Case of the Month #45 Major Obstetric Haemorrhage - Part 2
How do POC coagulation results translate to clinical practice?
Actions based on TEG results-
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CK – Prolonged R time suggests a deficiency in clotting factors. If R time > 9 minutes, give 15ml/kg of FFP or 2 pools of cryoprecipitate.
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CFF - Reduced MA suggests fibrinogen deficiency. If CFF MA < 16mm give 3g of fibrinogen concentrate.
(An MA of 16mm correlates with fibrinogen concentration of 2g/L, an MA of 22mm correlates with fibrinogen concentration of 3 g/L). -
CRT (and CK) – Reduced MA (in the presence of a normal CFF MA) suggests a platelet deficiency. If CRT MA < 52mm give 1 unit of platelets. If CK MA < 50mm give 1 unit of platelets.
Actions based on ROTEM results -
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FIBTEM A5 < 11 mm (or fibrinogen < 2 g/L) - give fibrinogen concentrate (A5 7-11 mm give 4 g, A5 < 7 give 6 g).
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EXTEM CT > 75 sec (or prolonged APTT/ PT) - give FFP (booking weight < 50 kg give 3 units, booking weight > 50 kg given 4 units)
Notes on coagulation and clotting products
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Coagulopathy during MOH may be dilutional, consumptive, or due to DIC.
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Haemorrhage secondary to amniotic fluid embolus, uterine rupture or placental abruption may be associated with early onset DIC. FFP/ fibrinogen concentrate should be considered early for these conditions.
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FFP contains all clotting factors whereas cryoprecipitate contains high levels of factor VIII, fibrinogen and von Willebrand factor.
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Pregnancy is a prothrombotic state with higher baseline fibrinogen levels of 4-6 g/L (2-4 g/L in non-pregnant patients). This acts as a physiological buffer for haemorrhage.
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Fibrinogen levels decrease more rapidly during haemorrhage than other coagulation factors (often a predictor of progression to MOH).
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Fibrinogen <3 g/L, particularly < 2g/L is associated with poor outcomes.
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Fibrinogen < 2gL occurs in 1-2/1000 deliveries.
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Fibrinogen > 2 g/L is adequate for haemostasis during obstetric bleeding.
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Fibrinogen concentrate or cryoprecipitate can be used as the source of fibrinogen, depending on availability.
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There is evidence suggesting fibrinogen replacement using Fibrinogen Concentrate can reduce the need for FFP and cryoprecipitate.
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FFP and cryoprecipitate need to be thawed in the transfusion laboratory prior to use. This can take up to 40 minutes, therefore close and pre-emptive communication with the lab is essential.
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Cryoprecipitate- one pool contains 5 single units. 1-2 pools are recommended for an average adult.
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FFP- dose is 12-15 ml/kg, on average 4 units for an adult. Should be administered based on POC/ lab haemostatic tests, or after 4 units of RBCs have been administered if haemostatic tests are unavailable.
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1 Adult Dose (AD) of platelets should be administered in the first instance if platelet count < 75 x 109/L and/ or bleeding in ongoing. Platelets may need to be obtained from the local NHS blood and transplant (NHSBT) site which can take > 1 hour for delivery by blue light from ordering.