Duration of anticoagulant application: 3-6 months of anticoagulation after biological flap replacement, if there is atrial fibrillation, huge left atrium can extend the anticoagulation time appropriately, after mechanical flap replacement requires lifelong anticoagulation. Anticoagulation criteria and monitoring: Insufficient anticoagulant dosage has the risk of thrombosis and embolism, while overdose of anticoagulant has the risk of bleeding, so correct anticoagulation is very important. Insufficient or excessive anticoagulation can threaten your health and life!
Normal value: prothrombin time (PT) 12 – 14 seconds. The correct standard for anticoagulation is a PT of
The correct standard for anticoagulation is a PT of 1.5 – 2 times the normal value (21 – 28 seconds) and an International Normal Ratio (INR) of 2.0 – 3.0. For proper anticoagulation, blood should be collected frequently for testing,
To adjust the dosage, blood tests should be taken frequently. During the period of finding the appropriate dose (i.e., during the period of finding the dosing pattern). Generally, blood tests should be performed every other day after surgery, and once every 2 weeks after discharge from the hospital, or once every 4 weeks if repeatedly measured 2 times. Dosage adjustment: (1) Generally, the first oral dose is 1 tablet of warfarin (2.5mg for domestic warfarin, 3.0mg for imported), and one tablet daily thereafter, adjusted according to the laboratory results and the presence of bleeding signs. (2) Inadequate anticoagulation: 1/4 tablet of warfarin can be added, while continuing to monitor and gradually increase the dose until the standard is reached. (3) Anticoagulation overdose: If the prothrombin time exceeds 2.5 times normal, the dosage can be reduced by 1/4, while continuing to monitor and gradually reduce the dosage until the standard is reached. No bleeding tendency can be closely observed, and if there is bleeding tendency, inject vitamin K1 immediately to counteract it. And immediately contact with the hospital. (4) Pay attention to any bleeding tendency, often manifested as epistaxis, gum bleeding, blood in urine, intra-abdominal bleeding manifested as abdominal pain, intracranial bleeding manifested as coma, etc. If there are signs of bleeding, the dose should be reduced or suspended even if the test is in the appropriate range. And immediately contact with the hospital. (5) Pay attention to the presence of thrombosis and embolism: the cause of thrombosis is related to the valve material and structure in addition to insufficient anticoagulation, and the valve acoustic changes can be heard for a long time after thrombosis, and patients feel easy fatigue, chest tightness, shortness of breath, palpitations and other discomforts, and in severe cases, heart failure and even death; such as cerebrovascular embolism, neurological symptoms include confusion, hemiparesis, etc. Limb artery embolism appears as limb pain. Any suspected thrombosis requires immediate hospital consultation. Anticoagulant maintenance dose: general maintenance amount of warfarin is about 2.5mg/day, but due to individual differences, the required dose is different, clinical observation requires up to 7mg/day, and at least only 0.5mg/day. Be sure to have regular blood tests for the four coagulation tests as ordered by the cardiac surgeon. Treatment of bleeding complications: (1) Minor bleeding: such as gum bleeding, skin bruising can be reduced by 1/4 tablet of warfarin according to the laboratory results, while continue to closely observe and continue to reduce the dosage if necessary. (2) Obvious bleeding: such as epistaxis, hematuria can stop using warfarin for 1 or 2 days. (3) Severe bleeding: such as hemoptysis, vomiting of blood, intracranial hemorrhage, immediate sedation of vitamin K1 20mg, observation for 1-2 days after the bleeding stops, and re-anticoagulation. (4) Fresh frozen plasma or coagulation factor concentrates should be used in critical cases to supplement coagulation factors. (5) Do not forget to contact the surgical hospital. Anticoagulation during menstruation: Most people do not have a lot of menstruation, the amount of anticoagulants used can be maintained; if the bleeding increases, the amount of warfarin can be reduced, if there is a lot of bleeding, vitamin K can be injected to stop the bleeding, if the menstrual bleeding is disordered and the bleeding continues, menstrual regulating drugs should be taken; in rare cases of heavy bleeding, hysterectomy is required. Treatment of surgery during anticoagulation: With the aim of surgery not causing excessive blood loss, the following methods can be used: (1) Non-stop anticoagulation: minor surgery with little bleeding or that can be stopped by compression can be non-stop anticoagulation, such as removal of small masses on the body surface and debridement. (2) Maintenance of anticoagulation: anticoagulation can be postponed when emergency surgery is required for those who have not started anticoagulation recently after surgery, such as tracheotomy, no tendency to continue bleeding after emergency surgery, anticoagulation should be started as early as possible. (3) Discontinuation of anticoagulation: When emergency surgery is required, blood should be collected immediately to measure prothrombin time and activity, and vitamin K1 should be injected sedately at the same time.
If time is of the essence, the operation can be started without waiting for the laboratory results and after injecting vitamin K1, and the anticoagulation can be started 24-48 hours after the bleeding has stopped. (4) Suspension of anticoagulation: stop warfarin 3-5 days before surgery and operate after normal laboratory tests, or stop warfarin 5 days before surgery and inject heparin, and stop heparin 4-6 hours before surgery.