Bleeding, leukaemia and Denitstry Flashcards
What is the process of haemostasis?
Injury and tissue damage Vascular response - VASOCONSTRICTION Platelet adhesion and aggregation -VWF/PLATELET/FIBRI Unstable platelet clot Coagulation factor cascade Fibrin - STABILITY TO THE CLOT Stable clot
Describe the intrinsic pathway?
Via factors 12, 11, 9 and 8 to get to factor 10 (activated partial thromboplastin time (APTT))
Describe the extrinsic pathway?
Via factor 7 to get to factor 5 (prothrombin time (PT))
What do the intrinsic and extrinsic pathway lead to?
Prothrombin - thrombin - fibrinogen to fibrin
What are the 2 types of coagulation defect?
GENETIC - haemophilia A, B, C, VWD
ACQUIRED - liver disease, kidney disease, anti platelet, anticoagulation - heparin, warfarin, enoxaparin, dabigatran, rivaroxiban, antiplatelet, liver disease, Vit K deficiency, blood transfusion
What is haemophilia A?
Genetic coagulation defect
Deficient in factor VIII
Can be mild, moderate or severe
Spontaneous bleeding which doesn’t stop.
A loose platelet plug will form but blood oozes around
Dental extractions and surgery are dangerous
How do we treat haemophilia A?
Give factor VIII and treat ASAP
What is haemophilia B?
Genetic coagulation defect
Deficient factor IX
How do we treat haemophilia B?
Give factor IX - can be given daily as factor IX has a long half life
What is haemophilia C?
Genetic coagulation defect
Deficient factor XI
Rapid fibrinolysis
How do we treat haemophilia C?
Give fresh frozen plasma (FFP), factor XI and transexamic acid (stops fibrin breakdown)
What is transexamic acid?
Transexamic acid is an antifibrinolytic drug so stops the break down of fibrin
What is von willebrands disease?
Deficiency of von willebrand factor (VWF) - required for platelet adhesion Type 1(mild), 2, 3 and pseudoVWD
How do we treat VWD?
Factor VII infusion for upper major procedures
DDAVP (desmopressin) and oral transexamic acid for minor procedures
Factor VIII supplements given if any chance of oral trauma (prior to procedure)
Regional blocks / injections in the floor of the mouth can cause haemhorrage and potential airway obstruction
Avoid intramuscular injections
Name 3 types of anticoagulants?
HEPARIN - usually given for immediate effects in acute thromboembolism
ENOXAPARIN - LMWH, Inhibits factor Xa
WARFARIN
Describe warfarin?
Warfarin impairs synthesis of Vit K dependant coagulation factors in the liver (2, 7, 9, 10)
Requires active and regular monitoring via INR value
Usually takes 2 - 4 days to become effective
What are the indications for warfarin?
SHORT TERM USE : prophylaxis to prevent DVT Established DVT PE MI CABG
LONG TERM USE:
Recurrent VTE
Rheumatic heart disease and atrial fibrillation
prosthetic value replacement
What is INR?
Prothrombin time - Dependant on weight, mass, diet
Must be check on day, prior to procedures
Normal = 1
4 = no extractions!
What interferes with warfarin?
Antiplatelet drugs
Antibiotics - affects INR
Miconazole oral gel
Aspirin and NSAIDs - increased bleeding, less platelet adhesion and increased gastric ulcers
Metronidazole - avoided
Erythromycin - unpredictable effects
Daktarin (antifungal) - fatal, affects INR
Name 4 antiplatelet medications?
Aspirin - thrombotic cardio or cerebrovascular disease
Clopidogrel -IHD
Ticlopidine - IHD
Dipyridamole - adjunct to oral anticoagulants with prosthetic heart valves
What is the action of aspirin, clopidogrel, and ticlopodine?
Inhibit platelet aggregation to the blood vessel walls
Lasts for the life of the platelets (7 - 10 days)
What is the action of dipyridamole?
Acts directly on the enzyme in platelets and vessel walls
Reversible
Name 2 non steroidal antiplatelet medications?
NSAIDs - not used clinically for antiplatelet function
Ibuprofen/ diclofenac - reversible effect once the drug is cleared, platelet function restored
What is the normal bleeding time?
2 - 10 minutes
What is the effect of antiplatelet agents?
Longer bleeding time
Name 5 coagulation defects?
Liver disease Hepatocellular failure Vitamin K deficiency Increased fibrinolysis Thrombocytopoenia (less platelets)
What is the treatment for autoimmune causes of coagulation defects?
steroids
splenoctomy
What is the treatment for leukaemia, aplastic anaemia causes of coagulation defects?
Platelet transfusion
What is leukaemia?
Neoplastic proliferation of white blood cells in the bone marrow
What is leukaemia due to?
Genetic Ionizing radiation chemicals virus Lymphoblastic and non lymphoblastic causes
Descirbe acute lymphoblastic leukaemia (ALL)?
peak incidence 2 - 4 yrs
B lymphocyte neoplasm
blasts > clasts so white cells decrease
Pale / anaemic / gingival swelling
Describe acute myeloid leukaemia (AML)?
Non lymphoblastic (myeloblastic)
Proliferation of myeloblasts in tissues
Most common in adults
swollen sore bleeding gums, no infection
Describe chronic lymphocytic leukaemia (CLL)?
Most common type of leukaemia Anaemic proliferation of lymphoytes Older patients M>F thrush, inflitration of gingival tissues Recurrs/ relapses Need chemo
What is chemotherapy?
Gets rid of malignant and non rapidly dividing cells
Cytotoxic agents also affect the bone marrow and reusult in :
leukopoenia, neutropoenia, thrombocytopoenia, anaemia
What is oral screening?
Intervention to eliminate any likely causes of dental sepsis
Needs to be timed during count recovery
High dose regimes need extra vigilance as opportunistic infections can prove fatal
What do patients experience during chemo?
Sever mucositis
oral ulceration
superimposed opportunistic infections
Name 5 aids to symptomatic treatment?
Corsodyl rinse Betnesol mouth rinse Difflam rinse Beclotide spray Bite guards
What is mucositis?
Breach in oral mucosa
Fibrous slough and ulcers
Affects QoL - eating and drinking
Can become peri oral
What is neutropoenic gingivitis?
No neutrophils
Ulcers with no neutrophil response, leads to septacaemia
Increased perio disease and tooth loss
What patients does neutroppoenic gingivitis occur?
Immunocompromised
Name 3 opportunisitc infections?
Systemic aspergillosis
Herpes Simplex
Herpes zoster
What is systemic aspergillosis?
An opportunistic infection
It invades and kills bone
Antifungals reduce the severity but need to remove bone
What is herpes simplex virus?
An opportunistic infection
Spread by saliva
Flu for 1 week, temperature, pan oral ulceration, coldsores
Brought on by UV, tiredness, low immune system
What is herpes zoster?
Chicken pox virus
HIV, older, low immune system
Unilateral (never crosses the midline)
What is recommended prior to cancer therapy?
supplementation with chlorhexidine
Stabilise carious teeth
Smooth any sharpness
Remove teeth with doubtful prognosis
What is recommended during cancer therapy?
Chlorhexidine continued Fluoride mouthwash Decrease mucositis alleviate symptoms of xerostaemia avoid dental treatment
What is recommended is the patient is neutropoenic at the time of treatment?
Likely to induce bacteraemia so give prophylactic antibiotic cover
When is platelet cover required for surgeical procedure?
When platelet count
When is it best to provide treatment for those on chemo?
Best to treat just before or just after chemo (check platelets and neutrophils)
When can dental infections be fatal?
When pt on high dose of chemo
So remove any teeth likely to be pulpally involved or advanced perio disease.
