Presentation is a spectrum of severity
Immediate:  pain on<unk> , numbness, weakness
30 min-24 hours: decreased cap refill, pallor, skin mottling, cramping, paresthesias motor deficit
24- 48 hours: swelling, edema, contractures, signs of compartment syndrome
1-2 weeks:  clinical evidence of rhabdo, necrosis, gangrene, autoamputation
Assesses severity of symptoms
Skin color
Capillary refill
Distal sensation
Distal extremity temperature
Unintentional intra-arterial injection
Skin and soft tissue infections
Blunt cardiac injury
DVT
Hemorrhage of AV fistula
CT contrast media extravasation
Missile embolism
Allergic reaction