Use of fresh platelet concentrate or lyophilized platelets in thrombocytopenic dogs with clinical signs of hemorrhage: a preliminary trial in 37 dogs

Abstract

Objective To examine the safety and feasibility of using lyophilized platelets (LYO) and fresh platelet concentrate (FRESH) in bleeding thrombocytopenic dogs. Design Preliminary prospective randomized clinical trial. Setting Two private referral centers and 3 university teaching hospitals. Animals Thirty‐seven dogs with a complaint of hemorrhage associated with thrombocytopenia (platelet count <70 × 109/L [70,000/μL], a hematocrit >15%, and that had received neither vincristine nor platelet‐containing transfusions within 72 h of enrollment were studied. Interventions Animals were randomized to receive LYOor FRESH, dosed according to weight. Physical examination, complete blood counts, and coagulation testing (prothrombin time and activated partial thromboplastin time) were performed at enrollment. Physical examinations were also performed immediately post transfusion, and at 1 and 24 h after transfusion. Complete blood counts were repeated immediately post transfusion and at 24 h. Collected data included bleeding score (BLS), response to transfusion, adverse reactions, hospitalization time, need for additional transfusions, survival to discharge, and 28‐d survival. Measurements and Main Results Twenty‐two dogs received LYOand 15 received FRESH. There was no difference between groups in age, weight, BLS, platelet count, white blood cell count, hematocrit, or presence of melena. There was no difference between groups in transfusion reaction rates, the need for additional transfusions, 24‐h BLS, hospitalization time, survival to discharge, or 28‐d survival. Conclusions Transfusion of LYO was feasible and associated with a low transfusion reaction rate in this limited study of thrombocytopenic canine patients presenting with mild‐to‐severe hemorrhage. LYOwere easy to use and provided storage advantages over FRESH. Further study of this product, including examination of efficacy and platelet life span, is warranted.

Platelet Disorders

“…When a patient with a known platelet disorder is presented to the emergency room or critical care unit, the treatment is based on the underlying cause of the defect in primary hemostasis. When a primary hemostatic disease is suspected because of a primary thrombopathy other than vWD, treatment should involve fresh platelet concentrates 38,39 or dimethyl sulfoxide cryopreserved platelets. Therefore treatment with fresh frozen plasma or cryoprecipitate would be efficacious.…”

Thrombocytopenia

“…62 Because of the shorter lifespan of lyophilized platelets (minutes), their indication is for arresting active hemorrhage rather than for preventing future hemorrhage or raising platelet count. A lyophilized canine platelet product, which can be stored at 4° C for up to 12 months, has been studied for canine patients.…”

“…Although the necessity for repeat platelet transfusions is uncommon in veterinary patients, leukoreduction of platelet products can remove the donor's antigen presenting cells (APC) and decrease the incidence of alloimmunization. 62,63 and the thrombopoietic agents, romiplostim (AMG 531) and eltrombopag, are recently developed treatments for chronic human ITP. 63 These are potential adverse reactions that may occur in veterinary patients and are manifested as an increase in body temperature more than 2° C, chills, dyspnea, cyanosis, bronchospasm, and extensive urticaria.…”

“…62 In dogs with ITP, which is the most common cause of severe thrombocytopenia, platelet transfusions are given uncommonly because of the belief that transfused platelets are marked rapidly for destruction, and the resultant increase in platelet count is negligible. 62 In dogs with ITP, which is the most common cause of severe thrombocytopenia, platelet transfusions are given uncommonly because of the belief that transfused platelets are marked rapidly for destruction, and the resultant increase in platelet count is negligible.…”

Platelet-mimetic strategies for modulating the wound environment and inflammatory responses

“…However, platelet transfusion is limited by the relative lack of donors, storage cost, and short shelf life of donated platelets, and the fact that most platelet therapy is done prophylactically rather than therapeutically. 40,41 The short shelf life of stored platelets makes the development of new therapeutic natural platelet-based technologies difficult. 42 Even though recent technologies have improved the shelf life of natural platelets to up to seven days, this shelf life does not allow for a ''bank'' of platelets to be generated, which may be necessary for therapeutic applications requiring large volumes of platelets; furthermore, stored platelets are placed at an increasing risk of bacterial contamination that could result in a severe immunologic response if used in a transfusion.…”