Intravascular and total body platelet equilibrium in healthy volunteers and in thrombocytopenic patients transfused with single donor platelets

Abstract

Instrument platelet counts used in corrected count increment (CCI) and percent platelet recovery (PPR) formulas presume the transfused platelets are in equilibrium during the first hour after platelet transfusion. The timing of the pre-transfusion count affects CCI results, and we postulate that timing of CCI post transfusion affects CCI results. Platelet equilibrium using indium-111 platelet transfusions has not been reported. Platelet redistribution was studied in 16 healthy volunteers and 12 thrombocytopenic patients by generally infusing less than 72-hr stored single-donor platelets along with an aliquot of indium-111-labeled platelets by intravenous push. Counts were measured at 10, 15, 20, 60, and 120 min, and 24, 48, 72 hr along with continuous body scanning for 2 hr in healthy volunteers, and static organ scanning in patients and volunteers. Results indicated transfused platelets do not reach intravascular equilibrium for 60 min post-infusion and that the 10-min count cannot detect platelet refractoriness. However, total body equilibrium varies considerably between normal volunteers and thrombocytopenic patients. It is recommended to continue with the 1-hr post transfusion count. Am.

Platelet transfusion refractoriness

“…One‐hour post‐transfusion counts are difficult to obtain for logistical reasons in busy hospitals, so some have advocated using 10‐min post‐transfusion counts, which can be more easily obtained and yield similar results (O’Connell et al , 1988). By using radioactively labelled platelets to study the rate of equilibration post‐transfusion, platelets were found to require at least 1 h to reach intravascular equilibrium, thus suggesting that a 1‐h post count should be used (Brubaker et al , 1998). Usually, platelet refractoriness is not suspected unless routine platelet counts performed 16–24 h post‐transfusion fail to rise adequately.…”

“…A comparison of the 1‐h and 20‐h CCI as a predictor of refractoriness shows a reasonably good correlation ( r = 0·67) with the 20‐h CCI roughly 64% of the 1‐h CCI (Bishop et al , 1991). Some have argued that the timing of the post‐transfusion platelet count can help determine the cause of refractoriness, with poor 1‐h counts associated with alloimmunization (Daly et al , 1980; McFarland et al , 1989; Brubaker et al , 1998). However, there is too much variability in these studies and exceptions occur where alloimmunization takes up to 24 h to manifest (Kickler et al , 1985), making it difficult to determine cause based solely on the timing of platelet disappearance.…”

Management of Bleeding Complications of Hematologic Malignancies

“…Blood should be obtained 1 hour and 24 hours after transfusion; if there is no increase at 1 hour, alloimmunization or hypersplenism is suspected. 8 If there is a satisfactory increase at 1 hour but the count is back to baseline at 24 hours, fever, infection, or consumption is suspected. Platelet consumption may be due to continued bleeding, as from peptic ulceration, or secondary to DIC associated with sepsis and endotoxemia, or from release of tumor procoagulants (which often occurs in patients with acute promyelocytic leukemia).…”

Efficacy of prophylactic transfusions using single donor apheresis platelets versus pooled platelet concentrates in AML/MDS patients receiving allogeneic hematopoietic stem cell transplantation

“…18 PPC and SDAP were separated in groups, according to the sample collection time -1 h after the transfusion, 1 to less than 18 h and 18-24 h. The following cut-offs were used to classify the transfusions as refractory: 5.5 for the first-hour sample, 5.0 for the group collected between 1 and 18 h and 4.5 for the group collected with 18 h or later. 19 We evaluated the number of products that each patient had been exposed to before each platelet transfusion, and also…”