Bleeding Disorders By Dr Haider Al Shamaa

1. Bleeding Disorders By Dr Haider Al Shamaa

2. Bleeding disorders Bleeding disorder classifying to: 1-vascular walls alterations:This due scurvey, infections, allergy or autoimmune diseases, and hereditary defects of collagen fibers. 2-Thrombocytopenia purpura:The total number of circulating platelets is reduced below 60.000-80.000/mm3 (normally 150.000-450.000/mm3).The patient has petechial hemorrhage or purpura under the skin or mucous membrane even with slight trauma and ecchymosis (bigger than purpura) may be developed. Thrombocytopenia may be: a) Primary: Due to an unknown cause. b) Secondary: Due to systemic diseases as in leukemia, hyperspleenism caused by portal hypertension secondary to liver disease (because increased platelets destruction), Chemicals as in cytotoxic drugs, and in radiation (destruction of bone marrow). The platelets are derived from bone marrow megakaryocytes and then circulate in the blood .One third will be sequestrated or destroyed in the spleen. Their half life is 7-10 days.

3. 3-Disorders of platelets function (defective platelets):Because of genetic defect as in von Willebrand disease, Drugs as aspirin, Allergy or autoimmune diseases. 4-Disorder of coagulation:It could be either: a)Inherited as hemophilia and Christmas disease. b) Acquired: They are the most common causes of prolonged bleeding and include: 1-liver diseases :As the liver produced all the coagulation factors except factor number VIII which is doubtful in its origin and von Willebrand factor which is produced in epithelial cells. 2-VitaminK deficiency: caused by biliary tract obstruction, malabsorption syndrome and excessive use of broad spectrum antibiotics as vitamin K is needed by the liver to produce prothrombin and factor VIII, Ix, x. 3-Anticoagulant drugs: as heparin and aspirin.

4. Bleeding following extraction: Excessive bleeding may be caused by: 1-Bleeding disorder or hemorrhagic diseases. 2-Local factors:Which accounts for most of the cases as tearing of the gingiva during extraction, inflammation in the area or presence of pyogenic granuloma which is highly vascular granulation tissue and bleeding will not stop until we remove it; Damage of the blood vessel in the dental neurovascular bundle or of a major vessel if the incision is not planned well as of the facial artery during extraction of impacted lower third molar as it is only separated by the buccinators muscle.

5. Control of bleeding 1-Arrest the bleeding immediately by putting a pack. 2-clean the oral cavity of the patient by removing all the blood clots. 3-Examine the patient to see site of bleeding. If the bleeding is from large blood vessel we can ligate it but mostly is from capillaries so we can put in the socket surgicel or gel foam and support it by a matrice suture which will approximate the buccal and lingual mucosa and adapt the soft tissue on the bone and reduce bleeding. We can put iodoform pack which is a piece of gauze socked in iodoform but it is not absorbable and it has to be removed after 3 days.

6. Screening laboratory tests 1-Bleeding time:Tests adequate platelets function and also vascular phase, normally (1-6minutes) .It increases in decreased or abnormal platelets. 2-Partial throboplastin time (PTT):Measure the status of the intrinsic pathway and the common pathways of coagulation (blood still contained in the blood vessel). The normal range is (25-40 seconds). 3-Prothrombin time (PT):Measure the extrinsic and common pathways of coagulation. It is prolonged in factor VII deficiency while the PTT will increases in deficiency of factor VIII, IX, XI, XII. This test is done to evaluate the blood for its ability to clot. It is often done before surgery to evaluate how likely the patient is to have a bleeding or clotting problem during or after surgery. Normal PT Values: 10-12 seconds (this can vary slightly from lab to lab).

7. 4-Assay of clotting factors:The level of each clotting factor. The clotting time is not accurate because even if there is 5% of clotting factors in the blood the clotting time will be normal (2-5minutes). 5-International Normalized Ratio Blood Test-INR: Normal INR Values: 1 to 2 The INR is used to make sure the results from a PT test is the same at one lab as it is at another lab.and it is measured by the Formula: (INR= (PT patient/PT normal) ISI). PT patient = patient's measure PT (seconds) PT normal = laboratory's geometric mean value for normal patients (seconds) ISI = International Sensitivity Index

8. Dental management of patient on anticoagulant: Anticoagulants as warfarin and coumarine which are slowly acting are used in myocardial infarction, recent open heart surgery, prosthetic heart valve or deep venous thrombosis. Aspirin is also used because it interferes with adhesions of platelets. Heparin which is quick acting is usually used before renal dialysis. when subjected to minor oral surgery procedures. It can be concluded that the optimal INR value for dental surgical procedures is 2.5 because it minimizes the risk of either hemorrhage or thromboembolism. Nevertheless, minor oral surgical procedures, such as biopsies, tooth extraction and periodontal surgery, can safely be done with an INR lower than 4.0.

9. 1-Monitoring such patient is by prothrombin time. 2-If the patient prothrombin time is more than double the control ,then we must reduced the prothrombin time by referral to hematologist and not stop the drug because it may cause rebounding(immediate stop causes thrombosis) ;the control is done either: a) Gradual reduction of dose. b) Stop the drug and after 2days do the dental treatment after checking the prothrombin time and then return to the drug. 3-We must understand why the patient is taken anticoagulants. 4-Local anesthesia is safe infiltration or block provided we take local measures to control blood loss.

10. 5-Extraction should be done with minimal trauma and then local measure for control of bleeding are carried out by putting a local haemostatic agent as surgicel or gel foam, but in normal extraction we never suture because it causes trauma to the soft tissue and bleeding, but when necessary we do it with minimal trauma. Sometimes an acrylic plate without clasps is prepared before the extraction and used not to arrest the bleeding but to protect the blood clot but if is constructed badly it may cause trauma and ecchymosis. 6-Prophylactic antibiotics to prevent postsurgical infection.