/absence of complications. RESULTS: Thirty-two ECLS runs (31 patients) generated 695 data-points for correlation. PICU mortality was 22% and the thrombotic complication rate was 66%. The proportion of variation in coagulation test results explained by heparin dose was 13.3% for anti-Xa, 11.9% for ratio R time, and 9.9% for delta R time, compared with <1% for ACT and aPTT. Incorporating individual variation, age and antithrombin activity in a model with heparin dose explained less than 50% of the variation in test results. Correlation varied according to age, day of ECLS run and between individuals, with parallel dose-response lines noted between patients. Significantly lower mean anti-Xa was observed in PICU non-survivors and runs with thrombosis. CONCLUSION: Lower anti-Xa was observed in ECLS runs with complications. Although absolute results from anti-Xa and TEG6®s showed the best correlation with heparin dose, a large proportion of variation in results was unexplained by heparin, while dose response was similar between individuals. Population pharmacokinetic/pharmacodynamic modelling is required, as well as prospective trials to delineate the superior means of adjusting heparin therapy to prevent adverse clinical outcomes.

Upper partial sternal split for pediatric cardiac surgery.

OBJECTIVES: We introduced the use of an upper partial sternal split for pediatric cardiac surgical procedures in our unit in 2016. We report the outcomes of our experience in 51 patients using this approach. METHODS: From February 2016 to September 2022, 51 patients underwent congenital cardiac surgical procedures using an upper partial sternal split including vascular ring repair (n = 20), subaortic membrane (n = 12), ventricular septal defect closure with aortic valve resuspension (n = 9), aortic arch repair (n = 4), pulmonary artery band (n = 2), pulmonary artery sling (n = 1), supravalvular aortic stenosis (n = 1), aortic valve replacement (n = 1), and pulmonary artery plasty (n = 1). The surgical approach involved a midline skin incision, based on the manubrium, followed by an upper manubriotomy. No special surgical instrumentation was required. Median patient age was 2.9 years (IQR 1.3, 6.0); median body weight was 15 kg (IQR 9.8, 20). RESULTS: There was no mortality and no patient required intraoperative conversion to full sternotomy. One patient required re-exploration for bleeding when the incision was converted to a full sternotomy. There were no wound complications in any patient. Twenty-one patients (41%) were extubated on the table and of the remaining 30 patients, 23 patients (76%) were extubated within 24 h of surgery. Eleven patients did not require intensive care unit (ICU) admission. Median ICU and hospital stay was 1 day (IQR 1, 1.25) and 5 days (IQR 4, 8) ,respectively. CONCLUSION: An upper partial sternal split approach is straightforward and can be performed safely with a preferable cosmetic result in selected pediatric cardiac operations.

Early outcomes after post-cardiotomy extracorporeal membrane oxygenation in paediatric patients: a contemporary, binational cohort study.

OBJECTIVES: The aim of this study was to assess the early outcomes and risk factors of paediatric patients requiring extracorporeal membrane oxygenation after cardiac surgery (post-cardiotomy). METHODS: Retrospective binational cohort study from the Australia and New Zealand Congenital Outcomes Registry for Surgery database. All patients younger than 18 years of age who underwent a paediatric cardiac surgical procedure from 1 January 2013 to 31 December 2021 and required post-cardiotomy extracorporeal membrane oxygenation (PC-ECMO) in the same hospital admission were included in the study. RESULTS: Of the 12 290 patients included in the study, 376 patients required post-cardiotomy ECMO (3%). Amongst these patients, hospital mortality was 35.6% and two-thirds of patients experienced a major complication. Hypoplastic left heart syndrome was the most common diagnosis (17%). The Norwood procedure and modified Blalock-Taussig shunts had the highest incidence of requiring PC-ECMO (odds ratio of 10 and 6.8 respectively). Predictors of hospital mortality after PC-ECMO included single-ventricle physiology, intracranial haemorrhage and chylothorax. CONCLUSIONS: In the current era, one-third of patients who required PC-ECMO after paediatric cardiac surgery in Australia and New Zealand did not survive to hospital discharge. The Norwood procedure and isolated modified Blalock-Taussig shunt had the highest incidence of requiring PC-ECMO. Patients undergoing the Norwood procedure had the highest mortality (48%). Two-thirds of patients on PC-ECMO developed a major complication.

Performance of CardioCel in Cardiac Surgery: A Systematic Review.

A systematic review was performed for evaluation of the performance of CardioCel® in cardiac surgery. The review included all studies published from January 2013 to December 2020. We conclude that CardioCel is a strong, flexible tissue substitute with good handling characteristics and a low incidence of thrombosis, aneurysm formation, infection, or structural degeneration. It can be used for a variety of intracardiac and extracardiac repairs of congenital heart defects in all age groups with good durability at mid-term follow-up. However, the use of CardioCel in certain positions requires caution. Information on the long-term performance of CardioCel is lacking.

Nitric Oxide on Extracorporeal Membrane Oxygenation in Neonates and Children (NECTAR Trial): Protocol for a Randomized Controlled Trial.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) provides support for the pulmonary or cardiovascular function of children in whom the predicted mortality risk remains very high. The inevitable host inflammatory response and activation of the coagulation cascade due to the extracorporeal circuit contribute to additional morbidity and mortality in these patients. Mixing nitric oxide (NO) into the sweep gas of ECMO circuits may reduce the inflammatory and coagulation cascade activation during ECMO support. OBJECTIVE: The purpose of this study is to test the feasibility and safety of mixing NO into the sweep gas of ECMO systems and assess its effect on inflammation and coagulation system activation through a pilot randomized controlled trial. METHODS: The Nitric Oxide on Extracorporeal Membrane Oxygenation in Neonates and Children (NECTAR) trial is an open-label, parallel-group, pilot randomized controlled trial to be conducted at a single center. Fifty patients who require ECMO support will be randomly assigned to receive either NO mixed into the sweep gas of the ECMO system at 20 ppm for the duration of ECMO or standard care (no NO) in a 1:1 ratio, with stratification by support type (veno-venous vs veno-arterial ECMO). RESULTS: Outcome measures will focus on feasibility (recruitment rate and consent rate, and successful inflammatory marker measurements), the safety of the intervention (oxygenation and carbon dioxide control within defined parameters and methemoglobin levels), and proxy markers of efficacy (assessment of cytokines, chemokines, and coagulation factors to assess the impact of NO on host inflammation and coagulation cascade activation, clotting of ECMO components, including computer tomography scanning of oxygenators for clot assessments), bleeding complications, as well as total blood product use. Survival without ECMO and the length of stay in the pediatric intensive care unit (PICU) are clinically relevant efficacy outcomes. Long-term outcomes include neurodevelopmental assessments (Ages and Stages Questionnaire, Strength and Difficulties Questionnaire, and others) and quality of life (Pediatric Quality of Life Inventory and others) measured at 6 and 12 months post ECMO cannulation. Analyses will be conducted on an intention-to-treat basis. CONCLUSIONS: The NECTAR study investigates the safety and feasibility of NO as a drug intervention during extracorporeal life support and explores its efficacy. The study will investigate whether morbidity and mortality in patients treated with ECMO can be improved with NO. The intervention targets adverse outcomes in patients who are supported by ECMO and who have high expected mortality and morbidity. The study will be one of the largest randomized controlled trials performed among pediatric patients supported by ECMO. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12619001518156; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=376869. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/43760.

A machine learning approach to predicting 30-day mortality following paediatric cardiac surgery: findings from the Australia New Zealand Congenital Outcomes Registry for Surgery (ANZCORS).

OBJECTIVES: We aim to develop the first risk prediction model for 30-day mortality for the Australian and New Zealand patient populations and examine whether machine learning (ML) algorithms outperform traditional statistical approaches. METHODS: Data from the Australia New Zealand Congenital Outcomes Registry for Surgery, which contains information on every paediatric cardiac surgical encounter in Australian and New Zealand for patients aged <18 years between January 2013 and December 2021, were analysed (n = 14 343). The outcome was mortality within the 30-day period following a surgical encounter, with ∼30% of the observations randomly selected to be used for validation of the final model. Three different ML methods were used, all of which employed five-fold cross-validation to prevent overfitting, with model performance judged primarily by the area under the receiver operating curve (AUC). RESULTS: Among the 14 343 30-day periods, there were 188 deaths (1.3%). In the validation data, the gradient-boosted tree obtained the best performance [AUC = 0.87, 95% confidence interval = (0.82, 0.92); calibration = 0.97, 95% confidence interval = (0.72, 1.27)], outperforming penalized logistic regression and artificial neural networks (AUC of 0.82 and 0.81, respectively). The strongest predictors of mortality in the gradient boosting trees were patient weight, STAT score, age and gender. CONCLUSIONS: Our risk prediction model outperformed logistic regression and achieved a level of discrimination comparable to the PRAiS2 and Society of Thoracic Surgery Congenital Heart Surgery Database mortality risk models (both which obtained AUC = 0.86). Non-linear ML methods can be used to construct accurate clinical risk prediction tools.

Utility of routine chest radiographs after chest drain removal in paediatric cardiac surgical patients-a retrospective analysis of 1076 patients.

OBJECTIVES: Chest drains are routinely placed in children following cardiac surgery. The purpose of this study was to determine the incidence of a clinically relevant pneumothorax and/or pleural effusion after drain removal and to ascertain if a chest radiograph can be safely avoided following chest drain removal. METHODS: This single-centre retrospective cohort study included all patients under 18 years of age who underwent cardiac surgery between January 2015 and December 2019 with the insertion of mediastinal and/or pleural drains. Exclusion criteria were chest drain/s in situ ≥14 days and mortality prior to removal of chest drain/s. A drain removal episode was defined as the removal of ≥1 drains during the same episode of analgesia ± sedation. All chest drains were removed using a standard protocol. Chest radiographs following chest drain removal were reviewed by 2 investigators. RESULTS: In all, 1076 patients were identified (median age: 292 days, median weight: 7.8 kg). There were 1587 drain removal episodes involving 2365 drains [mediastinal (n = 1347), right pleural (n = 598), left pleural (n = 420)]. Chest radiographs were performed after 1301 drain removal episodes [mediastinal (n = 1062); right pleural (n = 597); left pleural (n = 420)]. Chest radiographs were abnormal after 152 (12%) drain removal episodes [pneumothorax (n = 43), pleural effusion (n = 98), hydropneumothorax (n = 11)]. Symptoms/signs were present in 30 (2.3%) patients. Eleven (<1%) required medical management. One required reintubation and 2 required chest drain reinsertion. CONCLUSIONS: The incidence of clinically significant pneumothorax/pleural effusion following chest drain removal after paediatric cardiac surgery is low (<1%). Most patients did not require reinsertion of a chest drain. It is reasonable not to perform routine chest radiographs following chest drain removal in most paediatric cardiac surgical patients.