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Presented by :Wafa Ahmed Ehmoda Najla Mohammed Sasi
Bleeding disorders
Bleeding Disorder Def : Bleeding disorders is a general term for
a wide range of medical problems that lead to poor blood clotting and continuous bleeding.
characterized clinically by abnormal bleeding, which can either be spontaneous or become evident after some inciting event.
can result from : defects in the blood vessel abnormalities in the blood itself
blood clotting factor platelets
Source from : National Haemophilia Association
Etiology
I) PLATLETS DISORDER
II) VESSEL WALL ABNORMALITIES
III)CLOTTING DISORDER
i) PLATELET DISORDER, what is it?
WHAT IS PLATELETS ?
Oblong disk shape Size- 2-4 µm Produced in bone marrow by megakaryocte cell Platelet count in blood- 150,000-350,000 µL Life span- mean survival time (8_10) days Function :- a- Aggregation & adherence to injured vessel to
form primary clot (plug) b- help in clot formation
Platelets Disorders
Thrombocytopenia
ThrombocytosisPlatelet
dysfunction
THROMBOCYTOPENIA
Defined as reduced in the platelet count< 150, 000µL that
characterized by spontaneous bleeding, a prolonged bleeding
time, and a normal PT and PTT.
The risk of bleeding depends on the level of the platelet count:
Mild thrombocytopenia (platelet <150 000 cells/µL)
Moderate thrombocytopenia (platelet 20 000 - 50 000 cells/µL)
Severe thrombocytopenia (platelet <20 000 cells/µL)
Etiology:
I.Idiopathic (ITP):
a.Increased platelets destruction.
b.Decreased platelets production.
c.Both.
II.Secondary to:
a.Drugs induced thrombocytopenia→e.g (cytotoxic drugs)
b.Secondary to some diseases:• Bacterial or viral infection.• Uremia,SLE.• Neoplasia of bone marrow or lymphoid tissues
(leukemia,lymphomas).• Radiotherapy .
CLINICAL MANIFESTATIONS
Onset is usually sudden for acute ITP and in chronic ITP, it is insidious onset.
Petechiae or purpura Feet, legs, arms, and buttocks.
Mucosal bleeding. Palatal petechiae, epistaxis, hematuria,
menorrhagia, GI bleeding. Gingival bleeding
DIAGNOSIS
• History taking.• Physical examination.
o Signs of bleeding (petechiae and purpura). o Mucosal bleeding.
• Investigations.o Full blood count.
Low platelet count.o Histological findings.
Platelets are normal in size or may appear larger than normal.
Normal red blood cells morphology.Normal white blood cells morphology.
o Coagulation tests. Prolong bleeding time, normal PT and
PTT.
TREATMENT & MANAGEMENT
1.Remove the underlying cause if known.
2.Corticosteroids are useful in iodiopathic thrombocytopenia purpura (ITP) and in autoimmune drugs induced thrombocytopenia.
3.Splenectomy.
4.Platelets transfusion for secondary thrmbocytopenia.
5.Neumega is a new drug used to stimulate platelets in bone marrow.
Dental implication:
Gingival bleeding can be controlled by the use of fibrin foam,gel foam or absorbable cellulose with thrombin.
20 vol.hydrogen peroxide should be tried , in many cases it will control gingival oozing.
Elective dental surgery should be deferred.
Thrombocytosis thrombocythemia
There is increased number of circulating platelets , the elevation is in the range of 500,000_1000,000/cubic mm, but may be higher.
Etiology:
1.idiopathic.
2.secondary: may be secondary to ; Splenectomy. Myeloproliferative disease
Dental implication:
1.Dental treatment should be conservative, elective traetment should be delayed.
2.If there is gingival bleeding associated with gingivitis or periodontitis ,only scaling is performed to one quadrant per visit with extreme care to avoid inflicting trauma to the gingival tissue.
3.Hydrogen peroxide (20 vol.)and local hemostatic agents should be tried to stop gingival bleeding.
4.If extraction is unavoidable , pack the socket with gel-foam which is usually sufficient to stop the bleeding.
5.The dental management is complicated by hemorrhage, thrombosis and cytotoxic agents.
Disorder Of Platelets Function•Congenital platelets disorders ↓↓↓•Defect in adherence :-
>Bernard-Soulier syndrome• The glycoprotein (Ib) receptor for VIII:Vwf
is absent on platelet membrane.• Rx: platelets transfusion.
•Defect in aggregation :-
>Glanzmann thrombasthenia the platelets lack surface glycoprotein
receptor(IIb,IIIa)necessary for binding fibrinogen(fibrinogen receptor)
• Bleeding time is prolonged
Disorder of platelets function
•Acquired platelets disorders ↓↓↓
1..Meloproliferative diseases
2.. UREMIA
3.. Dysproteinemia
4..Drugs (Aspirin _Clopidogrol)
II) Vessel WALL abnormalities
SCURVY INFECTIONS (measles, scarlet fever,
endocarditis,malaria) ALLERGY HEREDITARY HEMORRHAGIC TELANGIECTASIS
Heridetary hemorrhagic telangectsis Dominant inherited condition , there is a
telengectiasis and small aneurysms found on finger tips, face,nasal passages, tongue and GIT.
Small group of people develope pulmonary A/V malformation.
Pt either develops reccurent bleeding /epistaxis/iron def. anemia due to GIT bleeding.
Rx ↓ Iron therapy for blood loss. Local cautery/ laser therapy for single lesion from
bleeding (epistaxis).
Dental aspect:
Trauma should be avoided whenever possible. Lesions may occasionally interfere with periodontal
therapy or oral surgery and the bleeding can be treated by electrocoagulation, laser therapy, cryotherapy or resection.
Escharotic agents such as silver nitrate, 50% trichloroacetic acid and chromic acid are effective on only small bleeding points.
Sclerosing agents such as prophylaxis. Iron and folate therapy may be required if there is chronic
anemia. Non steroidal anti-inflammatory analgesics are
contraindicated because of the risk of gastrointestinal bleeding and effects on platlets function.
Vessel wall abnormalities Ehlers danlos disease : Congenital disorder of collagen synthesis in which
capillaries are poorly supported by collagen and ecchymosis are commonly observed.
III) Clotting disorder
• Haemophilia• von Willerbrand Disorder
Primary
(Inherited)
• Vitamin K Deficiency• Hepatic Failure• DIC
Secondary
(Acquired)
Haemophilia – overview
A group of blood disorders in which there is defect in clotting factors.
70% are X-linked recessive disorder. 30% spontaneous mutation.
The bleeding patterns of haemophilia are similar. Types :
A:Deficiency in factor VIII (classic haemophilia). B: Deficiency in factor IX (Christmas disease). C: Deficiency in factor XI.
Hemophilia A (classic or true hemophilia)
Definition:This is most common type of hemophilia ,it is
characterized by deficiency of factor VIII and prolonged (APTT).
Normal value of VIII is 50% _150%.
Normal value of (APTT) is 25 _40 sec.
Bleeding character in hemophilia:bleeding stop immediately after injury as a result of
normal vascular and platelets response but after an hour or more intractable oozing or rapid blood loss starts and persists.
Haemophilia - classificationClassification Clinical Manifestation
Severe(<1% of normal)
• Manifest in infancy when child reaches toddler stage• Spontaneous bleeding – in muscles or joints (haemarthroses)• Excessive bleeding after minor trauma, postoperatively, or after intramuscular childhood vaccinations.
Moderate(1-5% of normal)
• Manifest after 2 years of life• Moderate trauma causes bleeding episodes• Occasionally spontaneous bleeding occurs
Mild (>5% - <40% of normal)
• Often diagnosed in teenagers and adults• Significant trauma to induce bleeding• No spontaneous bleeding
26
Haemophilia – clinical manifestation Haemarthrosis (spontaneous bleeding
in muscle or joints - painful) Joint Swelling Easy bruising Epistaxis Haematuria Intracranial hemorrhage
Oral manifestations
1- bleeding from any site of oral cavity and sometimes it may cause respiratory obstruction.
2- gingival hemorrhage. 3- bleeding associated with physiological erupation. 4- tooth extraction or minor surgery may lead to sever
hemorrhage, sometimes may be fatal.
Dental management of hemophilia A
Prophylactic measures:- 1-regular dental care. 2- fluoride application. 3- sugar restriction. 4-prevention of periodontal disease. These measures reduce the need for extraction which
may be major hazard in hemophilia. Endodontics: reaming through the apex should be
avoided. Periodontal therapy: scaling can be performed(except
in sever hemophilia)under antifibrinolytic cover. Conservative dentistry: care should be considered to
avoid soft tissue trauma.
HAZARD OF ANASTHESIA :
Local and general anesthesia are hazardous in absence of factor replacement .
Anesthesia injection especially nerve block can be hazard particularly for severe hemophiliacs, bec the needle tear the wall of small blood vessels and a deep spreading hematoma can threaten the air way also the hematoma is formed during intramuscular injection so the best safer is nitrous oxide analgesia to avoid use of L.A.
MANAGEMENT OF EXTRACTION: 1-Laboratory tests : factor VIII should be raised to 50%_70%before
dental extraction and raised to 100% for major surgery. 2-postoperatively the patient should be hospitalised and factor VIII
should be given I.V. 3-antibiotic should be given to avoid the risk of infection. 4-aspirin should be avoided it may cause gastric bleeding so
parcetamol is better alternative.
Hemophilia B CHRISTMAS DISEASE
The disease is identical to hemophilia A but charaterised by deficiency of factor IX.
TREATMENT :-1- mild hemophilia B :- fresh frozen plasma is
adequate.
2-severe hemophilia B:-factor IX (I.V) 1hr preoperatively.
Von willebrand‘s disorder - overview
Most common hereditary deficiency caused abnormality in von Willerbrand protein.
Functions on both primary & secondary homestasis. 1. To act as bridge between subendothelial
collagen and platelets 2. Bind and protect factor VIII from rapid
clearance then delivers it to site of injury.
Von willebrand‘s disorder - types
Type 1 _ mild reduction of factor VIII:vWF Type 2 –molecular defect of VIII:vWF Type 3 – nearly no detectable level of factor VIII:vWF
and therefore factor VIII:C.
Clinical menifestation
Asymptomatic . Mucous membrane bleeding. Epistaxis Cutaneus bleeding. Gingival bleeding Menorrhagia
investigation
Full Blood Count – platelet normal APTT PROLONGE or normal Factor VIII LOW or normal. von Willerbrand Factor activity (ristocetin
cofactor) Ristocetin, an antibiotic that causes vWF to
bind to platelet taken from plasma. In healthy people, platelet rapidly agglutinate.
von Willerbrand Factor antigen Measure vWF protein and binding sites. Not accurate.
treatment
1-Mild-Moderate vWD : Desmopressin for minor surgery. Fresh frozen plasma. Cryoprecipitate.
2- in severe vWD : factor VIII concentrate for major surgery.
Prognosis & complications Lifelong tendency toward easy bruising, frequent
epistaxis, and menorrhagia. Carry medic-alert bracelet or chain & carry books
diagnosis, types etc.
Hepatic faliure
In addition to vit k dependent factors(II, VII, IX ,X) the liver synthesizes fibrinogen ,plasminogen,factors (V,VIII,XI,XIII).
Liver disease may be associated with increased bleeding tendency and this may be due to:
1-reduced vit K absorption.
2-reduced synthesis of coagulation factors.
3-increased fibrinolysis.
4-thrombocytopenia.
5-viral hepatitis or alcoholism .
6-DIC.
Management
In mild liver disease : vit K may be effective. In sever cases : tranxemic acid and fresh plasma may
control bleeding. REYE‘S SYNDROME : There is some evidence that use of aspirin in children up
to the age of
15 yrs ,may develop rarely liver damage(diffuse microvascular fatty infiltration)and acute encephalopathy with cerebral edema.
Vitamin k deficiency
Required for synthesis of Plasma factors II, VII, IX, and X
Causes of vit k deficiency: 1-poor dietary intake.
2-poor absorption.
3-failure of utilization.
4-lack of vit k synthesis ;prolong use of broad spectrum antibiotics.
General manifestation : 1-Bruising 2-GIT bleeding 3-hematouria 4-cerebral
bleeding
Management : Vit K 10 mg I.V.
ANTICOAGULANTS
Anticoagulants are drugs used for prevention and treatment of thrombosis e.g : DVT ,myocardial infarction ,renal dialysis and cerebral thrombosis.
Anticoagulant drugs includes :
1-oral anticoagulant.
2-heparin.
Oral anticoagulants ; cumarin “warfarin”
Action : Inhibition of the enzyme “vit K epoxide reductase”
Cumarin leads to the inhibition of synthesis of biologically active prothrombin factor II and factors VII,IX and X.
LABORATORY FINDINGS :
1-prolonged APTT
2-Prolonged PT (normal value is 11_15 sec)
Management :- In minor oral surgery the PT should be within the normal
therapeutic range (1.5-2.5 times the normal). INR should be checked on the day of operation or a day
before. The therapeutic range of INR is 2-3.5. The surgery should be a traumatic as possible. If any sign of bleeding from extraction socket ,use
oxidized cellelouse,with suture over the socket (eg. Figure 8 suture)and pressure pack is applied.
Heparin
Action: prevent fibrin formation through:
a. Inhibition of thrombin-fibrinogen reaction.
b. Inactivate factors 1Xa,Xa,X1a, and X11a.
c. Prevention of platelets aggregation (large dose).
Management :1.Surgery can be safely carried out ,when the effect
of heparin has ceased.
2.In renal dialysis, surgery is better carried out the next day.
Disorder characterized by coagulation pathway activation leading to diffuse fibrin deposition in the microvasculature and consumption of coagulation factors and platelets. Occurs as secondary complication of variety diseases. Caused by the systemic activation of coagulation pathways, leading to formation of thrombi throughout the microcirculation and widespread thromboses. There is consumption of platelets and coagulation factors and secondarily activation of fibrinolysis. As consequence, there is depletion of the elements required for hemostasis (consumptive coagulopathy) May be acute or chronic.
Disseminated Intravascular Coagulation (DIC)
Pathophysiology of DICMassive tissue
destruction
sepsisEndothelial
injury
Release of tissue factor Platelet
aggregation
Widespread microvascular
thrombosis Consumption of clotting factors and
platelets
Ischemic tissue damage
fibrinolysisVascular occlusion
Microangiopathic hemolytic
anemia
Activation of plasmin
Proteolysis of clotting
factor
Fibrin split products
Inhibition of thrombin, platelet aggregation and
fibrin polymerization
DIC
Precipitating factors:Including incompatible blood transfusion, severe sepsis,severe trauma or burns and cancer (metastatic cancer of the pancreas, lung, stomach or prostate).
The possible effect of DIC includes:a.Hemorrhagic tendencies.
b.Thrombotic phenomenon.
c.Hemolysis of red cells.
d.Shock.
Clinical features
Bleeding, thrombosis,bleeding far from common than thrombosis.
Subacute DIC :
Occures primarily in cancerous pts results in superficial +deep venous thrombosis.
Other manifestation :
High incidence of cardio respiratory faliure.
Treatment
Treat the disorder inducing the DIC first such as sepsis. Support the patient by correcting hypoxia, acidosis and poor
perfusion. Replace depleted blood clotting factors, platelets and
anticoagulant proteins by transfusion. Heparin may be used to treat significant arterial or venous
thrombotic disease unless sites of life-threatening bleeding coexist. Thus, the use of heparin remains controversial.
Treatment with anticoagulants or coagulants contained in fresh-frozen plasma usually needed in acute case.
Drotregocin alfa (recombinant activated protein C) reduces mortality in adults with DIC and sepsis.
Diagnosis of patient with bleeding disorders
An adequate history is the single most important part of the evaluation of Pts with abnormal bleeding tendency, clinical examination is also necessary, but the hematological tests are needed to confirm the diagnosis.
Diagnosis of patientswith bleeding disordersHistory 1.Bleeding problem in relatives.
2.Bleeding problem following trauma.
3. Bleeding problem following operation.
4. Medication that may cause bleeding problems.
5.Presence of disease that may have associated bleeding problems.
Diagnosis of patients with bleeding disorders Clinical Examination oThe skin and mucous membranes should be examined for :
petechia, ecchymosis, hematoma, angiomas and jaundice.oThe lymph nodes should be examined and mobility of the joint should be observed.
Diagnosis of patients with bleeding disorders Screeing Laboratory TESTS HemgramPTBTPTTTT
2) Screening testTest Mechanism
TestedNormal Value Disorder
Bleeding time (BT)
Hemostasis, capillary & platelet
function
3-7 min beyond neonate
Thrombocytopenia, von
Willebrand disease
Platelet count Platelet number 150 000 – 450 000 / mm^3
Thrombocytopenia
Prothrombin time (PT)
Extrinsic & common pathway
< 12 sec beyond neonate; 12-18
sec in term neonate
Defect in Vit K-dependent factor, liver disease, DIC
Activated partial
thromboplastin time (APTT)
Intrinsic & common pathway
25-40 sec beyond neonate;
70 sec in term neonate
Hemophilia, von Willebrand
disease, DIC
Source from : Nelson Essential of Pediatrics 5th edition
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