This is a pragmatic, prospective, multi-center, randomized, active-control, single-blinded, non-inferiority phase 3 trial in adult cardiac surgical patients. Up to 12 Canadian hospitals will participate, and the trial will require up to 2 years for patient recruitment.

Twelve-hundred bleeding adult cardiac surgical patients who require fibrinogen supplementation due to acquired hypofibrinogenemia after CPB will be included. Patients will be randomized to receive equivalent doses of either fibrinogen concentrate (Octafibrin) or cryoprecipitate when the blood bank receives the first order for fibrinogen supplementation and deems it to be in accordance with accepted clinical standards. Thereafter, patients will be treated according to their assigned group each time fibrinogen supplementation is ordered during the treatment period (24 hours after termination of CPB). No other aspects of care will be modified.

The primary efficacy outcome will be the number of Allogeneic blood products (ABP) (red blood cells [RBCs], pooled or apheresis platelets, and plasma) administered during the first 24 hours after termination of CPB. Safety outcomes will be measured for the first 28 days after surgery, which is the duration of participation of each patient in the trial. Comparisons will be by intention-to-treat (ITT) (primary) and per-protocol (PP) analysis. One interim analysis will be conducted after 600 patients have been treated to determine whether the study should be terminated for safety reasons, demonstrated non-inferiority or futility reasons.

Inclusion Criteria:

1. Patients undergoing index cardiac surgery with CPB in whom fibrinogen supplementation is ordered in accordance with accepted clinical standards (significant hemorrhage and known or presumed hypofibrinogenemia).

Exclusion Criteria:

1. Receipt of fibrinogen rich products (fibrinogen concentrate or cryoprecipitate) within 24 hours before surgery 2. History of severe allergic reaction to cryoprecipitate or fibrinogen concentrate 3. Refusal of ABPs, fibrinogen concentrate or cryoprecipitate due to religious or other reasons 4. Fibrinogen level known to be >3.0 g/L within 30 minutes of IMP order (to eliminate the risk of raising patients' fibrinogen levels to >4.0 g/L with supplementation 5. Known pregnancy