Acute management VTE during pregnancy and puerperium GTG

Question 1

What % of suspected VTE have VTE confirmed?

Answer 1

2-6%

Question 2

What % of untreated DVT will develop into PE?

Answer 2

15-24%

Question 3

What % of PE is fatal in pregnancy? When is the death most likely to occur?

Answer 3

Fatal 15%
66% will occur within 30 mins of embolic event

Question 4

If high clinical suspicion of DVT and USS doppler negative, what should be done?

Answer 4

Re-perform USS on Day 3 and Day 7

(If low clinical suspicion, stop Tx dose Tinz)

Question 5

What % of ECGs are abnormal in PE?

Answer 5

41%

Question 6

What are the most common ECG findings in PE?

Answer 6

T wave inversion 21%
S1Q3T3 15%
RBBB 18%

Question 7

What does the S1Q3T3 finding look like?

Answer 7

Question 8

What 1st investigations would you consider when Ix PE?

Answer 8

ECG
CXR

If signs of DVT → Leg doppler. If +ve no other imaging required

Question 9

If CXR is abnormal which chest imaging is preferred?

Answer 9

CTPA>VQ scan if chest XR abnormal

Question 10

What is the risk with V/Q scanning to the foetus?

Answer 10

Slight increased risk childhood cancer

Risk 1 in 17,000 per mGy
V/Q 0.5mGy
CTPA 0.1 mGy

(1/280,000 vs 1/1,000,000 - according busy SpR)

Question 11

Risk to mother with CTPA?

Answer 11

High radiation to maternal breast tissue (up to 20mGy)
Increased risk 13.6% above background, background 0.1% → 0.136%

Consider VQ if young women or Fhc BC or previous CT chest

Question 12

What bloods should be performed before commencing LMWH?

Answer 12

FBC
Coagulation
U+E
LFT

Question 13

Does LMWH cross the placenta?

Answer 13

No
No increased risk severe PPH

Question 14

At what creatinine clearance does the dose of Tinz/enoxaprin and dalteparin need to be adjusted?

Answer 14

Tinz if CC <20
Enox/Dalte <30

Question 15

When should you consider Anti-Xa monitoring?

Answer 15

<50kg
>90kg
Renal impairment
Recurrent VTE

Question 16

If post-op obstetric patient recieving unfractioned heparin, how often should platelets be measured?

Answer 16

Every 2-3 days from day 4 - 14 until stopped

Question 17

If massive PE with CV compromise, what is the preferred initial management?

Answer 17

IV unfractioned heparin

Question 18

If massive PE with CV compromise, what investigations should occur within 1 hours?

Answer 18

Portable ECHO
CTPA

If PE confirmed → Thrombolysis

Question 19

How may massive PE present?

Answer 19

Shock
Refactory hyperaemia
Right ventricular dysfunction on ECHO

Question 20

How is IV unfractioned heperin commenced

Answer 20

1) Loading dose 80units/kg
2) Continous infusion 18unit/kg/hour
3) APTT 4-6 hours after loading dose or 6 hours after any dose change
4) APTT target 1.5-2.5

If been thrombolysed does not need loading dose

Question 21

How long should treatment of PE be continued?

Answer 21

Either 6 weeks PP or 3 months total Tx

Question 22

What should factor Xa level be?

Answer 22

0.5-1.2

Question 23

What can be given to reverse unfractionated heparin?

Answer 23

Protamine Sulphate

Question 24

If VTE at term or near delivery what should be considered?

Answer 24

Unfractioned heparin

Question 25

When should unfrationed heparin be stopped before IOL of regional?

Answer 25

If IV 6 hours
Subcut 12 hours

Question 26

When shouldLMWH be stopped before IOL of regional?

Answer 26

24 hours

Question 27

If patient on TX dose LMWH, how should this managed if ELCS?

Answer 27

Last dose 24 hours pre-op, prophylactic dose 4 hours after and treatment dose 8-12 hours later

Question 28

What should be considered at CS if patient on TX dose tins?

Answer 28

Consider wound drain (abdominal or rectus), skin incision with interrupted sutures

Question 29

Give examples of cases where high risk of haemorrhage but need heparin? What should be given?

Answer 29

Anticoagulation required but also
- APH
- Coagulopathy
- Progressive wound haematoma
- Suspected intrabaominal bleeding
- PPH

IV unfractioned heparin

Question 30

What anticoagulation can be considered in the postnatal period?

Answer 30

Heparin (LMWH/unfractioned)
Warfarin
DOAC - if NOT breast feeding

Question 31

If women would like to switch to warfarin postnatally, what is the earliest point this can occur?

Answer 31

Day 5
Daily INRs Aiming 2-3
Heparin can be stopped when >2 for 2 days

Question 32

What is post thrombotic syndrome?

Answer 32

Chronic pain, heaviness, swelling, eczema, chronic pigmentation, ulceration.

42% post DVT in preg

Question 33

How can risk of post thrombotic syndrome be reduced

Answer 33

Prolonged course of LMWH > 12 weeks and compression stocking for at least 2 years

Question 34

What follow up and testing should be provided for woman who had VTE in pregnancy?

Answer 34

FU in obstetric medicine or obs team clinic
Consider thrombophilia testing once anti-coagulation testing stopped
Discuss contraception
Look for post thrombotic syndrome

Question 35

Switching warfarin to heparin?

Answer 35

Stop Warfarin
Give 1st dose LMWH when INR <2

Question 36

LMWH to warfarin

Answer 36

Continue LMWH for at leat 5 dats until INR in range for 24 hours, stop LMWH immediately if INR greater than upper limit

Question 37

LMWH to DOAC

Answer 37

stop LMWH and start DOAC at time of next secuedualted LMWH

Question 38

DOAC to LMWH

Answer 38

Stop apixaban/rivaroxaban/edoxaban, start LMWH at the time of the next dose of DOAC would have been due

Dabigatran - wait 12 hours after last dose before switching to LMWH