The purpose of this expanded access study is to be able to provide treatment with HBOC-201 to patients with life-threatening anemia for whom blood is not an option.

HBOC-201 is not FDA approved for use in the United States, but is approved as an oxygen carrier in South Africa and Russia.

i. Initial Dose

For patients with a hemoglobin level less than 6 mg/dl, an initial dose of 32.5 g (one unit) of HBOC 201 is recommended, to be followed by infusion of additional units as necessary to achieve and maintain a total hemoglobin concentration above 6 g/dl, provided that the patient's circulatory volume is properly controlled and will not impose an inappropriate risk.

ii. Subsequent Doses

The need for additional dose administration should be assessed after each infusion as clinically indicated.

Dosing will be stopped if any one of the following occurs:

• resolution of critical ischemia
• death
• recovery of native Hemoglobin levels to > 6 g/dL,
• evidence of reticulocytosis

Inclusion Criteria:

1. Patients > = 18 years of age
2. Patients with hemoglobin < = 8g/dL with with active bleeding, physiologic evidence of critical ischemia, for example: elevated troponins, altered mental status, acute renal failure, lactic acidosis or central nervous system supply dependency
3. Patients or their Legally Authorized Representatives who are able and willing to provide informed consent

Exclusion Criteria:

1. Patients with known hypersensitivity or allergy to beef products
2. Patients with pre-existing uncontrolled hypertension, heart failure, renal failure, circulatory hypervolemia or systemic mastocytosis (on a case by case and quality of life determination)
3. Patients > 80 years of age (on a case by case and quality of life determination)
4. Patients who are eligible for blood transfusions