Investigation of the use of drained blood reinfusion after total knee arthroplasty: a prospective randomised controlled study.

PURPOSE: To compare the use of a blood salvage and reinfusion system with standard allogeneic blood transfusion after total knee arthroplasty--a procedure associated with significant postoperative blood loss. METHODS: Between June 2002 and May 2004, 60 patients undergoing total knee arthroplasty were randomly allocated into a reinfusion group (n = 26) or a control group (n = 34). Patients in the reinfusion group had their blood reinfused from drains within 6 hours of surgery. Both groups received allogeneic blood transfusions according to specified transfusion criteria if the haemoglobin level fell below 90 g/l, or in the presence of severe anaemic symptoms. Haemoglobin levels and drain output were recorded daily for 3 consecutive days after surgery. RESULTS: There was no significant difference between the 2 groups in demographic data, drain output, total blood loss, and mean postoperative haemoglobin levels. Significantly more allogeneic blood was required by the control group than by the reinfusion group (p = 0.022). CONCLUSION: Postoperative reinfusion of drained blood reduced the need for blood transfusion after total knee arthroplasty, while having an effect on postoperative haemoglobin level equivalent to standard allogeneic blood transfusion.

The shape and size of femoral components in revision total hip arthroplasty among Chinese patients.

OBJECTIVE: 39 sets of preoperative hip X-rays were studied to find out whether Chinese patients need revision femoral components with a different shape and size from western patients. METHODS: From July 1998 to June 2001, the pre-revision X-rays of 39 revision total hip replacements among 38 Chinese patients (21 men and 17 women) were studied. The component size that produced the best distal canal-filling in the anteroposterior X-ray was determined by using templates of 200-mm femoral components used commonly for Caucasian patients. RESULTS: The diameter of the component needed was 13.5 mm or less in 54% of cases, compared with only 17% for Caucasian patients as reported in the literature (p<0.01). When lateral templates of the corresponding size were put over the lateral X-rays, the anterior cortex of the 200-mm straight stem was shown to have thinned by 2.0 mm or more in 36% of hips; for 200-mm bowed stem, there was thinning of the anterior cortex by 2.0 mm or more in only 5% of hips (p<0.01). CONCLUSION: Chinese patients are likely to need smaller femoral components than Caucasian patients, and may benefit from bowed-stem components in femoral revision.