Haematology Flashcards
Coagulation cascade
Damage to vessel wall
- Exposure of collagen and tissue factor
- VWF in plasma binds collagen
- Platelets adhere to vWF & Collagen
Primary haemostasis
4. Platelets activate
release ADP Thromboxane
2ndary haemostasis
5. TF & platelets activate clotting factors - make thrombin
- Thrombin converts fibrinogen to fibrin clot
- stable clot formation
What periop measure can be taken to minimise non autologous RCCtfusion undergoing elective surgery
Starting Hb - aim high
Men >130g/l
Women >120
Consider Iron replacement (PO v Infusion)
Functional iron deficiency
Acute v chronic
What periop measure can be taken to minimise non autologous RCCtfusion undergoing elective surgery
Starting Hb - aim high
Men >130g/l
Women >120
Consider Iron replacement (PO v Infusion)
Ferrous Sulfate
- better taken once every other day (Blood 2017)
Routine preop setting
small amounts - time / compliance
Acute v chronic
Functional Iron Deficiency
Functional iron deficiency
- Anaemic chronic disease =
upreg hepcidin - reduce ability to absorb
Normal ferritin (can be iron deficient)
PO Iron trial
If fail PO iron
Iron Studies
IV Iron
- should see improvement in week
Minimise bleeding
?drugs stopped
antiplatelet agents / anticoagulants
dont forget to restart
Surgical techniques
Consider TXA
(EBL >500)
Giving earlier better -
Intraoperative cell savage
Guideline
Appropriate transfusion triggers
TRICC (transfusion in critical care
1999
7-9 conservative
(unless significant sy / cardiac hx)
vs
10-12 liberal sttegy
no difference in mortality / morbidity
Jehovah witness
- Advanced directive
elective setting
relevant paperwork - documentation of willing to accept
(RCC PLT FFP - most wont accept)
others ‘matters for conscience’
some will accept
Discussion with them
- Pre-Op optimisation of Hb
- Consider cell salvage
- Clear communication
Jehovah witness
- Advanced directive
elective setting
relevant paperwork - documentation of willing to accept
(RCC PLT FFP - most wont accept)
others ‘matters for conscience’
some will accept (PCC and not FFP)
PCC - vit k clotting factors
Cryoprecipitate vs Fibrinogen
Discussion with them
Key members - anaesthetist + surgeon + Liaison + Patient
- Pre-Op optimisation of Hb
Aim >130
Fe infusion liberal
EPO (need b12 folate ferritin)
- Consider cell salvage
Explain in continuous circuit - Clear communication
Document what’s been said & agreed
PeriOp blood conservation
Cell salvage
1 Reduce RCC transfusion
- Ideally have 24h access
training approp - Collecting only mode
surgery only blood loss >500 - Not contraindicated
malignancy / infection
discuss with patient
Leucodepletion filter - Current evidence not support routine C section use
Major Haemorrhage
Bleeding in excess 150ml/min
Loss more than 1 blood volume in 24h
50% total blood volume <3h
Bleeding =
SBP <90mmg
HR >110
Coagulopathy with massive Haemorrhage
Loss coag factors & platelets
Dilution
Consumption from activation
Colloids affects on haemostasis
Hypothermia
Acidosis
Anaemia (rheology)
Protein C activation (endog anticoag inactivating Va VIIIa
Hyperfibrinolysis (release t-PA)
Loss of FIBRINOGEN mass / function
first important consequence of Major Haemorrhage
Massive haemorrhage
TXA early
APTT /PT >1.5
Fibrinogen <1g = established coagulopathy
Keep Fib >1g is too low
TRAUMA est 1:1:1 initially
blast trauma - fit men - battlefield
Hypothermia
Acidosis
Hypocalcaemia (CaÍ >1)
Hyperkalaemia
