Comparison between two methods of drain clamping after total knee arthroplasty

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.

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.

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.

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.