Plateletcrit and absolute immature platelet count are not impacted by platelet transfusions: a single-centre prospective study.

Background: This is the first study in which the impact of platelet transfusions on seven platelet indices was evaluated in platelet transfusion-dependent patients admitted in the ICU.

Study design and methods: Among a cohort of 21 ICU patients prospectively studied over eleven months, a total of 19 ICU patients were enrolled. Seven platelet indices were measured before and then, within 18-24 h, after platelet transfusions using the Sysmex XN-10 analyser and statistically investigated as follows: i) apheresis vs. pooled platelet transfusions; ii) pre- vs. post-platelet transfusions; and iii) platelet count (PC) increment vs. PC decrement group.

Results: A 79.2% of platelet transfusion episodes in ICU patients showed an increase in PC increment within 18-24 h, of which 73.7% had a peak percentage immature platelet fraction (%-IPF) above 10.0% during their stay. No difference was observed in the measurements of platelet indices between the apheresis and pooled platelet transfusion doses (all p > 0.05). Of the seven platelet indices investigated, plateletcrit (PCT) and absolute immature platelet count (A-IPF) were not influenced by platelet transfusions and thus proven to be stable (0.06 vs. 0.07%, p = 0.0901 and 4.6 vs. 4.9 × 10⁹/L, p = 0.4559, respectively), despite their close proximity to platelet transfusion. But the overall effectiveness of these indices in detecting changes over time was not hindered.

Conclusion: A-IPF and PCT are stable after platelet transfusions, regardless of whether patient's respond to or do not respond to platelet transfusion doses. PCT and A-IPF may thus prove useful in monitoring patient transfusion support and guiding management in thrombocytopenic patients.