PE in Pregnancy
- Does PE risk change over course of pregnancy?
-nothing conclusive, but most studies show incidence of VTE roughly equally distributed across trimesters
-regardless, several large studies suggest risk of VTE is SIGNIFICANTLY HIGHER POSTPARTUM than antepartum
- Normal d-dimer in pregnancy?
-Limited utility in pregnancy b/c elevations are found in uncomplicated pregnancy, increasing w/ gestational age, peaking at early postpartum period
-Reference normal D-dimer levels (microgram/mL)
1st trimester: 0.05-0.95
2nd trimester: 0.32-1.29
3rd trimester: 0.13-1.7
- Can PERC be applied to pregnant women?
-Jeff Kline postulates that maybe one could use the PERC rule in pregnancy and adjust the HR (to 105) and D-dimer upward but this seems to be more conjecture than studied and validated
-Presumably you can’t use the PERC rule in pregnant women because they aren’t low risk patients; they were excluded from the initial derivation of the rule and thus the rule shouldn’t reasonably be applied to them
V/Q or CTPA to diagnose PE?-Controversial…partial dose V/Q scan actually has similar radiation to CTPA-Per Jeff Kline, because utility of V/Q is diminished w/ abnormal CXR, consider V/Q in pregnant patient w/ normal CXR and CTPA in pregnant patient w/ abnormal CXR-Caveat: First trimester- consider CTPA as retained urine in bladder will focus radiation onto fetus
**Special thanks to Rebecca Brafman and Dr. Shearer for inspiring this pearl : )
Schwartz, DR et al. DVT and PE in pregnancy: Epidemiology, pathogenesis and diagnosis. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2013.
Cunningham, FG. Normal reference ranges for laboratory valutes in pregnancy. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2013.
Kline, Jeff, auth. “PE in Pregnancy with Jeff Kline.” ERcast. Jeff Kline, 24 04 2013. web. 30 Aug 2013. <http://blog.ercast.org/2013/04/pulmonary-embolism-in-pregnancy/>.