2019 Volume 46 Issue 2 Pages 133-140
Vascular access (VA) is essential for hemodialysis patients. The first VA produced at dialysis introduction, in particular, is the most important. Therefore, sufficient evaluation before VA production is necessary, and ultrasonic inspection is an effective method for that purpose. In the preoperative evaluation, observation by inspection and palpation is performed before ultrasonic examination. Evaluation by ultrasonic examination: The artery is measured for the presence or absence of stenosis and occlusion, and the inner diameter of the blood vessel and its patency are evaluated. The degree of calcification should also be observed. It is reported that VA is feasible if the arteriovenous diameter is 1.5 to 2.0 mm or more. For the vein, the entire vessel course and its continuity, vessel inner diameter, presence or absence of stenosis, position of a venous valve, and the like are observed. The anastomotic vein diameter is preferably 2.0 mm or more under avascularization. In addition, as with palpation, a search is made for a puncturable site. If the depth of the vessel is 5 mm or more, it becomes difficult to palpate and the difficulty level of the puncture increases, so we also observe the depth of the blood vessel at the expected puncture site. Conclusion: The final production site is judged comprehensively, taking into account factors other than vessel diameter such as age, puncture site, arteriovenous distance, and so on. Therefore, it is necessary to sufficiently discuss the results of the ultrasonic examination and the patient background with the operator for determination of the production site. If possible, it is desirable for the examiner and the operator to work together.
