The Effect of Venous Occlusion on the Sequestration of Blood Platelets

1972 ◽  
Vol 28 (03) ◽  
pp. 383-392 ◽  
Author(s):  
J Hladovec ◽  
Z Koleilat ◽  
I Přerovský

SummaryThe venous occlusion of all four legs in rats caused a highly significant decrease of platelet counts in venous blood especially after the correction for an opposite change in haematocrit. A very pronounced decrease in platelets was observed in human volunteers after a venostasis in one arm in the blood drawn from the occluded limb just before the release of occlusion. Similar decreases were found after a venostasis of both legs in postocclusion blood samples. The decrease in blood platelets results from temporary sequestration in the occluded limbs. The decreases of platelets after a 10 min occlusion of both legs are more pronounced in patients with post thrombotic states.

Blood ◽  
1971 ◽  
Vol 38 (4) ◽  
pp. 422-430 ◽  
Author(s):  
GEOFFREY M. BRITTIN ◽  
SHIRLEY A. DEW ◽  
ELVI K. FEWELL

Abstract We have evaluated the use of an optical particle counter to perform automated platelet counts on whole blood. The erythrocytes were lysed by dilution of whole blood with 2 M urea and the remaining platelets and leukocytes were enumerated by a darkfield microscope optical system that detects light diffracted by them. A suspension of fixed human platelets available commercially was highly satisfactory for standardization. The method gave accurate and reproducible platelet counts, comparable with those of electronic particle counting on venous blood and substantially more reliable platelet counts on thrombocytopenic and finger-puncture blood samples. We believe that errors resulting from the electronic method were caused by technical difficulties of sample handling and not to an intrinsic error in electronic counting. By using the automated optical method we found no significant difference between the platelet counts of capillary and venous blood, although capillary platelet counts had twice the variability of venous counts. The optical technique has important advantages over electronic platelet counting, and its superiority appears to be due to the ability to count platelets in diluted whole blood rather than in plasma. It should prove especially useful in performing the large numbers of platelet counts on thrombocytopenic and finger-puncture blood samples that are increasingly important for management of patients receiving chemotherapy.


2016 ◽  
Vol 3 (2) ◽  
pp. 81
Author(s):  
Hieronymus Rayi Prasetya ◽  
Maria Irena Dentri ◽  
Sistiyono Sistiyono

Background: Platelets play a role in hemostasis which is the body's mechanisms to prevent and stop the bleeding. Platelets participate in the effort to close the wound, so that the body does not experience a loss of blood and protected from foreign cells. Examination of the platelet count is very important in the diagnosis of diseases, one of which is the diagnosis of dengue hemorrhagic fever (DHF). Examination of blood counts, especially platelets in clinical laboratories causes blood samples in use are not always the venous blood but could use capillary blood. Capillary blood samples are used primarily in pediatric patients, because the venous blood sampling is difficult, patient loads, and also shorten the time when taking blood. The purpose of this study was to determine whether there is a difference in counting the number of platelets using samples of blood veins and capillaries. Methods: Quantitative research with observational approach using a cross sectional study design in the 30 samples of student D3 Health Analyst STIKes To Nation Yogyakarta. Statistical methods in use are independent T test. Results: The research subjects were 30 samples of student D3 Health Analyst STIKes To Nation Yogyakarta. The results of the examination of venous blood platelet count and blood capillaries have different average values ​​are 247 530 cells / ml of blood, for blood platelets veins and 184 270 cells / ml of blood for capillary blood platelets. Spearman correlation analysis Obtained results of the examination of venous blood platelet count and blood capillaries normal distribution (p> 0.05). 0.129 venous blood platelet counts, while the number of blood platelets kapilernya 0.089. Conclusion: There is a significant difference from the results of counting the number of blood platelets using veins and capillaries, where the use of capillary blood samples showed that lower platelet counts.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256423
Author(s):  
William M. Dickerson ◽  
Rebecca Yu ◽  
Helena U. Westergren ◽  
Jonathan Paraskos ◽  
Philipp Schatz ◽  
...  

Background Point-of-care (PoC) testing of platelet count (PLT) provides real-time data for rapid decision making. The goal of this study is to evaluate the accuracy and precision of platelet counting using a new microvolume (8 μL), absolute counting, 1.5 kg cytometry-based blood analyzer, the rHEALTH ONE (rHEALTH) in comparison with the International Society of Laboratory Hematology (ISLH) platelet method, which uses a cytometer and an impedance analyzer. Methods Inclusion eligibility were healthy adults (M/F) ages 18–80 for donation of fingerprick and venous blood samples. Samples were from a random N = 31 volunteers from a single U.S. site. Samples were serially diluted to test thrombocytopenic ranges. Interfering substances and conditions were tested, including RBC fragments, platelet fragments, cholesterol, triglycerides, lipids, anti-platelet antibodies, and temperature. Results The concordance between the rHEALTH and ISLH methods had a slope = 1.030 and R2 = 0.9684. The rHEALTH method showed a correlation between capillary and venous blood samples (slope = 0.9514 and R2 = 0.9684). Certain interferents changed platelet recovery: RBC fragments and anti-platelet antibodies with the ISLH method; platelet fragments and anti-platelet antibodies on the rHEALTH; and RBC fragments, platelets fragments, triglycerides and LDL on the clinical impedance analyzer. The rHEALTH’s precision ranged from 3.1–8.0%, and the ISLH from 1.0–10.5%. Conclusions The rHEALTH method provides similar results with the reference method and good correlation between adult capillary and venous blood samples. This demonstrates the ability of the rHEALTH to provide point-of-care assessment of normal and thrombocytopenic platelet counts from fingerprick blood with high precision and limited interferences.


1979 ◽  
Author(s):  
B.R. Binder ◽  
J. Spragg

Following 15 minutes venous occlusion blood samples were drawn from human volunteers into EDTA and Polybrene as anticoagulants. The plasma of each donor (60-80mls) was fractionated by reverse (NH4)2SO4 gradient solubilization, elution from octyl-Sepharose with 50% ethylene glycol, and sequential gel filtration according to the method described for the purification of vascular plasminogen activator (Binder et al. JBC, 254, 1979, in press). A plasminogen activator (PA), demonstrately active on a plasminogen-rich but in active on a plasminogen-free fibrin plate, was purified by this procedure and characterized as having an apparent MW of 65.000-72.000, a pI of 8.0 - 8.3, and yielding a single protein stainable band on acid disk gels a t the region of PAactivity eluted from gels run in parallel. From the elution pat terns on the different columns used in the purification scheme, from the molecular weight value, the isoelectric point, and the mobility on acid polyacrylamide gels, it is concluded that the presently isolated and purified PA is identical to that already described as vascular plasminogen activator.


2015 ◽  
Vol 1 (2) ◽  
pp. 91
Author(s):  
Sujud Sujud ◽  
Ratih Hardiasari ◽  
Anik Nuryati

Pre-analytical phases is a very important stage and need to be considered properly. Pre-analytical phases of which is the process of blood sampling, sample delivery, the inclusion of the type of inspection, sample preparation and selection tools. A fact which still often the case that their neglect by nurses or laboratory personnel in taking and processing the blood samples. Blood samples for examination platelet counts as much as possible is done properly and the sample must be examined in less than 1 hour after taking blood. Delays checks can cause a decrease in platelet count. Delays often occur for over an hour due to the shipment of samples from wards that are not immediately performed or work shift lab personnel. The aim of research to determine the difference in the number of platelets in the blood EDTA is immediately checked and a delay of 1 hour by using KX-21 Hematology analyzer. Experimental study design with pre- and post-test study without control. The study was conducted at the Laboratory of RSJ Grhasia Yogyakarta, with the object of research is venous blood from patients RSJ Grhasia between the ages of 20-50 years of both men - men and women. Data were analyzed parametric statistical tests Paired samples t-test. The results of significant research value of the results of parametric statistical tests Paired samples t-test was 0,000 (sig <0.05). There is a difference between the number of blood platelets EDTA is immediately checked and a delay of 1 hour.


2018 ◽  
Vol 96 (3) ◽  
pp. 313-316
Author(s):  
Ronan M.G. Berg ◽  
Sarah Taudorf ◽  
Damian M. Bailey ◽  
Rasmus H. Dahl ◽  
Carsten Lundby ◽  
...  

The systemic inflammatory response triggered by lipopolysaccharide (LPS) is associated with cerebral vasoconstriction, but the underlying mechanisms are unknown. We therefore examined whether a 4-hour intravenous LPS infusion (0.3 ng·kg−1) induces any changes in the transcerebral net exchange of the vasoactive peptides endothelin-1 (ET-1) and calcitonin-gene related peptide (CGRP) and catecholamines in human volunteers. Cerebral blood flow was measured by the Kety–Schmidt technique, and paired arterial-to-jugular venous blood samples were obtained for estimating the transcerebral exchange of ET-1, CGRP, and catecholamines by the Fick principle in 12 volunteers before and after LPS infusion. The cerebrovascular release of ET-1 was enhanced, whereas the transcerebral net exchange of CGRP and catecholamines was unaffected. Our findings thus point towards locally produced ET-1 within the cerebrovasculature as a contributor to cerebral vasoconstriction after LPS infusion.


Blood ◽  
1965 ◽  
Vol 25 (2) ◽  
pp. 261-266 ◽  
Author(s):  
ROBERT I. WEED ◽  
S. LEE CRUMP ◽  
SCOTT N. SWISHER ◽  
Norma C. Trabold

Abstract 1. The addition of Na2EDTA (2.5 to 5 mg./2 ml. of whole blood) to dog or human blood samples has been shown to eliminate the problem of platelet clumping and to provide satisfactory samples for use in enumeration of blood platelets. The statistical errors of platelet counts in blood samples prepared with Na2EDTA agree well with previously published results obtained with unmodified technic. In blood samples prepared without Na2EDTA, where clumping is appreciable, the field error is inflated. 2. Variation in the time during which the platelets are permitted to settle in the chamber before counting, between limits of 30 and 90 minutes, has no effect on the count. 3. The period of standing of the diluted blood in 1 per cent ammonium oxalate, from 30 minutes to four hours, appears to have no effect on the out-come of the platelet counting results when the platelets are not clumped.


1989 ◽  
Vol 62 (04) ◽  
pp. 1107-1111 ◽  
Author(s):  
Hugo C Castro-Faria-Neto ◽  
Patricia T Bozza ◽  
Marco A Martins ◽  
Paulo M F L Dias ◽  
Patricia M R Silva ◽  
...  

SummaryThe injection of PAP (6 μg/kg, i. v.) induced, in rats, haemoconcentration accompanied by an increase in the platelet number, as attested by the counts of platelets in blood samples diluted in formalin-free EDTA solution. This increase was significant at 15 min, peaked from 1 to 4 h and returned to basal levels 24 h after the lipid administration. The release of platelets induced by PAP was inhibited dose-dependently by specific PAP receptor antagonists such as WEB 2086 (0.5-2 mg/kg), BN 52021 and 48740 RP (5-25 mg/kg). Furthermore, platelet mobilization was clearly impaired in splenectomized animals stimulated by PAP, whereas thrombocytopenia and haemoconcentration by the same stimulus were intact. It was also noted that a second injection of PAP, 24 h after the initial stimulation with the lipid, failed to induce an increase in platelet counts, indicating autodesensitization. Desensitization to PAP or pretreatment with PAP antagonists clearly prevented the increase in the platelet counts after stimulation by adrenaline (15 μg/kg). These findings suggest that, in rats, PAP can induce release of platelets by a spleen-dependent mechanism and that this lipid may be relevant to the thrombocytosis triggered by adrenaline.


1994 ◽  
Vol 72 (05) ◽  
pp. 672-675 ◽  
Author(s):  
Nicolas W Shammas ◽  
Michael J Cunningham ◽  
Richard M Pomearntz ◽  
Charles W Francis

SummaryTo characterize the extent of early activation of the hemostatic system following angioplasty, we obtained blood samples from the involved coronary artery of 11 stable angina patients during the procedure and measured sensitive markers of thrombin formation (fibrino-peptide A, prothrombin fragment 1.2, and soluble fibrin) and of platelet activation ((3-thromboglobulin). Levels of hemostatic markers in venous blood obtained from 14 young individuals with low pretest probability for coronary artery disease were not significantly different from levels in venous blood or intracoronary samples obtained prior to angioplasty. Also, there was no translesional (proximal and distal to the lesion) gradient in any of the hemostatic markers before or after angioplasty in samples obtained between 18 and 21 min from the onset of the first balloon inflation. Furthermore, no significant difference was noted between angioplasty and postangioplasty intracoronary concentrations. We conclude that intracoronary hemostatic activation does not occur in the majority of patients during and immediately following coronary angioplasty when high doses of heparin and aspirin are administered.


1965 ◽  
Vol 13 (02) ◽  
pp. 428-438 ◽  
Author(s):  
K Reber ◽  
A Studer

SummaryThis is a comparative study of the methods described by H. P. Wright and O’Brien for determining the adhesiveness of thrombocytes. An attempt is made to characterize and statistically correlate both techniques. With the aid of a Coulter Counter for thrombocyte counts, a normal range is presented for human, rat, and rabbit blood. Anticoagulants used are sodium citrate and Heparin.The influence of Cocaine and the Serotonin antagonist Ro 3-0837 was studied on these same substrates, to determine a pharmacological interference with results of either Wright’s test or O’Brien’s. Both drugs are found to induce a statistically significant increase in the “thrombocyte count” as compared to the corresponding controls. These effects are not real but to be attributed to an increase in particle count due to thrombocyte fragmentation as a consequence of drug application. There is no evidence for the claim that these drugs decrease the adhesiveness of thrombocytes.Numerical results of both tests often show a high and statistically significant correlation, especially following the addition of Ro 3-0837. Such is not true of individual blood samples to which no drug has been added. Evidentally, both tests are not specific for the same characteristic of normal blood platelets. But, when Ro 3-0837 is added, the breakdown of unstable platelets is induced; and the corresponding increase in count of thrombocyte fragments is expressed by both tests in the same fashion.


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