Acute Caremiddle twist
A 71-year-old man presents with two hours of severe left loin pain radiating into the groin, with vomiting. He has never had pain like this before. He smokes 20 cigarettes a day and takes perindopril; his blood pressure at his last general practice visit was 158/90 mmHg. He is pale and sweaty. Pulse 104/min, blood pressure 104/66 mmHg, temperature 36.6 degrees Celsius. The abdomen is soft, with tenderness in the left flank and no guarding. Urinalysis shows a trace of blood and no nitrites. Which one of the following investigations is most likely to explain his low blood pressure?