A randomized trial of platelet transfusions over 30 vs 120 minutes: is there an effect on post-transfusion platelet counts?

Neonatal platelet transfusions: New evidence and the challenges of translating evidence-based recommendations into clinical practice

Platelet transfusions are a common intervention for thrombocytopenia. Although the main reason for transfusing platelets is to improve hemostasis, platelets have many additional physiological roles, including interactions with immune pathways. Much of the evidence base for safe and effective transfusions has been informed by randomized trials in adult patients with hematological malignancies. Only three randomized trials have been conducted in sick neonates. These trials have indicated evidence of harm, including a significantly higher rate of death or major bleeding within 28 days after randomization for the largest trial, which enrolled 660 infants. The overall research indicates limited effectiveness of platelet transfusions to reduce bleeding risk. It is important that the results of trials are implemented into practice, but uptake of research findings into neonatal medicine remains inconsistent, as for many areas of health care. There is a need to establish which potential implementation strategies (cost-) efficiently enact change, such as audit and feedback, automated reminder systems for ordering transfusions, and use of opinion leaders. Research is exploring potential mechanisms underlying the lack of effectiveness of platelet transfusions and the increased bleeding and mortality observed in neonatal randomized trials. One potential mechanism concerns the roles of platelets to promote excessive angiogenic signals during a vulnerable period of brain development. A further hypothesis explores the effects of transfusing "adult" platelets into "neonatal" thrombocytopenic blood on primary hemostasis and immune responses.

Neonatal platelet physiology and implications for transfusion

The neonatal hemostatic system is different from that of adults. The differences in levels of procoagulant and anticoagulant factors and the evolving equilibrium in secondary hemostasis during the transition from fetal/neonatal life to infancy, childhood, and adult life are known as "developmental hemostasis." In regard to primary hemostasis, while the number (150,000-450,000/µl) and structure of platelets in healthy neonates closely resemble those of adults, there are significant functional differences between neonatal and adult platelets. Specifically, platelets derived from both cord blood and neonatal peripheral blood are less reactive than adult platelets to agonists, such as adenosine diphosphate (ADP), epinephrine, collagen, thrombin, and thromboxane (TXA2) analogs. This platelet hyporeactivity is due to differences in expression levels of key surface receptors and/or in signaling pathways, and is more pronounced in preterm neonates. Despite these differences in platelet function, bleeding times and PFA-100 closure times (an in vitro test of whole-blood primary hemostasis) are shorter in healthy full-term infants than in adults, reflecting enhanced primary hemostasis. This paradoxical finding is explained by the presence of factors in neonatal blood that increase the platelet-vessel wall interaction, such as high von Willebrand factor (vWF) levels, predominance of ultralong vWF multimers, high hematocrit, and high red cell mean corpuscular volume. Thus, the hyporeactivity of neonatal platelets should not be viewed as a developmental deficiency, but rather as an integral part of a developmentally unique, but well balanced, primary hemostatic system. In clinical practice, due to the high incidence of bleeding (especially intraventricular hemorrhage, IVH) among preterm infants, neonatologists frequently transfuse platelets to non-bleeding neonates when platelet counts fall below an arbitrary limit, typically higher than that used in older children and adults. However, recent studies have shown that prophylactic platelet transfusions not only fail to decrease bleeding in preterm neonates, but are associated with increased neonatal morbidity and mortality. In this review, we will describe the developmental differences in platelet function and primary hemostasis between neonates and adults, and will analyze the implications of these differences to platelet transfusion decisions.

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.

Platelet Transfusion and Outcomes of Preterm Infants: A Cross-Sectional Study

BACKGROUND

Prophylactic platelet transfusion has been adopted as a ubiquitous practice in management of thrombocytopenia in preterm infants to reduce the risk of bleeding.

OBJECTIVES

The objectives of this study were to report the prevalence of platelet transfusion among preterm infants with thrombocytopenia and to assess the association of platelet transfusion with mortality and morbidity in this population.

METHODS

A cross-sectional study that utilized National Inpatient Sample for the years 2000-2017 was conducted. All preterm infants delivered nationally with birth weight (BW) <1,500 g or gestational age <32 weeks were included. Analyses were repeated after stratifying the population into 2 BW subcategories <1,000 g and 1,000-1,499 g. Logistic regression analysis was performed to adjust for confounding variables.

RESULTS

The study included 1,780,299 infants; of them, 22,609 (1.27%) were diagnosed with thrombocytopenia and 5,134 (22.7%) received platelet transfusion. Platelet transfusion was associated with significant increase in mortality (24.8 vs. 13.8%), retinopathy of prematurity (22.3 vs. 19.2%), severe intraventricular hemorrhage (18.3 vs. 10.1%), median length of hospital stays (51 vs. 47 days), and cost of hospitalization (USD 298,204 vs. USD 219,760). Increased mortality was noted in <1,000-g infants (aOR = 1.96, CI: 1.76-2.18, p < 0.001) and 1,000-1,499-g infants (aOR = 2.02, CI: 1.62-2.53, p < 0.001). Platelet transfusion increased over the years in infants with BW <1,000 g (p = 0.001) and in infants with BW 1,000-1,499 g (p < 0.001).

CONCLUSIONS

Platelet transfusion is associated with increased mortality and comorbidities in premature infants. There is a trend for increased utilization of platelet transfusions over the study period.

Picking up the Pace: Decreasing Platelet Administration Safely and Effectively

BACKGROUND

Hematology-oncology patients often require blood and blood product transfusions, including platelets (PLTs), to maintain stability. Administering PLTs in a shorter timeframe may prove beneficial by possibly raising platelet counts to a higher level faster, and allowing patients to be disconnected from IV pumps sooner.

OBJECTIVE

To evaluate the optimal (safe and effective) transfusion time by comparing standard administration of PLTs over 2-4 h to the investigational administration of PLTs over 30-45 min in the pediatric hematology-oncology inpatient population.

METHODOLOGY

A pilot trial was conducted using a convenience sample of hematology-oncology children. Children prescribed a PLT transfusion while admitted to an inpatient unit were eligible. If randomized to the intervention group, the nurse administered the PLTs over 30-45 min. If randomized to the standard group, the nurse administered the PLTs over 2-4 h. Post transfusion PLTcount was drawn 30 min after completion. The child was monitored closely for adverse reactions.

RESULTS

Eleven participants were enrolled in the study and 20 PLT infusions administered. No adverse events were noted. There was not a significant difference in changes in PLT counts by group (post minus pre), p = 0.082. There was not a significant difference in post infusion PLT counts, p = 0.727. There was a significant difference in the rate of change in PLT counts by groups, p = 0.003.

NURSING IMPLICATIONS

This pilot study provides preliminary evidence that PLTs may be safely and effectively administered over 30-45 min in pediatric hematology-oncology patients. With quicker PLT administration, patients can be disconnected from IV pumps sooner.

Consensus Report by the Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplant Consortium Joint Working Committees on Supportive Care Guidelines for Management of Veno-Occlusive Disease in Children and Adolescents: Part 2-Focus on Ascites, Fluid and Electrolytes, Renal, and Transfusion Issues

Even though hepatic veno-occlusive disease (VOD) is a potentially fatal complication of hematopoietic cell transplantation (HCT), there is paucity of research on the management of associated multiorgan dysfunction. To help provide standardized care for the management of these patients, the HCT Subgroup of the Pediatric Acute Lung Injury and Sepsis Investigators and the Supportive Care Committee of the Pediatric Blood and Marrow Transplant Consortium, collaborated to develop evidence-based consensus guidelines. After conducting an extensive literature search, in part 2 of this series we discuss the management of fluids and electrolytes, renal dysfunction; ascites, pleural effusion, and transfusion and coagulopathy issues in patients with VOD. We consider the available evidence using the GRADE criteria.