Haemostasis is the process of forming clots in the walls of damaged blood vessels and preventing blood loss while maintaining blood in a fluid state within the vascular system.
Management of perioperative bleeding requires understanding and identifying patients at risk, recognition of hemostatic changes related to blood loss, injury, surgical procedures, institution of blood-based or pharmacologic interventions, and evaluation and understanding the results of coagulation tests for both acute and monitoring purposes.
In the modern era, it is now quite common to encounter patients on blood-thinning medications for the treatment of a variety of diseases. Common conditions for which patients take anticoagulants include various cardiovascular diseases, such as stroke, myocardial infarction, atrial fibrillation, and peripheral artery disease. Medications in these classes include warfarin (Coumadin), Lovenox, clopidogrel (Plavix), nonsteroidal antiinflammatories (NSAIDs), and aspirin. In the elective setting, a careful history and knowledge of the drug dosage allows for a thoughtful plan of medication discontinuation before surgery and a postoperative plan for restarting the medications.
When the anesthetist becomes face to face with coagulation disorder he must put in his mind that the solution of the problem may be easy just by stop of the causative drug taken is enough,but in some disorders intervention is needed as rapid as possible by used of transfusion of blood or blood component, specific coagulation factor replacement, vitamin k adminstration,antifibrinolytic drugs, or correction of the disease as in liver or renal failure.
The anesthetist must also choose the suitable type of anesthesia, drugs used and dealing with the patient by simple gentle maneuver to avoid trauma incidence to the patient.
Neuraxial anaesthesia or central neuraxial block (CNB) in the form of an epidural and/or a spinal block is increasingly used in various types of surgery to improve pain relief in the perioperative and postoperative periods.
For anaesthetists, one of the main concerns of performing CNB in patients receiving anticoagulation is bleeding into the spinal vertebral canal causing compression of the theca, which can potentially result in irreversible neurological damage and devastating paraplegia.
The most important part of the management process includes individualized preoperative assessment for the risks of thromboembolism in the absence of anticoagulation. Once the decision to perform CNB has been made, a number of key issues need to be addressed:
(i) a schedule for cessation of anticoagulation in order to achieve optimal haemostasis prior to catheter insertion/removal.
(ii) a safe interval for initiating thromboprophylaxis postoperatively.
(iii) postoperative surveillance for signs of spinal cord compression.
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