Children with single-ventricle physiology do not benefit from higher hemoglobin levels post cavopulmonary connection: results of a prospective, randomized, controlled trial of a restrictive versus liberal red-cell transfusion strategy

A survey on perioperative red blood cell transfusion trigger strategies for pediatric patients in the Nordic countries

BACKGROUND

Transfusion of red blood cells (RBC) to rapidly increase hemoglobin levels have been associated with increased risks and worse outcomes in critically ill children. The international TAXI consensus from 2018 (pediatric critical care transfusion and anemia expertise initiative) recommended restrictive RBC transfusion strategies in pediatric patients.

OBJECTIVE

To elucidate physicians perioperative RBC transfusion trigger strategies for pediatric patients in the Nordic countries and to investigate what factors influence the decision to transfuse this group of patients.

METHODS

An electronic web-based survey designed by the TransfUsion triggers in Pediatric perioperAtive Care (TUPAC) initiative including six different clinical scenarios was sent to anesthesiologist treating pediatric patients at university hospitals in the Nordic countries on February 1, 2023 and closed May 1, 2023.

RESULTS

The study had a response rate of 67.7% (180 responders out of 266 contacted). Median hemoglobin thresholds triggering RBC transfusions were 7.0 [IQR, 7.0-7.3] g/dL in a stable young child (1-year-old), 7.0 [IQR, 7.0-7.0] g/dL in the stable older child (5-year-old), 8.5 [IQR, 8.0-9.0] g/dL in the older child with cardiac disease, 9.0 [IQR, 8.0-10.0] g/dL the older child with traumatic brain injury, 8.0 [IQR, 7.3-9.0] g/dL in stabilized older child with septic shock and 8.0 [IQR, 7.0-9.0] g/dL in the older child with active but non-life-threatening bleeding. Apart from specific hemoglobin level, RBC transfusions were mostly triggered by high lactate level (74.2%), increasing heart rate (68.0%), prolonged capillary refill time (48.3%), and lowered blood pressure (47.8%). No statistical difference was found between the Nordic countries, work experience, or enrollment in a pediatric anesthesia fellowship program regarding RBC transfusion strategies.

CONCLUSIONS

Anesthesiologists in the Nordic countries report restrictive perioperative RBC transfusion strategies for children that are mostly in agreement with the international TAXI recommendations. However, RBC transfusions strategies were modified to be guided by more liberal trigger levels when pediatric patients presented with severe comorbidity such as severe sepsis, septic shock, and non-life-threatening bleeding.

Reducing Adverse Events Associated with Pediatric Cardiac Catheterization: A Quality Improvement Project Focusing on Decreasing Catheterization-Associated Blood Transfusions

The objective of this study is to describe interventions and outcomes of a quality improvement (QI) project to reduce red blood cell transfusion (RBCT) within 72 h of pediatric cardiac catheterization. Using Plan-Do-Study-Act (PDSA) methodology, we applied interventions including (1). Intraprocedural-to reduce hemodilution, blood loss, and excessive anticoagulation, (2). Standardization of institutional transfusion criteria, and (3). "Hard stop" requiring QI team consultation prior to elective post-catheterization RBCT. Primary outcome measures were frequency of RBCT from IMPACT quarterly reports and cases between transfusions (CBT). Length of stay (LOS) was the primary countermeasure. Characteristics of patients who did and did not receive RBCT were compared. 698 pediatric cardiac catheterizations occurred between 4/2017 and 8/2023. Intraprocedural interventions did not alter frequency of RBCT or CBT. Standardized transfusion guidelines followed by the "hard stop" decreased RBCT frequency from 10 to 1.9% and increased CBT without increasing LOS. Patients requiring RBCT were younger (medians 0.31 vs 2.4 years), smaller (5.2 vs 11.8 kg), and had longer procedures (2.24 vs 1.57 h) all p < 0.001. Single ventricle patients were more likely to have RBCT than simple biventricular patients (14.1% vs 3.1%; RR = 4.57, 95% CI 2.29-10.4; p < 0.001). Procedure type (diagnostic vs. intervention) and starting hemoglobin concentration were comparable between groups. Programmatic adherence to standardized peri-procedural transfusion guidelines successfully decreased RBCT without compromising patient care or increasing LOS. Younger age, lower weight, procedure length, and single ventricle physiology were all associated with RBCT risk.

Safety of bloodless open-heart surgery on cardiopulmonary bypass in selected children: A single center experience with minimal invasive extracorporeal circulation

INTRODUCTION

Bloodless cardiac surgery refers to open-heart surgery without blood or blood products. The cardiopulmonary bypass (CPB) circuits are primed with crystalloid solely, and there is no intraoperative blood transfusion.

METHODS

Our program considers bloodless congenital cardiac surgery with a minimal invasive extracorporeal circulation (MiECC) system for patients above 10 kg of weight. We performed a single-center retrospective cohort study of all consecutive patients undergoing bloodless cardiac surgery for congenital heart defects between January 2016 and December 2018.

RESULTS

A total of 164 patients were reviewed (86 male and 78 female) at a median age of 9.6 years (interquartile range (IQR), 4.5-15), a weight of 32 kg (IQR, 16-55), preoperative hemoglobin 13.7 g/dl (IQR, 12.6-14.9), and preoperative hematocrit of 40.4% (IQR, 37.2-44.3). Median CPB time was 81.5 min (IQR, 58-125), and median hematocrit coming off CPB was 26% (IQR, 23-29.7). The congenital heart surgery risk (STAT) category was distributed in STAT 1 for 70, STAT 2 for 80, STAT 3 for 9, and STAT 4 for 5 patients. Most patients (95%) were extubated in the operating room with a low complication rate during the hospital stay (14.6%). Only 6 (4%) patients needed a blood transfusion during the postoperative period, with a higher incidence of complications during the hospital course (p < 0.001).

CONCLUSIONS

Bloodless congenital heart surgery with MiECC system is safe in low-surgical-risk patients. Our patients had a low rate of complications and short hospital stays.

Blood Product Transfusions for Children in the Perioperative Period and for Critically Ill Children

BACKGROUND

Approximately 1% to 2% of all hospitalized children receive a transfusion of blood products, in Germany as in other countries. High-quality scientific evidence on transfusions in children is scarce. The available evidence is discussed in this review.

METHODS

This review is based on publications on blood product transfusions in children that were retrieved by a literature search, including clinical studies, international guideline recommendations, the recommendations of the German cross-sectional guideline, and results of other recent, relevant publications.

RESULTS

A restrictive transfusion strategy is recommended for all children, including those who are critically ill. Randomized controlled trials have shown that a restrictive strategy for erythrocyte concentrate transfusion in the intensive care unit is safe for children, including neonates. No robust data are available to enable the definition of a suitable threshold for the intraoperative administration of red blood cell concentrates in children undergoing extracardiac surgery. On the basis of studies from pediatric intensive care units, transfusions for hemodynamically stable children with a hemoglobin concentration of more than 7 g/dL are recommended only in exceptional cases. Therapeutic plasma is not recommended as volume replacement, except in massive transfusion. Platelet concentrate transfusions are indicated in case of active hemorrhage, and only rarely for prophylaxis.

CONCLUSION

There is a broad lack of evidence from randomized controlled trials concerning the indications for transfusions in children. A restrictive transfusion strategy, which has been found safe in the intensive-care setting, is favored by the guidelines in the perioperative setting as well. Further studies are needed to evaluate transfusion triggers and indications for all types of blood products, especially therapeutic plasma. Until more evidence is available, physicians should be aware of what the current evidence supports, and blood products should be given restrictively, and not prophylactically.

Standard Versus Restrictive Transfusion Strategy for Pediatric Cardiac ECLS Patients: Single Center Retrospective Cohort Study

This retrospective cohort study aimed to compare blood component transfusion before and after the implementation of a restrictive transfusion strategy (RTS) in pediatric cardiac Extracorporeal Life Support (ECLS) patients. The study included children admitted to the pediatric cardiac intensive care unit (PCICU) at the Stollery Children's Hospital who received ECLS between 2012 and 2020. Children on ECLS between 2012 and 2016 were treated with standard transfusion strategy (STS), while those on ECLS between 2016 and 2020 were treated with RTS. During the study, 203 children received ECLS. Daily median (interquartile range [IQR]) packed red blood cell (PRBC) transfusion volume was significantly lower in the RTS group; 26.0 (14.4-41.5) vs. 41.5 (26.6-64.4) ml/kg/day, p value <0.001. The implementation of a RTS led to a median reduction of PRBC transfusion of 14.5 (95% CI: 6.70-21.0) ml/kg/day. Similarly, the RTS group received less platelets: median (IQR) 8.4 (4.50-15.0) vs. 17.5 (9.40-29.0) ml/kg/day, p value <0.001. The implementation of a RTS resulted in a median reduction of platelet transfusion of 9.2 (95% CI: 5.45-13.1) ml/kg/day. The RTS resulted in less median (IQR) fluid accumulation in the first 48 hours: 56.7 (2.30-121.0) vs. 140.4 (33.8-346.2) ml/kg, p value = 0.001. There were no significant differences in mechanical ventilation days, PCICU/hospital days, or survival. The use of RTS resulted in lower blood transfusion volumes, with similar clinical outcomes.

Current hemoglobin thresholds in pediatric anesthesia - guidelines and studies

PURPOSE OF REVIEW

The use of restrictive transfusion triggers to avoid unnecessary transfusions is one important pillar of Patient Blood Management (PBM). For the safe application of this principle in pediatric patients, anesthesiologists need evidence-based guidelines for hemoglobin (Hb) transfusions thresholds in this specially vulnerable age-group.

RECENT FINDINGS

This review outlines recent prospective and observational studies examining transfusion thresholds in pediatrics. Recommendations to use transfusion triggers in the perioperative or intensive care setting are summarized.

SUMMARY

Two high-quality studies confirmed that the use of restrictive transfusion triggers in preterm infants in the intensive care unit (ICU) is reasonable and feasible. Unfortunately, no recent prospective study could be found investigating intraoperative transfusion triggers. Some observational studies showed wide variability in Hb levels before transfusion, a tendency toward restrictive transfusion practices in preterm infants, and liberal transfusion practices in older infants. Although there are comprehensive and useful guidelines for clinical practice in pediatric transfusion, most of them do not cover the intraoperative period in particular because of a lack of high-quality studies. This lack of prospective randomized trials focusing on intraoperative transfusion management remains a major problem for the application of pediatric PBM.

Error traps in Pediatric Patient Blood Management in the Perioperative Period

Patient blood management is a patient-centered evidence-based approach to improve patient outcomes by harnessing the patient's own hematopoietic system to optimize blood health while promoting patient safety and empowerment. Perioperative patient blood management is a standard of care in adult medicine, yet it is not commonly accepted in pediatrics. Raising awareness may be the first step in improving perioperative care for the anemic and/or bleeding child. This article highlights five preventable perioperative blood conservation error traps for children. The goal is to provide practical clinical guidance to improve preoperative diagnosis and treatment of anemia, facilitate recognition and treatment of massive hemorrhage, reduce unnecessary allogeneic blood transfusions, and decrease associated complications of anemia and blood component transfusions utilizing a patient/family-centered informed consent and shared decision-making approach.

Prevalence and determinants of anemia at discharge in pediatric intensive care survivors

BACKGROUND

Restrictive transfusion practices are increasingly being followed in pediatric intensive care units (PICU); consequently, more patients are discharged anemic from PICU. Given the possible impact of anemia on long-term neurodevelopmental outcomes, we aim to describe the epidemiology of anemia at PICU discharge in a mixed (pediatric and cardiac) cohort of PICU survivors and to characterize risk factors for anemia.

STUDY DESIGN AND METHODS

We performed a retrospective cohort study in the PICU of a multidisciplinary tertiary-care university-affiliated center. All consecutive PICU survivors for whom a hemoglobin level was available at PICU discharge were included. Baseline characteristics and hemoglobin levels were extracted from an electronic medical records database.

RESULTS

From January 2013 to January 2018, 4750 patients were admitted to the PICU (97.1% survival); discharge hemoglobin levels were available for 4124 patients. Overall, 50.9% (n = 2100) were anemic at PICU discharge. Anemia at PICU discharge was also common in the cardiac surgery population (53.3%), mainly in acyanotic patients; only 24.6% of cyanotic patients were anemic according to standard definitions of anemia. Cardiac surgery patients were transfused more often and at higher hemoglobin levels than medical and non-cardiac surgery patients. Anemia at admission was the strongest predictor of anemia at discharge (odds ratios (OR): 6.51, 95% confidence interval (CI:5.40;7.85)).

DISCUSSION

Half of PICU survivors are anemic at discharge. Further studies are required to determine the course of anemia after discharge and to ascertain whether anemia is associated with adverse long-term outcomes.

The Impact of Restrictive Transfusion Practices on Hemodynamically Stable Critically Ill Children Without Heart Disease: A Secondary Analysis of the Age of Blood in Children in the PICU Trial

OBJECTIVES

Guidelines recommend against RBC transfusion in hemodynamically stable (HDS) children without cardiac disease, if hemoglobin is greater than or equal to 7 g/dL. We sought to assess the clinical and economic impact of compliance with RBC transfusion guidelines.

DESIGN

A nonprespecified secondary analysis of noncardiac, HDS patients in the randomized trial Age of Blood in Children (NCT01977547) in PICUs. Costs analyzed included ICU stay and physician fees. Stabilized inverse propensity for treatment weighting was used to create a cohort balanced with respect to potential confounding variables. Weighted regression models were fit to evaluate outcomes based on guideline compliance.

SETTING

Fifty international tertiary care centers.

PATIENTS

Critically ill children 3 days to 16 years old transfused RBCs at less than or equal to 7 days of ICU admission. Six-hundred eighty-seven subjects who met eligibility criteria were included in the analysis.

INTERVENTIONS

Initial RBC transfusions administered when hemoglobin was less than 7 g/dL were considered "compliant" or "non-compliant" if hemoglobin was greater than or equal to 7 g/dL.

MEASUREMENTS AND MAIN RESULTS

Frequency of new or progressive multiple organ system dysfunction (NPMODS), ICU survival, and associated costs. The hypothesis was formulated after data collection but exposure groups were masked until completion of planned analyses. Forty-nine percent of patients (338/687) received a noncompliant initial transfusion. Weighted cohorts were balanced with respect to confounding variables (absolute standardized differences < 0.1). No differences were noted in NPMODS frequency (relative risk, 0.86; 95% CI, 0.61-1.22; p = 0.4). Patients receiving compliant transfusions had more ICU-free days (mean difference, 1.73; 95% CI, 0.57-2.88; p = 0.003). Compliance reduced mean costs in ICU by $38,845 U.S. dollars per patient (95% CI, $65,048-$12,641).

CONCLUSIONS

Deferring transfusion until hemoglobin is less than 7 g/dL is not associated with increased organ dysfunction in this population but is independently associated with increased likelihood of live ICU discharge and lower ICU costs.

Perioperative Pediatric Erythrocyte Transfusions: Incorporating Hemoglobin Thresholds and Physiologic Parameters in Decision-making

This article presents current literature and scientific evidence on hemoglobin thresholds and physiologic parameters to guide decisions regarding perioperative erythrocyte transfusions in pediatric patients based on the most up-to-date studies and expert consensus recommendations.

A Surgeon's Perspective on Blood Conservation Practice in Pediatric Cardiac Surgery

Blood conservation practice in pediatric cardiac surgery has not been consistently adopted as quality improvement in many centers despite known risks associated with allogeneic blood products, shortage of donors, and costs. There are many blood conservation strategies available which collectively minimize exposure to allogeneic transfusion by maximizing the use of autologous red cells. These strategies are safe, reproducible, and have been implemented in clinical practice collectively with great efficacy for all patient ages and complexity levels. Institutional commitment to a set guideline will improve their blood conservation practice and quality outcome. The purpose of this article is to provide early career and practicing congenital cardiac surgeons with practical information concerning blood conservation strategies which can be considered for implementation in any pediatric cardiac surgery program, and which may be of particular value in resource-limited programs.

Transfusion therapy of neonatal and paediatric patients: They are not just little adults

Patient blood management (PBM) strategies are needed in the neonate and paediatric population, given that haemoglobin thresholds used are often higher than recommended by evidence, with exposure of children to potential complications without meaningful benefit. A literature review was performed on the following topics: evidence-based transfusions of blood components and pharmaceutical agents. Other topics reviewed included perioperative coagulation assessment and perioperative PBM. The Transfusion and Anaemia Expertise Initiative (TAXI) consortium published a consensus statement addressing haemoglobin (Hb) transfusion threshold in multiple subsets of patients. A multicentre trial (PlaNeT-2) reported a higher risk of bleeding and death or serious new bleeding among infants who received platelet transfusion at a higher (50 000/μl) compared to a lower (25 000/μl) threshold. Recent data support the use of a restrictive transfusion threshold of 25 000/μl for prophylactic platelet transfusions in preterm neonates. The TAXI-CAB consortium mentioned that in critically ill paediatric patients undergoing invasive procedures outside of the operating room, platelet transfusion might be considered when the platelet count is less than or equal to 20 000/μl and there is no benefit of platelet transfusion when the platelet count is more than 50 000/μl. There are limited controlled studies in paediatric and neonatal population regarding plasma transfusion. Blood conservation strategies to minimise allogenic blood exposure are essential to positive patient outcomes neonatal and paediatric transfusion practices have changed significantly in recent years since randomised controlled trials were published to guide practice. Additional studies are needed in order to provide practice change recommendations.

Transfusion Practices in Pediatric Cardiac Surgery Requiring Cardiopulmonary Bypass: A Secondary Analysis of a Clinical Database

OBJECTIVES

To describe blood component usage in transfused children with congenital heart disease undergoing cardiopulmonary bypass surgery across perioperative settings and diagnostic categories.

DESIGN

Datasets from U.S. hospitals participating in the National Heart, Lung, and Blood Institute Recipient Epidemiology and Donor Evaluation Study-III were analyzed.

SETTING

Inpatient admissions from three U.S. hospitals from 2013 to 2016.

PATIENTS

Transfused children with congenital heart disease undergoing single ventricular, biventricular surgery, extracorporeal membrane oxygenation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Eight hundred eighty-two transfused patients were included. Most of the 185 children with single ventricular surgery received multiple blood products: 81% RBCs, 79% platelets, 86% plasma, and 56% cryoprecipitate. In the 678 patients undergoing biventricular surgery, 85% were transfused plasma, 75% platelets, 74% RBCs, and 48% cryoprecipitate. All 19 patients on extracorporeal membrane oxygenation were transfused RBCs, plasma, and cryoprecipitate, and 18 were transfused platelets. Intraoperatively, patients commonly received all three components, while postoperative transfusions were predominantly single blood components. Pretransfusion hemoglobin values were normal/low-normal for age for all phases of care for single ventricular surgery (median hemoglobin 13.2-13.5 g/dL). Pretransfusion hemoglobin values for biventricular surgeries were higher intraoperatively compared with other timing (12.2 g/dL vs 11.2 preoperative and postoperative; p < 0.0001). Plasma transfusions for all patients were associated with a near normal international normalized ratio: single ventricular surgeries median international normalized ratio was 1.3 postoperative versus 1.8 intraoperative and biventricular surgeries median international normalized ratio was 1.1 intraoperative versus 1.7 postoperative. Intraoperative platelet transfusions with biventricular surgeries had higher median platelet count compared with postoperative pretransfusion platelet count (244 × 109/L intraoperative vs 69 × 109/L postoperative).

CONCLUSIONS

Children with congenital heart disease undergoing cardiopulmonary bypass surgery are transfused many blood components both intraoperatively and postoperatively. Multiple blood components are transfused intraoperatively at seemingly normal/low-normal pretransfusion values. Pediatric evidence guiding blood component transfusion in this population at high risk of bleeding and with limited physiologic reserve is needed to advance safe and effective blood conservation practices.

Understanding and managing the complex balance between bleeding and thrombosis following cardiopulmonary bypass in paediatric cardiac surgical patients

Bleeding in the perioperative period of congenital heart surgery with cardiopulmonary bypass is associated with increased morbidity and mortality both from the direct effects of haemorrhage as well as the therapies deployed to restore haemostasis. Perioperative bleeding is complex and multifactorial with both patient and procedural contributions. Moreover, neonates and infants are especially at risk. The objective of this review is to summarise the evidence regarding bleeding management in paediatric surgical patients and identify strategies that might facilitate appropriate bleeding management while minimising the risk of thrombosis. We will address the use of standard and point-of-care tests, and the role of contemporary coagulation factors and other novel drugs.

Anemia after Pediatric Congenital Heart Surgery

The postoperative course of infants following congenital heart surgery is associated with significant blood loss and anemia. Optimal transfusion thresholds for cardiac surgery patients while in pediatric intensive care unit (PICU) remain a subject of debate. The goal of this study is to describe the epidemiology of anemia and the transfusion practices during the PICU stay of infants undergoing congenital heart surgery. A retrospective cohort study was performed in a PICU of a tertiary university-affiliated center. Infants undergoing surgery for congenital heart disease (CDH) before 6 weeks of age between February 2013 and June 2019 and who were subsequently admitted to the PICU were included. We identified 119 eligible patients. Mean age at surgery was 11 ± 7 days. Most common cardiac diagnoses were d-Transposition of the Great Arteries (55%), coarctation of the aorta (12.6%), and tetralogy of Fallot (11.8%). Mean hemoglobin level was 14.3 g/dL prior to surgery versus 12.1 g/dL at the PICU admission. Hemoglobin prior to surgery was systematically higher than hemoglobin at the PICU entry, except in infants with Hypoplastic Left Heart Syndrome. The average hemoglobin at PICU discharge was 11.7 ± 1.9 g/dL. Thirty-three (27.7%) patients were anemic at PICU discharge. Fifty-eight percent of patients received at least one red blood cell (RBC) transfusion during PICU stay. This study is the first to describe the epidemiology of anemia at PICU discharge in infants following cardiac surgery. Blood management of this distinctive and vulnerable population requires further investigation as anemia is a known risk factor for adverse neurodevelopment delays in otherwise healthy young children.

Near-Infrared Spectroscopy Monitoring in Pediatric Anesthesiology: A Pro-Con Discussion

Near-infrared spectroscopy (NIRS) has been increasingly used as a non-invasive measurement of cerebral tissue oxygen saturation. The aim of this short review is to discuss the benefits and drawbacks of its use in the pediatric anesthesia population. In the context of cardiac surgery, lower intraoperative NIRS values have shown a modest association with neurodevelopmental outcomes while lower neonatal intensive care unit NIRS values have been correlated with reduced neurodevelopment in children. However, it is still unclear if management aimed at increasing cerebral tissue oxygenation would have any benefit on these outcomes. Without prospective research looking into the effects of intervention given proper thresholds, the true benefit of NIRS use is still up for debate. Even with current research gaps, its use in the clinical setting continues.

Transfusion in Pediatric Patients: Review of Evidence-Based Guidelines

Children require transfusion of blood components for a vast array of medical conditions, including acute hemorrhage, hematologic and nonhematologic malignancies, hemoglobinopathy, and allogeneic and autologous stem cell transplant. Evidence-based literature on pediatric transfusion practices is limited, particularly for non-red blood cell products, and many recommendations are extrapolated from studies in adult populations. Recognition of these knowledge gaps has led to increasing numbers of clinical trials focusing on children and establishment of pediatric transfusion working groups in recent years. This article reviews existing literature on pediatric transfusion therapy within the larger context of analogous data in adult populations.

Transfusion Strategies for Pediatric Cardiac Surgery: A Meta-Analysis and Trial Sequential Analysis

This study aimed to compare the effects of restrictive and liberal red blood cell (RBC) transfusion strategies on pediatric patients undergoing cardiac surgery, including cyanotic and non-cyanotic children. A literature search of the MEDLINE, EMBASE, PubMed, and the Cochrane Library database was conducted. Meta-analyses were carried out comparing restrictive and liberal transfusion strategies. Subgroup analyses were performed based on the basis of cyanotic status. Five randomized controlled trials with a total of 497 children were included. There was no significant difference in the risk of in-hospital mortality between the two transfusion strategies (risk ratio 1.21; 95% confidence interval 0.49 to 2.99; P = 0.68). The trial sequential analysis suggested that the current meta-analysis had an absence of evidence for in-hospital mortality, and the data were insufficient. Moreover, no significant differences existed between groups in terms of risk of infection, blood loss, duration of mechanical ventilation, pediatric intensive care unit (PICU) stay duration, or hospital stay duration. Cyanotic children treated with a liberal transfusion strategy had a shorter ventilator duration, but the transfusion strategy did not affect in-hospital mortality, infection, hospital stay, or PICU stay duration. On the basis of the available data, our analysis indicates that a liberal transfusion strategy did not lead to a better outcomes, but the data are extremely sparse, which highlights the need for clearer transfusion guidelines specific to this specific population.Trial registration number CRD42018102283.

Factors Influencing Implementation of Blood Transfusion Recommendations in Pediatric Critical Care Units

Purpose: Risks of red blood cell transfusion may outweigh benefits for many patients in Pediatric Intensive Care Units (PICUs). The Transfusion and Anemia eXpertise Initiative (TAXI) recommendations seek to limit unnecessary and potentially harmful transfusions, but use has been variable. We sought to identify barriers and facilitators to using the TAXI recommendations to inform implementation efforts. Materials and Methods: The integrated Promoting Action on Research Implementation in Health Services (iPARIHS) framework guided semi-structured interviews conducted in 8 U.S. ICUs; 50 providers in multiple ICU roles completed interviews. Adapted Framework analysis, a form of content analysis, used the iPARIHS innovation, recipient, context and facilitation constructs and subconstructs to categorize data and identify patterns as well as unique informative statements. Results: Providers perceived that the TAXI recommendations would reduce transfusion rates and practice variability, but adoption faced challenges posed by attitudes around transfusion and care in busy and complex units. Development of widespread buy-in and inclusion in implementation, integration into workflow, designating committed champions, and monitoring outcomes data were expected to enhance implementation. Conclusions: Targeted activities to create buy-in, educate, and plan for use are necessary for TAXI implementation. Recognition of contextual challenges posed by the PICU environment and an approach that adjusts for barriers may optimize adoption.

Validation of a Novel NeurOs Cerebral Oximetry Monitor Against the INVOS Monitor During Cardiac Surgery

OBJECTIVES

To compare the performance of a novel NeurOs cerebral oximetry monitor against the INVOS monitor during the entire intraoperative phase of cardiac surgery, including periods of known fluctuation in brain oxygenation, such as preoxygenation, induction, cannulation, and cardiopulmonary bypass.

DESIGN

This study was a prospective, nonrandomized, healthcare-provider and outcome-assessor blinded study.

SETTING

Tertiary care university hospital; single institutional study.

PARTICIPANTS

Twenty-three patients who underwent cardiac surgery with cardiopulmonary bypass.

INTERVENTIONS

Both self-adhesive INVOS sensors and the assembled NeurOs sensors were placed accordingly when the patient arrived in the operating room.

MEASUREMENTS AND MAIN RESULTS

Ten out of 13 cases under the normal mode and eight out of the 10 cases under the high- sensitivity mode showed significant correlations between the NeurOs and INVOS groups (p < 0.05, r value from 0.24-0.88). When all cases were combined, NeurOs demonstrated significant correlation with INVOS (r = 0.5, 95% confidence interval [CI] 0.44-0.56, p < 0.01 for normal mode; r = 0.69, 95% CI 0.64 to 0.74, p < 0.01 for high-sensitivity mode) in both modes. To evaluate the data diversity, the authors performed a cluster analysis and found much less variation existed in the NeurOs normal mode when compared with INVOS (standard deviation [SD] 16.6% in INVOS, 4% in NeurOs normal mode) but similar patterns in the high-sensitivity mode (SD 17.6% in INVOS, 15.2% in NeurOs high-sensitivity mode). Bland-Altman plot analysis showed that most of the data fell between ± 1.96 SD lines, which demonstrated good consistency between these two methods under both modes of NeurOs (-28.8 to 30.8 in the normal mode; -36.6 to 32.7 in high-sensitivity mode). In the normal mode of NeurOs monitoring, receiver operating characteristic analysis suggested a 2% cutoff point was most optimal from the baseline for detecting hyperoxia (sensitivity 73%; specificity 66%) and minus 1% (sensitivity 66%; specificity 67%) for detecting hypoxia. Whereas in the high-sensitivity mode, the optimal cutoff point was 3% from baseline for detecting hyperoxia (sensitivity 75%; specificity 68%), and minus 3% for detecting hypoxia (sensitivity 90%; specificity 45%).

CONCLUSIONS

In conclusion, the novel NeurOs system was found to correlate with INVOS cerebral oximetry measurements during cardiac surgery.

Are Blood Products Routinely Required in Pediatric Heart Surgery?

A restrictive blood transfusion strategy has emerged in adult cardiac surgery. However, the feasibility in children is poorly investigated. 352 consecutive patients undergoing open-heart surgery were retrospectively reviewed, excluding patients requiring extracorporeal membrane oxygenation. Patient demographics, perioperative blood product usage, and clinical outcome parameters were investigated. Variables predicting the need for blood products were delineated. Of the 352 study patients, 148 patients (42%) underwent bloodless surgery and 204 (58%) were transfused. Of the 204 transfused patients, 170 (83.4%) patients received one blood transfusion and 34 (16.6%) received two or more blood transfusions. Patient's weight and preoperative hematocrit (Hct) were statistically significant in predicting the need for blood priming the CPB circuit (AUC 0.99, p < 0.001, sensitivity 96.6%, specificity 95.2%). A body weight of 8.5 kg carried a sensitivity of 100% and specificity of 94.5% (p < 0.001) for a blood prime. Among patients with a weight less than 8.5 kg (n = 171), only 27 patients (15.8%, p < 0.001) required additional transfusion of PRBCs. Factors impacting the need for a blood transfusion during CPB included redo surgery [odds ratio (OR) 4.61, p = 0.001] and the highest lactate level on CPB (OR 1.65, p = 0.006). Redo surgery had the highest impact (OR 7.27, p = 0.012) for requiring a postoperative PRBC transfusion. A restrictive transfusion strategy can be safely implemented in pediatric cardiac surgery. The majority of children with a BW > 8.5 kg required no blood products and those with a BW ≤ 8.5 kg required only 1 unit of blood, to prime the cardiopulmonary bypass circuit.

How 217 Pediatric Intensivists Manage Anemia at PICU Discharge: Online Responses to an International Survey

OBJECTIVE

To describe the management of anemia at PICU discharge by pediatric intensivists.

DESIGN

Self-administered, online, scenario-based survey.

SETTING

PICUs in Australia/New Zealand, Europe, and North America.

SUBJECTS

Pediatric intensivists.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Respondents were asked to report their decisions regarding RBC transfusions, iron, and erythropoietin prescription to children ready to be discharged from PICU, who had been admitted for hemorrhagic shock, cardiac surgery, craniofacial surgery, and polytrauma. Clinical and biological variables were altered separately in order to assess their effect on the management of anemia. Two-hundred seventeen responses were analyzed. They reported that the mean (± SEM) transfusion threshold was a hemoglobin level of 6.9 ± 0.09 g/dL after hemorrhagic shock, 7.6 ± 0.10 g/dL after cardiac surgery, 7.0 ± 0.10 g/dL after craniofacial surgery, and 7.0 ± 0.10 g/dL after polytrauma (p < 0.001). The most important increase in transfusion threshold was observed in the presence of a cyanotic heart disease (mean increase ranging from 1.80 to 2.30 g/dL when compared with baseline scenario) or left ventricular dysfunction (mean increase, 1.41-2.15 g/dL). One third of respondents stated that they would not prescribe iron at PICU discharge, regardless of the hemoglobin level or the baseline scenario. Most respondents (69.4-75.0%, depending on the scenario) did not prescribe erythropoietin.

CONCLUSIONS

Pediatric intensivists state that they use restrictive transfusion strategies at PICU discharge similar to those they use during the acute phase of critical illness. Supplemental iron is less frequently prescribed than RBCs, and prescription of erythropoietin is uncommon. Optimal management of post-PICU anemia is currently unknown. Further studies are required to highlight the consequences of this anemia and to determine appropriate management.

Red Blood Cell Transfusion After Stage I Palliation Is Associated With Worse Clinical Outcomes

Background Packed red blood cell transfusion may improve oxygen content in single-ventricle neonates, but its effect on clinical outcomes after Stage 1 palliation is unknown. Methods and Results Retrospective multicenter analysis of packed red blood cell transfusion exposures in neonates after Stage 1 palliation, excluding those with intraoperative mortality or need for extracorporeal membrane oxygenation. Transfusion practice variability was assessed, and multivariable regression used to identify transfusion risk factors. After propensity score adjustment for severity of illness, clinical outcomes were compared between transfused and nontransfused subjects. Of 396 subjects, 323 (82%) received 930 postoperative red blood cell transfusions. Packed red blood cell volume (median 9-42 mL/kg [P<0.0001]), donor exposures (1-2 [P<0.0001]), transfusion number (1-3 [P<0.0001]), and pretransfusion hemoglobin (12.1-13 g/dL, P=0.0049) varied between sites. Cyanosis (P=0.02), chest tube output (P=0.0003), and delayed sternal closure (P=0.0033) increased transfusion risk. Transfusion was associated with prolonged mechanical ventilation (6 [interquartile range 4, 12] versus 3 [1, 5] days, P=0.02) and intensive care unit stay (19 [12, 33] versus 9 [6, 19] days, P=0.016). When stratified by number of transfusions (0, 1, or >1), duration of mechanical ventilation (3 [1, 5] versus 4 [3, 6] versus 9 [5, 16] days [P<0.0001]) and intensive care unit stay (9 [6, 19] versus 13 [8, 25] versus 21 [13, 38] days [P<0.0001]) increased for those transfused more than once. Most subjects who died were transfused, though the association with mortality was not significant. Conclusions Packed red blood cell transfusion after Stage 1 palliation is common, and transfusion practice is variable. Transfusion is a significant predictor of longer intensive care unit stay and mechanical ventilation. Further studies to define evidence-based transfusion thresholds are warranted.

Red cell transfusion practices after stage 1 palliation: a survey of practitioners from the Pediatric Cardiac Intensive Care Society

INTRODUCTION

Neonates may require increased red cell mass to optimise oxygen content after stage 1 palliation; however, data informing transfusion practices are limited. We hypothesise there is a patient-, provider-, and institution-based heterogeneity in red cell transfusion decision-making after stage 1 palliation.

METHODS

We conducted an online survey of Pediatric Cardiac Intensive Care Society practitioners in 2016. Respondents answered scenario-based questions that defined transfusion indications and identified haematocrit transfusion thresholds. Respondents were divided into restrictive and liberal groups based on a haematocrit score. Fisher's exact test was used to determine the associations between transfusion likelihood and patient, provider, and institutional characteristics. Bonferroni correction was applied to adjust the p-value to 0.004 for multiple comparisons.

RESULTS

There was a 21% response rate (116 responses). Most were male (58.6%), attending physicians (85.3%) with >5 year of intensive care experience (88.7%) and subspeciality training in critical care medicine (47.4%). The majority of institutions were academic (96.6%), with a separate cardiac ICU (86.2%), and performed >10 stage 1 palliation cases annually (68.1%). After Bonferroni correction, there were no significant patient, respondent, or institutional differences between the restrictive and liberal groups. No respondent or institutional characteristics influenced transfusion decision-making after stage 1 palliation.

CONCLUSIONS

Decision-making around red cell transfusion after stage 1 palliation is heterogeneous. We found no clear relationships between patient, respondent, or institutional characteristics and transfusion decision-making among surveyed respondents. Given the lack of existing data informing red cell transfusion after stage 1 palliation, further studies are necessary to inform evidence-based guidelines.

Patient Blood Management in Pediatric Cardiac Surgery: A Review

Efforts to reduce blood product transfusions and adopt blood conservation strategies for infants and children undergoing cardiac surgical procedures are ongoing. Children typically receive red blood cell and coagulant blood products perioperatively for many reasons, including developmental alterations of their hemostatic system, and hemodilution and hypothermia with cardiopulmonary bypass that incites inflammation and coagulopathy and requires systemic anticoagulation. The complexity of their surgical procedures, complex cardiopulmonary interactions, and risk for inadequate oxygen delivery and postoperative bleeding further contribute to blood product utilization in this vulnerable population. Despite these challenges, safe conservative blood management practices spanning the pre-, intra-, and postoperative periods are being developed and are associated with reduced blood product transfusions. This review summarizes the available evidence regarding anemia management and blood transfusion practices in the perioperative care of these critically ill children. The evidence suggests that adoption of a comprehensive blood management approach decreases blood transfusions, but the impact on clinical outcomes is less well studied and represents an area that deserves further investigation.

Met-Hemoglobin Is a Biomarker for Poor Oxygen Delivery in Infants Following Surgical Palliation

BACKGROUND

Infants with cyanotic congenital heart disease demonstrate wide fluctuations in hemoglobin (Hb), oxygen saturation, and cardiac output following palliation. Methemoglobin (Met-Hb), the product of Hb oxidation, may represent a compensatory mechanism during hypoxia and may be utilized as a biomarker.

METHODS

Arterial and venous Met-Hb levels were obtained from infants requiring palliation. The primary outcome was to describe the relationship between Met-Hb and other indices of tissue oxygenation (venous saturation, estimated arteriovenous oxygen difference [Est AV-Diff], and lactate). Secondary outcomes were to determine the impact of elevated Met-Hb levels ≥1.0% and the effect of red blood cell (RBC) transfusion on Met-Hb levels.

RESULTS

Fifty infants and 465 Met-Hb values were studied. Venous Met-Hb levels were significantly higher than arterial levels (venous: 0.84% ± 0.36% vs arterial: 0.45% ± 0.18%; P < .001). Venous Met-Hb demonstrated a significant inverse relationship with venous oxygen saturation (R = -0.6; P < .001) and Hb (R = -0.3, P < .001) and a direct relationship with the Est AV-Diff (R = 0.3, P < .001). A total of 129 (29.6%) venous Met-Hb values were elevated (≥1.0%) and were associated with significantly lower Hb and venous saturation levels and higher Est AV-Diff and lactate levels. Methemoglobin levels decreased significantly following 65 RBC transfusions (0.94 ± 0.40 vs 0.77 ± 0.34; P < .001). Linear mixed models demonstrated that higher venous Met-Hb levels were associated with lower measures of tissue oxygenation and not related to any preoperative clinical differences.

CONCLUSION

Methemoglobin may be a clinically useful marker of tissue oxygenation in infants following surgical palliation.

Standardized Implementation of Evidence-based Guidelines to Decrease Blood Transfusions in Pediatric Intensive Care Units

Introduction

Despite evidence that red blood cell (RBC) transfusions may be associated with more harm than benefit, current transfusion practices vary significantly. This multicenter, quality improvement study aimed to sustainably decrease the rate of RBC transfusions in pediatric intensive care units (PICUs).

Methods

This 16-month prospective study included 5 PICUs. We implemented a standardized project plan including education, bedside tools, real-time reminders, and email feedback. We collected data from consecutive transfusions during pre-implementation (Phase I), postimplementation (Phase II), and post-stabilization phases (Phase III).

Results

Of the 2,064 RBC transfusions, we excluded 35% (N = 729) from analysis in patients undergoing extracorporeal membrane oxygenation. Transfusion/1,000 admissions improved throughout the study periods from a baseline 209.6 -199.8 in Phase II and 195.8 in Phase III (P value < 0.05). There were fewer transfusions outside of the hemoglobin threshold guideline, decreasing from 81% of transfusions outside of guidelines in Phase I to 74% in Phases II and III, P < 0.05. Study phase, site, co-management status, service of requesting provider, admit reason, previous transfusion status, and age were associated with transfusion above guideline threshold.

Conclusions

Multicenter collaboration can successfully deploy a standardized plan that adheres to implementation science principles to sustainably decrease the rate of RBC transfusion outside of guideline thresholds. However, we did not decrease the total number of transfusions in our study. The complexity of multiple specialties co-managing patients is common in the contemporary PICU. Educational initiatives aimed at one specialty may have limited effectiveness in a multifaceted system of care.

Restrictive compared with liberal red cell transfusion strategies in cardiac surgery: a meta-analysis

AIMS

To determine whether a restrictive strategy of red blood cell (RBC) transfusion at lower haemoglobin concentrations is inferior to a liberal strategy of RBC transfusion at higher haemoglobin concentrations in patients undergoing cardiac surgery.

METHODS AND RESULTS

We conducted a systematic review, meta-analysis, and trial sequential analysis of randomized controlled trials of the effect of restrictive and liberal RBC transfusion strategies on mortality within 30 days of surgery as the primary outcome. Secondary outcomes were those potentially resulting from anaemia-induced tissue hypoxia and transfusion outcomes. We searched the electronic databases MEDLINE, EMBASE, and the Cochrane Library until 17 November 2017. Thirteen trials were included. The risk ratio (RR) of mortality derived from 4545 patients assigned to a restrictive strategy when compared with 4547 transfused according to a liberal strategy was 0.96 [95% confidence interval (CI) 0.76-1.21, I2 = 0]. A restrictive strategy did not have a statistically significant effect on the risk of myocardial infarction (RR 1.01, 95% CI 0.81-1.26; I2=0), stroke (RR 0.93, 95% CI 0.68-1.27, I2 = 0), renal failure (RR 0.96, 95% CI 0.76-1.20, I2 = 0), or infection (RR 1.12, 95% CI 0.98-1.29, I2 = 0). Subgroup analysis of adult and paediatric trials did not show a significant interaction. At approximately 70% of the critical information size, the meta-analysis of mortality crossed the futility boundary for inferiority of the restrictive strategy.

CONCLUSION

The current evidence does not support the notion that restrictive RBC transfusion strategies are inferior to liberal RBC strategies in patients undergoing cardiac surgery.

Complications of Transthoracic Intracardiac and Central Venous Lines in Neonates Undergoing Cardiac Surgery

Neonates undergoing congenital heart surgery require central venous access for diagnostic information and medication administration. There are multiple options for central access including peripherally inserted central catheters, umbilical, central venous, and transthoracic intracardiac lines. We retrospectively identified all patients younger than 30 days who underwent cardiac surgery in a 1-year period. Data were collected on demographic and medical characteristics, adverse events, pre-emptive transfusion of blood products prior to line removal, and transfusion of blood products following removal of transthoracic intracardiac lines and central venous lines. In our cohort of 124 neonates, 176 transthoracic intracardiac lines were placed in 113 patients. Eighty-two patients had pre-existing central venous access including 35 umbilical venous lines, 21 PICC lines, and 18 CVLs. Ninety-eight patients received a CVL in the operating room by anesthesia. Five patients were transfused to correct laboratory derangement prior to transthoracic intracardiac line removal. Transfusion of packed red blood cells (pRBC) occurred after transthoracic intracardiac line removal in 25 patients. Thrombus formation was present in one patient with a transthoracic intracardiac line and three patients with CVLs. One patient underwent surgical intervention for repositioning of a transthoracic intracardiac line. There were no cases of cardiac arrest, extracorporeal life support, or deaths attributable to lines. In this cohort, transthoracic intracardiac lines were generally safe. There were very few complications of thrombus, infection, or requirement for surgical intervention; however, transfusion of pRBCs following transthoracic intracardiac line removal occurred in 20% of patients.

Cyanotic heart disease is an independent predicting factor for fresh frozen plasma and platelet transfusion after cardiac surgery

OBJECTIVES

Cyanotic heart disease is associated with increased risk of bleeding in children undergoing cardiac surgery. We studied if the presence of a cyanotic heart disease was an independent predictive factor for fresh frozen plasma (FFP) and platelets transfusion in these patients. In children with ROTEM measurements, we also tried to characterize the coagulation profile between both groups.

DESIGN

Retrospective observational study.

SETTING

Tertiary university hospital; single center.

PARTICIPANTS

All consecutive children admitted for cardiac surgery with cardiopulmonary bypass (CPB) from January 2006 to December 2014. Patients who received FFP in the CPB priming were excluded. Multivariate logistic regression was used to determine the predictive factors for FFP and platelet transfusions.

INTERVENTION

none.

MEASUREMENTS AND MAIN RESULTS

From the 1846 patients included for analysis: 1063 were acyanotic and 783 were cyanotic. The presence of cyanotic heart disease was an independent predicting factor for both FFP (OR: 2.09; 95%CI: 1.44-3.02) and platelets (OR:3.98; 95%CI: 2.28-6.70) transfusion. Cyanotic children exhibited also higher perioperative blood losses [Intraoperative: 31.1 (17.6-50.4) versus 26.7 (14.8-44.7); P < 0.001 and Postoperative: 31.2 (19.1-51.9) versus 16.9 (10.4-26.9); P < 0.001]. Thromboelastometry assays after separation from CPB and heparin reversal revealed more complex coagulation disturbances in cyanotic than acyanotic children.

CONCLUSION

Children with a cyanotic heart disease are at higher risk of FFP and platelet transfusion after cardiac surgery. Intraoperative monitoring should be used to guide administration of blood and haemostatic product in this population at high risk of postoperative bleeding.

Red blood cell transfusion threshold after pediatric cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Restrictive red blood cell transfusion strategy is implemented to minimize risk following allogeneic blood transfusion in adult cardiac surgery. However, it is still unclear if it can be applied to pediatric cardiac patients. The purpose of this systematic review and meta-analysis was to determine the effect of postoperative restrictive transfusion thresholds on clinical outcomes based on up-to-date results of randomized controlled trials (RCTs) and observational studies in pediatric cardiac surgery.

METHOD

We searched for RCTs and observational studies in the following databases: the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and ClinicalTrials.gov from their inception to October 26, 2017. We also searched reference lists of published guidelines, reviews, and relevant articles, as well as conference proceedings. No language restrictions were applied and no observational study met the inclusion criteria.

RESULTS

Four RCTs on cardiac surgery involving 454 patients were included. There were no differences in the pooled fixed effects of intensive care unit (ICU) stay between the liberal and restrictive transfusion thresholds (standardized mean difference SMD, 0.007; 95% confidence interval CI, -0.18-0.19; P = .94). There were also no differences in the length of hospital stay (SMD, -0.062; 95% CI, -0.28-0.15; P = .57), ventilation duration (SMD, -0.015; 95% CI, -0.25-0.22; P = .90), mean arterial lactate level (SMD, 0.071; 95% CI, -0.22-0.36; P = .63), and mortality (risk ratio, 0.49; 95% CI, 0.13-1.94; P = .31). There was no inter-trial heterogeneity for any pooled analysis. Publication bias was tested using Egger, Begg, or the trim-and-fill test, and the results indicated no significant publication bias.

CONCLUSION

Evidence from RCTs in pediatric cardiac surgery, though limited, showed non-inferiority of restrictive thresholds over liberal thresholds in length of ICU stay and other outcomes following red blood cell transfusion. Further high-quality RCTs are necessary to confirm the findings.

Recommendations on RBC Transfusion in General Critically Ill Children Based on Hemoglobin and/or Physiologic Thresholds From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To present the consensus recommendations and supporting literature for RBC transfusions in general critically ill children from the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

Consensus conference series of international, multidisciplinary experts in RBC transfusion management of critically ill children.

METHODS

The panel of 38 experts developed evidence-based and, when evidence was lacking, expert-based recommendations and research priorities regarding RBC transfusions in critically ill children. The subgroup on RBC transfusion in general critically ill children included six experts. Electronic searches were conducted using PubMed, EMBASE, and Cochrane Library databases from 1980 to May 30, 2017, using a combination of keywords to define concepts of RBC transfusion and critically ill children. Recommendation consensus was obtained using the Research and Development/UCLA Appropriateness Method. The results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method.

RESULTS

Three adjudicators reviewed 4,399 abstracts; 71 papers were read, and 17 were retained. Three papers were added manually. The general Transfusion and Anemia Expertise Initiative subgroup developed, and all Transfusion and Anemia Expertise Initiative members voted on two good practice statements, six recommendations, and 11 research questions; in all instances, agreement was reached (> 80%). The good practice statements suggest a framework for RBC transfusion in PICU patients. The good practice statements and recommendations focus on hemoglobin as a threshold and/or target. The research questions focus on hemoglobin and physiologic thresholds for RBC transfusion, alternatives, and risk/benefit ratio of transfusion.

CONCLUSIONS

Transfusion and Anemia Expertise Initiative developed pediatric-specific good practice statements and recommendations regarding RBC transfusion management in the general PICU population, as well as recommendations to guide future research priorities. Clinical recommendations emphasized relevant hemoglobin thresholds, and research recommendations emphasized a need for further understanding of physiologic thresholds, alternatives to RBC transfusion, and hemoglobin thresholds in populations with limited pediatric literature.

Recommendations on RBC Transfusion in Infants and Children With Acquired and Congenital Heart Disease From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To present the recommendations and supporting literature for RBC transfusions in critically ill children with acquired and congenital heart disease developed by the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

Consensus conference series of 38 international, multidisciplinary experts in RBC transfusion management of critically ill children.

METHODS

Experts developed evidence-based and, when evidence was lacking, expert-based clinical recommendations and research priorities for RBC transfusions in critically ill children. The cardiac disease subgroup included three experts. Electronic searches were conducted using PubMed, EMBASE, and Cochrane Library databases from 1980 to May 2017. Agreement was obtained using the Research and Development/UCLA appropriateness method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method.

RESULTS

Twenty-one recommendations were developed and reached agreement. For children with myocardial dysfunction and/or pulmonary hypertension, there is no evidence that transfusion greater than hemoglobin of 10 g/dL is beneficial. For children with uncorrected heart disease, we recommended maintaining hemoglobin greater than 7-9.0 g/dL depending upon their cardiopulmonary reserve. For stable children undergoing biventricular repairs, we recommend not transfusing if the hemoglobin is greater than 7.0 g/dL. For infants undergoing staged palliative procedures with stable hemodynamics, we recommend avoiding transfusions solely based upon hemoglobin, if hemoglobin is greater than 9.0 g/dL. We recommend intraoperative and postoperative blood conservation measures. There are insufficient data supporting shorter storage duration RBCs. The risks and benefits of RBC transfusions in children with cardiac disease requires further study.

CONCLUSIONS

We present RBC transfusion management recommendations for the critically ill child with cardiac disease. Clinical recommendations emphasize relevant hemoglobin thresholds, and research recommendations emphasize need for further understanding of physiologic and hemoglobin thresholds and alternatives to RBC transfusion in subpopulations lacking pediatric literature.

RBC Transfusion Practice in Pediatric Extracorporeal Membrane Oxygenation Support

OBJECTIVES

To determine RBC transfusion practice and relationships between RBC transfusion volume and mortality in infants and children treated with extracorporeal membrane oxygenation.

DESIGN

Secondary analysis of a multicenter prospective observational study.

SETTING

Eight pediatric institutions within the Eunice Kennedy Shriver National Institute of Child Health and Human Development's Collaborative Pediatric Critical Care Research Network.

PATIENTS

Patients age less than 19 years old treated with extracorporeal membrane oxygenation at a participating center.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Clinical data and target hemoglobin or hematocrit values (if set) were recorded daily by trained bedside extracorporeal membrane oxygenation specialists and research coordinators. Laboratory values, including hemoglobin and hematocrit, were recorded daily using the value obtained closest to 8:00 AM. RBC transfusion was recorded as total daily volume in mL/kg. Multivariable logistic regression was used to determine the relationship between RBC transfusion volume and hospital mortality, accounting for potential confounders. Average goal hematocrits varied across the cohort with a range of 27.5-41.3%. Overall, actual average daily hematocrit was 36.8%, and average RBC transfusion volume was 29.4 mL/kg/d (17.4-49.7 mL/kg/d) on extracorporeal membrane oxygenation. On multivariable analysis, each additional 10 mL/kg/d of RBC transfusion volume was independently associated with a 9% increase in odds of hospital mortality (adjusted odds ratio, 1.09 [1.02-1.16]; p = 0.009).

CONCLUSIONS

In this multicenter cohort of pediatric extracorporeal membrane oxygenation patients, daily hematocrit levels were maintained at normal or near-normal values and RBC transfusion burden was high. RBC transfusion volume was independently associated with odds of mortality. Future clinical studies to identify optimum RBC transfusion thresholds for pediatric extracorporeal membrane oxygenation are urgently needed.

Indications for red cell transfusions in pediatric patients

Red cell transfusions are amongst the most common therapeutic procedures in seriously ill children, particularly in the inpatient setting. This is despite the fact that there is no evidence base for most clinical settings, with the exception of patients with hemoglobinopathies, particularly thalassemia and sickle cell anemia. Obviously exsanguinating hemorrhage and life threatening anemia are urgent indications for which no other therapeutic approach is currently available. Most transfusions are, however, given prophylactically to prevent the complications of hypoxia or hemodynamic stability, based upon expert opinion and a faith in the oxygen carrying capacity and beneficial hemodynamic properties of transfused red cells. The question confronting current day pediatric practice is to what extent transfused red cells prevent adverse events, other than in thalassemia and sickle cell anemia, as opposed to causing them. Do transfusions of red cells prevent organ failure, stroke, etc. or not? There is epidemiologic evidence in the adult randomized trial literature that liberal red cell transfusion likely causes more such adverse events than it prevents. The relevance of such studies to children, particularly neonates, is uncertain. Randomized trials in critically ill neonates have yielded little to no evidence that liberal red cell transfusion is beneficial, but the data are not definitive. In critically ill older children the data suggest there is no benefit to liberal red cell transfusion, but the indications for red cell transfusion are uncertain. Most practitioners would agree that combining laboratory data such hemoglobin/hematocrit with clinical indications for transfusions (evidence of end organ hypoxia such as tachycardia, shortness of breath, etc.) is the only viable strategy at present, until more definitive randomized trial data are available.

Hemoglobin Levels Across the Pediatric Critical Care Spectrum: A Point Prevalence Study

OBJECTIVES

To determine the prevailing hemoglobin levels in PICU patients, and any potential correlates.

DESIGN

Post hoc analysis of prospective multicenter observational data.

SETTINGS

Fifty-nine PICUs in seven countries.

PATIENTS

PICU patients on four specific days in 2012.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients' hemoglobin and other clinical and institutional data. Two thousand three hundred eighty-nine patients with median age of 1.9 years (interquartile range, 0.3-9.8 yr), weight 11.5 kg (interquartile range, 5.4-29.6 kg), and preceding PICU stay of 4.0 days (interquartile range, 1.0-13.0 d). Their median hemoglobin was 11.0 g/dL (interquartile range, 9.6-12.5 g/dL). The prevalence of transfusion in the 24 hours preceding data collection was 14.2%. Neonates had the highest hemoglobin at 13.1 g/dL (interquartile range, 11.2-15.0 g/dL) compared with other age groups (p < 0.001). The percentage of 31.3 of the patients had hemoglobin of greater than or equal to 12 g/dL, and 1.1% had hemoglobin of less than 7 g/dL. Blacks had lower median hemoglobin (10.5; interquartile range, 9.3-12.1 g/dL) compared with whites (median, 11.1; interquartile range, 9.0-12.6; p < 0.001). Patients in Spain and Portugal had the highest median hemoglobin (11.4; interquartile range, 10.0-12.6) compared with other regions outside of the United States (p < 0.001), and the highest proportion (31.3%) of transfused patients compared with all regions (p < 0.001). Patients in cardiac PICUs had higher median hemoglobin than those in mixed PICUs or noncardiac PICUs (12.3, 11.0, and 10.6 g/dL, respectively; p < 0.001). Cyanotic heart disease patients had the highest median hemoglobin (12.6 g/dL; interquartile range, 11.1-14.5). Multivariable regression analysis within diagnosis groups revealed that hemoglobin levels were significantly associated with the geographic location and history of complex cardiac disease in most of the models. In children with cancer, none of the variables tested correlated with patients' hemoglobin levels.

CONCLUSIONS

Patients' hemoglobin levels correlated with demographics like age, race, geographic location, and cardiac disease, but none found in cancer patients. Future investigations should account for the effects of these variables.

Cerebral Oxygen Metabolism Before and After RBC Transfusion in Infants Following Major Surgical Procedures

OBJECTIVE

Although infants following major surgery frequently require RBC transfusions, there is still controversy concerning the best definition for requirement of transfusion in the individual patient. The aim of this study was to determine the impact of RBC transfusion on cerebral oxygen metabolism in noncardiac and cardiac postsurgical infants.

DESIGN

Prospective observational cohort study.

SETTING

Pediatric critical care unit of a tertiary referral center.

PATIENTS

Fifty-eight infants (15 after pediatric surgery and 43 after cardiac surgery) with anemia requiring RBC transfusion were included.

INTERVENTIONS

RBC transfusion.

MEASUREMENTS AND MAIN RESULTS

We measured noninvasively regional cerebral oxygen saturation and microperfusion (relative cerebral blood flow) using tissue spectrometry and laser Doppler flowmetry before and after RBC transfusion. Cerebral fractional tissue oxygen extraction and approximated cerebral metabolic rate of oxygen were calculated. Fifty-eight RBC transfusions in 58 patients were monitored (15 after general surgery, 24 after cardiac surgery resulting in acyanotic biventricular physiology and 19 in functionally univentricular hearts including hypoplastic left heart following neonatal palliation). The posttransfusion hemoglobin concentrations increased significantly (9.7 g/dL vs 12.8 g/dL; 9.7 g/dL vs 13.8 g/dL; 13.1 g/dL vs 15.6 g/dL; p < 0.001, respectively). Posttransfusion cerebral oxygen saturation was significantly higher than pretransfusion (61% [51-78] vs 72% [59-89]; p < 0.001; 58% [35-77] vs 71% [57-88]; p < 0.001; 51% [37-61] vs 58% [42-73]; p = 0.007). Cerebral fractional tissue oxygen extraction decreased posttransfusion significantly 0.37 (0.16-0.47) and 0.27 (0.07-039), p = 0.002; 0.40 (0.2-0.62) vs 0.26 (0.11-0.57), p = 0.001; 0.42 (0.23-0.52) vs 0.32 (0.1-0.42), p = 0.017. Cerebral blood flow and approximated cerebral metabolic rate of oxygen showed no significant change during the observation period. The increase in cerebral oxygen saturation and the decrease in cerebral fractional tissue oxygen extraction were most pronounced in patients after cardiac surgery with a pretransfusion cerebral fractional tissue oxygen extraction greater than or equal to 0.4.

CONCLUSION

Following RBC transfusion, cerebral oxygen saturation increases and cerebral fractional tissue oxygen extraction decreases. The data suggest that cerebral oxygenation in postoperative infants with cerebral fractional tissue oxygen extraction greater than or equal to 0.4 may be at risk in instable hemodynamic or respiratory situations.

Comprehensive blood conservation program in a new congenital cardiac surgical program allows bloodless surgery for the Jehovah Witness and a reduction for all patients

BACKGROUND

Cardiac surgery on Jehovah's Witnesses (JW) can be challenging, given the desire to avoid blood products. Establishment of a blood conservation program involving the pre-, intra- and post-operative stages for all patients may lead to a minimized need for blood transfusion in all patients.

METHODS

Pre-operatively, all JW patients were treated with high dose erythropoietin 500 IU/kg twice a week. JW patients were compared to matching non-JW patients from the congenital cardiac database, two per JW to serve as control. Blood use, ventilation time, bypass time, pre-operative hematocrit, first in intensive care unit (ICU) and at discharge and 24 hour chest drainage were compared. Pre-operative huddle, operating room huddle and post-operative bedside handoff were done with the congenital cardiac surgeon, perfusionist, anesthesiologist and intensive care team in all patients for goal alignment.

RESULTS

Five JW patients (mean weight 24.4 ± 25.0 Kg, range 6.3 - 60 Kg) were compared to 10 non-JW patients (weight 22.0 ± 22.8 Kg, range 6.2 - 67.8 Kg). There was no difference in bypass, cross-clamp, time to extubation (0.8 vs. 2.1 hours), peak inotrope score (2.0 vs. 2.3) or chest drainage. No JW patient received a blood product compared to 40% of non-JW. The pre-operative hematocrit (Hct) was statistically greater for the JW patients (46.1 ± 3.3% vs. 36.3 ± 4.7%, p<0.001) and both ICU and discharge Hct were higher for the JW (37 ± 1.8% vs 32.4 ± 8.0% and 41 ± 8.1% vs 34.8 ± 7.9%), but did not reach statistical significance. All patients had similar blood draws during the hospitalization (JW x 18 mL/admission vs non-JW 20 mL/admission).

CONCLUSION

The continuous application and development of blood conservation techniques across the continuum of care allowed bloodless surgery for JW and non-JW patients alike. Blood conservation is a team sport and to make significant strides requires participation and input by all care providers.

Hemoglobin Level at Stage 1 Discharge has No Impact on Inter-stage Growth and Stability in Single Ventricle Infants

Hemoglobin levels (Hgb) of infants with a single ventricle (SV) are traditionally maintained high to maximize oxygen-carrying capacity during stage 1 palliation (S1P), stage 2 palliation (S2P), and between stages (IS). A single-center observational cohort study was performed to determine if red blood cell transfusion during the convalescent phase of the S1P (late S1P transfusion) to achieve higher Hgb is associated with benefits during the IS including improved growth and decreased acute medical events. 137 infants <1 year with SV with SIP undergoing care from January 2008 to June 2015 were retrospectively evaluated. 78 (57%) infants received a late S1P transfusion. Median Hgb at S1P discharge was 15.9 g/dL (IQR 14.7-17.1) and median Hgb S2P at admission was 15.3 g/dL (IQR 14-16.3). Median daily weight gain was 22 g/day during IS (IQR 17-26) and median daily length gain was 0.09 cm (IQR 0.06-0.11). Hgb at SIP discharge was not associated with IS growth or fewer IS acute events. However, late S1P transfusions were associated with illness severity at S1P and more complicated S1P care. Our data suggest that SV infants after S1P, who are steadily recovering, do not benefit from late transfusion to raise their hemoglobin level at discharge.

Blood conservation pediatric cardiac surgery in all ages and complexity levels

AIM

To demonstrate the feasibility of blood conservation methods and practice across all ages and risk categories in congenital cardiac surgery.

METHODS

We retrospectively analyzed a collected database of 356 patients who underwent cardiac surgery using cardiopulmonary bypass (CPB) from 2010-2015. The patients were grouped into blood conservation (n = 138) and non-conservation (n = 218) groups and sub-grouped based on their ages and procedural complexity scores.

RESULTS

There were no statistical differences in gender, weight, pre-operative and pre-CPB hematocrit levels in both groups. Despite equivalent hematocrit levels during and after CPB for both groups, there was significantly less operative homologous blood utilized in blood conservation group across all ages and complexity levels.

CONCLUSION

Blood conservation surgery can be performed in congenital patients needing cardiac surgery in all age groups and complexity categories. The above findings in addition to attendant risks and side effects of blood transfusion and the rising cost of safer blood products justify blood conservation in congenital cardiac surgery.

Strategies for blood conservation in pediatric cardiac surgery

Cardiac surgery accounts for the majority of blood transfusions in a hospital. Blood transfusion has been associated with complications and major adverse events after cardiac surgery. Compared to adults it is more difficult to avoid blood transfusion in children after cardiac surgery. This article takes into account the challenges and emphasizes on the various strategies that could be implemented, to conserve blood during pediatric cardiac surgery.

The intensive care medicine clinical research agenda in paediatrics

BACKGROUND

Intensive Care Medicine set us the task of outlining a global clinical research agenda for paediatric intensive care (PIC). In line with the clinical focus of this journal, we have limited this to research that may directly influence patient care.

METHODS

Clinician researchers from PIC research networks of varying degrees of formality from around the world were invited to answer two main questions: (1) What have been the major recent advances in paediatric critical care research? (2) What are the top 10 studies for the next 10 years?

RESULTS

(1) Inclusive databases are well established in many countries. These registries allow detailed observational studies and feasibility testing of clinical trial protocols. Recent trials are larger and more valuable, and (2) most common interventions in PIC are not evidenced-based. Clinical studies for the next 10 years should address this deficit, including: ventilation techniques and interfaces; fluid, transfusion and feeding strategies; optimal targets for vital signs; multiple organ failure definitions, mechanisms and treatments; trauma, prevention and treatment; improving safety; comfort of the patient and their family; appropriate care in the face of medical complexity; defining post-PICU outcomes; and improving knowledge generation and adoption, with novel trial design and implementation strategies. The group specifically highlighted the need for research in resource-limited environments wherein mortality remains often tenfold higher than in well-resourced settings.

CONCLUSION

Paediatric intensive care research has never been healthier, but many gaps in knowledge remain. We need to close these urgently. The impact of new knowledge will be greatest in resource-limited environments.

Restrictive versus liberal red blood cell transfusion strategies for people with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without haematopoietic stem cell support

BACKGROUND

Many people diagnosed with haematological malignancies experience anaemia, and red blood cell (RBC) transfusion plays an essential supportive role in their management. Different strategies have been developed for RBC transfusions. A restrictive transfusion strategy seeks to maintain a lower haemoglobin level (usually between 70 g/L to 90 g/L) with a trigger for transfusion when the haemoglobin drops below 70 g/L), whereas a liberal transfusion strategy aims to maintain a higher haemoglobin (usually between 100 g/L to 120 g/L, with a threshold for transfusion when haemoglobin drops below 100 g/L). In people undergoing surgery or who have been admitted to intensive care a restrictive transfusion strategy has been shown to be safe and in some cases safer than a liberal transfusion strategy. However, it is not known whether it is safe in people with haematological malignancies.

OBJECTIVES

To determine the efficacy and safety of restrictive versus liberal RBC transfusion strategies for people diagnosed with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without a haematopoietic stem cell transplant (HSCT).

SEARCH METHODS

We searched for randomised controlled trials (RCTs) and non-randomised trials (NRS) in MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1982), Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 6), and 10 other databases (including four trial registries) to 15 June 2016. We also searched grey literature and contacted experts in transfusion for additional trials. There was no restriction on language, date or publication status.

SELECTION CRITERIA

We included RCTs and prospective NRS that evaluated a restrictive compared with a liberal RBC transfusion strategy in children or adults with malignant haematological disorders or undergoing HSCT.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We identified six studies eligible for inclusion in this review; five RCTs and one NRS. Three completed RCTs (156 participants), one completed NRS (84 participants), and two ongoing RCTs. We identified one additional RCT awaiting classification. The completed studies were conducted between 1997 and 2015 and had a mean follow-up from 31 days to 2 years. One study included children receiving a HSCT (six participants), the other three studies only included adults: 218 participants with acute leukaemia receiving chemotherapy, and 16 with a haematological malignancy receiving a HSCT. The restrictive strategies varied from 70 g/L to 90 g/L. The liberal strategies also varied from 80 g/L to 120 g/L.Based on the GRADE rating methodology the overall quality of the included studies was very low to low across different outcomes. None of the included studies were free from bias for all 'Risk of bias' domains. One of the three RCTs was discontinued early for safety concerns after recruiting only six children, all three participants in the liberal group developed veno-occlusive disease (VOD). Evidence from RCTsA restrictive RBC transfusion policy may make little or no difference to: the number of participants who died within 100 days (two trials, 95 participants (RR: 0.25, 95% CI 0.02 to 2.69, low-quality evidence); the number of participants who experienced any bleeding (two studies, 149 participants; RR:0.93, 95% CI 0.73 to 1.18, low-quality evidence), or clinically significant bleeding (two studies, 149 participants, RR: 1.03, 95% CI 0.75 to 1.43, low-quality evidence); the number of participants who required RBC transfusions (three trials; 155 participants: RR: 0.97, 95% CI 0.90 to 1.05, low-quality evidence); or the length of hospital stay (restrictive median 35.5 days (interquartile range (IQR): 31.2 to 43.8); liberal 36 days (IQR: 29.2 to 44), low-quality evidence).We are uncertain whether the restrictive RBC transfusion strategy: decreases quality of life (one trial, 89 participants, fatigue score: restrictive median 4.8 (IQR 4 to 5.2); liberal median 4.5 (IQR 3.6 to 5) (very low-quality evidence); or reduces the risk of developing any serious infection (one study, 89 participants, RR: 1.23, 95% CI 0.74 to 2.04, very low-quality evidence).A restrictive RBC transfusion policy may reduce the number of RBC transfusions per participant (two trials; 95 participants; mean difference (MD) -3.58, 95% CI -5.66 to -1.49, low-quality evidence). Evidence from NRSWe are uncertain whether the restrictive RBC transfusion strategy: reduces the risk of death within 100 days (one study, 84 participants, restrictive 1 death; liberal 1 death; very low-quality evidence); decreases the risk of clinically significant bleeding (one study, 84 participants, restrictive 3; liberal 8; very low-quality evidence); or decreases the number of RBC transfusions (adjusted for age, sex and acute myeloid leukaemia type geometric mean 1.25; 95% CI 1.07 to 1.47 - data analysis performed by the study authors)No NRS were found that looked at: quality of life; number of participants with any bleeding; serious infection; or length of hospital stay.No studies were found that looked at: adverse transfusion reactions; arterial or venous thromboembolic events; length of intensive care admission; or readmission to hospital.

AUTHORS' CONCLUSIONS

Findings from this review were based on four studies and 240 participants.There is low-quality evidence that a restrictive RBC transfusion policy reduces the number of RBC transfusions per participant. There is low-quality evidence that a restrictive RBC transfusion policy has little or no effect on: mortality at 30 to 100 days, bleeding, or hospital stay. This evidence is mainly based on adults with acute leukaemia who are having chemotherapy. Although, the two ongoing studies (530 participants) are due to be completed by January 2018 and will provide additional information for adults with haematological malignancies, we will not be able to answer this review's primary outcome. If we assume a mortality rate of 3% within 100 days we would need 1492 participants to have a 80% chance of detecting, as significant at the 5% level, an increase in all-cause mortality from 3% to 6%. Further RCTs are required in children.