Bleeding Scales Applicable to Critically Ill Children: A Systematic Review

Short-term neurologic outcomes in pediatric extracorporeal membrane oxygenation are proportional to bleeding severity graded by a novel bleeding scale

INTRODUCTION

This study aimed to characterize the severity of bleeding and its association with short-term neurologic outcomes in pediatric ECMO.

METHODS

Multicenter retrospective cohort study of pediatric ECMO patients at 10 centers utilizing the Pediatric ECMO Outcomes Registry (PEDECOR) database from December 2013-February 2019. Subjects excluded were post-cardiac surgery patients and those with neonatal pathologies. A novel ECMO bleeding scale was utilized to categorize daily bleeding events. Poor short-term neurologic outcome was defined as an unfavorable Pediatric Cerebral Performance Category (PCPC) or Pediatric Overall Performance Category (POPC) (score of >3) at hospital discharge.

RESULTS

This study included 283 pediatric ECMO patients with a median (interquartile range [IQR]) age of 1.3 years [0.1, 9.0], ECMO duration of 5 days [3.0, 9.5], and 44.1% mortality. Unfavorable PCPC and POPC were observed in 48.4% and 51.3% of patients at discharge, respectively. Multivariable logistic regression analysis included patient's age, cannulation type, duration of ECMO, need for cardiopulmonary resuscitation, acute kidney injury, new infection, and vasoactive-inotropic score. As the severity of bleeding increased, there was a corresponding increase in the likelihood of poor neurologic recovery, shown by increasing odds of unfavorable neurologic outcome (PCPC), with an adjusted odds ratio (aOR) of 0.77 (confidence interval [CI] 0.36-1.62), 1.87 (0.54-6.45), 2.97 (1.32-6.69), and 5.56 (0.59-52.25) for increasing bleeding severity (grade 1 to 4 events, respectively). Similarly, unfavorable POPC aOR (CI) was 1.02 (0.48-2.17), 2.05 (0.63-6.70), 5.29 (2.12-13.23), and 5.11 (0.66-39.64) for bleeding grade 1 to 4 events.

CONCLUSION

Short-term neurologic outcomes in pediatric ECMO are proportional to the severity of bleeding events. Strategies to mitigate bleeding events could improve neurologic recovery in pediatric ECMO.

Bleeding Scoring Systems in Neonates: A Systematic Review

We conducted a systematic review aiming to summarize the data on the current hemorrhage prediction models and evaluate their potential for generalized application in the neonatal population. The electronic databases PubMed and Scopus were searched, up to September 20, 2023, for studies that focused on development and/or validation of a prediction model for bleeding risk in neonates, and described the process of model building. Nineteen studies fulfilled the inclusion criteria for the present review. Eighteen bleeding risk prediction models in the neonatal population were identified, four of which were internally validated, one temporally and one externally validated. The existing prediction models for neonatal hemorrhage are mostly based on clinical variables and do not take into account the clinical course and hemostatic profile of the neonates. Most studies aimed at predicting the risk of intraventricular hemorrhage (IVH) reflecting the fact that IVH is the most frequent and serious bleeding complication in preterm neonates. A justification for the study sample size for developing the prediction model was given only by one study. Prediction and stratification of risk of hemorrhage in neonates is yet to be optimized. To this end, qualitative standards for model development need to be further improved. The assessment of the risk of bleeding incorporating platelet count, coagulation parameters, and a set of relevant clinical variables is crucial. Large, rigorous, collaborative cohort studies are warranted to develop a robust prediction model to inform the need for transfusion, which is a fundamental step towards personalized transfusion therapy in neonates.

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.

Bleeding in Critically Ill Children With Malignancy or Hematopoietic Cell Transplant: A Single-Center Prospective Cohort Study

OBJECTIVES

To determine the incidence of bleeding in critically ill children with malignancy and to describe associated patient characteristics, interventions, and clinical outcomes.

DESIGN

Prospective cohort study.

SETTING

PICU in a specialized cancer hospital.

PATIENTS

Children with malignancy or hematopoietic cell transplant 0-18 years of age were admitted to the PICU from November 2020 to November 2021.

INTERVENTIONS

None.

MEASUREMENTS

Patient demographic data, laboratory values, and PICU outcome data were collected. Bleeding was classified according to the Bleeding Assessment Scale in Critically Ill Children.

MAIN RESULTS

Ninety-three bleeding patients were enrolled, and a total of 322 bleeding days were recorded. The median (interquartile range [IQR]) age was 5.8 (2.9-11.8) years and 56% (52/93) of the patients were male. There were 121 new bleeding episodes, in 593 at-risk person-days, translating into a 20% incidence rate per day (95% CI, 17-24%). The incidence of severe, moderate, and minimal bleeding was 2% (95% CI, 1-3), 4% (95% CI, 3-6), and 14% (95% CI, 12-17), respectively. Of the new bleeding episodes, 9% were severe, 25% were moderate and 66% were minimal. Thrombocytopenia was the only laboratory value independently associated with severe bleeding ( p = 0.009), as compared to minimal and moderate bleeding episodes. History of radiation therapy was independently associated with severe bleeding ( p = 0.04). We failed to identify an association between a history of stem cell transplant ( p = 0.49) or tumor type ( p = 0.76), and bleeding severity. Patients were transfused any blood product on 28% (95% CI, 22-34) of the bleeding days. Severe bleeding was associated with increased length of mechanical ventilation ( p = 0.003), longer PICU stays ( p = 0.03), and higher PICU mortality ( p = 0.004).

CONCLUSIONS

In this prospective cohort of children with malignancy, the incidence rate of bleeding was 20%. Most events were classified as minimal bleeding. Low platelet count and radiation therapy were variables independently associated with severe bleeding episodes.

Epidemiology of severe bleeding in children following cardiac surgery involving cardiopulmonary bypass: use of Bleeding Assessment Scale for critically Ill Children (BASIC)

OBJECTIVES

To describe the epidemiology of severe bleeding in the immediate post-operative period in children who undergo cardiopulmonary bypass surgery using the Bleeding Assessment Scale for critically Ill Children (BASIC).

STUDY DESIGN

Retrospective cohort study in a paediatric ICU from 2015 to 2020.

RESULTS

356 children were enrolled; 59% were male with median (IQR) age 2.1 (0.5-8) years. Fifty-seven patients (16%) had severe bleeding in the first 24 hours post-operatively. Severe bleeding was observed more frequently in younger and smaller children with longer bypass and cross-clamp times (p-values <0.001), in addition to higher surgical complexity (p = 0.048). Those with severe bleeding received significantly more red blood cells, platelets, plasma, and cryoprecipitate in the paediatric ICU following surgery (all p-values <0.001). No laboratory values obtained on paediatric ICU admission were able to predict severe post-operative bleeding. Those with severe bleeding had significantly less paediatric ICU-free days (p = 0.010) and mechanical ventilation-free days (p = 0.013) as compared to those without severe bleeding.

CONCLUSIONS

Applying the BASIC definition to our cohort, severe bleeding occurred in 16% of children in the first day following cardiopulmonary bypass. Severe bleeding was associated with worse clinical outcomes. Standard laboratory assays do not predict bleeding warranting further study of available laboratory tests.

What Laboratory Tests and Physiologic Triggers Should Guide the Decision to Administer a Platelet or Plasma Transfusion in Critically Ill Children and What Product Attributes Are Optimal to Guide Specific Product Selection? From the Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding

OBJECTIVES

To present consensus statements and supporting literature for plasma and platelet product variables and related laboratory testing for transfusions in general critically ill children from the Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding.

DESIGN

Systematic review and consensus conference of international, multidisciplinary experts in platelet and plasma transfusion management of critically ill children.

SETTING

Not applicable.

PATIENTS

Critically ill pediatric patients at risk of bleeding and receiving plasma and/or platelet transfusions.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A panel of 10 experts developed evidence-based and, when evidence was insufficient, expert-based statements for laboratory testing and blood product attributes for platelet and plasma transfusions. These statements were reviewed and ratified by the 29 Transfusion and Anemia EXpertise Initiative - Control/Avoidance of Bleeding experts. A systematic review was conducted using MEDLINE, EMBASE, and Cochrane Library databases, from inception to December 2020. Consensus was obtained using the Research and Development/University of California, Los Angeles Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method. We developed five expert consensus statements and two recommendations in answer to two questions: what laboratory tests and physiologic triggers should guide the decision to administer a platelet or plasma transfusion in critically ill children; and what product attributes are optimal to guide specific product selection?

CONCLUSIONS

The Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding program provides some guidance and expert consensus for the laboratory and blood product attributes used for decision-making for plasma and platelet transfusions in critically ill pediatric patients.

Bleeding in Critically Ill Children-Review of Literature, Knowledge Gaps, and Suggestions for Future Investigation

Clinically significant bleeding complicates up to 20% of admissions to the intensive care unit in adults and is associated with severe physiologic derangements, requirement for significant interventions and worse outcome. There is a paucity of published data on bleeding in critically ill children. In this manuscript, we will provide an overview of the epidemiology and characteristics of bleeding in critically ill children, address the association between bleeding and clinical outcomes, describe the current definitions of bleeding and their respective limitations, and finally provide an overview of current knowledge gaps and suggested areas for future research.

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.