Saturday, February 15, 1997
A study has found that most of the autologous blood donated by patients scheduled for total knee arthroplasty (TKA) is not needed and is discarded.
Researchers at the University of Arizona Health Sciences Center said that 30 patients scheduled for unilateral TKA donated 56 units of blood; only six needed an autologous blood transfusion in the postoperative period. Seventy-one patients scheduled for bilateral TKA donated a total of 159 units; 42 donors required an autologous blood transfusion in the postoperative period.
The high incidence of unutilized/discarded blood-80 percent in the unilateral TKA group and 50 percent in the bilateral TKA group-has resulted in a discontinuation of autologous donation in patients undergoing unilateral TKA, James B. Benjamin, MD, orthopaedic surgery section, the University of Arizona Health Sciences Center, said Friday. Patients undergoing bilateral arthroplasty still participate in preoperative autologous donation (PAD) program with a maximum contribution of two units of blood.
In reporting the study results in scientific paper 264, Dr. Benjamin said the mean blood loss as measured by drain output for all patients in the unilateral group was 440 milliliters. However, an average of 585 milliliters was lost in those patients who required transfusion, compared with 424 milliliters in those patients who were not transfused. Fourteen patients in this unilateral group received some type of postoperative blood salvage.
The mean blood loss in the bilateral group was 706 milliliters. An average of 811 milliliters was lost in those patients who required transfusion, compared with 606 milliliters in those patients who were not transfused. Thirty patients in the bilateral group underwent postoperative blood salvage.
Overall, 52 of the 178 patients who underwent knee arthroplasty received a postoperative banked blood transfusion. Forty-eight patients received an autologous transfusion and eight received an allogenic transfusion (four of these patients received both autologous and allogenic blood). Forty-eight of 101 patients who participated in the PAD program underwent postoperative transfusion while only four of 77 nondonors required transfusion.
In total, 90 of the 215 autologous units collected were transfused and 125 units were discarded. Fifteen units of allogeneic blood were transfused.
"Autologous blood donation has been proven to decrease the incidence of allogenic transfusions and the associated risk of disease transmission," Benjamin said. "The cost of an autologous unit of blood in most centers is higher than that of allogeneic blood due to the additional handling costs and the loss of nontransfused units that are discarded.
"Our enthusiasm for this technology may have led to over-utilization in many settings. Additionally, many managed care insurance programs are no longer covering the cost of autologous blood donation."
Brent Baranko, MD, University of Arizona Health Sciences Center, also was a co-author of the study.
| Home | 1997 Academy News Feb. 15 Index B |
Last modified 27/January/1997