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Using existing data from clinical registries to support clinical trials and other prospective studies has the potential to improve research efficiency. However, little has been reported about staff experiences and lessons learned from implementation of this method in pediatric cardiology.
We describe the process of using existing registry data in the Pediatric Heart Network Residual Lesion Score Study, report stakeholders’ perspectives, and provide recommendations to guide future studies using this methodology.
The Residual Lesion Score Study, a 17-site prospective, observational study, piloted the use of existing local surgical registry data (collected for submission to the Society of Thoracic Surgeons-Congenital Heart Surgery Database) to supplement manual data collection. A survey regarding processes and perceptions was administered to study site and data coordinating center staff.
Survey response rate was 98% (54/55). Overall, 57% perceived that using registry data saved research staff time in the current study, and 74% perceived that it would save time in future studies; 55% noted significant upfront time in developing a methodology for extracting registry data. Survey recommendations included simplifying data extraction processes and tailoring to the needs of the study, understanding registry characteristics to maximise data quality and security, and involving all stakeholders in design and implementation processes.
Use of existing registry data was perceived to save time and promote efficiency. Consideration must be given to the upfront investment of time and resources needed. Ongoing efforts focussed on automating and centralising data management may aid in further optimising this methodology for future studies.
Satellite imagery indicates that the floating terminus of Pine Island Glacier has changed little in extent over the past two decades. Data on the velocity and thickness of the glacier reveal that calving of 28 ± 4 Gta−1 accounts for only half of the ice input near the grounding line. The apparently steady configuration implies that the remainder of the input is lost by basal melting at a mean rate of 12 ± 3 ma−1. Ocean circulation in Pine Island Bay transports +1°C waters beneath the glacier and temperatures recorded in melt-laden outflows show that heat loss from the ocean is consistent with the requirements of the calculated melt rate. The combination of iceberg calving and basal melting lies at the lower end of estimates for the total accumulation over the catchment basin, drawing into question previous estimates of a significantly positive mass budget for this part of the ice sheet.
Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.
Methods and results
This study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)].
Higher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.
Clinical databases in congenital and paediatric cardiac care provide a foundation for quality improvement, research, policy evaluations and public reporting. Structured audits verifying data integrity allow database users to be confident in these endeavours. We report on the initial audit of the Pediatric Cardiac Critical Care Consortium (PC4) clinical registry.
Materials and methods
Participants reviewed the entire registry to determine key fields for audit, and defined major and minor discrepancies for the audited variables. In-person audits at the eight initial participating centres were conducted during a 12-month period. The data coordinating centre randomly selected intensive care encounters for review at each site. The audit consisted of source data verification and blinded chart abstraction, comparing findings by the auditors with those entered in the database. We also assessed completeness and timeliness of case submission. Quantitative evaluation of completeness, accuracy, and timeliness of case submission is reported.
We audited 434 encounters and 29,476 data fields. The aggregate overall accuracy was 99.1%, and the major discrepancy rate was 0.62%. Across hospitals, the overall accuracy ranged from 96.3 to 99.5%, and the major discrepancy rate ranged from 0.3 to 0.9%; seven of the eight hospitals submitted >90% of cases within 1 month of hospital discharge. There was no evidence for selective case omission.
Based on a rigorous audit process, data submitted to the PC4 clinical registry appear complete, accurate, and timely. The collaborative will maintain ongoing efforts to verify the integrity of the data to promote science that advances quality improvement efforts.
Despite many advances in recent years for patients with critical paediatric and congenital cardiac disease, significant variation in outcomes remains across hospitals. Collaborative quality improvement has enhanced the quality and value of health care across specialties, partly by determining the reasons for variation and targeting strategies to reduce it. Developing an infrastructure for collaborative quality improvement in paediatric cardiac critical care holds promise for developing benchmarks of quality, to reduce preventable mortality and morbidity, optimise the long-term health of patients with critical congenital cardiovascular disease, and reduce unnecessary resource utilisation in the cardiac intensive care unit environment. The Pediatric Cardiac Critical Care Consortium (PC4) has been modelled after successful collaborative quality improvement initiatives, and is positioned to provide the data platform necessary to realise these objectives. We describe the development of PC4 including the philosophical, organisational, and infrastructural components that will facilitate collaborative quality improvement in paediatric cardiac critical care.
An enormous effort is underway worldwide to attempt to detect gravitational waves. If successful, this will open a new frontier in astronomy. An essential portion of this effort is being carried out in Australia by the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA), with research teams working at the Australia National University, University of Western Australia, and University of Adelaide involving scientists and students representing many more institutions and nations. ACIGA is developing ultrastable high-power continuous-wave lasers for the next generation interferometric gravity wave detectors; researching the problems associated with high optical power in resonant cavities; opening frontiers in advanced interferometry configurations, quantum optics, and signal extraction; and is the world's leader in high-performance vibration isolation and suspension design. ACIGA has also been active in theoretical research and modelling of potential astronomical gravitational wave sources, and in developing data analysis detection algorithms. ACIGA has opened a research facility north of Perth, Western Australia, which will be the culmination of these efforts. This paper briefly reviews ACIGA's research activities and the prospects for gravitational wave astronomy in the southern hemisphere.
Extracorporeal cardiopulmonary resuscitation may be defined as the use of extracorporeal membrane oxygenation for the support of patients who do not respond to conventional cardiopulmonary resuscitation. Data from national and international paediatric databases indicate that the use of extracorporeal cardiopulmonary resuscitation is increasing. Guidelines from the American Heart Association suggest that any patient with refractory cardiopulmonary resuscitation and potentially reversible causes of cardiac arrest is a candidate for extracorporeal cardiopulmonary resuscitation. One possible framework for selection of patients for extracorporeal cardiopulmonary resuscitation includes dividing patients on the basis of favourable or unfavourable characteristics. Favourable characteristics include cardiac disease, witnessed event in the intensive care unit, ability to deliver effective cardiopulmonary resuscitation, active patient monitoring present, favourable arterial blood gases, and early institution of extracorporeal membrane oxygenation. Unfavourable characteristics potentially include non-cardiac disease, an unwitnessed cardiac arrest, ineffective cardiopulmonary resuscitation, and severely acidotic arterial blood gases. Considering the significant resources and cost involved in the use of extracorporeal cardiopulmonary resuscitation, its use needs to be critically examined to improve outcomes, assess neurological recovery and quality of life, and help identify populations and other factors that may help guide in the selection of patients for successful extracorporeal cardiopulmonary resuscitation.
The use of extracorporeal membrane oxygenation in infants and children with cardiac disease who develop refractory cardiogenic shock, cyanosis, or cardiac arrest is increasing. Early mortality in children with cardiac disease who require extracorporeal membrane oxygenation remains an important issue, as only 40% of cannulated patients survive to discharge from the hospital. However, it is encouraging that 90% children who are discharged alive from the hospital after extracorporeal membrane oxygenation are still alive at intermediate-term follow-up. Surviving patients are at risk for long-term dysfunction of multiple organ systems related to their underlying cardiac disease, non-cardiac comorbidities, treatment-related complications, and exposure to extracorporeal membrane oxygenation. Among the most important acute complications related to support with extracorporeal membrane oxygenation is injury to the central nervous system, which may contribute to adverse neurodevelopmental outcomes. All of these factors, in turn, influence quality of life. Many survivors remain medically complex related to their underlying cardiac disease, comorbidities, and sequelae of complications acquired over their lifetime. Neurological morbidity clearly plays an important role in approximately one-third of survivors, with significant deficits in approximately 10%. The limited data about quality of life data that are available for survivors of cardiac extracorporeal membrane oxygenation suggests that approximately 15–30% of survivors have at least moderately decreased quality of life. Overall, published data support the ongoing use of support with extracorporeal membrane oxygenation in children with acute cardiac failure, most of whom would die without it. However, programmatic efforts to improve the selection of patients and the preservation of the function of end organs during extracorporeal membrane oxygenation are clearly needed in order to improve long-term outcomes.
Three series of nanostructured, μm thick, Co/Ag composite thin films (13, 39 and 61 volume % Co) were produced by dc magnetron sputtering at various substrate temperatures (100–600°C) to determine their magnetic properties and characterize the microstructure. The films were found to be composed of finely dispersed Ag and Co particles. The film surfaces become rougher as the substrate temperature was increased. The crystal lattice structure of the Co was found to be fcc except at the lower substrate temperatures (<300°C) in the 61 volume % films where it was found to be a mixture of fcc and some hcp. The average diffracting particle size of both the Co and Ag rich phases increase with substrate temperature. The magnetic coercivity of the films reached a maximum value when the Co particle size was between 100–150Å.
Heteropoly acids (HPA) are well known solid acids as well as oxidation catalysts. They find application in both homogeneous and heterogeneous reactions. As catalysts, problems associated with surface area and instability are diminished by supporting the HPA. It has been reported that supporting these materials on oxide substrates or porous carbon materials has resulted in some degree of instability. It has also been shown that encapsulating HPA in sol-gel silica matrices has produced an increase in catalytic performance without compromising the catalytic activity of the HPA. In this work, we analyzed the activity of a silica sol-gel supported HPA catalyst. The reaction which was chosen to illustrate such issues was the oxidation/dehydration of 1-butanol. In addition, the specific role of the support in the catalytic process is described. In this work, we characterized the silica-sol gel supported HPA catalyst to try to understand the effect of preparation in the overall catalytic selectivity and activity.