Safety/Feasibility Study of HBOC-201 in Amputation at/Below Knee From Critical Lower Limb Ischemia

Inclusion Criteria: * Subjects ≥ 18 ≤ 75 years of age * Scheduled amputation at or above ankle joint, or a more proximal location but below or through the knee joint * Documented severe lower extremity peripheral artery occlusive disease confirmed by clinical symptoms of critical limb ischemia and: * Frankly gangrenous tissue that merits amputation or * Angiographic evidence of occlusive peripheral artery disease within one month of screening * Participant or legal representative signs informed consent * Willingness to follow study instructions and follow-up visits Exclusion Criteria: * No informed consent is obtained * If medically inappropriate to administer 250 mL colloidal solution daily for 4 consecutive days * Uncontrolled hypertension (BP \> 160/90 mm Hg) despite 2 antihypertensive meds or BP \> 180/100 mm Hg if untreated * Severe liver dysfunction defined by Total Bilirubin \> 3 mg/dL or twice the normal limit of serum AST or ALT * Symptomatic CVD diagnosed w/ in last 6 months or known high grade carotid stenosis * Any severe or unstable medical condition that might interfere w/ the evaluation of study medication * Cardiogenic shock (cardiac index \< 2 L/min/m2, PCWP \> 18 mm Hg) * Amputation above knee joint or below ankle joint * Any amputation whereby primary skin closure not technically feasible * Candidate for percutaneous or surgical revascularization * Cardiac failure defined by a NY class III/IV or left ventricular ejection fraction \< 30% * Life expectancy \< 60 days * Systemic mastocytosis * Previously demonstrated beef product allergy * Myocardial infarction w/ in 30 days * Participation in another trial w/ in last 30 days * Woman who is pregnant or breastfeeding * Amputation with known infection at site of skin closure * Renal dysfunction requiring dialysis, or serum creatinine level 2.5 mg/dL * Peripheral vascular occlusion from cardio arterial emboli * Uncontrolled diabetes blood glucose ≥ 400 mg/dL