Status of Pediatric Perfusion Education: 2000 Survey

In recent years, studies have raised questions about pediatric perfusion training, minimum proficiency requirements, and specialization. To understand these questions better, a survey was undertaken to investigate the status of pediatric/ neonatal perfusion training in the United States. Three groups were surveyed: program directors (PD), recent graduates of perfusion programs (RG), and pediatric cardiac anesthesiologists (PCA). Program directors and recent graduates were queried about didactic curriculum and clinical experiences. All three groups were asked core questions regarding minimum proficiency, specialization, and need for a postgraduate style program. Didactically, 65% of program directors believed that perfusion programs provided a solid introductory knowledge base in infant perfusion. Clinically, students performed an average of 124 ± 42.5 adult and 17 ± 12.9 pediatric cases during their education. Program directors cited numerous limitations to clinical pediatric education, including access to pediatric cases and allocation of resources. The PD (69%) and RG (96%) both believed graduates were less prepared to perform infant/pediatric cardiopulmonary bypass (CPB) at graduation as compared to adult CPB. The opinions of all three groups were divided when asked whether the essentials and guidelines requirement for minimum pediatric caseload is too low (yes response: PD 52%, RG 73%, PCA 47%). The PD and RG were against pediatric subspecialization/certification (87%, 57% respectively); whereas, the PCA were unanimously in favor (100%) of pediatric subspecialization/ certification for perfusionist. All three groups felt a postgraduate-style program in infant perfusion would benefit the community (78%, 82%, 100%). Finally, 64% of RG said that, if available, they would have considered entering a training program in pediatric/neonatal perfusion after graduation. Our results indicate that there are still limitations to pediatric perfusion education. A postgraduate-style program in infant perfusion is one possible solution to this problem

Cell Saver Blood Reinfusion Up to 24 Hours Post Collection in Pediatric Cardiac Surgical Patients Does Not Increase Incidence of Hospital-Acquired Infections or Mortality

Cell saver blood reinfusion, a blood conservation technique recently available for pediatric use, is typically limited to 6 hours post processing to guard against bacterial contamination. We hypothesize that reinfusion of cell saver blood up to 24 hours post collection in children after cardiac surgery will not increase the incidence of hospital-acquired infections (HAI). The primary aim is to compare incidence of HAI between children receiving cell saver blood ≤6 hours vs. >6 to ≤24 hours from its collection. The secondary aim is to compare mortality and clinical outcomes. Retrospective chart review of children ≤18 years undergoing cardiac surgery with cardiopulmonary bypass (CPB) from 2013 to 2018 when cell saver collection and bedside temperature controlled storage became standard of care. Patients on extracorporeal membrane oxygenation (ECMO) within 48 hours postoperatively and those who did not receive cell saver were excluded. The primary outcome was HAI incidence postoperative days 0–6. Demographic data included diagnosis, surgical severity score, and clinical outcomes. 466 patients, 45% female. No significant between-group differences identified. There was no significant difference in HAI (control 8.5% vs. treatment 8.0%, p = .80) and death (control 7.9% vs. treatment 4.9%, p = .20). Noninferiority testing indicated the treatment group was not statistically inferior to the control group (p = .0028). Kaplan–Meier curve depicted similar status between-group rates of no infection or death; 92% treatment vs. 91% control. Total volume allogeneic red blood cell transfusion (allogeneic blood transfusion [ABT]) up to 24 hours postoperatively was significantly less in the treatment group, p 6 to ≤24 hours post collection. Treatment subjects received significantly less volume of ABT. Considering the risks of ABT, these findings support cell saver blood reinfusion up to 24 hours post collection

Mitochondrial ATP Synthase Tetramer Disassembly following Blood-Based or del Nido Cardioplegia during Neonatal Cardiac Surgery

Conservation of mitochondrial adenosine triphosphate (ATP) synthase proteins during ischemia is critical to preserve ATP supply and ventricular function. Following myocardial ischemia in adults, higher order ATP synthase tetramer proteins disassemble into simpler monomer units, reducing the efficiency of ATP production. However, it is unknown if myocardial ischemia following the use of cardioplegia results in tetramer disassembly in neonates, and whether it can be mitigated by cardioplegia if it does occur. We investigated myocardial ATP synthase tetramer disassembly in both a neonatal lamb cardiac surgery model and in neonatal children requiring cardiac surgery for the repair of congenital heart disease. Neonatal lambs (Ovis aries) were placed on cardiopulmonary bypass (CPB) and underwent cardioplegic arrest using a single dose of 30 mL/kg antegrade blood-based potassium cardioplegia (n = 4) or a single dose of 30 mL/kg antegrade del Nido cardioplegia (n = 6). Right ventricular biopsies were taken at baseline on CPB (n = 10) and after approximately 60 minutes of cardioplegic arrest before the cross clamp was released (n = 10). Human right ventricular biopsies (n = 3) were taken following 40.0 ± 23.1 minutes of ischemia after a single dose of antegrade blood-based cardioplegia. Protein complexes were separated on clear native gels and the tetramer to monomer ratio quantified. From the neonatal lamb model regardless of the cardioplegia strategy, the tetramer:monomer ratio decreased significantly during ischemia from baseline measurements (.6 ± .2 vs. .5 ± .1; p = .03). The del Nido solution better preserved the tetramer:monomer ratio when compared to the blood-based cardioplegia (Blood .4 ± .1 vs. del Nido .5 ± .1; p = .05). The tetramer:monomer ratio following the use of blood-based cardioplegia in humans aligned with the lamb data (tetramer:monomer .5 ± .2). These initial results suggest that despite cardioprotection, ischemia during neonatal cardiac surgery results in tetramer disassembly which may be limited when using the del Nido solution

In Vitro and In Vivo Comparison of Hemoglobin and Electrolytes Following the Collection of Cell Saver Blood Washed with Either Normal Saline or Plasma-Lyte A

Cell saver blood is typically washed with normal saline (NS); however, recent studies have reported decreased red blood cell hemolysis and increased platelet function when a more physiologic washing solution, such as Plasma-Lyte A (PL-A) is used. We evaluated the in vitro and in vivo effects of NS compared to PL-A as washing solutions for cell saver blood in pediatric cardiac surgery. Cell saver blood was re-infused for up to 24 hours post-collection. Laboratory and clinical data were collected from infants receiving cell saver washed with either NS (n = 20) or PL-A (n = 21). Compositions of the cell saver blood were compared between groups at 5 in vitro time points and in vivo patient blood at 24 hours post-bypass. Although there were differences in in vitro laboratory values between groups; 24 hours post-bypass, in vivo results were similar. Our data supports 24-hour reinfusion of cell saver washed with either NS versus PL-A in pediatric cardiac surgery patients, and provides data on the differences in cell saver composition to guide future studies

Modification of a Biventricular Assist Device to Facilitate Preservative Infusion and Organ Recovery in a Nonheart-Beating Donor

A 46-year-old patient supported by a biventricular assist device (BiVAD) was transferred to our institution for evaluation for heart transplant. The patient was found to have a large intracranial hemorrhage with profound deterioration of neurologic status. The poor prognosis prompted the decision to withdraw care and pursue organ donation. Because the patient did not meet brain death criteria, nonheart-beating donor organ donation was pursued. After the termination of care, the BiVAD was modified: the left side to provide organ preservative solution and the right side to allow drainage. Eight liters of cold University of Wisconsin solution were pumped systemically over 10 minutes, the donor was drained, and the liver was harvested. This technique expedited donor perfusion by eliminating the need to cannulate, minimizing ischemic time for the liver. Although the recipient outcome was poor, and retransplantation was eventually necessary, we believe it was most likely not attributable to the quality of organ preservation. This report discusses the technical aspects of this potentially beneficial procedure