Comparison between two methods of drain clamping after total knee arthroplasty.

INTRODUCTION: To study the clinical outcome of two methods of drain clamping after total knee arthroplasty and to determine the effect on blood loss and blood transfusion.

PATIENTS AND METHODS: A prospective study involving 73 patients, randomized into two groups. Group 1 included patients in whom the drain was clamped for 1 h postoperatively, after which it was released and kept open for 48 h. Group 2 included patients in whom the drain was clamped and released for 10 min every 2 h for 24 h. The drain was removed at 48 h in both groups. Patient's demographic details, intraoperative and postoperative blood loss, and haemoglobin values on the preoperative and postoperative days (1, 4, 7, 14) were recorded.

RESULTS: The mean postoperative drainage in group 1 was 520.65+/-170 ml, which was significantly higher than that of group 2, 367.62+/-141.1 ml (p < 0.05, Student's t-test). The drain charting shows 65% of drainage volume occurs in the first 8 h in both groups. The study suggests a reduction in the incidence of blood transfusion in the 2-hourly groups, although it was not statistically significant. There was a difference in the haemoglobin drop between both groups, but statistically the p value was marginally above 0.05 (p = 0.086) and hence not significant.

CONCLUSION: The method of 2-hourly clamping of drain and release for 10 min significantly reduces postoperative blood loss, without any added increase of complication, after total knee arthroplasty.