Transfusion of Autologous, Hydroxyethyl Starch-Cryopreserved Red Blood Cells Ernst-Peter Horn, MD*, Andreas Sputtek, MDt, Thomas Standl, MD*, Birgit Rudolf, MD*, Peter Kiihnl, MDt, and Jochen Schulte am Esch, MD* Departments of *Anesthesiology and tTransfusion Medicine, University Hospital Eppendorf, Hamburg, Germany In this prospective, randomized study, we investigated the safety and efficacy of the transfusion of hydroxyethyl starch (HES) cryopreserved red blood cells (RBC) com- pared with the transfusion of liquid-stored RBC in pa- tients undergoing major orthopedic or urologic surgery. Thirty-six patients donated autologous blood 35 ? 6 days before elective surgery. Only the first of 3.5 ? 1.3 donated units of RBC was randomly assigned to be stored in the liquid state at 4°C in phosphate / adenine/ guanosine / glucose/saline-Mannitol or frozen below -130°C by means of liquid nitrogen after the addition of HES (molec- ular weight 200,000 Dalton, degree of substitution 0.5, fi- nal concentration 11.5% wt / wt) as a cryoprotectant. After induction of anesthesia, patients donated 900 mL of autol- ogous blood before they received one unit of liquid-stored RBC in Group 1. In Group 2, one unit of cryopreserved autologous RBC was transfused after removal of the cryo- protectant HES. In Group 3, patients received one unit of cryopreserved RBC without any manipulation after thawing. Patients in Groups 1 and 2 received addi- tional 500 mL of 10% HES. Hemodynamic variables, arte- rial blood gases, plasma hemoglobin, and arterial lactate concentrations were measured after the induction of anes- thesia, after hemodilution, and at lo-min intervals after transfusion of the respective RBC concentrate over a pe- riod of 40 min. Skeletal muscle tissue oxygen tension was measured in the quadriceps muscle using an automati- cally stepwise-driven oxygen partial pressure electrode. We found no differences among groups concerning de- mographics, arterial blood gas values, and lactate concen- trations and observed no adverse reactions after transfu- sion of the conventionally stored or cryopreserved RBC. Hemodynamic variables did not differ among groups, with the exception of an increased mean arterial blood pressure after the transfusion of cryopreserved unwashed RBC. In all groups, the skeletal muscle tissue oxygen ten- sion remained constant after hemodilution and increased after transfusion of either washed or unwashed cryopre- served RBC. Although the free plasma hemoglobin con- centration remained constant after the transfusion of liquid-stored RBC (26 t 8 mg / dL), the plasma hemoglo- bin concentration increased twofold after the transfusion of cryopreserved washed RBC (60 + 12 mg/dL) and threefold after transfusion of cryopreserved unwashed RBC (98 + 20 mg/dL). The authors conclude that transfu- sion of one unit of RBC after cryopreservation with HES is safe and well tolerated by patients. Intravascular volume replacement and skeletal muscle oxygenation characteris- tics by erythrocytes did not differ between liquid-stored and cryopreserved RBC. Implications: This study exam- ined whether a colloid should be used to store blood. Our data suggest that the transfusion of one unit of red blood cells after cryopreservation with hydroxyethyl starch is safe and well tolerated by patients. The effects of intravas- cular volume replacement and skeletal muscle oxygen- ation provided by red blood cells after liquid storage or cryopreservation were not different. (Anesth Analg 1997;85:73945) C ryopreservation of red blood cells (RBC) at low temperatures allows for nearly unlimited stor- age. Transfusion of cryopreserved human RBC was first reported by Mollison and Sloviter in 1951 (1). Posttransfusion survival studies of RBC demonstrated 95% survival rates for erythrocytes in excess of 10 Presented in part at the annual meeting of the American Society of Anesthesiologists, New Orleans, LA, October 22-25, 1996. Accepted for publication June 18, 1997. Address correspondence and reprint requests to E.-P. Horn, MD, Department of Anesthesiology, University Hospital Eppendorf, Martinistreet 52, 20246 Hamburg, Germany. Address e-mail to EPHORNQCompuServe.Com. years after cryopreservation (2). As a consequence, cryopreservation of RBC allows long-term donation of autologous blood because the blood program can start independent from the day of the planned operation. In addition, cryopreservation and quarantine of homol- ogous blood may be helpful to reduce the risks of hepatitis C or human immunodeficiency virus trans- mission. Because viral inactivation techniques for RBC are not available, the safety of RBC can be improved by either more careful donor selection or improved testing (3,4). Unfrozen RBC can only be quarantined for seven weeks. This is too short a period to safely exclude the infectivity of a unit of RBC donated by a 01997 by the International Anesthesia Research Society 0003-2999/97/$5.00 Anesth Analg 1997;85:73945 739