Abstract
Total knee arthroplasty has been associated with substantial blood loss in the perioperative period necessitating a substantial risk for blood transfusions. There are various methodologies utilized to decrease postoperative anemia and minimize the need for allogeneic blood transfusions. These include autologous pre-donation, the use of erythropoietin and the use of perioperative cell salvage. Although all of these are successful in decreasing postoperative anemia, there is still a significant risk of allogeneic blood transfusions in the postoperative period. This is a retrospective review of a consecutive series of total knee replacements investigating blood loss and the need for postoperative blood transfusions utilizing MIS surgical techniques and Symphony (tm) platelet gel as the sole means of blood conservation.
PATIENT DEMOGRPAHICS
Between January 1, 2005 to December 31, 2005, 83 total knee arthroplasties were performed in a variety of community hospitals by a single orthopedic surgeon. The mean age was 64 years (SD 11.6, range 28-90) and the mean BMI was 34.1 (SD 7.6, range 21.3 to 53.4). 71% of the patients were females and 29% males.
All patients, regardless of deformity, age or size, had a quad sparing MIS total knee arthroplasty performed utilizing cemented posterior stabilized components and all patellae were resurfaced. No patients pre-donated any blood products or had erythropoietin and no drains were utilized postoperatively. All patients had application of Symphony (tm) platelet gel prior to the interoperative release of the tourniquet. All patients received Coumadin on the day of surgery and were managed for four weeks postoperatively to keep their INR approximately 2.0.
RESULTS
The mean preoperative hemoglobin was 14 (SD 1.2, range 10.7 to 16.6). The average postoperative hemoglobin was 10.0 (SD 1.1, range 8.0 to 14.2). The average drop in hemoglobin was 4.0 with a SD of 1.1. A total of two patients were transfused in this series of 83 patients for a total transfusion rate of 2.4%. The average length of stay was 3.4 days with the SD of 3.7. No patients suffered a CVA, myocardial infarction or pulmonary embolus in the two-month postoperative period.
CONCLUSIONS
The results show that even utilizing MIS surgical techniques and Symphony (tm) platelet gel, there is still substantial blood loss in patients undergoing unilateral total knee arthroplasty utilizing cemented components with a mean drop of hemoglobin of four grams or 20% of their mean preoperative hemoglobin. However, in spite of significant loss of hemoglobin, most patients tolerated the postoperative anemia very well and there were no complications in this series related to anemia and this did not prolong their length of stay, which was an average of 3.4 days. Only a very low percentage of patient's in this series required a postoperative transfusion (2.4%). This report supports the continued use of MIS surgical techniques along with Symphony (tm) platelet gel to minimize the need for postoperative transfusions in total knee arthroplasties.
