Allogeneic blood products transfusions are often necessary to treat perioperative bleeding in patients undergoing complex scoliosis surgeries. A prospective, randomized trial is designed to evaluate if the infusion of fibrinogen concentrate may reduce allogeneic blood transfusion in patients undergoing scoliosis surgery. Eligible patients will be randomly assigned to treatment group (fibrinogen concentrate infusion) and control group (normal saline infusion), and functional fibrinogen will be measured to guide the infusion of fibrinogen concentrate. Perioperative blood loss, intraoperative blood loss, and the amount of perioperative allogeneic blood transfusion will be compared between the two groups to determine the effect of fibrinogen concentrate infusion.

This is a prospective, randomized, double-blinded, placebo controlled trial to evaluate the effects of fibrinogen concentrate infusion on perioperative blood loss and the amount of perioperative allogeneic blood transfusion in patients undergoing scoliosis surgery.

Recently, the inherent risks of blood, along with the continued rise in blood costs, activated the development and use of alternatives to blood transfusion. Fibrinogen concentrate may limit postoperative bleeding and lead to a significant reduction in allogeneic blood products transfusions in cardiac surgery and craniosynostosis surgery. However, the effect of fibrinogen concentrate in scoliosis surgery is still uncertain. Therefore, a prospective, randomized trial is designed to evaluate if the infusion of fibrinogen concentrate may reduce allogeneic blood transfusion in patients undergoing scoliosis surgery.

Patients older than 12y/o with adolescent idiopathic scoliosis planed for elective posterior scoliosis correction surgery will be enrolled for this study after informed consent. Patients will be randomly assigned to a treatment group or a control group. Functional fibrinogen will be measured using TEG 5000 (Haemoscope Corp, IL, USA) at the start of surgery and the results of FLEV and MA will be recorded. After pedicle screw placement, a second functional fibrinogen will be measured and the patients in treatment group will receive fibrinogen concentrate (FIBRORAAS, Shanghai RAAS Blood Products Co, Ltd, Shanghai, China) 30mg kg-1. For safety concern, the maximum fibrinogen concentrate administration for each individual shall not exceed either 2g. Patients in the control group will receive placebo treatment with normal saline. After 15 minutes from fibrinogen concentrate or placebo administration, a third functional fibrinogen measurement will be performed to assess the effect of treatment. The following treatment will be guaranteed by the standard protocol in the presence of ongoing bleeding.

Data includes all the demographics, preoperative conditions, procedure details, intraoperative data, and outcome measurements will be recorded. Additional data including FLEV and MA value, as well as fibrinogen values both preoperatively and at the arrival at wards. The primary endpoint of this study will be the total perioperative blood loss, and secondary endpoints will include: perioperative blood loss per fused level, intraoperative blood loss per fused level, the amount of postoperative drainage, the amount of postoperative drainage per fused level, total units of perioperative allogeneic pRBCs transfused, total volume of FFP transfused, total PLT units transfused. Safety endpoints will include operative mortality and perioperative thromboembolic complications.

Inclusion Criteria:

• patients diagnosed as adolescent idiopathic scoliosis
• planed for elective posterior scoliosis correction surgery at Peking Union Medical College Hospital

Exclusion Criteria:

• preoperative anemia
• preoperative congenital or acquired coagulopathy
• ongoing anticoagulation therapy or drug intake that could cause bleeding
• clinical signs or diagnosis of acute thromboembolism
• emergency surgery
• redo surgery

Coded data is anticipated to be shared with potential collaborators.

Anticipated that data from the study will become available within 5 years after publication of main data.

Data would only be shared with IRB approved collaborators.

After randomization, the unblinded independent investigator will be in charge of fibrinogen concentrate (drug) or placebo preparation, which will be performed in a laboratory next to the operating room. When the patient meets the inclusion criteria and is enrolled in the study, the functional fibrinogen tests will be done in the same laboratory by the same researcher, and drug or placebo will be prepared in sterile bags with opaque covers afterwards. Fibrinogen concentrate will be diluted in 100mL of sterile water or an equivalent volume of 0.9% saline solution as placebo and will be delivered to the operating room by the investigator. The anesthesiologists, the surgical staff, and the patients will all be blinded.