QuestionSBA
QuestionChoice
V/Q scan is a viable scan to diagnose PE but is preferred if the patient has renal impairment, a contrast allergy or is pregnant.
10005295
e
V/Q scan
QuestionChoice
The most likely diagnosis here is a pulmonary embolism from an underlying deep vein thrombosis (DVT). CT pulmonary angiogram (CTPA) is the diagnostic test of choice for a PE and will show a filling defect in the pulmonary vasculature.
10005291
a
CT pulmonary angiogram
QuestionChoice
Lower limb Duplex can be helpful if a DVT is thought to be the cause of the PE as in this case but does not provide a definitive diagnosis for the cause of the oxygen desaturation and tachycardia which needs treating more urgently. Therefore, CTPA remains the next best investigation.
10005294
d
Doppler USS left leg
QuestionChoice
Chest x-rays are typically normal in PE and therefore not the next best investigation. However, possible findings include Fleischner sign (an enlarged pulmonary artery), Hampton's hump (a peripheral wedge-shaped opacity), and Westermark's sign (regional oligaemia). The chest x-ray can be helpful in ruling out differentials (e.g. pneumonia, pneumothorax) too.
10005292
b
Chest x-ray
QuestionChoice
D-dimer is a highly non-specific test but has a 95% negative predictive value i.e. it is useful in ruling out a PE if negative. The Well's score in this case is at least 9.5 and only if the Well's score is 4 or less, a D-dimer should be measured.
10005293
c
D-dimer
Concept
Chapter
2693
3724
Pulmonary Embolism
Topic
132
Respiratory
13605
A 59-year-old male is seen in the Acute Medical Unit. He complains of sudden onset pleuritic chest pain and three episodes of coughing up blood. On examination, he has a unilateral swollen, red and tender left calf. His oxygen saturations are slightly low at 95% on air and he is tachycardic with a pulse rate of 105. He is known to have a background of bowel malignancy for which he is awaiting surgery.

Which of the following is the next best investigation?
a