膝关节置换术后患肢体位对术后失血量的影响

Efficacy of knee position in reducing blood loss following total knee arthroplasty

目的探讨初次人工全膝关节置换术(TKA)术后屈膝体位对失血量的影响。方法从2014年5月到2015年5月收集拟于武汉大学人民医院行初次单侧膝关节置换者,将纳入的90例患者随机分成A、B、C三组,每组30例。三组病例术后均屈髋抬高30°,其中A组术后72 h内膝关节处于完全伸直位,B组术后72 h内膝关节处于屈膝30°体位,C组术后72 h内维持屈膝60°体位。所有患者术后均放置负压引流袋48 h,记录各组引流量,术后第1、3、5天血红蛋白水平,术后第3天、1周、6周膝关节活动度。记录各组伤口愈合情况、输血人数以及术后3个月并发症的情况。对于计量资料用单因素方差分析,各组间两两比较用LSD-t检验;计数资料用卡方检验或Fisher精确检验,P<0.05表示差异有统计学意义。结果三组患者术后48 h引流量比较差异有统计学意义(F=78.378,P<0.05);各组间两两比较A组与B、C组差异均有统计学意义(P<0.05),B、C两组无明显差异(P>0.05)。三组术后第1、3、5天血红蛋白水平差异有统计学意义(F=10.694,P<0.05;F=23.557,P<0.05;F=21.594,P<0.05),其中A组与B、C两组差异均有统计学意义,B、C两组无明显差异;术后第3天、1周膝关节活动度差异有统计学意义,两两比较差异均有统计学意义(F=45.030,P<0.05;F=29.013,P<0.05);三组术后6周膝关节活动度差异无统计学意义(F=1.488,P>0.05)。术后各组伤口愈合情况可,无输血,所有患者均无感染、下肢深静脉血栓等并发症发生。结论 TKA术后通过屈膝体位可以有效减少失血量,但屈膝体位减少失血量的作用并不和角度大小正相关。

Objective To assess the effect of knee flexion on blood loss and range of motion（ ROM） after primary total knee arthroplasty（ TKA）. Methods Ninety consecutive TKA patients were randomized into group A,group B and group C in Renmin Hospital of Wuhan University from May 2014 to May 2015,30 cases in each group. The operated lower limb was elevated for 30°with the hip flexed. The involved knee was extended in group A,which was flexed to 30°in group B and flexed to 60°in group C for72 h post-operatively. Wound drainage of postoperative 48 h was recorded; the post-operative haemoglobin of day 1,day 3 and day 5,the postoperative ROM of day 3,day 7,and the 6^（th） week were also recorded and assessed. The wound condition,the proportion of the patients who had blood transfusion and all the complications within three months post-operatively were recorded. The measurement data were tested by One-Way one-factor analysis of viarance（ ANOVA）,and the comparisons between two groups were tested by least significant difference（ LSD）-t method. The count data were tested by Chi-square test or by Fisher＇s exact test. The difference at the level of P〈0. 05 was considered statistically significant. Results Significant differences of wound drainage were observed among the groups（ F = 78. 378,P〈0. 05）. The significant differences were found in the drainge volume at postoperative 48 h when group A was compared with group B and group C respectively（ P〈0. 05）; no significant difference was found between group B and group C（ P〈0. 05）. Significant differences were also observed among the groups in haemoglobin at day 1,day 3,and day 5 postoperatively（ F = 10. 694,P〈0. 05; F = 23. 557,P〈0. 05; F = 21. 594,P〈0. 05）; significant differences were found when group A was compared with group B and group C respectively; while no significant difference was found between group B and group C. In ROM,the differences among the groups at post-operative day 3 and day 7 were significant,which were presented while each two groups were compared（ F = 45. 030,P〈0. 05; F = 29. 013,P〈0. 05）. The ROM results were similar among the groups in the post-operative 6thweek（ F = 1. 488,P〈0. 05）. The wound condition was good and no blood transfusion in each group. There was not any complication including deep vein thrombosis or pulmonary embolism. Conclusion This study indicates that knee flexion after TKA may reduce blood loss after the surgery,however,the efficacy was not positively related to the flexion angle.