[Intraoperative hemodilutional autotransfusion using a closed circuit for patients of Jehovah's Witness].

We conducted hemodilutional autotransfusion using a closed circuit combined with a cell washing reinfusing system (Cell Saver) for two surgical patients of Jehovah's Witness. One was a 12 yr-old boy for extirpation of the teratoma in the anterior mediastinum and another was a 44 yr-old woman for left total hip replacement. The patients and their relatives had consented to the use of blood substitutes, hemodilutional autotransfusion using a closed circuit and Cell Saver. We devised a closed circuit system for hemodilutional autotransfusion combined with Cell Saver, in which two pumps for blood transfusion were used; one was for drawing blood from the femoral or the internal jugular vein and the other for returning blood to the peripheral vein. Blood volume in a bag interposed in the closed circuit was easily controlled by adjusting the speed of each pump. Blood collected from the surgical field by Cell Saver was also led to the bag. Acid citrate dextrose solution was infused into the closed circuit from the site close to the blood drawing. Both of our surgical patients were safely managed without homologus blood transfusion, although there remained some problems concerning the use of anticoagulants.

Hemodilution as a method to reduce transfusion requirements in adolescent spine fusion surgery.

STUDY DESIGN: A case-control study. OBJECTIVES: 1) To determine if hemodilution adequately meets the transfusion needs in children who undergo posterior spinal fusion for idiopathic scoliosis and 2) to compare the efficacy of the various methods used to reduce the risk of allogeneic blood transfusion at the authors' institution. SUMMARY OF BACKGROUND DATA: Methods to reduce blood loss and avoid allogeneic blood transfusion caused by extensive spinal surgery in adolescents include 1) autologous blood predonation, 2) controlled hypotensive anesthesia, 3) intraoperative salvage of shed blood (cell saver), 4) acute normovolemic hemodilution, and 5) transfusion decisions by clinical judgment rather than by a preset value of hemoglobin. Although all methods have some efficacy, it is not clear which methods, separate or combined, are best in the adolescent scoliosis population. METHODS: Hemodilution, hypotensive anesthesia, and cell saver were used in 43 children between June 1996 and July 1997. A comparison group (43 children) underwent similar surgery with hypotensive anesthesia and cell saver, but no hemodilution (between July 1995 and December 1996). These two groups were similar with respect to means of age, levels of instrumentation, magnitude of curvature, estimated blood volume, mean arterial pressure, duration of surgery, duration of anesthesia, estimated blood loss, volume returned from cell saver, volume in the hemovac drain, and length of hospitalization. The groups differed in preoperative hemoglobin and hematocrit and in volume of crystalloid used. RESULTS: Transfusions were given to 34 of 43 patients (79%) in the nonhemodilution group. These patients received 61 units of packed cells (57 autologous, 2 donor directed, and 2 allogeneic). In comparison, 16 of 43 patients (37%) in the hemodilution group required transfusion. They received 16 units of packed cells (15 autologous and 1 allogeneic). There was no significant difference between the groups with respect to postoperative hemoglobin and hematocrit immediately after surgery (hemodilution, 10.2/29.2; nonhemodilution, 10.0/29.1), postoperative day 1 (hemodilution, 9.2/26.9; nonhemodilution, 9.2/27.3), and postoperative day 2 (hemodilution 9.0/26.4; nonhemodilution, 9.2/27.1). There were non complications related to the technique of hemodilution in the 43 patients of this group. Cell saver was used in all patients, but sufficient volume to return blood to the patient was available in only 23 hemodilution patients (mean volume, 230 mL) and 25 nonhemodilution patients (mean volume, 215 mL). In only two patients of each group (< 5%) did the volume returned prevent the absolute need for additional transfusions. CONCLUSIONS: Hemodilution was safely used as a method to satisfy the perioperative transfusion requirements of adolescents undergoing extensive spinal surgery. By allowing patients to arrive at surgery with a higher preoperative hemoglobin and hematocrit, and by decreasing the quantity of predonated autologous blood-collected and therefore used, the hemodilution method may indirectly decrease the quantity of postoperative autologous transfusions in this population. Cell saver was not shown to be effective, and its selective use is recommended.

[Reduction in the use of donated blood in surgical medicine]. / Reduktion des Fremdblutverbrauchs in der operativen Medizin.

After rapid changes in transfusion practice over the past few years, blood conservation techniques have become standard in modern perioperative management. As a result, the amount of homologous blood products transfused has been markedly reduced in some types of surgical procedures. Provided that skillful surgical technique is applied and the use of blood products is restricted, autologous transfusion techniques (predonation of autologous blood, preoperative plasmapheresis, acute normovolaemic haemodilution, and intra- and postoperative blood salvage) can be performed with an acceptable risk for patients. In addition, stimulation of erythropoiesis with recombinant human erythropoietin, supplemental iron therapy, and improving haemostasis by aprotinin may further reduce homologous blood requirements. All patients undergoing elective surgery have to be informed about the side effects of transfusion of homologous blood products and the possibility of blood-saving methods. An individual blood conservation plan, based on the patient's status and surgery, the equipment available, and personal experience should be worked out by the responsible anaesthesiologist, whereby a combination of different methods may be most effective. If storage is necessary, autologous blood products should be preparated like homologous products. The feasibility of predonation and retransfusion of autologous blood in patients with infectious diseases like hepatitis or acquired immune deficiency syndrome and the amount of labaratomy testing are still under discussion. Although blood conservation programs are time-consuming and more expensive, they reduce the various risks of using homologous blood products.

[Preoperative hemodilution as a possibility in autologous blood transfusion. A report of experiences]. / Die präoperative Hämodilution als eine Möglichkeit der autologen Transfusion. Ein Erfahrungsbericht.

The various methods of autologous blood donation are gaining importance in clinical practice. Acute preoperative isovolaemic haemodilution represents a cost-cutting and readily practicable option. It is a method that brings positive haemodynamic effects and improves the blood's flowing properties by lowering its viscosity and raising cardiac output, as well as avoiding the dangers associated with foreign blood transfusion. Risks to the patient can largely be eliminated by keeping an eye out for contra-indications and ensuring careful perioperative monitoring. The successful use of this method depends on a clear organizational concept and close collaboration between surgeons, anaesthesists and transfusions specialists.

[Original technic for preoperative hemodilution permitting deferred autologous transfusion (apropos of 106 cases)]. / Technique originale d'hémodilution préopératoire permettant la transfusion autologue différée (à propos de 106 cas).

To carry out normovolemic haemodilution in the best security conditions we elaborate a new method of preoperative haemodilution. Collection of red cell concentrates and adequate compensation are made either in the blood bank or at the patient's bed side. There are two ways of proceeding: *manual plasmapheresis technic is used for the collection of less than 450 ml packed red cells; *collection of more than 450 ml packed red cells is carried out on a PCS Haemonetics cell separator. CPD autologous red cells concentrates prepared in that way can be stored to meet the patient's need during and after the operation. The patient is identified as donor and receiver as regards laboratory analysis and computer treatment as well. Information's transmission between blood bank hospital and clinics is secured with the same document. This method enables homologues transfusion save and completes autologous transfusion in 68% cases among 106 patients. It is to be noticed that none of the 98 haemodiluted patients suffered from thrombosis.