Comparison of the results of basic coagulation tests carried out in three different laboratories on the same sample of blood

Basic coagulation tests are carried out in every laboratory of hematology. Every patient who is about to undergo a surgery, or is treated with anticoagulants, should be examined this way. Coagulation tests allows to find out, if the patient is suffering from outer or from inner coagulation cascade disorder. Final diagnosis is carried out using specialized tests. The basic tests include protrombin time, activated parcial tromboplastin time, and fibrinogene. The principle of coagulation tests is determination of the time needed for detection of fibrin fiber after addition of reagent to the sample of tested plasma. Tests used in hemostasis can be global, group and specific. For the test, test tubes with an antikoagulant are used. In hemostasis, the antikoagulant used is trisodium citrate. It is always necessary to keep the same blood/citrate ratio. The preanalytical part, which consists of specific actions the sample undergoes from its obtaining to the analysis itself, is also very important. Nowadays, the coagulation tests are run in laboratories using multifunctional analysators. Blood samples are obtained from a vein. Small, portable coagulometers are used for measuring protrombin time for patients treated with anticoagulants. Blood for this test can be obtained from the fingertip. This thesis is focused on comparing the measurment of a sample on three different coagulometers. Different tromboplastins with different ISI (International Sensitivity Index) were used. Reagents for activated parcial tromboplastin time were also purchased from different producers. In this bachelor thesis, fifty randomly chosen samples were tested, because not every application form has the patients diagnosis stated. Every sample was tested that very day, within four hours from taking the blood. Samples were primarily tested in laboratory Synlab czech s.r.o., using coagulometer Sysmex CA. Other measurments were carried out in laboratory Stafila s.r.o. using coaguometer ACL Elite PRO and in laboratory Medipont s.r.o. using coagulometer START 4. All measurments were statisticaly evaluated. Average values and standard deviation were calculated, and shows, that the values does not differ significantly. Level of significance in INR test (international normalised ratio) and in activated parcial tromboplastin time was evaluated as statisticaly significant, yet without bigger clinical importance. Only in protrombine time, measured in seconds, results from coagulometers does not differ. The same can be applied when comparing coagulometers with each other. Based on my findings, it is recomended for the doctors to use the same laboratory for testing the protrombin time and activated parcial tromboplastin time. At the same time, it is necessary to say, that the differences measured in this thesis are so minor, that they have no practical clinical importance