Blood coagulation time measurement - automatically stops timing device when pumped sample coagulation increases pressure

摘要

The apparatus for the measurement of coagulation time of blood or blood plasma uses the Quick principle. The timing counter is started automatically, and recognises the start of the coagulation process and then stops the timer. This arrangement eliminates possible errors due to human observation and stop watch on timing coagulation time. The reagent is automatically mixed with the blood or the plasma sample. The sample is pumped with small pressure variations while the sample is liquid. However, when the coagulation starts then the flow resistance will increase suddenly. A pulse is generated by the pressure gauge and this stops the timing instrument for indicating the Quick time.