Thromboembolic disorders Flashcards
What is Haemostasis?
s is the body’s normal physiological response for the prevention and stopping of bleeding/haemorrhage
Name the three mechanisms that are activated in the process of haemostasis?
Constriction of blood vessels – vasoconstriction (to reduce blood flow)
Aggregation of platelets – formation of a plug
Blood clotting – coagulation of the blood
What is the coagulation phase?
When damage to a blood vessel is so extensive that the platelet plug fails to stop bleeding the blood clotting mechanism commences
What is the Extrinsic Pathway?
Chemicals released by damaged cells
outside circulation –FAST response
What is the intrinsic Pathway?
inner vessels damaged within the circulation- SLOWER response
What is the common Pathway?
Prothrombinase
Prothrombin
Thrombin
Fibrinogen
Fibrin clot
Name the changes in the haemostatic system during pregnancy
Cardiac output increased by approx 40%
Blood plasma increased by 50%
Rise in RBC in last two trimesters
Normal pregnancy a state of hypercoagulability - protective mechanism against blood loss at delivery
(Hypercoagulability is increased in the early puerperium and then slowly returns to pre-pregnant state over a few weeks)
Increase in fibrinogen, prothrombin and factors V11, V111, 1X and X
What is Fibrinonlysis?
Process which destroys the clot
Factors in the blood activate plasminogen which activates plasmin which digests fibrin threads…fragments then removed by phagocytosis and macrophage
What is Disseminated Intravascular Coagulation?
Disseminated Intravascular Coagulation (DIC) also known as consumptive coagulopathy, is an acquired disorder of haemostasis, which often heralds the onset of multi-organ failure
What is the incidence for Disseminated Intravascular Coagulation?
with reference
Rare less than 1:1000 pregnancies
Robson & Waugh (2013 p 262)
What is the 10 steps of pathophysiology- coagulation failure in pregnancy
- Endothelial damage > Release of thromboplastins from damaged cells into maternal circulation (intrinsic pathway)
- Extrinsic pathway triggered by activating a coagulation cascade. E.g. Bleeding from placental site or perineal wound.
- If tissue damage so severe then clotting occurs at the site of the epithelial damage and throughout the vascular system (micro thrombi)
- This process uses large quantities of clotting factors (V and VIII), platelets and fibrinogen
- Some small blood vessels can be occluded by micro thrombi which can lead to organ failure
- The damaged tissue within the organs also initiates more clotting which makes the situation worse
- Eventually all the clotting factors are used up and bleeding occurs
- Ironic situation that bleeding cannot be stopped as there is a clotting deficiency despite widespread clotting
- Petechiae develop, bleeding from GI tract, nose, GU tract can be observed
- If untreated death from haemorrhage
What is petechiae?
point flat round red spots under the skin surface caused by intradermal haemorrhage (bleeding into the skin)
list the causes in obstetrics of DIC
Major placenta abruption
Major haemorrhage
Pre-eclampsia / eclampsia
Intra-uterine death, missed abortion or trophoblastic disease
Amniotic fluid embolism
Ruptured uterus
Sepsis
HELLP syndrome
list other triggers that can cause DIC, with referance
Hydatidiform mole
Acute Fatty Liver of pregnancy
Breast, uterine, ovarian cancer / and metastases
Other infections - viral haemolytic B Strep, E Coli
Mismatched blood transfusion
Other haemoglobinopathies
Immune disorders – snake bite
Burns
Robson & Waugh (2013, p262)
list the complications of DIC
Renal failure and anuria
Liver failure and jaundice
Dyspnoea and cyanosis
Convulsions /coma /brain damage
Retinal damage – reduced sight /blindness
Pituitary – Sheehans Syndrome (necrosis of pituitary gland)
Death due to hypovolaemia
provide a list of pre-conception issues and care when a woman has DIC
Pre-conception issues and care
History of DIC in previous pregnancy – recurrence risk dependent on cause
F/U and debriefing
Medical conditions such as Von Willebrand’s disease or Thrombocytopenia/Thrombophillia
Women with chronic DIC may be at high risk of pregnancy complications
Needs discussion
What is considered as Major and Severe PPH?
Major PPH is more than 1000ml blood loss and severe PPH is blood loss greater than 2000mls
How can you manage a severe haemorrhage?
Major PPH is more than 1000ml blood loss and severe PPH is blood loss greater than 2000mls
Anticipate – risk factors – preventative measures – remove causes
Active management of primary PPH
A 14 gauge grey venflon should already be sited in addition to IVI access
Take blood for FBC group, clotting and G & S
If HB less than 9g/dl inform duty registrar and cross match 2 units blood
Active management of the third stage of labour using an oxytocic drug and CCT (reduces PPH risk, NICE 2017)
CALL for MEDICAL HELP – 2222Inform consultant obstetrician & anaesthetist
Inform haematology consultant
Appoint a scribe to record even
What should be done during resuscitation for DIC?
IV access 2 x 16 gauge cannulae
Oxygen 10-15 L by mask with reservoir
Elevate legs
Take blood for:FBC, cross match, clotting screen (fibrinogen, APPT) U & Es AND monitoring
Insert indwelling catheter with measuring chamber (30-60 mls per hr)
Monitor fluid intake and output
Monitor pulse, BP, Resps, Temp and Oxygen saturation
Consider CV
List the different types of fluid replacements
Crystalloid : e.g. Hartmann’s
Colloid: e.g. Gelofusin until blood available
Blood
Fresh frozen plasma
Cryoprecipitate
Platelet concentrate
Packed cell
Name the steps used to identify and treat the cause of DIC
Remove the trigger
Empty the uterus, bimanual compression of the uterus
Repair any tears/episiotomy
Improve uterine tone
Administer uterotonic medication:Oxytocic e.g. syntometrine/ergometrine
Syntocinon 40 IU in 500 mls N/S 125 mls/h
Carboprost (Haemabate) 250 mcg IM
Misoprostol 800 mcg PR
What can be done medically and surgically to treat DIC?
Examination under anaesthetic if stable.
Improve tone as mentioned
Uterine compression with B-Lynch suture
Arterial ligation
Hysterectomy – rare if women has severe DIC and already collapsed and compromised
Radial arterial embolisation to control bleeding
Management in HDU
Are there anymore ways of managing DIC?
Repeat and check coagulation screen
Evacuation of uterus if RPC
Close liaison with haematologist and blood bank
All blood loss measured and clearly documented
Postnatal observations – HDU 1-1 care
Attention/observations of all wound and cannulation sites for signs of bleeding
Assist mother when well to NNU/SCBU
Obstetric postnatal review – debrief – counselling for future pregnancies – risk factors
Name three inherited haematological diseases
- Von Willebrands Disease (coagulation factor disorder)
- Factor V leiden disease (thrombophilia)
- Haemophilia (disease of males but pregnant women may be a carrier)
What is Von Willibrand’s disease?
a familial inherited haematological bleeding disorder in pregnancy which is characterised by either a defect or deficiency of the clotting factor V111.
Usually identified in young adults – menorrhagia, bleeding after dental extraction, bruising, nose bleed
There are 5 types of Von Willibrand’s disease
True of false?
False
there are only three
- 75% women quantitative deficiency of VWF (least severe)
- 20% women qualitative deficiency
- 5% women –severe almost complete deficiency of VWF
What type of screening tests could u do for the Von Willibrand disease?
FBC
Serum ferritin (iron levels)
Clotting screen PT (normal) activated partial thromboplastin time prolonged
Bleeding time – usually prolonged, normal in mild cases
Platelet aggregation test – measures platelet efficiency
Von Willebrand factor antigen and factor V11
How can VWF be managed?
Early identification and screening
Observe levels of VWF and factor V111 in mild cases normalise in third trimester
First trimester risk of bleeding – consider risk factors – APH
Regular monitoring of platelet count and bleeding time
Blood taken for group and save x match 2 units
Alert for APH and PPH in labour
Epidural contraindicated in type 3
Prompt removal of cannula following delivery to reduce risk of bleeding
Active management of third stage and complete place
How would you manage VWF?
Postpartum - fall in VWF and V111 in first 24 hrs – 22% risk of primary PPH
25% risk of secondary risk of PPH > 5 weeks postpartum
Vigilant postnatal observations (MEOWS)
Daily check of neonate for bleeding – cord stump
Avoid neonatal circumcision – check with haematologist
Care with heel prick for Guthrie test – local pressure for 5 mins.
Check for bruising / intracranial bleeding/cephalhaematoa
Neonatal blood screening
What is Hemophilia?
Hemophillia, also known as factor V111 is a genetic disorder, caused by missing or defective V111 which is a clottting protein.
What is Thrombophilia?
A disorder of the haemostatic system which results in an increased risk of thrombosis (increased blood clotting)
Factor V Leiden (FVL), Inherited or Acquired?
Inherited
Prothrombin 20210, Inhertited or Acquired?
Inherited
Antiphospholipid syndrome is inherited, true or false?
False it is Acquired
Protein C deficiency, Inherited or Acquired?
Inherited
Protein S deficiency, Inherited or Acquired?
Inherited
Antithrombin deficiency, Inherited or Acquired?
Inherited
Sophie suffers from antiphospholipid syndrome, which is a type of thrombopilia, what are considered as complications that Sophie may experience?
Venous Thromoembolism
Placental Abruption
Pre-eclampsia
Poor fetal growth
Sophie suffers from antiphospholipid syndrome, which is a type of thrombopilia, what methods of management to help Sophie
Assessment of risk (VTE score)
Consultant led care - Management with multi-disciplinary team including haematologist
Known condition – anticoagulation Warfarin , non-pregnant, LMWH in pregnancy.
Women taught self-injection technique
TED stockings
Management and care as for PE and DVT
What is VTE?
VTE is Venous Thromboebolism, this is a condition that includeds DVT or PE and it invloves blood clotting, in particular areas of the body.
How many maternal deaths during 2013-2015 were caused by VTE with ref?
26 Maternal Deaths
MBRRACE,2017
In maternity PE, is a type of exercise True or false?
False Its pulmonary Embolism YOU CHICKEN
Within the MMBRACE how many maternal deaths occured during 2009-2013 from VTE?
64 Maternal deaths
Within the MMBRACE how many maternal deaths occured during pregnancy from VTE?
48 deaths
Within the MMBRACE how many maternal deaths occured antenatally from VTE?
50% of deaths
Within the MMBRACE how many maternal deaths occured postnatal from VTE?
50% postnatal deaths delivered by CS section
Within the MMBRACE how many maternal deaths occured with no risk factors from VTE?
17% deaths
Within the MMBRACE how many maternal deaths occured from VTE? Where the women were obese?
53% were obese
List the 9 types of people, that are at higher risk of VTE?
- Thrombophilia
- Previous VTE
- Obesity
- Smoking
- Surgery
- Immobility
- Dehydration
- (pregnancy increases risk of a VTE 10 fold and up to 25 fold in the puerperium (Robson & Waugh, 2013)
What is DVT?
DVT, Deep Vein Thrombosis
DVT is a blood clot in one of the deep veins in the leg (usually in the left leg in pregnant women)
Why are pregnant women more susceptible to developing DVT?
- Reduction of blood flow
- Hypercoagulability
- Abnormalities/damage to the vessel
what do the RCOG Green-top Guidelines 37a (2015) suggests in regards to the assessment of VTE?
•All women should have Risk assessment for venous thrombosis (VTE) undertaken at booking and repeated at any hospital admission, intrapartum or immediately postpartum and before discharge from hospital
What should be given to women who have an increased risk of VTE?
May require prophylactic LMWH (e.g. fragmin, clexane), TED stockings in AN period, and/or PN period
Name the symptoms of DVT?
PAIN
Unilateral swelling (occasionally bilateral)
Redness or discolouration
Difficulty weight bearing on the affected leg
Low grade pyrexia
Occasionally lower abdo pain
How would you diagnose DVT?
- If a DVT is suspected through observation then urgent referral needed
- Doppler ultrasound recommended
- D-dimer testing not recommended by RCOG ( D-dimers are breakdown products of fibrin found in the blood)
How can DVT be treated?
- IV heparin regime should be commenced as soon as possible
- Pain relief
- MEOWS
- Compression (TED) stockings
- Avoid dehydration
- LMWH regime (warfarin is not recommended in pregnancy)- dosage dependent on weight
- Avoid air travel
What is PE?
Pulmonary Embolism .A PE is a clot that has formed in the pulmonary circulation, usually from a clot that was a DVT and has travelled through the circulatory system
What is the symptoms of PE?
Chest Pain
Shortness of breath
Cough with blood
How is PE diagnosed and treated?
- If DVT already diagnosed then presumptive diagnosis can be made with symptoms
- If not diagnosis by CXR or VQ scan
Treatment:-
- Urgent referral
- IV heparin
- Then LMWH thromboprophylaxis
- See local Trust policy
What intrapartum care would u give to an VTE?
- If an A/N VTE then women will be taught to self inject LMWH as outpatient once stabilised
- Before labour starts LMWH must be stopped
- If spontaneous labour women should stop administration as soon as possible
- If elective IOL, LMWH should be stopped 24 hours before
- Epidural/spinal anaesthetic to be discussed with senior anaesthetist and Should not be administered within 24 hours of last dose of LMWH
- MEOWS and close monitoring
- After delivery recommence LMWH (BD)
What puerperium care would u give to an VTE?
- Thromboprophylaxis should continue for at least 6 weeks postnatal until at least 3 months of anticoagulant therapy has been given
- Can be offered LMWH or warfarin(If commence warfarin will need INR tests)
- TEDs should continue to be worn on the affected leg for up to 2 years after the event
- Prescriptions for the entire postnatal course of LMWH should be issued in secondary care.
- This will help ensure that women receive the full course without the need to visit their GP to obtain another prescription.
- This also provides a double safety net since the prescription will be checked by a hospital pharmacist, who ensures the correct weight-appropriate dose is dispensed
