Device of measuring a blood coagulating time

• US 5,114,860 A
• Filed: 02/08/1991
• Issued: 05/19/1992
• Est. Priority Date: 10/09/1984
• Status: Expired due to Term

• Current Assignee: Toa Medical Electronics Co., Ltd.
• Original Assignee: Toa Medical Electronics Co., Ltd.
• Inventors: Hayashi, Masayoshi
• Primary Examiner(s): McMahon, Timothy M.
• Application Number:
  US07/654,403
• Time in Patent Office: 466 Days
• Field of Search: 422/56, 422/68.1, 422/73, 422/82.09, 73/64.1, 436/69, 436/164, 356/39, 356/338, 356/341
• US Class Current: 436/69
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/56
• CPC Class Codes: G01N 33/86 involving blood coagulating time or factors, or their receptors

Abstract

A device of measuring a blood coagulating time, the device being constructed such that when the specimen is placed in a detecting section in which it is maintained at a desired temperature, the measuring initiation time is set, followed by the transmission of a series of measuring data to a memory through an arithmetic circuit until a saturation is reached in response to which the measuring operation is stopped. On presumption that the saturating value is 100%, arithmetic operation is conducted, the results of which are stored in the remaining space of the memory. The device includes a keyboard switch whereby a time corresponding to particular percentages, such as 20%, 50%, and 80%, is previously set so as to enable the time to be easily recognized and accurately reproduced.

Claims

1. A device for measuring blood coagulating time comprising:

a detecting section for measuring coagulation of blood, said detecting section comprising an accommodator for housing a container containing a specimen of blood plasma, a cover for covering the accommodator against outside light , an optical unit for continuously measuring coagulation of said specimen of blood plasma and continuously generating first output signals which are transmitted from said detecting section, said optical unit including a source of light and a light receiver located beside the container and a thermal controller whereby the specimen in the container is maintained at a desired temperature;

a pipette including a switch whereby the measuring of time for the specimen of blood to coagulate is started by activating said switch;

a detector means for receiving the first output signals from the detecting section and generating second output signals;

a keyboard switch by which items to be measured and desired conditions are input to said device;

an arithmetic means for comparing successive second output signals from said detector means, said arithmetic means connected to the pipette, the keyboard switch, the detector means, and the thermal controller;

a memory means for storing second output signals, said memory means connected to the arithmetic means;

a display screen means connected to he arithmetic means, said display screen means for generating in-process graphs of coagulation measurements; and

a recording section connected to the arithmetic means, said arithmetic means connected to said pipette such that when said switch in said pipette is turned on a signal is sent to said arithmetic means to start timing a blood coagulating time, said arithmetic means connected to said detector means such that second output signals are continuously transmitted to said arithmetic means and stored in said memory means, said arithmetic means comparing each successive second output signal, transmitting a signal to the detector means so as to stop the measuring of blood coagulation when a saturation value is reached, the saturation value being obtained when said second output signals from the detector means remain constant, and said arithmetic means conducting an arithmetic operation on a presumption that the saturation value is 100% thereby determining blood coagulating time by calculating a percentage between 20% and 80% predetermined by the keyboard switch.

2. A method for measuring blood coagulation time comprising the steps of:

(a) combining blood plasma and a reagent in a container by means of a pipette, said pipette having a switch such that when the blood plasma and reagent are combined, the measuring of time for blood coagulation time starts;

(b) closing a cover on the container thereby covering the container against outside light;

(c) directing a light from a source of light through the combined blood plasma and reagent to a light receiver;

(d) generating output signals form said light reciter and feeding the signal to an arithmetic means;

(e) comparing successive output signals received by the arithmetic means;

(f) generating in-process graphs of said output signals with a display screen means;

(g) designating the output signal obtained in step

(e) as a saturated value when said arithmetic means determines that successive output signals remain constant; and

(h) designating the blood coagulating time as a period of time from when the blood plasma and reagent are combined until a predetermined percentage between 20% and 80% of the saturated value is obtained.