Platelet coagulation instrument CHRONO-LOG540, is the first platelet coagulation instrument introduced in Laiwu area and surrounding areas, this instrument is the original U.S. imported platelet coagulation instrument, supporting reagents, consumables are produced in the United States, can carry out platelet function testing in both whole blood and platelet-rich plasma mode, with fast, economic, simple operation, highly It is fast, economical, easy to use, highly sensitive and has a wide range of applications.
It can be used for preoperative platelet function testing to prevent intraoperative bleeding. Health check-ups to detect hypercoagulable blood. Detection of anti-platelet drugs. Detection of the efficacy of taking blood-activating herbs, hypertension, diabetes, hyperlipidemia, should be tested regularly.
1.Concept
Platelet aggregation (PAg) refers to the adhesion between platelets and platelets, showing the characteristics of activated platelets interacting and aggregating into clusters. This phenomenon can be induced by continuous agitation of platelet-rich plasma (PRP) or whole blood (WB) with the addition of aggregating agents (also called inducers).
2.Specimen collection
The general principle of blood collection should be smooth, not repeated puncture, blood collection is not smooth, easy to activate coagulation factors, or activate platelets, affecting the cohesion of platelets, specimens from collection to the completion of the operation within 3 hours, placed too long to reduce the strength and speed of platelet aggregation. Blood was collected in two tubes of 4 ml with anticoagulation tubes with coagulation blue caps, and immediately mixed gently upside down for at least 5 times, not too vigorously to prevent and control activation of platelets. (i.e. use 3.2% sodium citrate mixed 1:9 with blood)
(1) Diet: Fasting or no high-fat food for 12 hours before blood collection.
(2) Tobacco and alcohol are prohibited within 12 hours before blood collection.
(3) Drugs: No aspirin for one week; no drugs affecting platelet function for three days, such as pansentin, anti-inflammatory pain, vitamin E, vitamin B6, aminophylline, vasodilators (sodium nitroprusside, nitroglycerin, sodium nitrite), tretinoin, tachyphylaxis, diuretic, aminephrine, fenagan, phenazopyridine, anthromycin, penicillin, carbenicillin, furatantin, vipers, fibrinolytics ( Svate), Danshen, Chuanxiong, Radix Paeoniae, Safflower, Angelicae Sinensis and other herbs to activate blood circulation and resolve blood stasis.
(4) Need to be in a quiet state before blood collection, exercise can make platelets activate.
(5) Pay attention to the influence of physiological factors such as age, menstruation, and pregnancy. Menstruation and pregnancy, estrogen has influence on aggregation and release function, such as the second phase speed up in pregnancy, while the second phase caused by ADP and epinephrine is common during ovulation, while it is rare during menstruation and luteal phase.
3. Precautions for opening the application form
The application form should indicate the diagnosis of the disease, such as the use of anti-platelet drugs, the type of use and the dosage should be indicated. If the results do not match with the clinical, please contact promptly for re-collection of blood and retesting to find out the cause.
4.Normal value
The maximum aggregation rate of platelets
Adenosine diphosphate ADP (5.0UMOL/L) 69–88%
Adenosine diphosphate ADP(5.0UMOL/L)1-17Ohms
Collagen COLL(2mg/L) 70–94%
Collagen COLL (2 mg/L) 15–27 Ohms
Arachidonic acid AA ( 0.5 mmol/l) 74–99%
Arachidonic acid AA ( 0.5mmol/l)5–17 Ohms
Ristomycin RIS ( 1.0 g/l) >5 Ohms
5.Clinical significance
(1) Detection of hereditary platelet defect disease Examination according to different inducers
ADP
COL
AA
RIS
evidence of platelet incompetence
↓
↓
↓
N
macroplatelet syndrome positive
N
N
N
↓
platelet storage pool defect
↓
N
N
peanut tetracytic acid metabolic syndrome positive
↓
cannot be induced
cannot be induced
N
(2) Acquired functional defects Uremia MDS Cirrhosis
(3) Antiplatelet agents
(4) Pre-thrombotic state Infarction Cerebral thrombosis Angina pectoris Hypertension Diabetes mellitus Hyperlipidemia Increased platelet coagulation induced by ADP COLL AA, also significantly increased by low concentration of inducing agent
(5) When choosing induction agents, use low concentration of induction agents for hypercoagulation and high concentration of induction agents for platelet defects
(6) The use of ASA is more sensitive than the use of AA induction agent.
(7) VWD is a defect in platelet adhesion response caused by plasma VWF factor deficiency. In the presence of VWF and GPIb receptors, Ris induces platelet adhesion when platelets do not aggregate in response to Ris.
In the presence of VWF and GPIb receptors, Ris induces platelet adhesion, and when platelets do not respond to Ris aggregation, VWD disease or GPIb receptor deficiency is suggested. However, the prolonged interval between the two phases indicates an abnormal specimen. Ris of 0.3ng/ml can be used to differentiate.
6. Selection of inducers for antiplatelet therapy drugs
Classification of antiplatelet drugs
(1) drugs that inhibit the metabolism of arachidonic acid phosphodiesterase A2 inhibitors: atropine hydrocortisone, etc.; cyclooxygenase inhibitors: aspirin indomethacin pterostilbene
(2) phosphodiesterase inhibitors cilostazol dipyridamole theophylline
(3) ADP receptor antagonists clopidogrel ticlopidine adenosine
(4) Adrenergic receptor antagonists Phentolamine Propranolol
(5) Thrombin antagonist Heparin
Our laboratory in the selection of inducers is based on the clinical choice of which antiplatelet drugs, we routinely choose arachidonic acid, collagen.
7.Clinical application
(1) Routine screening can be used for health checkup, screening out platelet hypercoagulable patients, can be carried out with lipid blood glucose, blood rheology as routine examination, clinicians according to the clinical comprehensive analysis to give with lipid lowering and hypoglycemia, the application of anti-platelet drugs, clinical has proved that anti-platelet drugs can significantly reduce the incidence of coronary heart disease, cerebrovascular disease, and peripheral artery thrombosis.
(2) Hypertension, diabetes, cerebrovascular disease, hyperlipidemia, ischemic encephalopathy, nephrotic syndrome, gestational hypertension, diabetes, should be tested regularly
(3) Preoperative testing. When platelet coagulation is significantly reduced, or taking aspirin, there is a risk of intraoperative bleeding if platelet coagulation is significantly reduced.
(4) antiplatelet drug efficacy testing, taking aspirin, often choose ADP and combined, after taking ASA arachidonic acid-induced platelet aggregation rapidly decreased, or even to zero, while ADP-induced platelet aggregation is only down to 50% showing that the drug inhibits platelets to the maximum extent, such as after review to confirm the arachidonic acid-induced coagulation rate did not decline, clinical should be considered aspirin resistance , clinical treatment is ineffective.
Small doses of aspirin 80-325 mg / day , bimatoprost need not be tested 150-200 mg / day When applied more than 250, the test is performed once a week, platelet aggregation so that it decreases 30-50% Platelets do not fall below 50 * 109, the application of arachidonic acid as an inducing agent.