2015 37b VTE Management Flashcards
What investigations are needed to diagnose acute DVT?
- Compression duplex US
- If -ve & low suspicion, stop Tx
- If -ve & high suspicion, stop Tx but repeat on days 3 & 7
What investigations are needed for diagnosis of acute PE?
- ECG & CXR
- If also S&S DVT, compression duplex US
- If no S&S DVT, V/Q or CTPA
- CTPA preferred if CXR abnormal
- If normal but clinical suspicion persists, continue Tx
How do risks of V/Q & CTPA compare?
V/Q: slightly increased risk childhood Ca
CTPA: risk of maternal breast Ca
Absolute risk of both is very small
What blood tests should be performed before undertaking anticoagulant therapy for VTE?
- Full blood count
- Coagulation screen
- Urea & electrolytes
- Liver function tests
- NOT D-dimer or thrombophilia screen
In VTE Tx, which pts should have peak anti-Xa activity measured?
- Weight <50kg or >90kg
- Renal impairment
- Recurrent VTE
If post-op obstetric pts are on UFH, when should platelets be monitored?
Every 2-3 days
From days 4-14
Or until heparin stopped
What treatments are considered for massive life-threatening PE?
- IV UFH
- Thrombolytic therapy
- Thoracotomy & surgical embolectomy
What additional therapies can be of benefit in VTE?
- Graduated elastic compression stockings to reduce oedema
- Temporary IVC filter for iliac vein VTE
How long should LMWH be continued in Tx of obstetric VTE?
Remainder of pregnancy & at least 6 weeks PN
At least 3 months total
How should anticoagulant Mx of VTE be managed peripartum?
- Consider IV UFH
- Stop LMWH 24 hours prior to planned delivery
- Delay RA until 24 hours after last dose
- Do not give for 4 hours after spinal & do not remove epidural catheter within 12 hours of injection
What special considerations are made at CS in anticoagulated patients?
Wound drains (abdominal & rectus sheath)
Interrupted sutures to allow drainage of any haematoma
What anticoagulant choices are available postnatally?
Choice of LMWH or oral
It warfarin, avoid until D5 or longer if high risk PPH, regular blood tests
Neither contraindicated in BF
Consider DOAC if not BF
What proportion of women with suspected PE are ultimately diagnosed as such?
2-6%
If DVT remains untreated, what proportion develop PE?
15-24%
a) What proportion of PE in pregnancy is fatal? & b) what proportion of these occur within 30 minutes?
a) 15%
b) 66%
What ECG findings are common in PE?
- T-wave inversion
- S1Q3T3 pattern
- Right bundle branch block
What CXR findings might be seen in PE?
- Atelectasis
- Effusion
- Focal opacities
- Regional oligaemia
- Pulmonary oedema
a) What is the risk of childhood cancer from radiation exposure? b) what is the fetal radiation exposure for CTPA, & c) V/Q?
a) 1 in 17,000 mGy
b) 0.1 mGy
c) 0.5 mGy
How much does CTPA increase the lifetime risk of breast cancer?
13.6%
What proportion of women who have a VTE in pregnancy have an underlying heritable or acquired thrombophilia?
Almost half
What is the dosing regime for treatment-dose enoxaparin?
<50kg 40mg BD or 60mg OD
50-69kg 60mg BD or 90mg OD
70-89kg 80mg BD or 120mg OD
90-109kg 100mg BD or 150mg OD
110-125kg 120mg BD or 180mg OD
>125kg Discuss with haematologist
What is the dosing regime for treatment-dose dalteparin?
<50kg 5000 units BD or 10000 OD
50-69kg 6000 units BD or 12000 OD
70-89kg 8000 units BD or 16000 OD
90-109kg 10000 units BD or 20000 OD
110-125kg 12000 u BD or 24000 OD
>125kg Discuss with haematologist
What is the dosing regime for treatment-dose tinzaparin?
175 units/kg/day
In unsuccessful resuscitation attempts, at what stage should a perimortem CS be performed?
5 minutes
