This study will evaluate the performance of the Quantra System comprised of the Quantra Hemostasis Analyzer with the Quantra Surgical Cartridge in patients undergoing major surgical procedures specifically, major cardiac and vascular procedures and major orthopedic surgery (primarily complex spine surgeries).

The Quantra System is a fully integrated and automated in vitro diagnostic device which uses SEER Sonorheometry, an ultrasound-based technology, to characterize the viscoelastic properties of a whole blood sample during coagulation. The Quantra Surgical Cartridge was developed to monitor hemostasis during major surgical procedures in adult patients. The cartridge consists of four independent channels each containing different sets of reagents, which provide four measurements performed in parallel yielding six parameters that depict the functional status of a patient's coagulation system.

This multi-center, prospective, observational study will evaluate the performance of the Quantra System as compared to standard coagulation tests and comparable measures determined using the ROTEM Delta.

Inclusion Criteria:

• Subject is ≥18 years
• Subject is scheduled for either 1) cardiac or vascular surgery utilizing cardiopulmonary bypass (CPB) or 2) orthopedic surgery including major deformity correction spine surgery
• Subject has a cardiac assist device and is hospitalized for any procedure
• Subject underwent cardiac, vascular or orthopedic surgery and presents with acute bleeding or suspected hypercoagulability in a post-surgical unit
• Subject is undergoing emergency cardiac, vascular or orthopedic surgery
• Subject is willing to participate and he/she has signed a consent form

Exclusion Criteria:

• Subject is unable to provide written informed consent
• Subject is younger than 18 years
• Subject is incarcerated at the time of the study
• Subject is pregnant
• Subject is currently enrolled in a study that might confound the result of the proposed study
• Subject is affected by a condition that, in the opinion of the surgical team, may pose additional risks

The study population includes subjects 18 years or older undergoing a surgical procedure with high risk of intra- or post-operative bleeding. It is anticipated that approximately two-thirds of the enrolled subjects will be cardiac or vascular surgery patients and one-third will be orthopedic surgery patients.