A prospective pilot study examining nutritional supplements among vascular surgery patients with Critical Limb Ischemia (CLI). CLI patients have a high rate of malnutrition and has the potential to benefit greatly from nutritional intervention. The investigators plan to evaluate nutrition and functional status of patients by assessing objective lab values and the use of the hand grip strength test. Providing perioperative nutritional supplements to patients has potentially improved their nutritional status, which in turn may improve the patient's clinical status after surgery.