PE Diagnosis In Pregnancy

Question 1

What is the leading cause of maternal death in developed countries?

Answer 1

Pulmonary embolism (PE)

PE is a serious condition that poses significant risks during pregnancy.

Question 2

Why are pretest probability scores not applicable in diagnosing PE during pregnancy?

Answer 2

They have not been validated in pregnancy

This affects the reliability of these scores for pregnant patients.

Question 3

What happens to D-dimer levels as pregnancy advances?

Answer 3

D-dimer levels increase

This is due to ongoing haemostatic processes during pregnancy.

Question 4

What is the recommended first-line investigation for suspected PE in pregnancy?

Answer 4

Compression ultrasonography (USS)

This is used to confirm deep vein thrombosis (DVT).

Question 5

What should be done if USS confirms DVT and the patient is stable?

Answer 5

Further lung imaging may not add value

Lung imaging can expose both the fetus and mother to radiation.

Question 6

What imaging is required if USS is negative?

Answer 6

Further lung imaging

This is necessary to rule out PE.

Question 7

What are the two imaging options for further lung imaging in suspected PE?

Answer 7

CTPA or V/Q scan

The choice depends on several factors including gestational age and patient history.

Question 8

Which imaging method delivers a higher dose of radiation to the fetus?

Answer 8

V/Q scan

This is an important consideration in imaging selection.

Question 9

What is the risk of childhood cancer development associated with a V/Q scan compared to CTPA?

Answer 9

1 in 280,000 for V/Q scan vs < 1 in one million for CTPA

This highlights the comparative risks of the two imaging modalities.

Question 10

How can the radiation dose from a V/Q scan be reduced?

Answer 10

By using a perfusion scan alone initially

The ventilation scan should only be performed if the perfusion scan is positive.

Question 11

Which imaging method delivers a higher radiation dose to the mother?

Answer 11

CTPA

This is a critical factor when considering maternal safety.

Question 12

What is the increased risk of developing breast cancer from a CTPA compared to a V/Q scan?

Answer 12

13% higher risk

This statistic underscores the importance of careful imaging selection.

Question 13

Fill in the blank: A negative D-dimer may not be helpful to rule out the diagnosis of PE _______.

Answer 13

irrespective of the stage of pregnancy

This emphasizes the complexity of diagnosing PE during pregnancy.

Question 14

What treatment is reasonable for patients suspected of having PE during pregnancy?

Answer 14

Low molecular weight heparin (LMWH)

LMWH = doesn’t cross placenta
Warfarin = contraindicated: crosses placenta and is teratogenic and causes foetal ICH