Effect Of Preoperative CRP On Hidden Blood Loss After Total Knee Arthroplasty

Objective: To study the effect of preoperative C-Reactive Protein(CRP)level on Perioperative Hidden Blood Loss(PHBL)in unilateral Total Knee Arthroplasty(TKA).Method: Clinical data of 49 patients with unilateral TKA admitted from October 2016 to March 2018 were collected for retrospective analysis.According to preoperative CRP levels were divided into two groups,CRP normal group(CRP<1mg/dL)and elevated CRP group(CRP?1mg/d L).22 patients in the elevated CRP group and 27 patients in the normal CRP group.The patient's sex,age,height,weight,bone mineral density,preoperative CRP,hematocrit(HCT),hemoglobin(Hb),and Erythrocyte Sedimentation Rate(ESR)were recorded.According to the Gross equation,the patient's absolute value and percentage of PHBL were calculated,and the effect of different preoperative CRP levels on the absolute value of PHBL and the percentage of PHBL in patients with TKA was compared.Results: The absolute PHBL(936.19±239.13)ml in the preoperative CRP-elevated group was higher than the absolute PHBL value(763.52±218.01)ml in the preoperative CRPnormal group.The difference in absolute values of PHBL between the two groups was statistically significant(P=0.011).The percentage of PHBL in patients with preoperative CRP elevation was(21.85±3.84)% higher than that of patients with normal preoperative CRP(17.40±4.85)%.The difference in PHBL between the two groups was statistically significant(P=0.001).Univariate analysis showed that absolute value of PHBL in patients with TKA was related to CRP,BMI,and gender,and the percentage of PHBL in patients with TKA was related to CRP.Multiple linear regression analysis showed that the factors affecting the absolute value of PHBL in patients with TKA included CRP,BMI and gender.The influence factor of the percentage of PHBL in patients with TKA is CRP.Conclusion: Elevated preoperative CRP levels cause increased PHBL in patients with TKA.Elevated preoperative CRP levels are risk factors for increased PHBL in TKA patients.Clinicians needs to pay more attention to the hidden blood loss in patients with higher preoperative CRP.