Postoperative blood salvage in total knee arthroplasty using the Solcotrans autotransfusion system.

One hundred forty-four patients who underwent primary total knee arthroplasty were examined in a prospective controlled study to determine the efficacy and safety of a postoperative wound drainage autotransfusion system (Solcotrans, Smith & Nephew Richards, Memphis, TN). The patients were divided into two groups: control group 1 comprised 88 (61%) patients who either received a Hemovac disposable drainage system (63 patients) or the Solcotrans system and had inadequate drainage for autotransfusion (25 patients). Experimental group 2 comprised 56 (39%) patients who received a Solcotrans drainage system and were autotransfused. The Solcotrans proved itself safe. No sepsis, transfusion reactions, or coagulopathies were associated with autotransfusion, which averaged 524 mL. There were no significant differences between groups 1 and 2 when comparing preoperative and postoperative hemoglobins and hematocrits. The Solcotrans system did not lower homologous blood requirements. Only 1.6% (2 patients) of all patients who autodonated at least 2 units of autologous blood (122 patients) were in need of a homologous blood transfusion in the postoperative period. Thus, although safe, the Solcotrans system was not proven effective in the management of primary total knee arthroplasty patients.

Treatment of nonunion with constant direct current.

Laboratory experiments show the following relationships between electricity and bone: (1) stressed bone exhibits electronegativity in areas of compression, (2) living, nonstressed bone exhibits electronegativity in areas of bone growth and healing, and (3) the application of low magnitude direct current to bone induces osteogenesis at the negative electrode or cathode. Based on the above principles, a clinical study was performed in which 10-20 microamperes of constant direct current was used in treating nonunion in 57 patients. The results suggest that specific electrical parameters are required for successful osteogenic stimulation in patients. When these electrical parameters are met, a successful healing rate of 70 per cent can be achieved in treating nonunion with direct current. As experience is gained with this new technique in the treatment of nonunion, the results should improve even further. Basic studies exploring the mechanism(s) whereby electricity induces osteogenesis are opening new vistas into our understanding of bone growth and repair. The extension of these basic studies has far-reaching clinical implications.