HAEMATOLOGY MODULE:

COAGULATION DISORDERS 1

Adult Medical-Surgical Nursing

Blood Coagulation (Clotting) Factors

Platelets (thrombocytes)

Prothrombin

Other clotting factors: VIII and IX

Fibrinogen

(Vitamin K and Calcium required)

Anticoagulants

Plasminogen → plasminFactor CHeparin

These maintain balance by opposing the clotting factors:

Prevent unnecessary clottingEnable dissolution of clots

Blood Coagulation

Injury occurs Stimulates vasoconstriction to reduce blood

flow to the areaPlatelets adhere forming an initial plugThromboplastin released:Converts prothrombin → thrombinThrombin converts fibrinogen → fibrin (mesh)Plasminogen to plasmin (control)

Thrombosis: Description

Inappropriate blood clotting which usually leads to:

Obstruction of blood vessels impeding blood flow

ArterialVenous

Factors Increasing Risk of Thrombosis:

SmokingOral contraceptives / HRT (Oestrogen)ImmobilityInjury to blood vesselsPoor circulation related to:

Heart failureVaricose veins

Factors Reducing Risk of

Thrombosis:

Aspirin

Anticoagulant medication

Red wine

Anti-embolic stockings

Complete Blood Count (CBC) including platelet count

Prothrombin time/ PT International Normalised Ratio (INR) Partial prothrombin time/ PTT Activated PPTFibrinogen, Fibrinogen Degradation Products

(FDP), D - DimersBone Marrow Biopsy

Coagulation Disorders: Diagnostic Tests

Fluids available to aid coagulation

Fresh frozen plasma (FFP)PlateletsCryoprecipitate including: Fibrinogen, Factor VIII, Factor IX

Whole bloodPacked red cellsGamma globulin Anti-D

Coagulation Disorders: Classification

Thrombocythaemia

(In lecture 2):

Thrombocytopenia Haemophilia (Factor VIII; IX) Von Willebrand Disorder Acquired Coagulation Disorder

Thrombocythaemia

Thrombocythaemia: Description

Increased platelet production: >600,000 cmm3 (ref. 150 - 450,000)

Primary: no known causeMyeloprolific (bone marrow) disorder

Secondary: Usually reaction to a malignant or

inflammatory disorder/ splenectomy

Thrombocythaemia: Pathophysiology

Increased platelet count

Platelet dysfunction

Clinical Manifestations

Increased platelet count:Vaso-occlusion of capillaries (thrombi) leads

to: Visual disturbanceNumbness and burning in extremities

Platelet dysfunction:Haemorrhages: Gastro-intestinal, gums,

epistaxis, petechiae, purpura

Thrombocythaemia: Diagnosis

Patient history

Clinical picture

CBC (>600,000 mm3)

Bone marrow biopsy

Management and Nursing Care

Low dose aspirin reduces the risk of thrombi

Chemotherapy: &-interferon and hydroxyurea to controlPlatelet phoresis

↓ smokingAvoid NSAIDs/ alcoholAnti-embolism stockings