A post-op elderly woman

A 70-year-old, obese woman, who was diagnosed of Cervical Ca, underwent a total hysterectomy with removal of both ovaries. The operation was successful.

On the day of discharge, she suddenly developed dyspnoea. The doctor found out that she was tachycardic, tachypneic and was in respiratory distress. There was no sign of deep vein thrombosis.

ECG was done immediately. ABG showed hypoxaemia.

1. What is the most likely diagnosis? What do you expect to see from ECG?

(Clue: Post-menopausal woman, obese, post-surgery, malignancy)

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