haematology Flashcards
What is haemophilia?
Haem A- factor VIII deficiency
Haem B- factor XI deficiency
X linked recessive
Affects secondary haemostasis
Associated w nose bleeds, bleeding gums, prolonged bleeding from wounds, joint bleeding
What are signs and symptoms?
Nosebleeds
Easy bruising
Spontaneous gingival bleeding
GI bleeding
Difficult clotting after cuts
Bleeding into joints
Cranial bleeds
What is the tx for haemophilia?
Antifibrinolytic agents (transexamic acid)
DDAVP (desmopressin)
Direct factor replacement
Emicizumab
Novosen/FEIBA
Mild- no tx unless surgery/trauma, or on demand tx for epistaxis, menorrhagia etc
Moderate- prophylaxis, tx at S/T
Severe- regular prophylaxis, tx at S/T
What is tranexamic acid?
Antifibrinolytic agent
Blocks binding of plasminogen and plasmin to fibrin
Mouthwash/tablets
Use QDS, 5-10 mins post x
Rinse w 5ml of 5% solution, hold for 2 mins then spit
5 days
What is desmopressin?
Synthetic replacement of vasopressin (reduces urine)
Stimulates release of FVIII and VWF from stores in pts w mild Haem A and VWD
What are signs and symptoms of VWD?
VWF promotes platelet aggregation and is a carrier for factor VIII
What is the tx for VWD?
Desmopressin
Direct factor replacement
How would you manage an exam in a haem pt?
No BPE
Manage soft tissues carefully
Place IO films carefully
Thorough med history
How do you manage a bleed?
1. Pts know how to manage
2. Local measures, apply pressure
3. Contact haem centre and ask advice
What are drugs that can affect bleeding?
Cytotoxic drugs (eg hydrochloroquine, infliximab)
NSAID (eg ibuprofen, naproxen)
SSRI anti depressants (eg citalopram)
Immunosuppressants (eg methotrexate)
Drugs affecting nervous system (eg gabapentin, carbamazepine)
What is low molecular weight heparin?
Delivered subcutaneous- anticoagulant
VTE, post valve replacement, cancer, spinal injury
Short onset of action, short half life
Renally excreted
Last tx 24hrs prior procedure, post tx 4 hrs
No interruption in prophylactic tx
Eg. Enoxaparin (Clexane)
What are antiplatelet drugs?
Impairs primary haemostasis
Reduce platelet aggregation 
Increases bleeding time, dual increases even more
Prevents arterial thrombosis
Often used in combination after cardiac stents
Eg. Clopidogrel, aspirin, ticagrelor
Don’t need to be stopping before primary care- may lead to prolonged bleeding however
What is warfarin anticoagulant?
Vit K antagonist
For DVT, AF, stroke, valve replacement
Multiple interactions
Inhibits factor II, VII, IX, X and protein C and S
Metabolised by liver- cytochrome P450
Slow on and off action
What is International Normalised
Ratio?
Time taken for clot to form in blood sample relative to standard of 1
Stable INR hx- 72 hrs prior procedure
Unstable within 24hrs of procedure
>4- refer to med practitioner for advice, don’t stop med yourself
Warfarin interacts w many antibiotics and anti fungal which increase bleeding risk (erythromycin, fluconazole, metronidazole)
What are DOACs?
Dabigatran- direct thrombin inhibitor- prevents fibrinogen turning into fibrin
Rivaroxaban and apixaban- inhibit factor Xa
Fast onset, fixed doses, less interactions, lower risk of major bleeds, increased risk of GI bleeding, no antidote
When do you do tx for a pt on DOACs?
If pt started meds or had PE/DVT within 3 months- discuss w haematologist before omitting
Tx 12 hrs post BD dose or 18-24hrs post OD dose
Restart- 6hrs post w no bleeding present
What are general principles?
Prevent dental disease
Thorough med history taking
Careful liaison w MDPT
Plan appt times
Defer care if necessary
Careful technique
Clear written post op instructions
Local measures
What are local measures?
Horizontal mattress suture
Haemostatic packing material eg. oxidised cellulose
Warm wet absorbent gauze
Tranexamic acid
What is IV anticoagulant?
Unfractionated heparin
Continuous infusion
Monitor w APTT- ratio 1.8-2.8 aim
What are anticoagulant INR targets?
INR 2.0-3.0
-Tx of DVT/PE (3-6 months)
-atrial fibrillation (lifelong)
INR 3.0-4.5
-recurrent DVT/PE on warfarin (life long)
-mechanical heart valve (life long)
What are side effects of warfarin?
Bleeding
Skin necrosis
Embryopathy if in first trimester
What is the reversal of warfarin?
Stop warfarin (2-3 days)
Vit K (IV, SC, O)
Clotting factor concentrate eg. beriplex
What is acute leukaemia?
Proliferation of primitive precursor cells in bone marrow
W/o differentiation
Anaemia, neutropenia, thrombocytopenia, bone pain
What is acute lymphoblastic leukaemia?
Malignant proliferation of lymphoblasts in bone marrow
Main kids
Poor prognosis in adults
Tx= intensive chemo, allogenic bone marrow transplant, CAR-T cell therapy
What is acute myeloid leukaemia?
Malignant proliferation of myeloblasts in bone marrow
Most adults
Gum infiltration in acute monocytic subtype
Tx= intensive chemo, allogenic bone marrow transplant, palliative chemo, supportive care w blood transfusions
What is chronic lymphocytic leukaemia?
Proliferation of mature lymphocytes usually B cells
Can be incidentally diagnosed
Can present w anaemia, infections, lymphadenopathy, splenomegaly, night sweats
Lymphocytosis on blood film
Good prognosis
What is chronic myeloid leukaemia?
Gradual onset
Can be diagnosed incidentally
High WBC count and splenomegaly
Philadelphia chromosome
BCR-ABL tyrosine kinase
3 phases
Tx= tyrosine kinase inhibitor eg imatinib, allogenic stem cell transplant rare
What is myelodysplasia?
Abnormal production of cells in bone marrow
Disease of elderly
Can be asymptomatic
May present w anaemia, thrombocytopenia, pancytopenia
Several subtypes
Can transform to AML
Tx= supportive care, low dose chemo
In young- intensive chemo and bone marrow transplant
What is Hodgkin lymphoma?
Painless lymphadenopathy
Sweats, weight loss, fever
4 subtypes
Reed-Sternberg cell diagnosis on biopsy
Tx= chemo, radiotherapy, autologous/allogenic stem cell transplant
What is non Hodgkin lymphoma?
Low grade
-gradual onset, asymptomatic, incurable
Tx= chemo, radiotherapy, transplantation
High grade
-rapidly progressive
-symptomatic
-curable
Tx= chemo, radiotherapy, transplantation
What are myeloproliferative disorders?
Polycythaemia Rubra Vera (PRV)
RBC
Chronic myeloid leukaemia (CML)
WBC
Essential thrombocytopenia (ET)
platelet
Myelofibrosis
marrow stroma
What are symptoms of myeloma?
Lytic lesions in bone
Hypercalcaemia
Hyper viscosity
Renal failure
Anaemia
Infections
What is the diagnosis and tx of myeloma?
Blood and urine tests
X-rays and CT/MRI
Bone marrow
Tx= chemo, radiation, stem cell transplant
What are some oral manifestations of haem disease?
Infection in immunocompromised
Bleeding disorders
Lymphoma eg tonsillar
Gum hypertrophy eg AML
Macroglossia (amyloid deposition)
Angular stomatitis and glossitis (Fe/B12 deficiency)
Cyanosis
Hereditary haemorrhagic telangiectasia
Maxillary hypertrophy (extramedullary haemopoiesis)
What is packed red cells blood transfusion?
Centrifugation removes majority of plasma
~200-300ml per unit
In severe anaemia/major haemorrhage
1 unit raises Hb by 10g/L
Need to be ABO an Rh matched
What is a platelet transfusion?
Pooled from 4 or 1 donor/s
~200-300ml per dose
In platelet function disordered pts who are bleeding/need surgery
Prophylaxis reversible BM failure
What is a fresh frozen plasma blood transfusion?
Plasma separated and frozen to <-25C to maintain coag factors
Thaw before use
<1L dose
Prophylaxis
Major haemorrhage
Plasma exchange
NOT fro warfarin reversal
What is a cryoprecipitate blood transfusion?
Slowly thaw FFP to precipitate FVIII, VWF, fibronectin and fibrinogen
Thaw before use
~500ml per dose
For low fibrinogen eg DIC
What are alternatives to transfusion?
B12/folate/iron replacement
Tranexamic acid
Erythropoietin
Vit K
Intra operative cell salvage
Predeposit autologous blood donation
What are risks of transfusion?
Vol of fluid infused- circulatory overload
Allergic reaction
Haemolytic transfusion reaction
Alloimmunisation
Infection (acute/delayed)
Electrolyte abnormalities
Hypothermia
Psychological
Iron overload (repeated transfusion)
What is the tx of VWD?
Type 1- desmopressin, sometimes VWF concentrate
Type 2- desmopressin OR FVIII/VWF concentrate
Type 3- FVIII and VWF concentrate
Tranexamic acid for all types
What is the tx for platelet function disorders?
Tranexamic acid
DDAVP
Platelet transfusions
Novoseven
