What are the risks of an above the knee amputation if severe hypertension and diabetes?

Slow wound. Healing but chances are if you need to have an above knee amputation then you're at greater risk of getting a blood infection and dying if you don't get the amputation.
What r risks without. Any significant surgery in a dm with severe HTN is risky; those diseases r considered major risk factors. If the need or benefit od doing surgery outweighs risk of not, need surgery. The important means of preventing complications include careful thorough medical clearance, insuring control of any medical problems; proper and competent anesthesiology; an competent surgeon, then good rehab.