Transcript Coagulation disorders in pregnancy

Coagulation disorders in pregnancy
Hematological Changes During Pregnancy:
1-Expansion of plasma volume and hemodilution.
2-Hb level increases, but there is physiological anemia.
3-RBC count decreases.
4- S. iron decreases, iron binding capacity increases.
5. Increase iron absorption from the gut.
6. Increase coagulation factors, so there is
hypercoagulable state, except factors XI, XIII, and
antithrombin III.
7. Decrease in fibrinolytic activity.
8. Decrease platelet count
Normal hemostasis:requires 3 main factors:
• Vascular constriction
• Platelet aggregation and formation of
platelet plug
• Fibrin formation.
Fibrin formation
Coagulation system during pregnancy:
Pregnancy represent a hypercoagulable state.
This include the following:
• Plasma fibrinogen concentration rises
during pregnancy by about 50%.
• Increase in factors V, VII, VIII, IX, X, XII.
Hemostatic problems associated with pregnancy:
• Thromboembolism.
• Hemorrhage with or without coagulopathy .
Basic definition
Venous thromboembolism (VTE ),any thrombo
embolic event in the venous system.
Deep venous thrombosis (DVD)
radiologically confirmed occlusion of the deep venous
system of the leg sufficient to produce symptoms of
pain or swelling.
Pulmonary embolism (PE)
radiologically confirmed occlusion of pulmonary
arteries sufficient to cause symptoms of
breathlessness,chest pain or both
Thromboembolism (TE) is the most common
cause of maternal death during pregnancy.
The most dangerous period for fatal
pulmonary thromboembolism (PE) is the 1st
week postpartum, then the 2nd week.
Most cases occurs after CS. Most maternal
deaths after CS are due to PE. 90% of death
occurs in the 1st 24 h after delivery.
Risk factors:
• 1- Hypercoagulable state of pregnancy.
• 2- Decrease activity of naturally occurring
anticoagulant.
• 3- Decrease fibrinolytic activity.
• 4- Increase tendency to venous stasis during
pregnancy.
5. Other factors pregnancy related:
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Operative delivery.
Age and parity.
Obesity over 76 kg
Restricted activity
Estrogen for suppression of lactation.
Endothelial injury
6. Other factors not pregnancy related:
• Previous TE.
• Lupus
anticoagulants,
anticardiolipin
antibodies, and antiphospholipid syndrome.
The thrombosis could be venous or arterial
and could occur at any site.
• Inherited thrombophilia.
• smoking
Clinical Features of Venous TE:
1- Superficial thrombophlebitis:
This means inflammation of a superficial vein
which if extended to a deep vein it carries a
risk of PE.
2. DVT:
The classical signs of DVT are leg edema, calf
tenderness, and positive Homans sign, which is
calf pain on dorsiflexion of the foot, it could
be asymptomatic.
3 -PE
a. Massive PE: cyanosis, shortness of breath,
chest pain, hemoptysis.
b. Small PE: transient dyspnea, tinge of cyanosis,
some pleuritic chest pain, unproductive cough,
unexplained pyrexia, tachycardia, leukocytosis.
Diagnosis of DVT:
• Clinical features usually affects left femoral
vein.
• Impedance plethysmography (IPG), little
value in 3rd trimester.
• Dopplar US, same as IPG.
• Duplex US, used in pregnancy.
• Contrast venography, gold standard.
• Iodine 125 fibrinogen scan
• D –dimer level
Diagnosis of PE:
...CXR
...ECG
...perfusion / ventilation lung scan
...arterial blood gas analysis.
...pulmonary angiography.
...CT scan
Management of venous TE during pregnancy:
• Acute phase treatment.
• Chronic phase treatment.
Acute phase treatment:
1. Thrombolytic therapy: by streptokinase, and
tissue plasminogen activaters. It can not be
recommended during pregnancy except as a
life saving procedure as in case of:
..... shocked patient with massive PE.
..... iliofemoral venous thrombosis
2.
Anticoagulants: unfractionated heparin
40,000 IU daily continuous intravenous
infusion.Monitoring of the drug by APTT.
If you want to stop the effect of heparin you
should stop the drug and give protamin
sulfate 1 mg for every 100 IU.
Heparin is given for 3-7 days.
3. Surgery.
Chronic phase treatment:
Warfarin which crosses the placenta. If this drug
is given during pregnancy it should be stopped
at 36 weeks. The action of warfarin is
monitored by prothrombin time (PT).
DIC (Disseminated intravascular coagulation):
trigger mechanism of DIC during pregnancy:
1- Endothelial injury:
• preeclampsia.
• Hypovolemia.
• septicemia
2. Release of thromboplastin as in:
• Abruptio placentae.
• Amniotic fluid embolism.
• Retained dead fetus.
• Intrauterine sepsis
• Hydatidiform mole
• Placenta accreta
3. Release of phospholipid as in:
• Intravascular hemolysis
• Incompatible blood transfusion
• Large fetomaternal bleed
• septicemia
Clinical manifestation of DIC:
1-Asymptomatic: compensated state. There is
lab evidence of increased production and
breakdown of coagulation factors, as in PET
and in retained dead fetus.
2. Variable degrees of thrombocytopenia
3. Massive uncontrollable hemorrhage.
Diagnostic tests:
1.Thrombin time:
2. Increase in APTT.
3. Increase in PT
4. Decrease in fibrinogen level
5. Decrease in platelet count.
Management:
• Fluid replacement to avoid renal shut down
usually by simple crystalloid eg Hartmanns
solution
• FFP which contains all coagulation factors
• Fresh blood transfusion
Thrombophilia and adverse pregnancy outcome
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Severe PET
Recurrent early pregnancy loss
IUGR
Late fetal loss
Venous TE during pregnancy