Inferior Outcomes on the Waiting List in Low-Volume Pediatric Heart Transplant Centers

Impact of ventricular assist device use on pediatric heart transplant waitlist mortality: Analysis of the scientific registry of transplant recipients database

BACKGROUND

Children awaiting heart transplant (Tx) have a high risk of death due to donor organ scarcity. Historically, ventricular assist devices (VADs) reduced waitlist mortality, prompting increased VAD use. We sought to determine whether the VAD survival benefit persists in the current era.

METHODS

Using the Scientific Registry of Transplant Recipients, we identified patients listed for Tx between 3/22/2016 and 9/1/2020. We compared characteristics of VAD and non-VAD groups at Tx listing. Cox proportional hazards models were used to identify risk factors for 1-year waitlist mortality.

RESULTS

Among 5054 patients, 764 (15%) had a VAD at Tx listing. The VAD group was older with more mechanical ventilation and renal impairment. Unadjusted waitlist mortality was similar between groups; the curves crossed ~90 days after listing (p = .55). In multivariable analysis, infant age (HR 2.77, 95%CI 2.13-3.60), Black race (HR 1.57, 95%CI 1.31-1.88), congenital heart disease (HR 1.23, 95%CI 1.04-1.46), renal impairment (HR 2.67, 95%CI 2.19-3.26), inotropes (HR 1.28, 95%CI 1.09-1.52), and mechanical ventilation (HR 2.23, 95%CI 1.84-2.70) were associated with 1-year waitlist mortality. VADs were not associated with mortality in the first 90 waitlist days but were protective for those waiting ≥90 days (HR 0.43, 95%CI 0.26-0.71).

CONCLUSIONS

In the current era, VADs reduce waitlist mortality, but only for those waitlisted ≥90 days. The differential effect by race, size, and VAD type is less clear. These findings suggest that Tx listing without VAD may be reasonable if a short waitlist time is anticipated, but VADs may benefit those expected to wait >90 days.

Later Brain Death Declaration Correlates to Favorable Donor Characteristics but Decreased Heart Acceptance

BACKGROUND

With rates of potential donor heart discard as high as 66% nationally, quality improvement efforts must seek to optimize donor utilization. Whether the timing of donor brain death declaration (BDD) influences organ acceptance is understudied. The authors sought to characterize the impacts of time between donor hospital admission and BDD on heart utilization and posttransplant outcomes.

METHODS

All potential heart donors and recipients in the United Network for Organ Sharing database were identified (2006-2021). Admission-to-BDD cohorts were: 1 to 2 d (n = 52 469), 3 to 4 d (n = 44 033), 5 to 7 d (n = 24 509), and 8 to 10 d (n = 8576). Donor clinical characteristics were compared between cohorts, and donor acceptance was assessed using multivariable binary logistic regression. Recipient posttransplant survival was assessed with the Kaplan-Meier method.

RESULTS

Donor demographics and comorbidity profiles (diabetes and hypertension) were comparable across cohorts. Anoxia/overdose deaths were more common (10% > 21% > 24% > 18%, respectively) and cardiopulmonary resuscitation requirements were higher (37% > 52% > 58% > 47%) when BDD occurred longer after admission. Renal dysfunction (44% > 44% > 35% > 29%) and inotrope requirements (52% > 25% > 36% > 29%) were lower in the later BDD cohorts. Proportions of hepatic dysfunction (18%-21%) and left ventricular ejection fraction <50% (13%-16%) were clinically equivalent. Donor acceptance differed by admission-to-BDD cohort (36% [1-2 d], 34% [3-4 d], 30% [5-7 d], and 28% [8-10 d]). Admission-to-BDD >4 d was independently associated with lower odds of acceptance on multivariable analysis (odds ratio 0.79, P  < 0.001). Recipients experienced equivalent posttransplant survival for all donor admission-to-BDD cohorts ( P  = 0.999 adults and P  = 0.260 pediatrics).

CONCLUSIONS

Heart donors with later BDD were disproportionately discarded despite similar-to-favorable overall clinical profiles, resulting in nearly 3000 fewer transplants during the study. Increased utilization of donors with later BDD and "high-risk" characteristics (eg, anoxia/overdose, cardiopulmonary resuscitation requirement) can improve rates of transplantation without compromising outcomes.

Survival does not differ by annual center transplant volume-A Pediatric Heart Transplant Society Registry study

BACKGROUND

There are conflicting data regarding the relationship between center volume and outcomes in pediatric heart transplantation. Previous studies have not fully accounted for differences in case mix, particularly in high-risk congenital heart disease (CHD) groups. We aimed to evaluate the relationship between center volume and outcomes using the Pediatric Heart Transplant Society (PHTS) Registry and explore how case mix may affect outcomes.

METHODS

A retrospective cohort study of all pediatric patients in the PHTS Registry who received a heart transplant from 2009 to 2018 was performed. Centers were divided into 5 groups based on average yearly transplant volume. The primary outcome was time to death or graft loss and outcomes were compared using Kaplan-Meier analysis.

RESULTS

There were 4583 cases among 55 centers included. There was no difference in time to death or graft loss by center volume in the entire cohort (p = .75), in patients with CHD (p = .79) or in patients with cardiomyopathy (p = .23). There was also no difference in time to death or graft loss by center size in patients undergoing transplant after Norwood, Glenn or Fontan (log rank p = .17, p = .31, and p = .10 respectively). There was a statistically significant difference in outcomes by center size in the positive crossmatch group (p < .0001), though no discernible pattern related to high or low center volume.

CONCLUSIONS

Outcomes are similar among transplant centers of all sizes, including for high-risk patient groups with CHD. Future work is needed to understand how patient-specific risk factors may vary among centers of various sizes and whether this influences patient outcomes.

Pediatric risk to orthotopic heart transplant (PRO) score: Insights from United Network for Organ Sharing (UNOS) waitlist mortality findings

BACKGROUND

Pediatric heart transplant candidates on the waitlist have the highest mortality rate among all solid organ transplants. A risk score incorporating a candidate's individual risk factors may better predict mortality on the waitlist and optimize organ allocation to the sickest of those awaiting transplant.

METHODS

Using the United Network for Organ Sharing (UNOS) database, we evaluated a total of 5542 patients aged 0-18 years old on the waitlist for a single, first time, heart transplant from January 2010 to June 2019. We performed a univariate analysis on two-thirds (N = 3705) of these patients to derive the factors most associated with waitlist mortality or delisting secondary to deterioration within 1 year. Those with a p <0.2 underwent a multivariate analysis and the resulting factors were used to build a prediction model using the Fine-Grey model analysis. This predictive scoring model was then validated on the remaining one-third of the patients (N = 1852).

RESULTS

The Pediatric Risk to OHT (PRO) scoring model utilizes the following unique patient variables: blood type, diagnosis of congenital heart disease, weight, presence of ventilator support, presence of inotropic support, extracorporeal membrane oxygenation (ecmo) status, creatinine level, and region. A higher score indicates an increased risk of mortality. The PRO score had a predictive strength of 0.762 as measured by area under the ROC curve at 1 year.

CONCLUSION

The PRO score is an improved predictive model with the potential to better assess mortality for patients awaiting heart transplant.

Heart transplant offers are less likely to be accepted on weekends, holidays, and conferences

BACKGROUND

The existence of a "weekend effect" in heart transplantation (HTx) is understudied. The present study sought to determine whether the odds of (HTx) offer acceptance differed for adult and pediatric candidates depending upon the day on which the offer occurred.

METHODS

United Network for Organ Sharing data were used to identify all HTx offers to adult (listing age ≥18) and pediatric candidates from 2000-2019. Odds of offer acceptance were studied, comparing weekends, holidays, and conferences (Society of Thoracic Surgeons [STS], American Association for Thoracic Surgery [AATS], International Society for Heart and Lung Transplantation [ISHLT]) to "baseline" (all other days). Multivariable binary logistic regression analyses were performed to determine independent predictors of offer nonacceptance, controlling for the impacts of program transplant volume, region, and candidate characteristics.

RESULTS

A total of 323,953 offers occurred - 298,405 to adults and 25,548 to pediatric candidates. Clinically significant differences did not exist in donor or candidate characteristics between baseline or other events. The number of offers per day was stable throughout the year for both adults (p = 0.191) and pediatrics (p = 0.976). In adults, independently lower odds of acceptance existed on weekends (OR 0.88 [95% CI 0.84-0.92]), conferences in aggregate (0.86 [0.77-0.95]), and holidays in aggregate (0.81 [0.72-0.91]). In children, independently lower odds of acceptance were seen on weekends (0.88 [0.79-0.98]), during STS (0.46 [0.25-0.83], and during Christmas (0.32 [0.14-0.76]).

CONCLUSIONS

The day on which a HTx offer occurs significantly impacts its likelihood of acceptance. Further work can determine the impacts of human behavior or resource distribution, but knowledge of this phenomenon can inform efforts to ensure ideal organ allocation throughout the year.

Trends in Survival for Pediatric Transplantation

OBJECTIVES

Progress in pediatric transplantation measured in the context of waitlist and posttransplant survival is well documented but falls short of providing a complete perspective for children and their families. An intent-to-treat analysis, in which we measure survival from listing to death regardless of whether a transplant is received, provides a more comprehensive perspective through which progress can be examined.

METHODS

Univariable and multivariable Cox regression was used to analyze factors impacting intent-to-treat survival in 12 984 children listed for heart transplant, 17 519 children listed for liver transplant, and 16 699 children listed for kidney transplant. The Kaplan-Meier method and log-rank test were used to assess change in waitlist, posttransplant, and intent-to-treat survival. Wait times and transplant rates were compared by using χ2 tests.

RESULTS

Intent-to-treat survival steadily improved from 1987 to 2017 in children listed for heart (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.96-0.97), liver (HR 0.95, 95% CI 0.94-0.97), and kidney (HR 0.97, 95% CI 0.95-0.99) transplant. Waitlist and posttransplant survival also improved steadily for all 3 organs. For heart transplant, the percentage of patients transplanted within 1 year significantly increased from 1987 to 2017 (60.8% vs 68.7%); however, no significant increase was observed in liver (68.9% vs 72.5%) or kidney (59.2% vs 62.7%) transplant.

CONCLUSIONS

Intent-to-treat survival, which is more representative of the patient perspective than individual metrics alone, steadily improved for heart, liver, and kidney transplant over the study period. Further efforts to maximize the donor pool, improve posttransplant outcomes, and optimize patient care while on the waitlist may contribute to future progress.

Interplay between donor and recipient factors impacts outcomes after pediatric heart transplantation: An analysis from the united network for organ sharing database

BACKGROUND

Donor utilization rates continue to be low for pHT, however, efforts to expand the donor acceptance criteria have shown mixed results in single-institution studies in pediatric and adult transplantation. Purpose of this study is to assess impact of individual and cumulative donor risk factors on transplant outcomes as well as the interplay between donor and recipient risk factors as it relates to transplant outcomes.

METHOD

We analyzed pHT UNOS data (2008-2018) to compare the recipient characteristics, donor characteristics, and outcomes based on donor ejection fraction of less than 50% (low EF) and or ischemic time of greater than 4 hours (prolonged IT).

RESULTS

A total of 4345 pHT were performed of which 1309 (30.1%) were with prolonged IT and 122 (2.8%) in low EF. Additionally, 58 (1.3%) were performed with both low EF and prolonged IT (combined risk). Rest (2856 patients, 65.7%) was considered low risk. Recipients of combined risk were more likely to be younger, have post-surgical congenital heart disease, be on ECMO or ventilator but less likely on VAD (all P < .01) compared with any other group. Waitlist time was significantly lower for low EF (mean 39 days, 15-109) or combined risk group (36 days, range 15-80) compared with other groups (60 days, range 23-125) (P = .01). 1-year mortality was 8% in low-risk group, 12% in prolonged IT, 14% in reduced EF, and 28% in combined risk patients (P < .01). Number of treated rejections in one year were significantly higher in prolonged IT and combined risk group compared to other groups (P < .01). When stratified by recipient risk, there was no difference in outcomes for low risk, prolonged IT, or low EF groups; however, there were significant survival differences for high-risk recipient versus low-risk recipient in each donor group.

CONCLUSION

Lower EF donors performed similar to prolonged IT donor, but were uncommonly used. Acceptance of risk was common in recipients deemed higher risk for waitlist mortality and led to shorter wait times. Caution should be used in accepting combined risk transplants. The recipient risk factors have significant impact on outcomes across all donor risk groups and further analysis will help balance the waitlist mortality with post-transplant outcomes.

A coordinated approach to improving pediatric heart transplant waitlist outcomes: A summary of the ACTION November 2019 waitlist outcomes committee meeting

The number of children needing heart transplantation continues to rise. Although improvements in heart failure therapy, particularly durable mechanical support, have reduced waitlist mortality, the number of children who die while waiting for a suitable donor organ remains unacceptably high. Roughly, 13% of children and 25% of infants on the heart transplant waitlist will not survive to transplantation. With this in mind, the Advanced Cardiac Therapies Improving Outcomes Collaborative Learning Network (ACTION), through its Waitlist Outcomes Committee, convened a 2-day symposium in Ann Arbor, Michigan, from 2-3 November 2019, to better understand the factors that contribute to pediatric heart transplant waitlist mortality and to focus future efforts on improving the organ allocation rates for children needing heart transplantation. Using improvement science methodology, the heart failure-transplant trajectory was broken down into six key steps, after which modes of failure and opportunities for improvement at each step were discussed. As a result, several projects aimed at reducing waitlist mortality were initiated.

A comprehensive strategy in donor acceptance: Impact on pediatric waitlist and heart transplant outcomes

Significant inter- and intra-center practice variability is present in pediatric donor heart acceptability. This may contribute to variation in the donor refusal rate and may impact waitlist time, morbidity, mortality, and transplant rates. In order to reduce practice variability, our center developed and implemented a comprehensive strategy regarding donor acceptance in September 2017. The aim of this study was to assess the impact of this strategy on waitlist time and outcomes as well as early post-transplant outcomes. We performed a single-center, retrospective analysis of all pediatric (<18 years) patients listed for single-organ heart transplant at our center from September 2015 to September 2018. Patients were divided into those listed before (Group 1) and after implementation of the comprehensive strategy (Group 2). The primary end-point was waitlist time. Secondary end-points included waitlist removal due to death or clinical deterioration, donor refusals per listed patient, early post-transplant outcomes (graft failure, mechanical ventilation time, inotropic support, length of hospital stay) and 1-year post-transplant survival. Of 78 listed patients, 54 were transplanted (29 in Group 1), 9 were removed due to death or clinical deterioration (7 in Group 1) and 15 were removed due to clinical improvement (12 in Group 1). The waitlist time was significantly shorter in Group 2 (17 days, IQR 7-53) vs Group 1 (90 days, IQR 14-162); P = .006. The number of donor refusals was lower in Group 2 (1, IQR 0-2.2) vs Group 1 (4, IQR 2-19); P < .001. The percentage of refused donors with normal function (Left ventricular ejection fraction > 50%) was lower in Group 2 vs Group 1 (53% vs 84%; P < .001). Difference in removal from the waitlist for death or deterioration in Group 2 vs Group 1 (n = 2, 7% vs n = 7, 20%, P = .18) did not reach statistical significance. There was no difference in post-transplant outcomes between groups. The waitlist time and donor refusals significantly decreased after implementation of a comprehensive donor acceptance strategy without impacting transplant outcomes. This analysis supports the need for a comprehensive approach to donor organ acceptance within a pediatric transplant center.

Most pediatric transplant centers are low volume, adult-focused, and in proximity to higher volume pediatric centers

BACKGROUND

Independent studies provide evidence that low volume pediatric solid organ transplant centers have inferior outcomes compared to high volume pediatric centers. The study assessed whether patients treated at low volume pediatric centers have access to higher volume pediatric centers, which offer potentially better outcomes.

METHODS

We analyzed center specific data on 467 pediatric solid organ transplant centers in the U.S using the Organ Procurement and Transplantation Network database from 2002 to 2014. The proximities of low volume pediatric centers to high volume pediatric centers were determined using Maptive, a tool based on Google Maps.

RESULTS

Most low volume pediatric transplant centers focused on transplantation of adults (84% heart, 83% liver, and 93% kidney programs). A majority of low volume pediatric centers (77% for heart, 53% for lung, 68% for liver and 90% for kidney) were within 150 miles of high volume centers. Among all children listed for transplantation, 30.7% were listed in low volume pediatric centers. Most low volume pediatric centers are adult focused and near high volume pediatric centers.

CONCLUSION

We need greater scrutiny of outcomes, particularly waitlist outcomes, of low volume pediatric solid organ transplant centers located close to high volume pediatric solid organ transplant centers.

TYPE OF STUDY AND LEVEL OF EVIDENCE

Retrospective Comparative Study, Level III.

Pediatric cardiac waitlist mortality-Still too high

Cardiac transplantation for children with end-stage cardiac disease with no other medical or surgical options is now standard. The number of children in need of cardiac transplant continues to exceed the number of donors considered "acceptable." Therefore, there is an urgent need to understand which recipients are in greatest need of transplant before becoming "too ill" and which "marginal" donors are acceptable in order to reduce waitlist mortality. This article reviewed primarily pediatric studies reported over the last 15 years on waitlist mortality around the world for the various subgroups of children awaiting heart transplant and discusses strategies to try to reduce the cardiac waitlist mortality.

Behavioral economics-A framework for donor organ decision-making in pediatric heart transplantation

The high discard rate of pediatric donor hearts presents a major challenge for children awaiting heart transplantation. Recent literature identifies several factors that contribute to the disparities in pediatric donor heart usage, including regulatory oversight, the absence of guidelines on pediatric donor heart acceptance, and variation among transplant programs. However, a likely additional contributor to this issue are the behavioral factors influencing transplant team decisions in donor offer scenarios, a topic that has not yet been studied in detail. Behavioral economics and decision psychology provide an excellent foundation for investigating decision-making in the pediatric transplant setting, offering key insights into the behavior of transplant professionals. We conducted a systematic review of published literature in pediatric heart transplant related to behavioral economics and the psychology of decision-making. In this review, we draw on paradigms from these two domains in order to examine how existing aspects of the transplant environment, including regulatory oversight, programmatic variation, and allocation systems, may precipitate potential biases surrounding donor offer decisions. Recognizing how human decision behavior influences donor acceptance is a first step toward improving utilization of potentially viable pediatric donor hearts.

Rehospitalization Following Pediatric Heart Transplantation: Incidence, Indications, and Risk Factors

Rehospitalization following pediatric heart transplantation is common. However, existing data remain somewhat limited. Using a novel linkage between administrative and clinical databases, pediatric heart transplant (HT) recipients from 29 centers who survived to discharge were retrospectively reviewed to determine the frequency, timing of, and indication for all-cause rehospitalizations in the year following transplant discharge. Of 2870 pediatric HT recipients, 1835 (63.9%) were rehospitalized in the first year post-discharge (5429 total readmissions). Rehospitalization rates varied significantly across centers (46% to 100%) and were inversely correlated to center transplant volume (r² 0.25, p < 0.01). The median number of rehospitalizations per patient was 2 (IQR 1-4) and the median time to first rehospitalization was 29 days (IQR 9-99 days). Independent risk factors for rehospitalization included younger age at HT (HR 0.99, 95% CI 0.97-0.99), congenital heart disease (HR 1.2, 95% CI 1.1-1.4), listing status 1B at transplant (HR 1.3, 95% CI 1.1-1.5), and post-transplant complications including rejection prior to discharge (HR 1.5 95% CI 1.3-1.8) and chylothorax (HR 1.3, 95% CI 1.0-1.6). Cardiac diagnoses were the most common indication for rehospitalization (n = 1600, 29.5%), followed by infection (n = 1367, 25.2%). These findings may serve to guide the development of interventions aimed at reducing post-HT hospitalizations.

ISHLT consensus statement on donor organ acceptability and management in pediatric heart transplantation

The number of potential pediatric heart transplant recipients continues to exceed the number of donors, and consequently the waitlist mortality remains significant. Despite this, around 40% of all donated organs are not used and are discarded. This document (62 authors from 53 institutions in 17 countries) evaluates factors responsible for discarding donor hearts and makes recommendations regarding donor heart acceptance. The aim of this statement is to ensure that no usable donor heart is discarded, waitlist mortality is reduced, and post-transplant survival is not adversely impacted.

Failure to rescue in the era of the lung allocation score: The impact of center volume

BACKGROUND

Failure to Rescue (FTR) is a valuable surgical quality improvement metric. The aim of this study is to assess the relationship between center volume and FTR following lung transplantation.

METHODS

Using the database of the United Network for Organ Sharing (UNOS) all adult, primary, isolated lung recipients in the United States between May 2005 and March 2016 were identified. FTR was defined as operative mortality after any of five specific complications. FTR was compared across terciles of transplantation centers stratified based on operative volume.

RESULTS

17,185 lung recipients met study criteria. The composite FTR rate (Death following at least one complication) was 20.7%. Following stratification by volume, FTR rates increased from high to middle tercile centers (19.3% vs. 23.0%). Multivariate logistic regression models suggested an independent relationship between higher center volume and lower FTR rates (p < 0.001).

CONCLUSION

Higher volume lung transplantation centers have lower rates of failure to rescue.

Revisiting the International Normalized Ratio Threshold for Bleeding Risk and Mortality in Primary Total Hip Arthroplasty: A National Surgical Quality Improvement Program Analysis of 17,567 Patients

BACKGROUND

Efforts to identify preoperative risk factors for primary total hip arthroplasty have amplified with its increasing incidence. The international normalized ratio (INR) is 1 measure that may influence postoperative outcomes. This study of a national database assessed whether there exists an association between preoperative INR and postoperative bleeding and mortality among patients who underwent primary total hip arthroplasty.

METHODS

We retrospectively analyzed 17,567 adult patients who underwent primary total hip arthroplasty in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) between 2005 and 2016. Patients were stratified by preoperative INR into 4 groups: INR <1.0, 1.0 to <1.25, 1.25 to <1.5, and ≥1.5. Bleeding necessitating transfusion was the primary outcome, and secondary outcomes included mortality, infection, and readmission. Multivariable logistic regressions controlled for baseline differences.

RESULTS

Among the patients who underwent total hip arthroplasty, 20.5% had INR <1.0, 73.6% had INR 1.0 to <1.25, 4.2% had INR 1.25 to <1.5, and 1.8% had INR ≥1.5. Mortality increased incrementally from 0.3% for INR <1.0 to 4.9% for INR ≥1.5 (p < 0.001), and bleeding risk increased from 13.2% for INR <1.0 to 29.3% for INR ≥1.5 (p < 0.001). After adjustment, bleeding risk was increased for INR 1.25 to <1.5 (odds ratio [OR], 1.55 [95% confidence interval (CI), 1.26 to 1.92]) and INR ≥1.5 (OR, 1.55 [95% CI, 1.15 to 2.08]) compared with INR <1.0. The only group associated with increased mortality was INR ≥1.5 (OR, 2.69 [95% CI, 1.07 to 6.76]). The length of stay significantly increased with increasing INR, from 3.6 to 6.3 days (p < 0.001).

CONCLUSIONS

This study found a significant, independent effect between increased preoperative INR and increased bleeding and mortality. Bleeding risk becomes evident at INR ≥1.25, and those patients with INR ≥1.5 are at significantly increased risk of mortality.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Ethical issues in access, listing and regulation of pediatric heart transplantation

Organ scarcity often drives ethical discussion in pediatric heart transplantation. There are questions about autonomy and equity in the referral patterns. There are questions about beneficence in how referral centers are established and operate. There are questions about fairness in how patients are listed and evaluated for listing exceptions. Finally, there are questions about beneficence, maleficence, and justice when it comes to the regulatory oversight of transplantation. This review will serve as a brief review of some of the more pressing ethical matters in pediatric heart transplantation and, where possible, offer potential solutions.

Criteria for Critical Care Infants and Children: PICU Admission, Discharge, and Triage Practice Statement and Levels of Care Guidance

OBJECTIVES

To update the American Academy of Pediatrics and Society of Critical Care Medicine's 2004 Guidelines and levels of care for PICU.

DESIGN

A task force was appointed by the American College of Critical Care Medicine to follow a standardized and systematic review of the literature using an evidence-based approach. The 2004 Admission, Discharge and Triage Guidelines served as the starting point, and searches in Medline (Ovid), Embase (Ovid), and PubMed resulted in 329 articles published from 2004 to 2016. Only 21 pediatric studies evaluating outcomes related to pediatric level of care, specialized PICU, patient volume, or personnel. Of these, 13 studies were large retrospective registry data analyses, six small single-center studies, and two multicenter survey analyses. Limited high-quality evidence was found, and therefore, a modified Delphi process was used. Liaisons from the American Academy of Pediatrics were included in the panel representing critical care, surgical, and hospital medicine expertise for the development of this practice guidance. The title was amended to "practice statement" and "guidance" because Grading of Recommendations, Assessment, Development, and Evaluation methodology was not possible in this administrative work and to align with requirements put forth by the American Academy of Pediatrics.

METHODS

The panel consisted of two groups: a voting group and a writing group. The panel used an iterative collaborative approach to formulate statements on the basis of the literature review and common practice of the pediatric critical care bedside experts and administrators on the task force. Statements were then formulated and presented via an online anonymous voting tool to a voting group using a three-cycle interactive forecasting Delphi method. With each cycle of voting, statements were refined on the basis of votes received and on comments. Voting was conducted between the months of January 2017 and March 2017. The consensus was deemed achieved once 80% or higher scores from the voting group were recorded on any given statement or where there was consensus upon review of comments provided by voters. The Voting Panel was required to vote in all three forecasting events for the final evaluation of the data and inclusion in this work. The writing panel developed admission recommendations by level of care on the basis of voting results.

RESULTS

The panel voted on 30 statements, five of which were multicomponent statements addressing characteristics specific to PICU level of care including team structure, technology, education and training, academic pursuits, and indications for transfer to tertiary or quaternary PICU. Of the remaining 25 statements, 17 reached consensus cutoff score. Following a review of the Delphi results and consensus, the recommendations were written.

CONCLUSIONS

This practice statement and level of care guidance manuscript addresses important specifications for each PICU level of care, including the team structure and resources, technology and equipment, education and training, quality metrics, admission and discharge criteria, and indications for transfer to a higher level of care. The sparse high-quality evidence led the panel to use a modified Delphi process to seek expert opinion to develop consensus-based recommendations where gaps in the evidence exist. Despite this limitation, the members of the Task Force believe that these recommendations will provide guidance to practitioners in making informed decisions regarding pediatric admission or transfer to the appropriate level of care to achieve best outcomes.

Impact and predictors of positive response to desensitization in pediatric heart transplant candidates

BACKGROUND

Desensitization, the process of reducing anti-human leukocyte antigen (HLA) antibodies in sensitized patients awaiting heart transplantation (HT), has unclear efficacy in pediatric HT candidates.

METHODS

Pediatric HT candidates listed at our institution between January 1, 2013 and June 30, 2018 were retrospectively evaluated. Sensitization was defined as the calculated panel reactive antibody (cPRA) ≥ 10% with ≥ 1 a strong positive antibody. The desensitization response was defined as a ≥ 25% reduction in the mean fluorescence intensity (MFI) for ≥ 90% of the strong positive antibodies on follow-up panel reactive antibody (PRA) testing before waitlist removal, HT, or death (data available for 13 patients).

RESULTS

The HT candidates were categorized as sensitized receiving desensitization therapy (ST, n = 14), sensitized not receiving therapy (SNT, n = 18), or non-sensitized (n = 55). A desensitization response was observed in 8 (62%) of the ST upon repeat PRA testing, with the ST responders receiving more doses of intravenous immunoglobulin (IVIG) (8 vs 2, p < 0.05). The anti-HLA class I antibodies were particularly resistant for non-responders (p = 1.9 × 10^-4). The combination of homograft and ventricular assist device was more sensitizing than either alone (p = 3.1 × 10^-4). However, these sensitization risk factors did not impact the desensitization response. The ST was associated with a higher likelihood of remaining listed and a longer waitlist time without substantially impacting the HT rate, waitlist mortality, or early post-HT outcomes.

CONCLUSIONS

Most ST patients had a favorable response to desensitization, with a dose-dependent response observed for IVIG. The anti-HLA class likely impacts the ST response, whereas traditional sensitization risk factors had no impact on the response.

Variability in donor selection among pediatric heart transplant providers: Results from an international survey

There is considerable variability in donor acceptance practices among adult heart transplant providers; however, pediatric data are lacking. The aim of this study was to assess donor acceptance practices among pediatric heart transplant professionals. The authors generated a survey to investigate clinicians' donor acceptance practices. This survey was distributed to all members of the ISHLT Pediatric Council in April 2018. A total of 130 providers responded from 17 different countries. There was a wide range of acceptable criteria for potential donors. These included optimal donor-to-recipient weight ratio (lower limit: 50%-150%, upper limit: 120%-350%), maximum donor age (25-75 years), and minimum acceptable left ventricular EF (30%-60%). Non-US centers demonstrated less restrictive donor selection criteria and were willing to accept older donors (50 vs 35 years, P < 0.001), greater size discrepancy (upper limit weight ratio 250% vs 200%, P = 0.009), and donors with a lower EF (45% vs 50%, P < 0.001). Recipient factors were most influential in the decision to accept marginal donors including recipients requiring ECMO support, ventilator support, and highly sensitized patients with a negative XM. However, programmatic factors impacted the decision to decline marginal donors including recent programmatic mortalities and concerns for programmatic restrictions from regulatory bodies. There is significant variation in donor acceptance practices among pediatric heart transplant professionals. Standardization of donor acceptance practices through the development of a consensus statement may help to improve donor utilization and reduce waitlist mortality.

Age-Dependent Impact of Pre-Transplant Intensive Care Unit Stay on Mortality in Heart Transplant Recipients

Background

Heart transplantation (HTx) is a treatment option for refractory end-stage heart failure. Severe illness requiring pre-transplant intensive care unit (ICU) stay may be a risk factor for diminished post-transplant survival, but this association is surprisingly inconsistent in recent studies. To clarify the significance of ICU stay as a risk factor for heart transplant outcomes, we aimed to define if patient age was a factor in which ICU stay was predictive of survival after HTx.

Methods

De-identified data were obtained on isolated first-time HTx performed during the years 2006 - 2015 from the UNOS Registry. Nine age groups were defined. The primary outcome was 1-year post-transplant mortality. Cox proportional hazard regression estimated unadjusted and adjusted hazard ratio (HR) associated with pre-transplant ICU stay in each age group.

Results

The analysis included 19,508 patients (9% deceased within 1 year). In the overall cohort, pre-transplant ICU stay was associated with increased hazard of 1-year mortality (HR = 1.3; 95% confidence interval (CI): 1.2 - 1.4; P < 0.001); but further univariate analysis showed a greater hazard of 1-year mortality associated with ICU stay in infants (HR = 2.2; 95% CI: 1.5 - 3.2; P < 0.001). However, the adjusted analysis found that adults ages 40 - 49 had the highest statistically significant hazard of 1-year mortality (HR = 1.5; 95% CI: 1.1 - 2.1; P = 0.011).

Conclusions

Our study established age variation in the association between ICU stay and survival after HTx, with this association being strongest among adults, 40 to 49 years of age, undergoing HTx. Previous data suggesting decreased survival in infants may be related to the increased use of extracorporeal membrane oxygenation as a mechanical cardiac assist rather than ventricular assist devices.

Health outcomes and the healthcare and societal cost of optimizing pediatric surgical care in the United States

BACKGROUND

There is a movement to ensure that pediatric patients are treated in appropriately resourced hospitals through the ACS Children's Surgery Verification (CSV) program. The objective of this study was to assess the potential difference in care provision, health outcomes and healthcare and societal costs after implementation of the CSV program.

METHODS

All 2011 inpatient admissions for selected complex pediatric patients warranting treatment at a hospital with Level I resources were evaluated across 6 states. Multivariate regressions were used to analyze differences in healthcare outcomes (postoperative complications including death, length of stay, readmissions and ED visits within 30 days) and costs by CSV level. Recycled predictions were used to estimate differences between the base case scenario, where children actually received care, and the optimized scenario, where all children were theoretically treated at Level I centers.

RESULTS

8,006 children (mean age 3.06 years, SD 4.49) met inclusion criteria, with 45% treated at Level I hospitals, 30% at Level II and 25% at Level III. No statistically significant differences were observed in healthcare outcomes. Readmissions within 30 days were higher at Level II compared to Level I centers (adjusted IRR 1.61; 95% CI 1.11, 2.34), with an estimated 24 avoidable readmissions per 1000 children if treatment were shifted from Level II to Level I centers. Overall, costs per child were not significantly different between the base case and the optimized scenario.

CONCLUSION

Many complex surgical procedures are being performed at Level II/III centers. This study found no statistically significant increase in healthcare or societal costs if these were performed instead at Level I centers under the optimized scenario. Ongoing evaluation of efforts to match institutional resources with individual patient needs is needed to optimize children's surgical care in the United States.

LEVEL OF EVIDENCE

II.

Pediatric heart transplantation at adult-specialty centers in the United States: A multicenter registry analysis

Recent Organ Procurement and Transplantation Network bylaw revisions mandate that US transplant programs have an "approved pediatric component" in order to perform heart transplantation (HT) in patients <18 years old. The impact of this change on adolescents, a group known to be at high risk for graft loss and nonadherence, is unknown. We studied all US primary pediatric (age <18 years) HT from 2000 to 2015 to compare graft survival between centers organized mainly for adult versus pediatric care. Centers were designated as pediatric- or adult-specialty care according to the ratio of pediatric:adult HT performed and minimum age of HT (pediatric-specialty defined as ratio>0.7; adult-specialty ratio<0.05 and minimum age >8 years). In propensity score-matched cohorts, we observed no difference in graft loss by center type (median survival: adult 12.4 years vs pediatric 9.2 years, P = .174). Compared to the matched pediatric cohort, adult-specialty center recipients lived closer to their transplant center (31 vs 45 miles, P = .012), and trended toward fewer out-of-state transplants (15 vs 25%, P = .082). Our data suggest that select adolescents can achieve similar midterm graft survival at centers organized primarily for adult HT care. Regardless of post-HT setting, the development of care models that demonstrably improve adherence may be of greatest benefit to improving survival of this high-risk population.

Program-specific transplant rate ratios: Association with allocation priority at listing and posttransplant outcomes

The Scientific Registry of Transplant Recipients (SRTR) is considering more prominent reporting of program-specific adjusted transplant rate ratios (TRRs). To enable more useful reporting of TRRs, SRTR updated the transplant rate models to adjust explicitly for components of allocation priority. We evaluated potential associations between TRRs and components of allocation priority that could indicate programs' ability to manipulate TRRs by denying or delaying access to low-priority candidates. Despite a strong association with unadjusted TRRs, we found no candidate-level association between the components of allocation priority and adjusted TRRs. We found a strong program-level association between median laboratory Model for End-stage Liver Disease (MELD) score at listing and program-specific adjusted TRRs (r = .37; P < .001). The program-level association was likely confounded by regional differences in donor supply/demand and listing practices. In kidney transplantation, higher program-specific adjusted TRRs were weakly associated with better adjusted posttransplant outcomes (r = -.14; P = .035) and lower adjusted waitlist mortality rate ratios (r = -.15; P = .022), but these associations were absent in liver, lung, and heart transplantation. Program-specific adjusted TRRs were unlikely to be improved by listing candidates with high allocation priority and can provide useful information for transplant candidates and programs.

Resource utilization at the time of prostacyclin initiation in children in pulmonary arterial hypertension: a multicenter analysis

There are limited data investigating the epidemiology and resource utilization associated with parenteral prostacyclin use in children. We sought to examine national trends in treatment practices and resource utilization during prostacyclin initiation for pulmonary arterial hypertension (PAH) at children’s hospitals in the United States. Patients with PAH initiated on parenteral epoprostenol and treprostinil (2004–2014) were identified using a nationwide administrative database. Demographics, clinical characteristics, and resource utilization were compared between epoprostenol and treprostinil groups. Costs were indexed in 2014 US dollars. Among 1448 children admitted with a primary or secondary diagnosis of PAH, 280 (19%) were initiated on parenteral prostacyclins (epoprostenol n = 195 and treprostinil n = 85). Epoprostenol predominated early (97% of initiations in 2005); however, treprostinil predominated recently (52–67% of initiations/year). Children initiated on treprostinil had shorter ICU stays (1 [IQR = 0–4] vs. 4 [0–10] days, P < 0.001), shorter total lengths of stay (4 [2–9] vs. 8 [4–18] days, P = 0.001), and lower in-hospital mortality (1 vs. 12%, P = 0.001) with no difference in 30-day (13 vs. 19%, P = 0.19) or one-year readmission rates (56 vs. 61%, P = 0.41). Inpatient costs were lower for treprostinil initiation ($23,779 [11,830–39,535] vs. $32,976 [11,904–94,082], P = 0.03), with a greater difference in the recent era (2009–2013). Though significant variation exists regarding prostacyclin use for PAH across US centers, prostacyclins are common among children with PAH. Treprostinil initiation has been increasing and is associated with less resource utilization and lower cost compared to epoprostenol initiation. Post-discharge outcome data are needed to fully inform decision-making about the relative benefits of parental prostacyclin drug choice.