Evaluation of Safety of HEMOBLAST Bellows in Spine Surgery

Inclusion Criteria: * Subject is undergoing open, elective, spine surgery * Subject or an authorized legal representative is willing and able to give prior written informed consent for investigation participation * Subject is 22 years of age or older * Subject does not have an active or suspected infection at the surgical site * Subject in whom the Investigator is able to identify a Target Bleeding Site (TBS) for which any applicable conventional means for hemostasis are ineffective or impractical * Subject has a TBS with a Surface Bleeding Severity Scale (SBSS) score of 1, 2, or 3 Exclusion Criteria: * Subject is undergoing an emergency surgical procedure * Subject is undergoing a laparoscopic surgery * Subject is undergoing a cervical spine surgery * Subject is pregnant, planning on becoming pregnant during the follow-up period, or actively breast-feeding * Subject has a platelet count \< 100,000 per microliter or International Normalized Ratio \> 1.5 within 4 weeks of surgery * Subject receiving intravenous heparin within 12 hours before surgery or oral Coumadin within 2 days before surgery * Subject receiving antiplatelet medications within 5 days prior to surgery * Subject receiving aspirin within 7 days prior to surgery * Subject has an active or suspected infection at the surgical site * Subject has had or has planned to receive any organ transplantation * Subject has a known sensitivity or allergy to bovine and/or porcine substance(s) or any other component(s) of the hemostatic agent * Subject has a known sensitivity or allergy to Gadolinium * The subject has a contra-indication for MRI or gadolinium contrast agent according to clinical guidelines, local regulations or manufacturer's recommendations * Subject suffers from claustrophobia or fear of MRI, or has any contraindication to MRI (e.g., metal implants, spinal cord stimulator, etc. not suited to MRI) * Subject has American Society of Anesthesiologists classification of \> 4 * Subject has a life expectancy of less than 3 months * Subject has a documented severe congenital or acquired immunodeficiency * Subject has religious or other objections to porcine, bovine, or human components * Subject is currently participating or has participated in another clinical trial within the past 30 days and is receiving/has received an investigational drug, device, or biologic agent * Per investigator opinion subject is unable to fully cooperate with the study protocol. * The product will be placed in at the site where the dura is open * The product will be placed in the intradural or cranial space