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Enrolling by invitation NCT05038722

Function of Platelets Used for Transfusions

Observational Thrombocytopenia Hematologic Malignancy

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Platelet transfusion.
Who it may be relevant to
Registry conditions: Thrombocytopenia, Hematologic Malignancy. Basic parameters: from 18 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Sweden
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Official title

Flödescytometrisk utvärdering av Den Blodstillande förmågan Hos Trombocyter Avsedda för Transfusion

Overview

Cytotoxic treatment for malignant hematologic disorders often casue thrombocytopenia that can result in life threatening bleedings. This is prevented by platelet transfusions but these can cause serious transfusion reactions and thus the number of transused platelet concentrates should be limited. It is therefore important that the platelet concentrates contain functional platelets with long circulation time in the bloodstream. We have developed a method with flow cytometry to measure platelet function markers. It allows us to determine which pathways that are initiated upon activation. The aim of this project is to assess to what degree spontaneous activation of platelets as well as their activation capacity affects the transfusion response (i.e. uptake in the circulation and circulation time) in the recipient. The hypothesis is that transfusion of platelets with low spontaneous activation and high activation capacity will lead to a higher transfusion response in the recipient.

Detailed description

Cytotoxic treatment for malignant hematologic disorders often casue thrombocytopenia that can result in life threatening bleedings. This is prevented by platelet transfusions but these can cause serious transfusion reactions and thus the number of transused platelet concentrates should be limited. It is therefore important that the platelet concentrates contain functional platelets with long circulation time in the bloodstream.

The role of platelets in hemostasis is complex. Upon vascular injury, platelets adhere at the injured site where they become activated, release their granule content and aggregate. Activation include changes in receptors, expression of activation markers and become procaoagulant. We have developed a method with flow cytometry to measures these platelet function markers. It allows us to determine which pathways that are initiated upon activation.

Platelets can be stored a maximum of 5-7 days before transfusion. However, the preparation process and subsequent storage can result in platelet lesions, affecting their ability to promote hemostasis and circulate after transfusion.

The aim of this project is to assess to what degree spontaneous activation of platelets as well as their activation capacity affects the transfusion response (i.e. uptake in the circulation and circulation time) in the recipient.

The hypothesis is that transfusion of platelets with low spontaneous activation and high activation capacity will lead to a higher transfusion response in the recipient.

We will be able to examine how this relates to platelet processing methods and storage duration.

Platelets will be transfused on normal indications to participants at the hematology ward. The platelet concentrates choosen to be transfused will be done according to regular routines at the blood center. We will thus not control what concentrates are transfused (i.e. preparation method and storage time) and hence included in the study.

A small sample will be taken from the platelet concentrate shortly before transfusion and platelet function analysed with the flow cytometry method. Transfusion response will be assessed in the participant by calculation of corrected count increment (CCI) which relates the increase in platelet concentration after transfusion to the number of platelets transfused and the blood volume. CCI is calculated at 1 and 24-hours after transfusion. Clincial variables that might affect the transfusion response such as infection and fever will be registered as well as bleeding. The number of days to next platelet transfusion will be followed up.

Interventions

  • Other Platelet transfusion
    Transfusion of platelet concentrates according to routine practice.

Primary outcome measures

  • Corrected count increment (CCI) [Time frame: 1- and 24 hours after transfusion.]
  • Spontaneous and agonist induced expression of platelet activation markers on platelets in platelet concentrates. [Time frame: Measured on the day of transfusion prior to transfusion.]
  • Spontaneous and agonist induced formation of platelet subpopulations in platelet concentrates. [Time frame: Measured on the day of transfusion prior to transfusion.]
Secondary outcome measures (5)
  • Treatment of infection. [Time frame: Prior to transfusion.]
  • Signs of infection - fever. [Time frame: Prior to transfusion.]
  • Bleeding. [Time frame: Prior to platelet transfusion and 24-hours after the transfusion.]
  • Number of platelet transfusions [Time frame: From beginning of the cytotoxic treatment cycle to inclusion in the study, i.e receiving a study concentrate.]
  • Days to next platelet transfusion. [Time frame: After the study platelet concentrate was transfused, followed for up to two weeks after transfusion.]

Eligibility criteria

Inclusion criteria

  • Participant undergoing treatment for malignant hematologic disorders
  • Thrombocytopenia
  • Require platelet transfusion

Exclusion criteria

\- Participant requiring HLA-matched platelet transfusions.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model
Cohort

Study locations

Sweden · 2 centers
  • Region Östergötland — Linköping
  • Örebro University — Örebro

Identifiers

NCT: NCT05038722 · 2020-05968

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗