• Korean Journal of Clinical Laboratory Science
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• v.41 no.1
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• pp.1-5
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• 2009

The Platelet Function Analyzer (PFA)$^{(R)}$-100 measures the ability of platelets activated in a high-shear environment to occlude an aperture in a membrane treated with collagen and epinephrine (CEPI) or collagen and ADP (CADP). The time taken for the flow across the membrane to stop (closure time, CT) is recorded. The aim of this study was to assess the potential of the PFA$^{(R)}$-100 as a primary clinical screening tool using the wide spectrum of clinical samples assessed for platelet function as well as to perform the optimal algorithm for the use of PFA$^{(R)}$-100. We established the reference interval in 460 hospital inpatients defined as having normal platelet function based on classical laboratory tests. The reference interval by using the range $5^{th}$ and $95^{th}$ percentile was 84~251 seconds for males CEPI-CT and 85~249 seconds for females CEPI-CT. A total of 1,200 inpatients were enrolled to identify impaired hemostasis before surgical interventions. The abnormal group showing prolonged CEPI-CT was 303 cases (18.9%). Only 3 cases had both abnormal CEPI-CT and CADP-CT. Several factors including sample errors, drugs, hematologic abnoralities were contributed to unexpected prolonged CEPI-CT for screening test. The von Willebrand factor (vWF:Ag) assay was performed only in one patient to verify the algorithm for the use of PFA$^{(R)}$-100. The PFA$^{(R)}$-100 was sensitive and rapid method for primary screening test of platelet dysfunction, so we can substitute it for the bleeding time in routine clinical practice.

• Journal of Veterinary Clinics
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• v.40 no.5
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• pp.330-335
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• 2023

Platelet function evaluation by PFA-100 or -200 has been known to be objective and sensitive for assessing platelet function and dysfunction of Von Willebrand Factor in humans and dogs. However, using the C/EPI cartridge in dogs is controversial. This study aimed to establish a reference range for PFA closure time in healthy small breed dogs (body weight < 10 kg) and to evaluate the effectiveness of both C/ADP and C/EPI cartridges for these dogs. Citrated blood samples were collected from 50 clinically healthy small breed dogs that were admitted for presurgical procedures or health checkups, and closure times were measured using the PFA-200. Reference ranges were determined as 42-144 s (median 67 s, mean 71.2 s, SD ± 21.2 s, 95% RI 43-140 s) , for CT-C/ADP and 41-200 s (median 87, mean 91.2 s, SD ± 31.8 s, 95% RI 44-195 s) for CT-C/EPI. The present study demonstrated that the reference ranges for PFA closure times in small breed dogs are in line with existing reference ranges. The utilization of C/ADP cartridges is the preferred choice for evaluating platelet function in small breed dogs. However, due to variable responses of epinephrine to platelet aggregation in dogs, caution should be exercised when using C/EPI cartridges.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.2
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• pp.153-161
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• 2021

Objectives : The purpose of this study is to compare bleeding tendency of selective serotonin reuptake inhibitor (SSRI) and serotonin norepinephrine reuptake inhibitors (SNRI) using platelet function analyzer (PFA-100) in patients with major depressive disorder. Methods : This study is a prospective open-label study conducted by a single institution. A total of 41 subjects diagnosed with major depressive disorder under the DSM-5 diagnostic criteria participated in this study. The subjects were classified into SSRI (escitalopram) groups and SNRI (duloxetine) groups, respectively, according to random assignments. The closure time (CT) was measured using a platelet function analyzer (PFA-100) before each antidepressant was administered and after 6 weeks. Paired-sample t-test was conducted within each group to determine whether a specific antidepressant had an effect on closure time. In order to confirm the relative change in platelet function between the two groups, an independent sample t-test was conducted to compare and analyze the change in closure time between the two groups. Results : There was no significant changes in closure time (CEPI-CT, CADP-CT) before and 6 weeks after drug administration in the SSRI and SNRI groups, and there was no difference in the amount of changes in closure time between the two groups. Conclusions : Our results showed no difference in bleeding tendency between SSRI and SNRI. This study suggests that further large-scale studies on bleeding tendency for various antidepressants are needed in the future.