Anemia, blood loss, and blood transfusions in North American children in the intensive care unit

Bleeding Assessment Scale in Critically Ill Children (BASIC): Physician-Driven Diagnostic Criteria for Bleeding Severity

OBJECTIVE

Although bleeding frequently occurs in critical illness, no published definition to date describes the severity of bleeding accurately in critically ill children. We sought to develop diagnostic criteria for bleeding severity in critically ill children.

DESIGN

Delphi consensus process of multidisciplinary experts in bleeding/hemostasis in critically ill children, followed by prospective cohort study to test internal validity.

SETTING

PICU.

PATIENTS

Children at risk of bleeding in PICUs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Twenty-four physicians worldwide (10 on a steering committee and 14 on an expert committee) from disciplines related to bleeding participated in development of a definition for clinically relevant bleeding. A provisional definition was created from 35 descriptors of bleeding. Using a modified online Delphi process and conference calls, the final definition resulted after seven rounds of voting. The Bleeding Assessment Scale in Critically Ill Children definition categorizes bleeding into severe, moderate, and minimal, using organ dysfunction, proportional changes in vital signs, anemia, and quantifiable bleeding. The criteria do not include treatments such as red cell transfusion or surgical interventions performed in response to the bleed. The definition was prospectively applied to 40 critically ill children with 46 distinct bleeding episodes. The kappa statistic between the two observers was 0.74 (95% CI, 0.57-0.91) representing substantial inter-rater reliability.

CONCLUSIONS

The Bleeding Assessment Scale in Critically Ill Children definition of clinically relevant bleeding severity is the first physician-driven definition applicable for bleeding in critically ill children derived via international expert consensus. The Bleeding Assessment Scale in Critically Ill Children definition includes clear criteria for bleeding severity in critically ill children. We anticipate that it will facilitate clinical communication among pediatric intensivists pertaining to bleeding and serve in the design of future epidemiologic studies if it is validated with patient outcomes.

Quantifiable Bleeding in Children Supported by Extracorporeal Membrane Oxygenation and Outcome

OBJECTIVES

To evaluate the association between bleeding from chest tubes and clinical outcomes in children supported by extracorporeal membrane oxygenation.

DESIGN

Secondary analysis of a large observational cohort 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

Critically ill children supported by extracorporeal membrane oxygenation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Daily chest tube bleeding, results from hemostatic assays, transfusion volumes, 90-day PICU-free days, and mortality were collected prospectively by trained bedside extracorporeal membrane oxygenation specialists and research coordinators. Extracorporeal membrane oxygenation was employed in the care of 514 consecutive patients. Sixty percent of patients had at least one episode of chest tube bleeding (median chest tube blood volume over the entire extracorporeal membrane oxygenation course was 123 mL/kg [interquartile range, 47-319 mL/kg]). Twenty-six percent had at least 1 day of bleeding from the chest tube greater than 100 mL/kg/d. The number of days with chest tube bleeding greater than 60 mL/kg/d was independently associated with increased in-hospital mortality (adjusted odds ratio, 1.43; 95% CI, 1.05-1.97; p = 0.02) and decreased PICU-free days (beta coefficient, -4.2; 95% CI, -7.7 to -0.6; p = 0.02). The total amount of bleeding from chest tube were independently associated with increased mortality (per mL/kg/extracorporeal membrane oxygenation run; adjusted odds ratio, 1.002; 95% CI, 1.000-1.003; p = 0.04). Fibrinogen, weight, indication for extracorporeal membrane oxygenation, and need for hemodialysis were independently associated with chest tube bleeding, whereas platelet count, coagulation tests, heparin dose, and thrombotic events were not.

CONCLUSIONS

In children supported by extracorporeal membrane oxygenation, chest tube bleeding above 60 mL/kg/d was independently associated with worse clinical outcome. Low fibrinogen was independently associated with chest tube bleeding, whereas platelet count and hemostatic tests were not. Further research is needed to evaluate if interventions to prevent or stop chest tube bleeding influence the clinical outcome.

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.

Severe neonatal anemia increases intestinal permeability by disrupting epithelial adherens junctions

Anemia is a frequent diagnosis in critically ill infants, but the clinical implications of severe anemia in these patients remain unclear. In this study, we examined preweaned mice to investigate the effects of severe anemia during early infancy on gut mucosal permeability. C57BL/6 mice were subjected to timed phlebotomy between postnatal days (P) 2-10 to induce severe anemia (hematocrits 20%-24%), and intestinal permeability was tracked longitudinally between P10 and P20 as intestine-to-plasma translocation of enteral macromolecules and bacterial translocation. Epithelial junctions were evaluated by electron microscopy, polymerase chain reactions, immunohistochemistry, and/or enzyme immunoassays on intestinal tissues, Caco-2 intestinal epithelial-like cells, and colonic organoids. Preweaned mouse pups showed an age-related susceptibility to severe anemia, with increased intestinal permeability to enteral macromolecules (dextran, ovalbumin, β-lactoglobulin) and luminal bacteria. Electron micrographs showed increased paracellular permeability and ultrastructural abnormalities of the adherens junctions. These findings were explained by the loss of E-cadherin in epithelial cells, which was caused by destabilization of the E-cadherin (Cdh1) mRNA because of microRNA let-7e-5p binding to the 3'-untranslated region. Severe anemia resulted in a disproportionate and persistent increase in intestinal permeability in preweaned mice because of the disruption of epithelial adherens junctions. These changes are mediated via microRNA let-7e-mediated depletion of Cdh1 mRNA.NEW & NOTEWORTHY This research article shows that newborn infants with severe anemia show an age-related susceptibility to developing increased intestinal permeability to ingested macromolecules. This abnormal permeability develops because of abnormalities in intestinal epithelial junctions caused by a deficiency of the molecule E-cadherin in epithelial cells. The deficiency of E-cadherin is caused by destabilization of its mRNA precursor because of increased expression and binding of another molecule, the microRNA let-7e-5p, to the E-cadherin mRNA.

Digital Microfluidic Platform to Maximize Diagnostic Tests with Low Sample Volumes from Newborns and Pediatric Patients

"Children are not tiny adults" is an adage commonly used in pediatrics to emphasize the fact that children often have different physiological responses to sickness and trauma compared to adults. However, despite widespread acceptance of this concept, diagnostic blood testing is an excellent example of clinical care that is not yet customized to the needs of children, especially newborns. Cumulative blood loss resulting from clinical testing does not typically impact critically ill adult patients, but can quickly escalate in children, leading to iatrogenic anemia and related comorbidities. Moreover, the tests prioritized for rapid, near-patient testing in adults are not always the most clinically relevant tests for children or newborns. This report describes the development of a digital microfluidic testing platform and associated clinical assays purposely curated to address current shortcomings in pediatric laboratory testing by using microliter volumes (<50 µL) of samples. The automated platform consists of a small instrument and single-use cartridges, which contain all reagents necessary to prepare the sample and perform the assay. Electrowetting technology is used to precisely manipulate nanoliter-sized droplets of samples and reagents inside the cartridge. To date, we have automated three disparate types of assays (biochemical assays, immunoassays, and molecular assays) on the platform and have developed over two dozen unique tests, each with important clinical application to newborns and pediatric patients. Cell lysis, plasma preparation, magnetic bead washing, thermocycling, incubation, and many other essential functions were all performed on the cartridge without any user intervention. The resulting assays demonstrate performance comparable to standard clinical laboratory assays and are economical due to the reduced hands-on effort required for each assay and lower overall reagent consumption. These capabilities allow a wide range of assays to be run simultaneously on the same cartridge using significantly reduced sample volumes with results in minutes.

Safe phlebotomy reduction in stable pediatric liver and spleen injuries

PURPOSE

Pediatric blunt solid organ injury management based on hemodynamic monitoring rather than grade may safely reduce resource expenditure and improve outcomes. Previously we have reported a retrospectively validated management algorithm for pediatric liver and spleen injuries which monitors hemodynamics without use of routine phlebotomy. We hypothesize that stable blunt pediatric isolated splenic/liver injuries can be managed safely using a protocol reliant on vital signs and not repeat hemoglobin levels.

METHODS

A prospective multi-institutional study was performed at three pediatric trauma centers. All pediatric patients from 07/2016-12/2017 diagnosed with liver or splenic injuries were identified. If appropriate for the protocol, only a baseline hemoglobin was obtained unless hemodynamic instability as defined in an age-appropriate fashion was determined by treating physician discretion. Descriptive statistics were conducted.

RESULTS

One hundred four patients were identified of which 38 were excluded from the protocol. There was a significant difference in abnormal shock index, pediatric age-adjusted (SIPA) values, hematocrit, and percentage of patients with hemoglobin less than 10 between the excluded and included patients. Of the 66 patients managed on the protocol, four patients had to be removed, two each on day one and day two. Of those four patients, only one required intervention. There were no mortalities.

CONCLUSION

A phlebotomy limiting protocol may be a safe option for stable pediatric splenic and liver injuries cared for in a pediatric trauma center with the resources for rapid intervention should the need arise. The differences in groups highlight the importance of utilizing this protocol in the correct patient population. Reduced phlebotomy offers the potential for reduced resource expenditure without any evidence of increased morbidity or mortality.

LEVEL OF EVIDENCE

Level IV.

Transfusion in children with acute respiratory distress syndrome

Transfusion is a frequent treatment in pediatric patients with acute respiratory distress syndrome (PARDS) although evidence to support transfusion decision-making is lacking. The purpose of this review is to review the current state of knowledge on the issue of transfusion in children with PARDS and to detail the possible beneficial effects and potential deleterious impacts of transfusion in this patient population. Based on the current literature and recent guidelines, a restrictive red blood cell (RBC) transfusion strategy (avoidance of transfusion when the haemoglobin level is above 7 g/dL) is indicated in stable patients without severe PARDS, as these were excluded from the large trials. In children with severe PARDS, further research is needed to determine if factors other than the haemoglobin level might guide RBC transfusion decision-making by better characterizing the presence of low oxygen delivery (DO₂). Additionally, appropriate indications for prophylactic transfusion of hemostatic products (plasma or platelets) in children with PARDS are lacking.

Association between anemia and postoperative complications in infants undergoing pyloromyotomy

BACKGROUND

Although preoperative anemia has been suggested to predict postsurgical morbidity and mortality among infants <1 year of age, the data were drawn from heterogeneous patient cohorts including severely ill infants undergoing complex, high-risk procedures. We aimed to determine whether untreated preoperative anemia was associated with increased risk of postoperative complications in infants <1 year of age who underwent pyloromyotomy, a common and relatively simple surgery.

METHODS

Infants <1 year of age undergoing pyloromyotomy were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program-Pediatric database. Preoperative anemia was defined as a hematocrit ≤40% for infants 0-30 days of age and ≤30% for infants more than 30 days of age. Patients who received pre- or postoperative blood transfusions were excluded.

RESULTS

We identified 2948 patients who met our inclusion criteria, of whom 843 were anemic (29%). The overall rate of complications in this cohort was 6%. The most common postoperative complications were readmission (97 cases), surgical site infection (43), reoperation (39), prolonged hospital stay (24), urinary tract infection (3), 30-day mortality (3) and cardiac arrest (2). We found no differences in the incidence of complications in anemic versus nonanemic patients on bivariate analysis or multivariable logistic regression (adjusted odds ratio = 1.2; 95% confidence interval: 0.8-1.7; P = 0.319).

CONCLUSIONS

In relatively healthy infants undergoing pyloromyotomy, untreated preoperative anemia was not associated with postoperative compilations and should not be considered a significant risk factor. Level of evidence III.

The Postinjury Inflammatory State and the Bone Marrow Response to Anemia

RATIONALE

The pathophysiology of persistent injury-associated anemia is incompletely understood, and human data are sparse.

OBJECTIVES

To characterize persistent injury-associated anemia among critically ill trauma patients with the hypothesis that severe trauma would be associated with neuroendocrine activation, erythropoietin dysfunction, iron dysregulation, and decreased erythropoiesis.

METHODS

A translational prospective observational cohort study comparing severely injured, blunt trauma patients who had operative fixation of a hip or femur fracture (n = 17) with elective hip repair patients (n = 22). Bone marrow and plasma obtained at the index operation were assessed for circulating catecholamines, systemic inflammation, erythropoietin, iron trafficking pathways, and erythroid progenitor growth. Bone marrow was also obtained from healthy donors from a commercial source (n = 8).

MEASUREMENTS AND MAIN RESULTS

During admission, trauma patients had a median of 625 ml operative blood loss and 5 units of red blood cell transfusions, and Hb decreased from 10.5 to 9.3 g/dl. Compared with hip repair, trauma patients had higher median plasma norepinephrine (21.9 vs. 8.9 ng/ml) and hepcidin (56.3 vs. 12.2 ng/ml) concentrations (both P < 0.05). Bone marrow erythropoietin and erythropoietin receptor expression were significantly increased among patients undergoing hip repair (23% and 14% increases, respectively; both P < 0.05), but not in trauma patients (3% and 5% increases, respectively), compared with healthy control subjects. Trauma patients had lower bone marrow transferrin receptor expression than did hip repair patients (57% decrease; P < 0.05). Erythroid progenitor growth was decreased in trauma patients (39.0 colonies per plate; P < 0.05) compared with those with hip repair (57.0 colonies per plate; P < 0.05 compared with healthy control subjects) and healthy control subjects (66.5 colonies per plate).

CONCLUSIONS

Severe blunt trauma was associated with neuroendocrine activation, erythropoietin dysfunction, iron dysregulation, erythroid progenitor growth suppression, and persistent injury-associated anemia. Clinical trial registered with www.clinicaltrials.gov (NCT 02577731).

Anemia at Discharge From the PICU: A Bicenter Descriptive Study

OBJECTIVE

To determine the prevalence and risk markers of anemia at PICU discharge.

DESIGN

Bicenter retrospective cohort study.

SETTING

Two multidisciplinary French PICUs.

PATIENTS

All children admitted during a 5-year period, staying in the PICU for at least 2 days, and for whom a hemoglobin was available at PICU discharge.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patient, admission, and PICU stay characteristics were retrospectively collected in the electronic medical records of each participating PICU. Anemia was defined according to the World Health Organization criteria. Among the 3,170 patients included for analysis, 1,868 (58.9%) were anemic at discharge from PICU. The proportion of anemic children differed between age categories, whereas the median hemoglobin level did not exhibit significant variations according to age. After multivariate adjustment, anemia at PICU admission was the strongest predictor of anemia at PICU discharge, and the strength of this association varied according to age (interaction). Children anemic at PICU admission had a reduced risk of anemia at PICU discharge if transfused with RBCs during the PICU stay, if less than 6 months old, or if creatinine level at PICU admission was low. Children not anemic at PICU admission had an increased risk of anemia at PICU discharge if they were thrombocytopenic at PICU admission, if they had higher C-reactive protein levels, and if they received plasma transfusion, inotropic/vasopressor support, or mechanical ventilation during the PICU stay.

CONCLUSIONS

Anemia is frequent after pediatric critical illness. Anemia status at PICU admission defines different subgroups of critically ill children with specific prevalence and risk markers of anemia at PICU discharge. Further studies are required to confirm our results, to better define anemia during pediatric critical illness, and to highlight the causes of post-PICU stay anemia, its course, and its association with post-PICU outcomes.

Blood manufacturing methods affect red blood cell product characteristics and immunomodulatory activity

Transfusion of red cell concentrates (RCCs) is associated with increased risk of adverse outcomes that may be affected by different blood manufacturing methods and the presence of extracellular vesicles (EVs). We investigated the effect of different manufacturing methods on hemolysis, residual cells, cell-derived EVs, and immunomodulatory effects on monocyte activity. Thirty-two RCC units produced using whole blood filtration (WBF), red cell filtration (RCF), apheresis-derived (AD), and whole blood-derived (WBD) methods were examined (n = 8 per method). Residual platelet and white blood cells (WBCs) and the concentration, cell of origin, and characterization of EVs in RCC supernatants were assessed in fresh and stored supernatants. Immunomodulatory activity of RCC supernatants was assessed by quantifying monocyte cytokine production capacity in an in vitro transfusion model. RCF units yielded the lowest number of platelet and WBC-derived EVs, whereas the highest number of platelet EVs was in AD (day 5) and in WBD (day 42). The number of small EVs (<200 nm) was greater than large EVs (≥200 nm) in all tested supernatants, and the highest level of small EVs were in AD units. Immunomodulatory activity was mixed, with evidence of both inflammatory and immunosuppressive effects. Monocytes produced more inflammatory interleukin-8 after exposure to fresh WBF or expired WBD supernatants. Exposure to supernatants from AD and WBD RCC suppressed monocyte lipopolysaccharide-induced cytokine production. Manufacturing methods significantly affect RCC unit EV characteristics and are associated with an immunomodulatory effect of RCC supernatants, which may affect the quality and safety of RCCs.

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.

Transfusion Management in Pediatric Oncology Patients

Pediatric oncology patients will likely require numerous transfusions of blood products, including red blood cell, platelet, and plasma transfusions, during the course of their treatment. Although strong evidence-based guidelines for these products in this patient population do not exist, given the morbidities associated with the receipt of blood products, practitioners should attempt to use restrictive transfusion strategies.

What are the non-cardiac prognostic factors affecting mortality in neonates with aortopulmonary shunt

Background/aim: Systemic to pulmonary shunts (SPS) have proven to be highly effective for the palliation of neonates with cyanotic congenital heart disease. Mortality after SPS surgery in neonates has multifactorial basis. We aimed to investigate the clinical results of the SPS in relation to the underlying cardiac disease and to identify the risk factors contributing to an adverse outcome.Material and method: All neonates who underwent first shunt insertion for cyanotic congenital heart disease during the study period from 1 January 2014 to 31 December 2017 were included. A retrospective review of patient records was done. Patients were grouped into two different categories: survived with or without any reintervention and death before or after any reintervention till discharge.Result: During the study period, 47 patients underwent SPS shunt placement. Patients who survived with or without any reintervention were in Group 1 and patients who died before or after any reintervention till discharge were in Group 2. Preoperative epinephrine requirement and mechanical ventilation and postoperative erythrocyte transfusion need were statistically significant.Conclusion: Although primary cardiac pathology is the most important prognostic factor, some other preoperative and postoperative factors like preoperative epinephrine requirement, and postoperative erythrocyte transfusion might also affect the prognosis. As there are very few centers in the region that specialize in pediatric cardiac surgery, a multicenter approach will be helpful in reaching reliable conclusions.

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.

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.

Restrictive guideline for red blood cell transfusions in preterm neonates: effect of a protocol change

OBJECTIVE

To evaluate red blood cell (RBC) transfusion practices in preterm neonates before and after protocol change.

METHODS

All preterm neonates (<32 weeks of gestation) admitted between 2008 and 2017 at our neonatal intensive care unit were included in this retrospective study. Since 2014, a more restrictive transfusion guideline was implemented in our unit. We compared transfusion practices before and after this guideline change. Primary outcome was the number of transfusions per neonate and the percentage of neonates receiving a blood transfusion. Secondary outcomes were neonatal morbidities and mortality during admission.

RESULTS

The percentage of preterm neonates requiring a blood transfusion was 37·5% (405/1079) before and 32·7% (165/505) after the protocol change (P = 0·040). The mean number of transfusions given to each transfused neonate decreased from 2·93 (standard deviation (SD) ± 2·26) to 2·20 (SD ±1·29) (P = 0·007). We observed no association between changes in transfusion practices and neonatal outcome.

CONCLUSION

The use of a more restrictive transfusion guideline leads to a reduction in red blood cell transfusions in preterm neonates, without evidence of an increase in mortality or short-term morbidity.

Methods in the design and implementation of the Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE) clinical trial

Background

Few papers discuss the pragmatics of conducting large, cluster randomized clinical trials. Here we describe the sequential steps taken to develop methods to implement the Randomized Evaluation of Sedation Titration for Respiratory Failure (RESTORE) trial that tested the effect of a nurse-implemented, goal-directed, comfort algorithm on clinical outcomes in pediatric patients with acute respiratory failure.

Methods

After development in a single institution, the RESTORE intervention was pilot-tested in two pediatric intensive care units (PICUs) to evaluate safety and feasibility. After the pilot, the RESTORE intervention was simplified to enhance reproducibility across multiple PICUs. The final RESTORE trial was developed as a cluster randomized clinical trial where the unit of randomization was the PICU, stratified by PICU size, and the unit of inference was the patient. Study execution was revised based on our Data and Safety Monitoring Board’s recommendation to consult with the Department of Health and Human Services’ Office of Human Research Protection (OHRP) on how best to consent eligible subjects. OHRP deemed that the RESTORE intervention posed greater than minimal risk and that all enrolled subjects provide consent reflecting their level of participation.

Results

Thirty-one PICUs of varying size, organization and academic affiliation participated and over 2800 critically ill infants and children supported on mechanical ventilation for acute pulmonary disease were enrolled. The primary outcome for the trial was the duration of mechanical ventilation; secondary outcomes included time awake and comfortable, total sedative exposure and iatrogenic withdrawal symptoms. Throughout the clinical trial the investigative team worked to maintain treatment fidelity, enrollment milestones and co-investigator enthusiasm. We considered the potential impact of competing clinical trials through a decision-making framework.

Conclusions

The RESTORE clinical trial was a large and complex multicenter study that has provided the necessary evidence to guide sedation practices in the field of pediatric critical care. Specific issues that were unique to this trial included level of consent, adding clinical sites to augment enrollment and evaluating the potential impact of competing clinical trials.

Trial registration

ClinicalTrials.gov, Identifiers: Pilot trial: NCT00142766; Retrospectively registerd on 2 September 2005.

Cluster randomized trial: NCT00814099. Registered on 23 December 2008.

Consensus Recommendations for RBC Transfusion Practice in Critically Ill Children From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To date, there are no published guidelines to direct RBC transfusion decision-making specifically for critically ill children. We present the recommendations from the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

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

SETTING

Not applicable.

INTERVENTION

None.

SUBJECTS

Children with, or children at risk for, critical illness who receive or are at risk for receiving a RBC transfusion.

METHODS

A panel of 38 content and four methodology experts met over the course of 2 years to develop evidence-based, and when evidence lacking, expert consensus-based recommendations regarding decision-making for RBC transfusion management and research priorities for transfusion in critically ill children. The experts focused on nine specific populations of critically ill children: general, respiratory failure, nonhemorrhagic shock, nonlife-threatening bleeding or hemorrhagic shock, acute brain injury, acquired/congenital heart disease, sickle cell/oncology/transplant, extracorporeal membrane oxygenation/ventricular assist/ renal replacement support, and alternative processing. Data to formulate evidence-based and expert consensus recommendations were selected based on searches of PubMed, EMBASE, and Cochrane Library 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.

MEASUREMENTS AND RESULTS

The Transfusion and Anemia Expertise Initiative consensus conference developed and reached consensus on a total of 102 recommendations (57 clinical [20 evidence based, 37 expert consensus], 45 research recommendations). All final recommendations met agreement, defined a priori as greater than 80%. A decision tree to aid clinicians was created based on the clinical recommendations.

CONCLUSIONS

The Transfusion and Anemia Expertise Initiative recommendations provide important clinical guidance and applicable tools to avoid unnecessary RBC transfusions. Research recommendations identify areas of focus for future investigation to improve outcomes and safety for RBC transfusion.

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.

Recommendations on RBC Transfusions in Critically Ill Children With Acute Respiratory Failure 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 bleeding developed by 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 clinical recommendations as well as research priorities for RBC transfusions in critically ill children. The respiratory subgroup included six 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

Transfusion and Anemia Expertise Initiative experts developed seven recommendations focused on children with acute respiratory failure. All recommendations reached agreement (> 80%). Transfusion of RBCs in children with respiratory failure with an hemoglobin level less than 5 g/dL was strongly recommended. It was strongly recommended that RBCs not be systematically administered to children with respiratory failure who are hemodynamically stable and who have a hemoglobin level greater than or equal to 7 g/dL. Experts could not make a recommendation for children with hemodynamic instability, with severe hypoxemia and/or with an hemoglobin level between 5 and 7 g/dL. Specific RBC transfusion strategies using physiologic-based metrics and biomarkers could not be elaborated.

CONCLUSIONS

The Transfusion and Anemia Expertise Initiative Consensus Conference developed specific recommendations regarding RBC transfusion management in critically ill children with respiratory failure, as well as recommendations to guide future research. Clinical recommendations emphasize relevant hemoglobin thresholds. Research recommendations emphasize the need to identify appropriate physiologic thresholds, suggest a better understanding of alternatives to RBC transfusion, and identify the need for better evidence on hemoglobin thresholds that might be used in specific subpopulations of critically ill children.

RBC Exposure in Pediatric Extracorporeal Membrane Oxygenation: Epidemiology and Factors Associated With Large Blood Transfusion Volume

OBJECTIVES

To quantify and identify factors associated with large RBC exposure in children supported with extracorporeal membrane oxygenation.

DESIGN

Retrospective cohort study.

SETTING

Single tertiary care children's hospital.

PATIENTS

One-hundred twenty-two children supported with extracorporeal membrane oxygenation for greater than 12 hours during January 1, 2015, to December 31, 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Clinical, laboratory, and survival data were obtained from medical records. Only data from patients' first extracorporeal membrane oxygenation run were used. The primary outcome was RBC volume exposure during extracorporeal membrane oxygenation (mL/kg/d). Patients with RBC exposure volume greater than 75th percentile were categorized as "high RBC use" patients. A "bleeding day" was identified if mediastinum or cannula sites were explored and/or Factor VIIa administration, gastrointestinal, pulmonary, or intracranial hemorrhages occurred. Median age was 0.3 years (interquartile range, 0-3 yr). Congenital heart disease (n = 56; 46%) was the most common diagnosis. Median RBC volume transfused during extracorporeal membrane oxygenation was 39 mL/kg/d (interquartile range, 21-66 mL/kg/d). High RBC use patients were more likely be supported by venoarterial extracorporeal membrane oxygenation (100 vs 76%; p = 0.006), have congenital heart disease (68 vs 39%; p = 0.02), and experience bleeding (33 vs 11% d; p < 0.001). High RBC use patients showed a trend toward higher in-hospital mortality (58 vs 37%; p = 0.07). In the multivariable analysis, younger age (-9% per year; 95% CI, -10% to -7%; p < 0.001), more blood draws per day (+8%; 95% CI, 6-11%; p < 0.001), and higher proportion of bleeding days (+22% per 10% increase; 95% CI, 16-29%; p < 0.001) were associated with larger RBC exposure (model R = 0.66).

CONCLUSIONS

Bleeding during extracorporeal membrane oxygenation, frequent laboratory draws, and younger age were associated with increased RBC exposure during extracorporeal membrane oxygenation. Higher transfusion volume was associated with increased mortality.

A Standard Push-Pull Protocol for Waste-Free Sampling in the Pediatric Intensive Care Unit

Blood sampling is a major source of blood loss in the pediatric intensive care unit (PICU). Blood-sparing sampling techniques such as the push-pull method can significantly reduce sampling-related blood loss and protect patients from anemia and blood transfusions. The push-pull method is supported by research evidence for central venous catheter (CVC) sampling, but research protocols differ and not all CVCs and laboratory tests have been studied. A standard push-pull protocol for the PICU was developed, implemented, and evaluated in this evidence-based practice project. Results show that the protocol can be used safely and reliably as a standard waste-free sampling method in the PICU.

Red blood cell transfusion in infants and children - Current perspectives

Children routinely receive packed red blood transfusion when they are admitted in the intensive care unit or undergoing cardiac surgeries. These guidelines aim to summarize literature and provide transfusion triggers exclusively in infants and children.

Measurement of Intraoperative Blood Loss in Pediatric Orthopaedic Patients: Evaluation of a New Method

Introduction:

Our goal was to validate a new method of intraoperative blood loss measurement in pediatric patients who undergo orthopaedic surgery.

Methods:

We prospectively collected surgical sponges from 55 patients who underwent pediatric posterior spinal fusion, single-event multilevel surgery, or hip reconstruction for measurement of intraoperative blood loss. We enrolled patients if expected estimated blood loss (EBL) was >200 mL. The methods used for blood loss assessment included the Triton sponge scanning system, visual method, gravimetric method, and measured assay (reference) method.

Results:

The Triton system calculation of cumulative EBL per patient against the reference method yielded a strong positive linear correlation (R² = 0.88). A weaker correlation was noted between the gravimetric method and reference EBL (R² = 0.49). The Triton system had a low bias and narrow limits of agreement relative to the reference method (49 mL; 95% CI, 30 to 68). The gravimetric method had a higher bias and wider limits of agreement (101 mL; 95% CI, 67 to 135). The comparison of visual total EBL against the reference method yielded a notable discrepancy.

Discussion:

Estimated blood loss measured using the Triton system correlated better with the reference method than with the gravimetric method. The visual estimation method was found to be inaccurate. Intraoperative use of the Triton system is convenient and precise for monitoring intraoperative blood loss.

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 Analysis of Liberal and Restrictive Transfusion Strategies in Pediatric Intensive Care Unit

BACKGROUND

We prospectively compared restrictive and liberal transfusion strategies for critically ill children regarding hemodynamic and laboratory parameters.

METHODS

A total of 180 children requiring packed red blood cells (PRBCs) were randomized into two groups: the liberal transfusion strategy group (transfusion trigger < 10 g/dL, Group 1) and the restrictive transfusion strategy group (transfusion trigger ≤ 7 g/dL, Group 2). Basal variables including venous/arterial hemoglobin, hematocrit and lactate levels; stroke volume; and cardiac output were recorded at the beginning and end of the transfusion. Oxygen saturation, noninvasive total hemoglobin, noninvasive total oxygen content, perfusion index (PI), heart rate and systolic and diastolic blood pressures were assessed via the Radical-7 Pulse co-oximeter (Masimo, Irvine, CA, USA) with the Root monitor, initially and at 4 h.

RESULTS

In all, 160 children were eligible for final analysis. The baseline hemoglobin level for the PRBC transfusion was 7.38 ± 0.98 g/dL for all patients. At the end of the PRBC transfusion, cardiac output decreased by 9.9% in Group 1 and by 24% in Group 2 (p  < 0.001); PI increased by 10% in Group 1 and by 45% in Group 2 (p  < 0.001). Lactate decreased by 9.8% in Group 1 and by 31.68% in Group 2 (p < 0.001).

CONCLUSION

Restrictive blood transfusion strategy is better than liberal transfusion strategy with regard to the hemodynamic and laboratory values during the early period. PI also provides valuable information regarding the efficacy of PRBC transfusion in clinical practice.

RBC Transfusions Are Associated With Prolonged Mechanical Ventilation in Pediatric Acute Respiratory Distress Syndrome

OBJECTIVES

Blood products are often transfused in critically ill children, although recent studies have recognized their potential for harm. Translatability to pediatric acute respiratory distress syndrome is unknown given that hypoxemia has excluded pediatric acute respiratory distress syndrome patients from clinical trials. We aimed to determine whether an association exists between blood product transfusion and survival or duration of ventilation in pediatric acute respiratory distress syndrome.

DESIGN

Retrospective analysis of prospectively enrolled cohort.

SETTING

Large, academic PICU.

PATIENTS

Invasively ventilated children meeting Berlin Acute Respiratory Distress Syndrome and Pediatric Acute Lung Injury Consensus Conference Pediatric Acute Respiratory Distress Syndrome criteria from 2011 to 2015.

INTERVENTIONS

We recorded transfusion of RBC, fresh frozen plasma, and platelets within the first 3 days of pediatric acute respiratory distress syndrome onset. Each product was tested for independent association with survival (Cox) and duration of mechanical ventilation (competing risk regression with extubation as primary outcome and death as competing risk). A sensitivity analysis using 1:1 propensity matching was also performed.

MEASUREMENTS AND MAIN RESULTS

Of 357 pediatric acute respiratory distress syndrome patients, 155 (43%) received RBC, 82 (23%) received fresh frozen plasma, and 92 (26%) received platelets. Patients who received RBC, fresh frozen plasma, or platelets had higher severity of illness score, lower PaO2/FIO2, and were more often immunocompromised (all p < 0.05). Patients who received RBC, fresh frozen plasma, or platelets had worse survival and longer duration of ventilation by univariate analysis (all p < 0.05). After multivariate adjustment for above confounders, no blood product was associated with survival. After adjustment for the same confounders, RBC were associated with decreased probability of extubation (subdistribution hazard ratio, 0.65; 95% CI, 0.51-0.83). The association between RBC and prolonged ventilation was confirmed in propensity-matched subgroup analysis.

CONCLUSIONS

RBC transfusion was independently associated with longer duration of mechanical ventilation in pediatric acute respiratory distress syndrome. Hemoglobin transfusion thresholds should be tested specifically within pediatric acute respiratory distress syndrome to establish whether a more restrictive transfusion strategy would improve outcomes.

Mechanisms of red blood cell transfusion-related immunomodulation

Red blood cell (RBC) transfusion is common in critically ill, postsurgical, and posttrauma patients in whom both systemic inflammation and immune suppression are associated with adverse outcomes. RBC products contain a multitude of immunomodulatory mediators that interact with and alter immune cell function. These interactions can lead to both proinflammatory and immunosuppressive effects. Defining clinical outcomes related to immunomodulatory effects of RBCs in transfused patients remains a challenge, likely due to complex interactions between individual blood product characteristics and patient-specific risk factors. Unpacking these complexities requires an in-depth understanding of the mechanisms of immunomodulatory effects of RBC products. In this review, we outline and classify potential mediators of RBC transfusion-related immunomodulation and provide suggestions for future research directions.

The Effect of Diagnostic Blood Loss on Anemia and Transfusion Among Postoperative Patients With Congenital Heart Disease in a Pediatric Intensive Care Unit

PURPOSE

To evaluate whether diagnostic blood loss can lead to anemia and consequent blood transfusion among postoperative patients with congenital heart disease (CHD) in the pediatric intensive care unit (PICU).

DESIGN AND METHODS

This prospective observational study was conducted in a university-affiliated tertiary hospital between January and August 2016. CHD patients aged <12years, undergoing cardiac surgery, with a PICU stay >48h were included (n=205). Multivariate logistic regression analyses were used to determine the effect of diagnostic blood loss on anemia and transfusion.

RESULTS

The mean daily phlebotomy volume was 5.40±1.94mL/d during the PICU stay (adjusted for body weight, 0.63±0.36mL/kg/d). Daily volume/kg was associated with cyanotic CHD, Pediatric Risk of Mortality III score, and Pediatric Logistic Organ Dysfunction (PELOD)-2 score. In total, 101 (49.3%) patients presented with new or more severe anemia after admission to PICU, which was not associated with phlebotomy volume. Forty-one (20.0%) children received one or more RBC transfusions during their PICU stay. Multivariate analysis indicated that PELOD-2 score>5, new or more severe anemia, and daily volume/kg of phlebotomy >0.63mL/kg/d were significantly associated with transfusion after 48h of admission to PICU.

CONCLUSIONS

Our findings indicate that diagnostic blood loss is not related to postoperative anemia in children with CHD; however, this factor does correlate with blood transfusion, since it somewhat reflects the severity of illness.

PRACTICE IMPLICATIONS

Strategies should be applied to reduce diagnostic blood loss, as appropriate.

Noninvasive Measurement of Hemoglobin Using Spectrophotometry: Is it Useful for the Critically Ill Child?

This study compared the accuracy of noninvasively measuring hemoglobin using spectrophotometry (SpHb) with a pulse CO-oximeter and laboratory hemoglobin (Hb) measurements. A total of 345 critically ill children were included prospectively. Age, sex, and factors influencing the reliabilityof SpHb such as SpO2, heart rate, perfusion index (PI), and vasoactive inotropic score were recorded. SpHb measurements were recorded during the blood draw and compared with the Hb measurement. Thirteen patients (low PI in 9 patients and no available Hb in 4 patients) were excluded and 332 children were eligible for final analysis. The mean Hb was 8.71±1.49 g/dL (range, 5.9 to 12 g/dL) and the mean SpHb level was 9.55±1.53 g/dL (range, 6 to 14.2 g/dL). The SpHb bias was 0.84±0.86,with the limits of agreement ranging from -2.5 to 0.9 g/dL. The difference between Hb and SpHb was >1.5 g/dL for only 47 patients. Of these, 24 patients had laboratory Hb levels <7 g/dL. There was a weak positive correlation between differences and PI (r=0.349; P= 0.032). The pulse CO-oximeter is a promising tool for measuring SpHb and monitoring critically ill children. However, PI may affect these results. Additional studies investigating the reliability of the trend of continuous SpHb values compared with simultaneously measured laboratory Hb values in the same patient are warranted.

Efficacy of Supplementation with Iron Sulfate Compared to Iron Bisglycinate Chelate in Preterm Infants

BACKGROUND

Strategies to prevent anaemia in preterm infants include drawing fewer blood samples, the use of recombinant human erythropoietin and iron supplementation. Although iron sulfate is the most commonly used pharmaceutical formulation for iron supplementation, there are few studies comparing different iron salts in infants.

OBJECTIVE

This is a study of retrospective data comparison of two groups of preterm infants receiving erythropoietin to evaluate the efficacy of iron bisglycinate chelate to iron sulfate.

SUBJECTS AND METHODS

Three-hundred infants of gestational age ≤32 weeks were enrolled: 225 were supplemented with iron sulfate (3 mg/kg/day) and 75 were supplemented with iron bisglycinate chelate (0.75 mg/kg/day). The effect on erythropoiesis was assessed with a general linear model that estimates the response variables (values for Haemoglobin, Haematocrit, absolute values and percentage Reticulocytes, Reticulocyte Haemoglobin content) based on treatment, time, birth weight, and gestational age.

RESULTS

Supplementation with iron bisglycinate chelate at a dose of 0.75 mg/kg/day demonstrated an efficacy comparable to iron sulfate at a dose of 3 mg/kg/day in both populations of preterm infants. The two cohorts had similar erythropoietic response, without significant differences.

CONCLUSIONS

The higher bioavailability of iron bisglycinate chelate resulted in a lower load of elemental iron, a quarter of the dose, and achieved equivalent efficacy compared to iron sulfate. Iron bisglycinate chelate may appear to be an alternative to iron sulfate in the prevention and treatment of preterm newborn anaemia.

Engineering of a miniaturized, robotic clinical laboratory

The ability to perform laboratory testing near the patient and with smaller blood volumes would benefit patients and physicians alike. We describe our design of a miniaturized clinical laboratory system with three components: a hardware platform (ie, the miniLab) that performs preanalytical and analytical processing steps using miniaturized sample manipulation and detection modules, an assay-configurable cartridge that provides consumable materials and assay reagents, and a server that communicates bidirectionally with the miniLab to manage assay-specific protocols and analyze, store, and report results (i.e., the virtual analyzer). The miniLab can detect analytes in blood using multiple methods, including molecular diagnostics, immunoassays, clinical chemistry, and hematology. Analytical performance results show that our qualitative Zika virus assay has a limit of detection of 55 genomic copies/ml. For our anti-herpes simplex virus type 2 immunoglobulin G, lipid panel, and lymphocyte subset panel assays, the miniLab has low imprecision, and method comparison results agree well with those from the United States Food and Drug Administration-cleared devices. With its small footprint and versatility, the miniLab has the potential to provide testing of a range of analytes in decentralized locations.

Reducing Blood Testing in Pediatric Patients after Heart Surgery: Proving Sustainability

Introduction

Frequent blood testing increases risk of iatrogenic anemia, infection, and blood transfusion. This study describes 3 years of sustained blood testing reduction from a quality improvement (QI) initiative which began in 2011.

Methods

The cohort consisted of postop children whose surgery had a Risk Adjustment for Congenital Heart Surgery (RACHS) classification consecutively admitted to a tertiary Cardiac Intensive Care Unit. Data were collected for a 2010 preintervention, 2011 intervention, and 2012-13 postintervention periods, tabulating common laboratory studies per patient (labs/pt) and adjusted for length of stay (labs/pt/d). The QI initiative eliminated standing laboratory orders and changed to testing based on individualized patient condition. Adverse outcomes data were collected including reintubation, central line-associated bloodstream infections and hospital mortality. Safety was measured by the number of abnormal laboratory studies, electrolyte replacements, code blue events, and arrhythmias.

Results

A total of 1169 patients were enrolled (303 preintervention, 315 intervention, and 551 postintervention periods). The number of labs/pt after the QI intervention was sustained (38 vs. 23 vs. 23) and labs/pt/d (15 vs. 11 vs. 10). The postintervention group had greater surgical complexity (P = 0.002), were significantly younger (P = 0.002) and smaller (P = 0.008). Children with RACHS 3-4 classification in the postintervention phase had significant increased risk of reintubation and arrhythmias.

Conclusions

After the implementation of a QI initiative, blood testing was reduced and sustained in young, complex children after heart surgery. This may or may not have contributed to greater reintubation and arrhythmias among patients with RACHS 3-4 category procedures.

Assessment of Micronutrient Status in Critically Ill Children: Challenges and Opportunities

Micronutrients refer to a group of organic vitamins and inorganic trace elements that serve many functions in metabolism. Assessment of micronutrient status in critically ill children is challenging due to many complicating factors, such as evolving metabolic demands, immature organ function, and varying methods of feeding that affect nutritional dietary intake. Determination of micronutrient status, especially in children, usually relies on a combination of biomarkers, with only a few having been established as a gold standard. Almost all micronutrients display a decrease in their serum levels in critically ill children, resulting in an increased risk of deficiency in this setting. While vitamin D deficiency is a well-known phenomenon in critical illness and can predict a higher need for intensive care, serum concentrations of many trace elements such as iron, zinc, and selenium decrease as a result of tissue redistribution in response to systemic inflammation. Despite a decrease in their levels, supplementation of micronutrients during times of severe illness has not demonstrated clear benefits in either survival advantage or reduction of adverse outcomes. For many micronutrients, the lack of large and randomized studies remains a major hindrance to critically evaluating their status and clinical significance.

Anemia at pediatric intensive care unit discharge: prevalence and risk markers

BACKGROUND

Anemia is prevalent at pediatric intensive care unit (PICU) admission and incident during PICU stay, but little is known about anemia at PICU discharge . Anemia after critical illness is an important issue because it could impact post-PICU outcome. We aimed to estimate the prevalence of anemia at PICU discharge and to determine its risk markers.

METHODS

This is an ancillary study of a prospective observational study on transfusion practices conducted in the PICU of a tertiary care children's hospital. All children consecutively admitted to the PICU during a 1-year period were considered for inclusion. Data were prospectively collected from medical charts, except for hemoglobin (Hb) levels at PICU and hospital discharge that were collected retrospectively. Anemia was defined by an Hb concentration below the lower limit of the normal range for age.

RESULTS

Among the 679 children retained for analysis, 390 (57.4%) were anemic at PICU discharge. After multivariate adjustment, anemia at PICU admission was the strongest risk marker of anemia at PICU discharge. The strength of this association varied according to age (interaction): The odds ratio (OR) (95% CI) of anemia at PICU discharge was 4.85 (1.67-14.11) for 1-5-month-old infants anemic versus not anemic at PICU admission, and it was 73.13 (13.43, 398.19) for adolescents anemic versus not anemic at PICU admission. Children admitted after a non-cardiac surgery had an increased risk of anemia at PICU discharge [OR 2.30 (1.37, 3.88), p = 0.002]. The proportion of anemic children differed between age categories, while the median Hb level did not exhibit significant variations according to age.

CONCLUSIONS

Anemia is highly prevalent at PICU discharge and is strongly predicted by anemia at PICU admission. The usual age-based definitions of anemia may not be relevant for critically ill children. The consequences of anemia at PICU discharge are unknown and deserve further scrutiny.

Transfusion Decision Making in Pediatric Critical Illness

Transfusion decision making (TDM) in the critically ill requires consideration of: (1) anemia tolerance, which is linked to active pathology and to physiologic reserve, (2) differences in donor RBC physiology from that of native RBCs, and (3) relative risk from anemia-attributable oxygen delivery failure vs hazards of transfusion, itself. Current approaches to TDM (e.g. hemoglobin thresholds) do not: (1) differentiate between patients with similar anemia, but dissimilar pathology/physiology, and (2) guide transfusion timing and amount to efficacy-based goals (other than resolution of hemoglobin thresholds). Here, we explore approaches to TDM that address the above gaps.

Factors Associated with Bleeding and Thrombosis in Children Receiving Extracorporeal Membrane Oxygenation

RATIONALE

Extracorporeal membrane oxygenation (ECMO) is used for respiratory and cardiac failure in children but is complicated by bleeding and thrombosis.

OBJECTIVES

(1) To measure the incidence of bleeding (blood loss requiring transfusion or intracranial hemorrhage) and thrombosis during ECMO support; (2) to identify factors associated with these complications; and (3) to determine the impact of these complications on patient outcome.

METHODS

This was a prospective, observational cohort study in pediatric, cardiac, and neonatal intensive care units in eight hospitals, carried out from December 2012 to September 2014.

MEASUREMENTS AND MAIN RESULTS

ECMO was used on 514 consecutive patients under age 19 years. Demographics, anticoagulation practices, severity of illness, circuitry components, bleeding, thrombotic events, and outcome were recorded. Survival was 54.9%. Bleeding occurred in 70.2%, including intracranial hemorrhage in 16%, and was independently associated with higher daily risk of mortality. Circuit component changes were required in 31.1%, and patient-related clots occurred in 12.8%. Laboratory sampling contributed to transfusion requirement in 56.6%, and was the sole reason for at least one transfusion in 42.2% of patients. Pump type was not associated with bleeding, thrombosis, hemolysis, or mortality. Hemolysis was predictive of subsequent thrombotic events. Neither hemolysis nor thrombotic events increased the risk of mortality.

CONCLUSIONS

The incidences of bleeding and thrombosis are high during ECMO support. Laboratory sampling is a major contributor to transfusion during ECMO. Strategies to reduce the daily risk of bleeding and thrombosis, and different thresholds for transfusion, may be appropriate subjects of future trials to improve outcomes of children requiring this supportive therapy.

Reducing Unnecessary Postoperative Complete Blood Count Testing in the Pediatric Intensive Care Unit

CONTEXT

Complete blood count (CBC) testing commonly occurs to determine the need for blood transfusions after surgical procedures. Many clinicians believe postoperative CBCs are "routine."

OBJECTIVE

To decrease unnecessary routine CBC testing in a low-risk cohort of postoperative patients in the pediatric intensive care unit (PICU) at The Children's Hospital of Philadelphia by 50% in 6 months.

DESIGN

Quality-improvement study. Data from our institution regarding frequency of ordering laboratory studies and transfusion requirements were collected for prior quality-improvement work demonstrating the safety and feasibility of avoiding routine postoperative CBCs in this cohort. Baseline survey data were gathered from key stakeholders on attitudes about and utilization of routine postoperative laboratory testing. Patient and clinician data were shared with all PICU clinicians. Simple Plan-Do-Study-Act cycles involving education, audit, and feedback were put into place.

MAIN OUTCOME MEASURES

Percentage of postoperative patients receiving CBCs within 48 hours of PICU admission. Balancing measures were hemoglobin level below 8 g/dL in patients for whom CBCs were sent and blood transfusions up to 7 days postoperatively for any patients in this cohort.

RESULTS

Sustained decreases below our 50% goal were seen after our interventions. There were no hemoglobin results below 8 g/dL or surgery-related blood transfusions in this cohort within 7 days of surgery. Estimated hospital charges related to routine postoperative CBCs decreased by 87% during 6 postintervention months.

CONCLUSION

A simple approach to a systemic problem in the PICU of unnecessary laboratory testing is feasible and effective. By using local historical data, we were able to identify a cohort of patients for whom routine postoperative CBC testing is unnecessary.

Controlling Phlebotomy Volume Diminishes PICU Transfusion: Implementation Processes and Impact

BACKGROUND AND OBJECTIVES

Phlebotomy excess contributes to anemia in PICU patients and increases the likelihood of red blood cell transfusion, which is associated with risk of adverse outcomes. Excessive phlebotomy reduction (EPR) strategies may reduce the need for transfusion, but have not been evaluated in a PICU population. We hypothesized that EPR strategies, facilitated by implementation science methods, would decrease excess blood drawn and reduce transfusion frequency.

METHODS

Quantitative and qualitative methods were used. Patient and blood draw data were collected with survey and focus group data to evaluate knowledge and attitudes before and after EPR intervention. The Consolidated Framework for Implementation Research was used to interpret qualitative data. Multivariate regression was employed to adjust for potential confounders for blood overdraw volume and transfusion incidence.

RESULTS

Populations were similar pre- and postintervention. EPR strategies decreased blood overdraw volumes 62% from 5.5 mL (interquartile range 1-23) preintervention to 2.1 mL (interquartile range 0-7.9 mL) postintervention (P < .001). Fewer patients received red blood cell transfusions postintervention (32.1% preintervention versus 20.7% postintervention, P = .04). Regression analyses showed that EPR strategies reduced blood overdraw volume (P < .001) and lowered transfusion frequency (P = .05). Postintervention surveys reflected a high degree of satisfaction (93%) with EPR strategies, and 97% agreed EPR was a priority postintervention.

CONCLUSIONS

Implementation science methods aided in the selection of EPR strategies and enhanced acceptance which, in this cohort, reduced excessive overdraw volumes and transfusion frequency. Larger trials are needed to determine if this approach can be applied in broader PICU populations.

Epidemiology of Bleeding in Critically Ill Children

OBJECTIVE

To determine the epidemiology of bleeding in critically ill children.

STUDY DESIGN

We conducted a cohort study of children <18 years old admitted to the pediatric intensive care unit for >24 hours and without clinically relevant bleed (CRB) on admission. CRB was defined as resulting in severe physiologic derangements, occurring at a critical site or requiring major therapeutic interventions. Using a novel bleeding assessment tool that we developed, characteristics of the CRB were abstracted from the medical records independently and in duplicate. From the cohort, we matched each child with CRB to 4 children without CRB based on onset of CRB. Risk factors and complications of CRB were identified from this matched group of children.

RESULTS

We analyzed 405 children with a median age of 35 months (IQR 7-130 months). A total of 37 (9.1%) children developed CRB. The median number of days with CRB was 1 day (IQR 1-2 days). Invasive ventilation (OR 61.35; 95% CI 6.27-600.24), stress ulcer prophylaxis (OR 2.70; 95% CI 1.08-6.74), surgical admission (OR 0.29; 95% CI 0.10-0.84), and aspirin (OR 0.04; 95% CI 0.002-0.58) were associated with CRB. CRB was associated with longer time to discharge from the unit (hazard ratio 0.20; 95% CI 0.13-0.33) and the hospital (hazard ratio 0.49; 95% CI 0.33-0.73). Children with CRB were on vasopressor longer and transfused more red blood cells after the CRB than those without CRB.

CONCLUSIONS

Our findings suggest that bleeding complicates critical illness in children.