An 84-year-old male with a background of atrial fibrillation, type 2 diabetes mellitus and hypertension presents with acute right leg pain that started 3 hours ago. He has never experienced such pain before and is frightened that he cannot feel his leg. He is a lifelong smoker and drinks 40 units of alcohol per week. He has never had an operation before and takes aspirin, metformin and anti-hypertensives.