Effects Of Serum Protein Levels On Postoperative Wound Healing In Elderly Patients After Total Knee Arthroplasty

Background:Total knee arthroplasty(TKA)is a common treatment for degenerative knee diseases in mid and late stage.Elderly people are the main group of TKA.However,due to the decline of physiological function and the increased risk of malnutrition,the elderly patients are more likely to have postoperative complications such as poor wound healing.The poor wound healing not only strongly influence the postop erative recovery,but also significantly increase the economic burden of patients and length of stay.Therefore,it is of great clinical significance and economic value to improve the rate of wound healing in elderly patients with TKA.Studies have shown that the nutritional status of patients is an important factor affecting the poor wound healing of TKA,serum protein levels are key laboratory nutrition indicators for assessing nutritional status.Some studies have reported a correlation between poor wound healing and albumin,transferrin,or other laboratory indicators,limited specific serum protein indicators were included,and the relationship between serum protein indicators and poor wound healing was not clear enough.and previous studies have paid little attention to the special group of elderly patients with high nutritional risk.In addition,there is a lack of scientific evidence for clinical nutritional intervention study of protein preparation.Therefore,to further explore the effects of serum protein levels on postoperative wound healing in elderly patients after total knee arthroplastyand and to investigate the effects of nutritional intervention on improving wound healing,have important clinical significance of reducing the incidence of poor wound healing in elderly patients with TKA.Objective: A retrospective cohort study was conducted to collect the electronic medical records of elderly TKA patients from several hospitals,and to investigate the correlation between serum protein levels in perioperative period and postoperative wound healing,making it clear that the effects of serum protein on postoperative wound healing in elderly patients with TKA;Perioperative nutritional intervention of whey protein was conducted on elderly patients after TKA in order to reduce the incidence of postoperative poor wound healing,and provide evidence and strategies for the promotion of postoperative wound healing and the rehabilitation of postoperative joint function in elderly patients with TKA.Methods:1.Retrospective study on the effects of serum protein levels to postoperative wound healing in elderly patients with TKA1.1 Data collectionUse convenient sampling method to choose 7 hospitals for data collecting,which included: Xinqiao Hospital of Third Military Medical University(TMMU),Daping Hospital of TMMU,the First and the Second Affiliated Hospital of Medical University of Chongqing,Chongqing Provincial People's Hospital,Qijiang County People's Hospital and Guizhou Provincial People's Hospital.And according to the inclusion and exclusion criteria,information and related data were collected from electronic medical records of elderly patients with TKA in each hospital in 2015.Extracting contents including:(1)general condition of patients: age,gender,basic diseases;(2)serum protein indexes: serum total protein(TP),albumin(ALB),prealbumin(PA),retinol binding protein(RBP);(3)other nutritional indexes: total lymphocyte count(TLC),body mass index(BMI),hemoglobin(HB);(4)operation information: the first surgeon levels,operation mode,tourniquet pressure,operation time.1.2 Statistical analysisThe relative risk(RR),the rate difference(RD),and the attributable risk percentage(ARP)related to the incidence of PWH were calculated with the corresponding criteria mainly for those serum albumin indexes,HB,TLC and BMI;univariate analysis and multiple logistic regression analysis were used to calculate the influencing factors and independent risk or protective factors related to PWH.2.Intervention study of whey protein on postoperative wound healing in elderly TKA patients2.1 Randomization and interventionThe elderly TKA patients were randomly divided into control group and experimental group,according to the random numbers generated by software SPSS.The control group was given standardized diet education daily,while on the basis of routine diet,the experimental group was given the additional supplement of whey protein(0.5g/kg·d).2.2 Observational indexesMain index: the incidence of PWH in 30 days after surgery;Other indexes included :(1)serum protein indexes before surgery and at day 1,3,5 after surgery: TP,ALB,PA,RBP,and TLC;(2)inflammatory markers like erythrocyte sedimentation rata(ESR),c-reactive protein(CRP),tumor necrosis factor alpha(TNF-?),and postoperative nutritional indexes at day 1,3,5 after surgery,inflammatory markers at day 3,5 after surgery;(3)range of motion(ROM)and pain score at day 3,5,30 after surgery.Results:1.Retrospective study on the effects of serum protein levels to postoperative wound healing in elderly patients with TKA1.1 The study collected related information from 1236 elderly TKA patients throu gh 7 research units,according to the established exclusion criteria,234 cases were excluded,and finally included 1002 cases.The average age of the researching objects was 68.98±5.84 years old,and there were 812 females(81.04%)and 190 males(19.96%).1.2 All the relative risk(RR)of poor wound healing in groups with nutritional indicators lower than the normal,were calculated out >1;RR values of the PA at the first time after admission,ALB,TLC at day 1 and PA at day 3-5 after surgery were >2;RR values of PA at day 1 after surgery were 3.71 and ALB at the first time after admission were 4.27.1.3 Univariate analysis showed that there were significant differences between two groups of PWH and normal wound healing(NWH)in preoperative indexes including,TP,ALB,PA,HB,BMI,postoperative indexes which including TP,ALB,PA,HB at day 1 after surgery,ALB,PA at day 3-5 after surgery(P<0.05).1.4 Using variable selection stepwise regression method,the results of multiple logistic regression showed PA at day 1 and TLC at day 3-5 after surgery were in the final regression equation,they were independent protective factors for PWH(P<0.05).In addition,multivariate analysis also showed that tourniquet pressure was an independent risk factor for PWH in elderly TKA patients(P<0.05).2.Intervention study of whey protein on postoperative wound healing in elderly TKA patients2.1 Between the experimental group and the control group,the difference in postoperative incidence of PWH in 30 days was statistically significant(P<0.05).Comparison of two groups' difference in nutritional indexes showed that RBP at day 1,TP,ALB,RBP at day 3,ALB,PA,RBP at day 5 after surgery were statistically significant(P<0.05).2.2 There was significant difference between the two groups in TNF-? at day 5 after surgery(P<0.05).In addition,the ROM at day 5 after surgery also showed statistical difference(P<0.05).2.3 Compared with the control group,the total cost of hospitalization in the experimental group was reduced by 6.95%,the cost of incision treatment was reduced by 77.28%,and the hospitalization time was reduced by 1.05%.Conclusions:1.When perioperative total protein,albumin,prealbumin,retinol binding pr otein and total lymphocyte count were lower than normal levels,which can lead to higher rates of poor wound healing.The corresponding RR values of ALB at the first time after admission and PA at day 1 after surgery were the the highest,which was worthy of especial attention.2.The PWH in elderly TKA patients may be associated with some serum protein indexes which include ALB,PA preoperatively,TP,ALB and PA at day 1 postoperatively,ALB and PA at day 3-5 postoperatively.3.PA at day 1 and TLC at day 3-5 after surgery were independent protective factorsfor PWH in elderly TKA patients,and tourniquet pressure was an independent risk factor.The level of these two protective factors should be actively promoted,and attention shouldbe paid to the scientific regulation of tourniquet pressure in TKA operation.4.In the nutritional intervention study,the use of whey protein preparation duringperioperative period for elderly TKA patients can effectively raise serum protein level andreduce the incidence of postoperative PWH.5.The use of whey protein preparation during perioperative period for elderly TKApatients can not only improve ROM at day 5 after surgery,but also lower the cost ofhospitalization,wound treatment,and reduce the hospitalization ti me.