Trauma Induced Coagulopathy

Dr. Abdul Gafoor. M.TMD (Anesthesiology)

ICU - ALKHOR HOSPITAL

Impact of TIC

Incidence:25-35 % of Trauma cases. Mortality:3-4 fold higher in TI

24 hour mortality - 8 times higher(Brohi K et al Current Opin Crit Care 13:680-685:2007)

Higher transfusion requirements. Longer intensive care unit and hospital stays. More days requiring mechanical ventilation. Greater incidence of multiorgan dysfunction.

Coagulation cascade

Feed back for hemostasis & Hyperfibrinolysis

Mechanism in Trauma

Review of Mechanism

Acute Coagulopathy of Trauma Shock (ACoTS)

Syn:ETIC(Early Trauma Induced Coagulopathy) Starts in the prehospital period. Shock&Hypoperfusion is the cause. Dilution,Hypothermia,Loss of coagulation

factors not significant at this stage. Thrombomodulin-ProteinC pathway is activated

in hypoperfusion. Hypercoagulable state and risk of thrombosis

due to Protein C depletion.

Risk factors

significant risk factors for life-threatening coagulopathy injury severity score > 25 systolic BP < 70mmHg acidosis with pH < 7.10 hypothermia with BT < 34℃

lethal triad hypothermia, metabolic acidosis,

progressive coagulopathy (Ferrara A etal Am J surg1990:160:515)

Acidosis

Marker of inadequate tissue oxygen utilization

Duration of hypotension and acidosis related to abnormal coagulation

Treated by improving tissue oxygen delivery

Brohi K etal Ann of surg 2007;245:812-818

Dilution of clotting factors

Resuscitation fluid Transfused PRBC

are plasma poor Factor

replacement (FFP etc)often given late

Coagulation affected when factors are below 25%

Hypothermia Strong relationship between temperature

and survival.Less than 32°C-100% mortality

Mild Hypothermia-platelet function reduced Severe Hypothermia-Function of clotting

factors reduced PT,PTT performed routinely at 37°C do not

reflect the real state and misleading

Effect of hypoperfusion and coagulopathy on mortality

Brohi K etal Ann of surg 2007;245:812-818

Changes in fibrinogen synthesis and breakdown in pigs after haemorrhage, hypothermia, and acidosis.

Fries D , Martini W Z Br. J. Anaesth. 2010;105:116-121

© The Author [2010]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournal.org

Role of Fibrinogen

Loss and consumption of clotting factors

Clotting factors lost proportionate to duration of shock

Loss not a problem until IV fluids are administered

Massive tissue factor exposure in prehospital phase gives intense thrombosis

Thrombosis and fibrinolysis leads to consumptive coagulopathy

Clot formation and quality impaired

The Lethal sixpack

Tissue Injury Shock Dilution Hypothermia Acidosis Inflammation

Sequence of clotting factors affected in bleeding

Fibrinogen F1 Prothrombin F2 Factor F5 Factor F7 Platelets

Hippala ST Anesth Analg 1995

Increased bleeding tendency if fibrinogen level is below1.5-2g/dl

Critical Fibrinogen level may be reached before need for RBC

Updated European guidelines

Target Hb of 7-9 g/dl. (Grade 1C). Ionised calcium levels be monitored during

massive transfusion. (Grade 1C) .If low CaCl2 FFP in a dose of 10-15ml/Kg(Grade 1B) Platelets to maintain a platelet count above 50 ×

10 9/l. (Grade 1C). Above 100 × 10 9/l in multiple trauma or TBI (Grade 2C) .Initially4-8 platelet concentrates or one aphaeresis pack. (Grade 2C).

Crit Care 2010;14:R52

Updated European guidelines

Single haematocrit measurements not a good marker for bleeding. (Grade 1B).

Serum lactate and base deficit are sensitive tests to estimate and monitor the extent of bleeding and shock. (Grade 1B).

PT,aPTT,INR,Fibrinogen and platelets estimation recommended((Grade 1C)

Thromboelastometry recommended(Grade 2C) Maintain Normothermia

Crit Care 2010;14:R52

Updated European guidelines

If there is TEG signs of functional fibrinogen deficit

If Fibrinogen levels of 1.5-2gm/dl(level grade 1 C)

Initial dose of 3-4gms or 50mg/Kg

Repeated dose guided by TEG or lab assessment (grade 2 C)

Crit Care 2010;14:R52

Fibrinogen

Updated European guidelines

Antifibrinolytic agents be considered in the

bleeding trauma patient (Grade 2C). In established hyperfibrinolysis(Grade 1B)

Tranexamic acid 10-15 mg/kg followed by an infusion of 1-5 mg/kg per hour or

ε-aminocaproic acid 100-150 mg/kg followed by 15 mg/kg/h(guided by thromboelastometry)

Aprotinine not recommended Caution in renal failure

Crit Care 2010;14:R52

Antifibrinolytics

Updated European guidelines Novoseven(rFVIIa) if major bleeding in blunt trauma

persists despite standard attempts to control bleeding and best-practice use of blood components. (Grade 2C).

PCC for the emergency reversal of vitamin K-dependent oral anticoagulants. (Grade 1B).

Desmopressin (DDAVP) considered ONLY in refractory microvascular bleeding if the patient has been treated with platelet-inhibiting drugs such as aspirin. (Grade 2C).

Antithrombin concentrates not recommended. (Grade 1C).

Crit Care 2010;14:R52

Fibrinogen

Fibrinogen as low as 2gm found to reduce post operative blood loss upto 32%(Karlsson etal.Thromb.Hemost 2009)

ROTEM guided fibrinogen administration reduced transfusion rate and postoperative blood loss

Fibrinogen improved dilutional coagulopathy induced by HES by increasing clot firmness

Fibrinogen&PCC avoided PRBC transfusion in 29%patients when compared to FFP(3%)

Fibrinogen &PCC avoided platelet transfusion in 91%patients compared to FFP(56%).

Scochi etal crit care 2011;15R83

Prothrombin concentrate PCC

Initially used for immediate reversal of warfarin PCC available in different concentration of

ingredients in different commercial products. only factor 9 is standardised.

PCC contain prothrombin&factors 7,9,10 Prothrombin is the major thrombogenic agent in

PCC. Combination of PCC and Fibrinogen was found to

be most effective in liver injury.

Tranexamic acid

Blocks the lysine binding site of plasmine

CRASH 2 trial(Clinical Randomization of an Antifibrinolytic in Significant Hemorrhage) showed Tranexamic acid reduced blood transfusion in a dose of 20mg/Kg

EACA (epsilon aminocaproic acid) another alternative.

Fresh Frozen Plasma FFP:RBC close to 1:1 ratio beneficial in

massive transfusion.In nonmassive;1:2 optimum.

No RCTs,only retrospective data. 7 studies favoring high ratios(1:1) regarding

mortality reduction;2 studies against. Time for FFP thawing, a confounding factor. Severity of injury another confounding

factor(received more PRBC) Each unit of FFP independently associated with

2.1%higher risk of MOF and 2.5%higher risk of ARDS.

Recombinant Factor 7 rFVIIa (Novoseven)

Not a first line treatment In blunt trauma ,when standard therapy fails. In diffuse small vessel coagulopathic bleeding Hct>24,Platelets>50000,fibrinogen 1.5-2gm/L

and Acidosis,hypothrmia&hypocalcemia corrected First dose200mcg/Kg after 8 units PRBC Second and Third dose100mcg/Kg ,1 and 8

hours later.

Summary TIC starts early in trauma (ACoTS)in the pre-

hospital period and caused by shock, hypoperfusion & Inflammation

Aggravated by hypothermia,Acidosis,Dilution&loss of coagulation factors.

PT,PTT,INR,Hct unreliable in assessment. Thromboelastometry highly recommended Fibrinogen /cryoprecipitate highly recommended. Prothrombin concentrates(PCC) to be considered. Antifibrinolytics to be considered. Novoseven for specific indications.