DVT in preg

Question 1

incidence of VTE in pregnancy/PP

Answer 1

50% in PP period, 1st week most common
50% in preg, most common 3rd trim

Question 2

pregnancy assc changes that make VTE more likely

Answer 2

1. hypercoag
2. inc venous stasis
3. Dec venous outflow –> vena cava compression

Question 3

where is DVT in preg most likely to happen?

Answer 3

proximal LLE –> iliac and iliofemoral vs

Question 4

risk of VTE in preg (4)

Answer 4

1. personal hx- 3-4x recurrence risk in pregnancy
2. thrombophilia- MC factor V (3-8% of ppl heterozygous)
3. cesarean deliv- 4x risk compared to SVD. extra if PPH or infection
4. comorbidities: obese, CV disease, sickle cell, HTN

Question 5

dosing for lovenox in pregnancy

Answer 5

LMWH
1. prophylactic- 40mg QD
2. intermediate dosing- 40mg BID
3. adjusted dose- 1mg/kg BID

Question 6

dosing for UFH in preg

Answer 6

1. prophylactic dose-
   a: 1st trim- 5-7.5k BID
   b: 2nd trim- 7.5-10k BID
   c: 3rd trim- 10k BID
2. adjusted dose- 10k or more BID
   adjust to target PTT (1.5-2.5k control) 6hrs after injection

Question 7

warfarin for VTE prophylaxis in pregnancy

Answer 7

vit K antagonist– only used when mechanical heart valve bc heparin does not work as well

TERATOGEN- wk 6-13 most risk, so use heparin at this time. for deliv, consider CD due to risk of infant bleeding

Question 8

DOACs and anti-Xa in pregnancy

Answer 8

NO DATA.
crosses placenta and leaks into BM

Question 9

what can you do if imaging negative for DVT but you have high clinical suspicion?

Answer 9

1. MRI
2. empiric AC
3. reimage in 3-7 days

Question 10

what test is more accurate for PE in pregnancy

Answer 10

CTA chest and VQ scan have the same accuracy

Question 11

do we need to check factor Xa lvl with LMWH?

Answer 11

NO.
small studies showed theoretical need for inc dose when using adjusted dose LMWH. BUT other studies should few women really needed inc dose.

Question 12

AC and delivery timing

Answer 12

LMWH- can convert to UFH in anticipation of deliv
1. prophylactic dose- dc 12hrs prior to IOL/CD
2. adjusted dose- dc 24hrs prior

UFH
1. if >7.5k units BID, dc 12hrs prior and check PTT

Question 13

what can you use to reverse UFH?

Answer 13

protamine sulfate

NOT indicated for prophylactic dosing

Question 14

how soon can UFH be restarted after delivery/epidural? LMWH?

Answer 14

UFH- 1hr
LMWH-
a. prophylactic- 12hr after epidural
b. intermediate/adjusted dose- 24h after epidural