Vascular Trauma and Inflammatory/Vasculitic Disease
Trauma
Hard signs - pulsatile bleeding, expanding hematoma, absent distal pulse, thrill or bruit, or ischemia with neurologic deficit - mandate immediate exploration or on-table angiography. Soft signs warrant an ankle-brachial index: above 0.9 with no soft signs permits observation, while 0.9 or less or any abnormal finding calls for CT angiography. Knee dislocation is a classic trap, because the tethered popliteal artery tears even when pulses remain palpable - measure the index and image liberally. Repair with autologous vein, use shunts in damage-control settings, and keep a low threshold for fasciotomy.
Inflammatory and vasculitic disease
Takayasu arteritis affects young women, often of Asian descent, with arm claudication, absent pulses, and arch branch stenosis; operate only during remission. Giant cell arteritis in a patient over 50 with headache, jaw claudication, and visual loss is an emergency: give steroids immediately and never wait for temporal artery biopsy, because vision loss is permanent. Buerger disease in young smokers requires absolute cessation. Polyarteritis nodosa and Behçet disease involve medium vessels, and operating on active inflammation invites anastomotic failure.
Traps
A normal ESR or CRP does not exclude vasculitis. A pulseless young woman does not have atherosclerosis. A warm, pulseless limb after trauma is an intimal injury until proven otherwise - spasm is never a diagnosis.
Rule of thumb: in vascular trauma an index below 0.9 earns an angiogram; in suspected giant cell arteritis, steroids come before biopsy.