Is Intraoperative Autotransfusion In Mild-bleeding Surgery Useful Or Harmful? A Randomized Controlled Trial

Objectives:The volume of blood used for transfusion in China continues to soar as a result of the increasing amount of surgery. Because of the shortage of blood products and the complications of allogeneic transfusion, autologous transfusion has been advocated in China. Cell Salvage devices for intraoperative autotransfusion, such as Cell Saver (CS), is commonly used in a wide variety of surgical procedures. However, the CS indications suggested in domestic and international guidelines are inconsistent in the extent of surgery bleeding, and doctors tend to prepare CS when less blood loss is anticipated. To investigate the effect of cell saver blood in patients undergoing mild-bleeding surgery (defined as blood loss less than20%estimated blood volume based on body weight) compared with non-CS transfusion patients. Tissue perfusion, in vivo inflammatory level and postoperative recovery were studied to determine whether the CS transfusion is reasonable in this setting.Methods:Our study comprised patients scheduled for posterior lumbar surgery at Peking Union Medical College Hospital. Inclusion criteria were defined as follows:age of18-75years, ASA I or II, estimated blood loss less than20%blood volume. Exclusion criteria included preoperative anemia, severe cardiovascular or cerebrovascular disease, immune disorder, infectious disease, and a history of surgery or transfusion within3months. Patients were randomized into two groups according to computer-generated random table numbers. The transfusion group was given the Cell Saver blood intraoperatively, while the control group received equal volume of colloid solution instead. Blood samples were obtained at:before induction of anesthesia, the end of the main steps in the surgery, half an hour,1day and3days after surgery. The parameters including complete blood count, venous blood gas, cerebral oxygenation, and inflammatory factors (lnterleukin-6, lnterleukin-10and neutrophil elastase) were compared between the two groups, together with the postoperative recovery such as post-op body temperature, drainage, VAS pain scores, chief complaint (dizziness, fatigue or palpitation), wound healing, post-op ambulation time, complication and length of stay. Results:41patients scheduled for elective lumbar surgery were enrolled with all their informed consent.3cases were excluded for intraoperative massive bleeding (>1000ml), intraoperative Hb<90g/L and multiple missing data. The remaining38cases were randomized into the transfusion group (n=19) and the control group (n=19). The two groups were comparable in demographic data, baseline conditions and intraoperative blood loss. In the transfusion group, Hemoglobin was116.5±10.7g/L at post-op1/2hr and115.4±12.3g/L on post-op day1, both elevated compared with intra-op (106.6±12.6g/L, P<0.05). On post-op day3, the statistical differences of hemoglobin no longer existed. Lactate was elevated at post-op1/2hour (2.5±1.0mmol/L) versus pre-op values (1.3±0.6mmol/L)(P<0.05) in the control group, while the trend was absent in the transfusion group. IL-6on post-op day1was elevated than pre-op only in the control group (151.2±73.7ng/L vs.141.0±94.6ng/L, P<0.05).11-10on post-op day3was elevated than pre-op only in the transfusion group (338.5±137.3ng/L vs.326.2±134.1ng/L, P<0.05). There were no significant differences in postoperative hemoglobin, lactate, cerebral oxygenation, white blood cells and inflammatory factors between the two groups. The allogeneic transfusion rates of the control group and the transfusion group were0and5.3%respectively. No statistically differences were observed in fever, pain, chief complaint, wound healing, post-op ambulation time or length of stay between the two groups.Conclusions:The use of CS in healthy adult patients undergoing mild-bleeding surgery only temporarily improved hemoglobin and tissue oxygenation, with little influence on inflammation and allogeneic transfusion rate, as well as prognosis amelioration. CS may be not cost-effective under this circumstance. The application of CS should be considered with caution when mild blood loss is anticipated in our research setting.