Comparison of effectiveness of Different doses of prophylactic intravenous fibrinogen versus normal saline on intraoperative bleeding in posterior spinal fusion surgery

Determining the appropriate dose of prophylactic fibrinogen effective in reducing the amount of intraoperative bleeding

A clinical trial , control group, parallel groups, double-blind, randomized, phase 3 on 120 patients, randomized permutation block was used for randomization.

Each patient will have a sealed envelope containing data group information and will be opened in the operating room by a designated nurse. The anesthesiologist prepares and prescribes the drugs for everyone. Patients undergo induction of similar anesthesia after pre-oxygenation. The amount of bleeding during the operation is calculated from the weight of the gases and the amount of blood in the suction. 15-30 minutes before surgery, all three groups receive two 50 cc infusion syringes (the first group fibrinogen and normal saline, the second group two fibrinogen syringes and the control group two normal saline syringes). At the end of the operation, the total amount of bleeding, the need for transfusion, the number of pack injection units, and the length of the surgery are evaluated.

No history of drug allergies, thromboembolism and coagulation disorders, use of anticoagulants, history of blood disorders and coagulopathy,

After induction of anesthesia in group F1, 1gr and in group F2, 2gr of fibrinogen and in the control group the same normal volume of saline will be injected intravenously. All patients are monitored by standard and depth of anesthesia. And will have intermittent IPC. All will be operated on by a PSF surgeon. The total amount of bleeding, the need for transfusion, the number of pack cell injection units and the length of surgery are assessed.

Intraoperative bleeding rate, comparison of different doses of prophylactic fibrinogen

Permuted Randomized Blocks :In this method, 10 random blocks are generated by computer. Each block includes 5 people in the intervention group and 5 people in the control group. The order of these people is randomly arranged by computer and people are assigned to groups in the same way. At the end of each block, a new block of 10 is produced and this process will continue until the final sample volume is reached.

Forms with numbers 1 and 2 are used in packaged envelopes to group patients, which are given to patients randomly and patients do not know about the envelopes. After entering the envelope operating room by the anesthesiologist in charge of the patient Opened and according to the intervention group, the drug that was prepared in advance is given to the clinical caregiver for injection. The clinical caregiver is not aware of the grouping. The evaluator and recorder of the results and the person analyzing the data are also unaware of the grouping.