Study On The Correlation Between The Ultrasound Examination Index And The Maturation Of Arteriovenous Fistula Before And 1 Day After Operation

BackgroundVascular access(VA)is an important prerequisite and guarantee for the successful completion of hemodialysis(HD).Arteriovenous fistula(AVF)is the preferred vascular access for hemodialysis,among them the radio-cephalic arteriovenous fistula(RC-AVF)is the most common.However,about 20%-60%of arteriovenous fistulas may be failed to early maturation.The study found that routine ultrasound examination on fistula can improve AVF maturity and patency.Previous studies have reported that vein diameter is an independent risk factor for predicting the maturation of arteriovenous fistulas.Veins with a diameter of less than 1.6-2.5mm are often associated with the failure of arteriovenous fistula maturation.The veins are highly compliant,and the use of tourniquets can better understand the dilatability of the patients’ veins.At present,there is no consensus on the research of the optimal vein diameter and vein dilatation for the construction of AVF.After the fistula is established,early evaluation of the maturity of the fistula can promptly formulate different programs according to the patient’s own condition to promote the maturation of the fistula.The brachial artery has less turbulent flow and stable blood flow than the anastomoses of the fistula.It is easy to image under color doppler ultrasound,and there may be hematoma or ederna interference in the surgical site early after the fistula.Therefore,the brachial artery can be examined early by ultrasound to assess the function of the internal fistula.At present,few studies have focused on the correlation between the doppler blood flow spectrum of the brachial artery and the early maturation of the fistula after 1 day of postoperative ultrasound.ObjectiveThis study mainly used ultrasound to evaluate the diameter and dilatation of the cephalic vein before and after the application of tourniquet,and observed the blood flow spectrum of the brachial artery before and after the first day of AVF,analyzed the relationship between the above ultrasound measurement indexes and the maturation of the fistula,and determined the size of the best cut-off value of the related variables that affect the maturation of the fistula.MethodsIn this study,91 patients with RC-AVF were selected for the first time from December 2017 to November 2018 in a blood purification center of a hospital in Henan.Ultrasound examination:In a room at a temperature of 24-26℃ the same physician used ultrasound to measure the inner diameter of the anterior and posterior with the tourniquet of the cephalic vein and forearm of the planned surgical site,venous dilatation was expressed by the difference between the posterior cephalic vein with the tourniquet and the anterior cephalic vein,and measured the peak systolic velocity of the brachial artery and the blood flow volume of the brachial artery at 2 time points before and 1 day after the operation at the two centimeters of the proximal branch of the radial artery and ulnar artery,repeated all measurements for 3 times and taked the average.Surgical protocol:All the operations were performed by the same doctor in the blood purification center,and local infiltration anesthesia was selected,and 7-0 vascular suture was used for continuous anastomosis of the cephalic vein and radial artery.Fistula maturation and follow-up:The patients were followed up 6 weeks after surgery to evaluate their fistula function.According to the maturity of the fistula,they were divided into 70 cases of mature fistula and 21 cases of immature fistula.Results1.There was no statistically significant difference between the mature group and the immature group in terms of age,sex ratio,etiology of chronic renal failure(diabetic nephropathy/non-diabetic nephropathy)and the history of central venous catheterization(P>0.05).2.Compared with the immature group,the diameter of the anterior and posterior with the tourniquet of the cephalic veins and dilatation of the cephalic vein in the mature group were statistically significant(P<0.05);the PSV of preoperative brachial artery and brachial artery flow volume in the mature group were compared with the immature group,the difference was not statistically significant(P>0.05);the brachial artery PSV on the first postoperative day and the brachial artery flow volume on the first postoperative day in the mature group were greater than those in the immature group,and the difference was statistically significant(P<0.001).3.Taked the AVF maturation as the dependent variable,the diameter of the anterior and posterior with the tourniquet of the cephalic veins,the dilatation of the cephalic vein,the brachial artery PSV on the first postoperative day,and the brachial artery flow volume on the first postoperative day were the independent variables.Logistic regression analysis showed that the diameter posterior with the tourniquet of the cephalic vein,the dilatation of the cephalic vein,and the brachial artery flow volume on the first postoperative day were independent risk factors for predicting the maturation of arteriovenous fistula(P<0.05).4.Analyzed the ROC curve of independent risk factors for mature fistula to evaluate its clinical diagnostic value.The results were as follows:the area under the ROC curve of the diameter posterior with the tourniquet of the cephalic vein was 0.837(P<0.001),and its cut-off value was 2.4mm;the area under the ROC curve of the dilatation of the cephalic vein was 0.894(P<0.001),whose cut-off value was 0.4mm;The area under the ROC curve of brachial artery flow volume on the first postoperative day was 0.832(P<0.001),and its cut-off value was 249.29 mL/min,the differences were statistically significant.Conclusions1.The diameter posterior with the tourniquet of the cephalic vein and the dilatation of the cephalic vein are independent risk factors for the maturation of the arteriovenous fistula.The diameter posterior with the tourniquet of the cephalic vein>2.4 mm,the dilatation of the cephalic vein>0.4 mm are exact cuf-off points,which best predict maturation of the fistula.2.The brachial artery flow volume on the first postoperative day is related to the maturation of the arteriovenous fistula.249.29mL/min can be used as the critical point for predicting the maturation of the fistula on the first postoperative day.