Ischemia-reperfusion injury remains a difficult problem facing vascular surgeons because of its associated high morbidity and mortality. The basis for tissue injury during ischemia depends on depletion of tissue oxygen and energy substrates. Cell injury, as documented cellular edema and lysosomal degranulation, begins after only 30 min of ischemia. Irreversible cellular changes occur after 4-6 h of skeletal muscle ischemia. Following acute arterial occlusion, the restoration of blood flow heralds the onset of biochemical events, forming the basis of what is known as the reperfusion syndrome. This tissue injury is maximal in areas with the greatest blood flow during reperfusion. Endothelium-leukocyte interactions play an important role in ischemia-reperfusion injury. Both endothelial and white blood cells have the biochemical machinery and capacity to generate molecular signals, to express adhesion proteins, and to produce toxic metabolic by-products. Since the microcirculatory changes in ischemia-reperfusion injury parallel those seen in inflammation, the leukocyte-endothelial interaction can explain many of the reactions associated with the early phases of ischemia-reperfusion injury.
Sixty-nine limbs with infrapopliteal arterial injuries were evaluated in 68 patients. Thirty-five (50%) cases were complicated by acute limb-threatening ischemia. Management consisted of revascularization (26 limbs), ligation (15 limbs), fasciotomy only (2 limbs), observation (18 limbs), and primary amputation (8 limbs). Penetrating injuries (n = 35) had a 33% incidence of ischemia and a reduced frequency of associated injury. One delayed amputation (3%) was required. In contrast, blunt injuries (n = 34) had a 68% incidence of ischemia and a greater frequency of associated injury. There were 20 amputations in the blunt group, including eight primary amputations performed in limbs with profound ischemia, complex open fractures, severe soft-tissue damage, and neural injury. Observation or ligation of single arterial injuries resulted in no early amputations. Associated local injuries in both groups included fracture or ligamentous disruption (64%), severe soft-tissue damage (32%), and nerve dysfunction (36%). In both groups, 15 of 35 ischemic limbs were salvaged by prompt revascularization (11 penetrating and four blunt injuries). Aggressive revascularization with autogenous repair or bypass is recommended for management of penetrating trauma. Though a good outcome will be achieved in some patients with combined blunt trauma and infrapopliteal arterial injury, the probability of delayed amputation and prolonged disability must be consciously integrated into the decision to pursue limb salvage. The prognosis for blunt injury complicated by arterial ischemia is poor; thus the severity of associated local and remote injuries will affect the results of revascularization program.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.