Hidden blood loss after hip and knee arthroplasty

Abstract

AIM：Hidden blood loss could greatly affect the recovery of total hip arthroplasty (THA) and total knee arthroplasty (TKA), especially the decrease in hemoglobin after TKA. In this study, the correlated mechanisms and clinical effect of hidden blood loss after THA and TKA were investigated.

METHODS: ①From March 2001 to May 2005, 41 patients (22 males and 19 females, aged 61-79 years) treated with THA and 37 patients (23 males and 14 females, aged 65-77 years) treated with TKA were selected. All arthroplasties were primary and unilateral, and the 24 hours fluid resuscitation was less than 2 000 mL. The informed consent was obtained from the subjects. ②Thirty-two of 41 patients undergoing THA received allogeneic store blood during and after operation. All patients undergoing TKA were given pueumatic tourniquet during operation but no blood transfusion. Blood routine examination was performed before and 2-3 days after operation to record haematocrit (Hct). Meanwhile, the body mass index (BMI) of all patients was calculated preoperatively. People with BMI ≤ 30 kg/m2 served as non-obesity group and > 30 kg/m2 served as obesity group. Using Gross formula, the true total blood loss was calculated depending on the height, body mass and pre-and post-operative Hct, and hidden blood loss was gotten by subtracting the visible blood loss from total loss. ③The correlation between visible and hidden blood loss was observed.

RESULTS: All 41 patients undergoing THA and 37 TKA were involved in the result analysis. ①Following THA, the mean total loss was 1 520 mL and the hidden blood loss 482 mL (32%). Following TKA, the mean total loss was 1 508 mL and the hidden blood loss was 776 mL (52%). The hidden blood loss between THA and TKA was significantly different (P < 0.01). ②No difference was found in the hidden blood loss between obesity and non-obesity patients in both THA and TKA (P > 0.05).

CONCLUSION: ①The hidden blood loss in TKA is far higher than THA. It is very important to supplement the blood volume during TKA for the insufficiency to regain general circulation although using blood re-infusion. ②It may improve clinical evaluation capabilities to estimate hidden blood loss and thus result in better patient care after joint arthroplasty.

Xiao P, Wu XJ, Liu HJ.Hidden blood loss after hip and knee arthroplasty.Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(4):635-638(China) [www.zglckf.com/zglckf/ejournal/upfiles/08-4/4k-635(ps).pdf]

摘要
目的：隐性失血对全髋关节置换术和全膝关节置换术后的恢复影响很大，尤其是全膝关节置换术后患者血红蛋白的下降往往与预期的结果相差很远。观察人工全髋关节置换术人工全膝关节置换术后隐性失血的相关机制及对预后的影响。
方法：①试验对象：选择2001-03/2005-05本院行全髋关节置换术的患者41例，男22例，女19例，年龄61~79岁；同期行全膝关节置换术的患者37例，男23例，女14例，年龄65~77岁。纳入标准：所有病例均为初次行单侧关节置换的患者，24 h 补液总量不超过2 000 mL，参与者对试验知情同意。②试验方法：41例行全髋关节置换术的患者中32例在术中和术后输入异体库存血。所有行全膝关节置换术的患者均在术中使用气囊止血带，未输血。术前及术后二三天均进行血常规检查，记录红细胞比容。术前计算出所有患者的体质量指数。体质量指数≤30 kg/m2 为非肥胖组，体质量指数>30 kg/m2 为肥胖组。通过Gross方程，根据身高、体质量和手术前后的红细胞比容计算所有患者的总失血量，减去显性失血部分即得隐性失血。③试验评估：观察两组术后显性和隐性失血的相关情况。
结果：纳入全髋关节置换术41例和全膝关节置换术37例，均进入结果分析。①全髋关节置换术组患者的实际失血总量平均为1 520 mL，隐性失血为482 mL，占总量的32%。全膝关节置换术组患者的实际失血总量平均为1 508 mL，隐性失血为776 mL，占总量的52%。两组隐性失血量相比，差异有显著性意义（P < 0.01）。②全髋关节置换术组与全膝关节置换术组肥胖患者和非肥胖患者的隐性失血量相比，差异均无显著性意义（P > 0.05）。
结论：①全膝关节置换术隐性失血远较全髋关节置换术高，且使用引流血回输仍不能完全满足机体恢复循环的需要，应特别注意及时补充血容量。②对隐性失血的正确认识有助于提高临床评估能力，可帮助关节置换患者顺利度过围手术期，有利于术后开展早期关节功能训练。
关键词：髋关节；膝关节；关节成形术；置换

肖鹏，吴学建，刘宏建.人工关节置换术后隐性失血的相关分析[J].中国组织工程研究与临床康复，2008，12(4):635-638
[www.zglckf.com/zglckf/ejournal/upfiles/08-4/4k-635(ps).pdf]