Ver el código de «Pulmonary embolism in pregnancy»

==Background==
[[File:Computed tomograph of pulmonary vessels.jpg|thumb|Pulmonary emboli can be classified according to the level along the pulmonary arterial tree.]]
*Incidence of [[VTE]] in pregnancy and postpartum is 1.72 per 1000<ref>James AH, et al. Venous thromboembolism during pregnancy and the postpartum period: Incidence, risk factors, and mortality. 2006; 194(5):1311–1315.</ref>
*Risk significantly elevated in the 6 weeks postpartum
**Risk of [[DVT]] equal in 1st and 2nd trimesters, higher risk in 3rd trimester and 3 weeks postpartum <ref name="multiple"> Chan et al. Venous Thromboembolism and Antithrombotic Therapy in Pregnancy. SOGC Guidelines. 2014.</ref>
**[[PE]] most commonly occurs in postpartum. <ref name="multiple"> Chan et al. Venous Thromboembolism and Antithrombotic Therapy in Pregnancy. SOGC Guidelines. 2014.</ref>
**Common risk factors include: 
***Advanced maternal age
***C-Section
***Obesity
***Multiple gestations
***Thrombophilia
***Prior [[VTE]]
*Risk returns to baseline by 12 weeks postpartum<ref>Kamel H, et al. Risk of a thrombotic event after the 6-week postpartum period. N Engl J Med. 2014; 370:1307-1315.</ref>
*Consider MI in differential as risk can increase 3-6 times during the postpartum period

{{Venous thromboembolism types}}

{{PE types}}

==Clinical Features==
[[File:Deep vein thrombosis of the right leg.jpg|thumbnail|DVT of right leg]]
{{PE clinical presentation}}

==Differential Diagnosis==
{{Chest Pain DDX}}

==Evaluation==
[[File:Pulm embolism.jpg|thumb|[[ECG]] of a person with pulmonary embolism, showing sinus tachycardia of approximately 100 beats per minute, large S wave in Lead I, moderate Q wave in Lead III, inverted T wave in Lead III, and inverted T waves in leads V1 and V3.]]
[[File:SaddlePE.png|thumb|A large pulmonary embolism at the bifurcation of the pulmonary artery (saddle embolism).]]
===Clinical Decision Rules===
'''YEARS Algorithm''' <ref> van der Pol LM et al. Pregnancy-Adapted YEARS Algorithm for diagnosis of Suspected Pulmonary Embolism. NEJM 2019; 380(12): 1139-49 </ref>. [https://www.mdcalc.com/years-algorithm-pulmonary-embolism-pe MDCalc link].

''Appears to be possible viable clinical decision tool to rule out PE in pregnant patients''

Utilizes D-dimer and presence/absence of three YEARS criteria: (1) clinical signs of DVT, (2) hemoptysis, (3) PE as most likely diagnosis''

*Clinical signs of DVT? If yes, obtain LE US to rule out DVT:
**Positive US LE ➟ initiate anticoagulant treatment
**Negative US LE ➟ continue algorithm
*Zero YEARS criteria ('''no''' signs of DVT, '''no''' hemoptysis, PE is '''not''' most likely diagnosis):
**D-dimer <1,000 ng/mL FEU ➟ PE excluded	
**D-dimer ≥1,000 ng/mL FEU ➟ PE not excluded (YEARS algorithm recommends CTPA)	
*Presence of ≥1 YEARS criteria (signs of DVT, hemoptysis, and/or PE is most likely diagnosis):
**D-dimer <500 ng/mL FEU ➟ PE excluded	
**D-dimer ≥500 ng/mL FEU ➟ PE not excluded (YEARS algorithm recommends CTPA)

===If clinical features suggestive of [[PE]] and lower extremity swelling===
*Begin with bilateral lower extremity duplex scan
**if positive→treat empirically for PE
**if negative→CTA
***CTA and V/Q scans yield approximately 0.025 rad and 0.040 rad respectively to the fetus<ref>Astani SA, et al. Detection of pulmonary embolism during pregnancy: comparing radiation doses of CTPA and pulmonary scintigraphy. Nucl Med Commun. 2014; 35(7):704-711.</ref>
***>5 rads is considered teratogenic<ref>Bentur Y, Horlatsch N, and Koren G. Exposure to ionizing radiation during pregnancy: perception of teratogenic risk and outcome. Teratology. 1991; 43(2):109-112.</ref>
***However, 20-100 times more radiation is delivered to maternal breast tissue with CT, increasing the risk of breast cancer<ref>Greer IA. Pregnancy complicated by venous thrombosis. N Engl J Med 2015; 373:540-547</ref>
*Up to 17% of pregnant patients have isolated pelvic [[DVT]](not found with ultrasound)<ref>Chan WS, Spencer FA, Ginsberg JS. Anatomic distribution of deep vein thrombosis in pregnancy. CMAJ. 2010; 182(7):657- 660.</ref>

;CT (with shield) vs. V/Q is roughly equivalent radiation exposure to fetus, but CT confers increased radiation to maternal breast tissue

{{Guidelines PE Pregnancy}}

===[[D-Dimer]]===
*D-Dimer MAY BE used with following limits with '''very poor evidence'''<ref>Kovac M. The use of D-dimer with new cutoff can be useful in diagnosis of venous thromboembolism in pregnancy. Eur J Obstet Gynecol Reprod Biol. 2010 Jan;148(1):27-30</ref><ref>http://blog.ercast.org/2013/04/pulmonary-embolism-in-pregnancy/</ref><ref>D-Dimer Concentrations in Normal Pregnancy: New Diagnostic Thresholds Are Needed. Kline et all. Clinical Chemistry May 2005 vol. 51 no. 5 825-829 http://www.clinchem.org/content/51/5/825.long</ref>
**1st trimester: <750 ng/mL (+50% increase from normal lab threshold)
**2nd trimester: <1000 ng/mL (+100% from normal)
**3rd trimester: <1250 ng/mL (+150% from normal)
*[https://www.mdcalc.com/years-algorithm-pulmonary-embolism-pe YEARS Algorithm]
**3-month incidence of VTE of pregnant patients without CTPA was 0.43%<ref>Van Der Hull T et al. Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study. Lancet. 2017 Jul 15;390(10091):289-297.</ref>
**Pregnancy-adapted YEARS algorithm recommends initiation of anticoagulation in positive US compression of symptomatic leg should there be signs of DVT
**Pregnancy-adapted YEARS algorithm <ref> van der Pol LM et al. Pregnancy-Adapted YEARS Algorithm for diagnosis of Suspected Pulmonary Embolism. NEJM 2019; 380(12): 1139-49 </ref> “Pulmonary embolism was safely ruled out by the pregnancy-adapted YEARS diagnostic algorithm across all trimesters of pregnancy. CT pulmonary angiography was avoided in 32 to 65% of patients"
***efficiency of algorithm highest during first trimester and lowest during third

==Management==
*[[Heparin]] and [[Enoxaparin]] are safe (coumadin is not)
**[[Heparin]] 80 units/kg IV bolus followed by continuous infusion 18 units/kg/hr <ref name="multiple1"> Tintinalli's 7th edition</ref>
**[[Enoxaparin]] 1 milligram/kg (100 IU/kg) SC every 12 or 24 h <ref name="multiple1"> Tintinalli's 7th edition</ref>
*[[Perimortem cesarean delivery]] with cardiac arrest with no ROSC in 5 min
*Consider [[Thrombolytics for pulmonary embolism|thrombolysis]] in severely unstable post-partum pulmonary embolism<ref>Stone SE and Morris TA. Pulmonary embolism during and after pregnancy. (Crit Care Med 2005; 33[Suppl.]:S294 –S300.</ref> (see [[thrombolytics for pulmonary embolism]])

==Disposition==
*Admit

==See Also==
*[[Pulmonary Embolism]]

==References==
<references/>

[[Category:Pulmonary]]
[[Category:Cardiology]]
[[Category:OBGYN]]
[[Category:Vascular]]