A Clinical Significancy of Evoked Thrill Test in the Arteriovenous Fistula

PURPOSE: Arteriovenous fistula at the wrist has remained the procedure of choice for long-term chronic hemod ialysis since its development by Brecia and Cimino in 1966. Thrombosis is the most common cause of early failure after arteriovenous fistula procedure, should be reconized preoperatively or intraoperatively, but no consensus exits regarding the ideal preoperative or intraoperative screening method for access surgery. We describe a simple intraoperative maneuver that can be used to detect proximal stenotic vein segments. METHODS: From September 1998 to September 1999, a total of 117 arteriovenous fistulas were performed for permanent hemodialysis in patients with chronic renal failure. Of them, a intraoperative evoked thrill test was performed in 61 patients (A group), in 56 patients (B group or control group) was not. RESULTS: Early failure rate (<30 days) was 12.5% in A group, 9.8% in B group or control group. In this study, the specificity and positive predictive value of the evoked thrill test was 100%, indicating that this maneuver is highly accurate in predicting early failure. CONCLUSION: Evoked thrill test is a simple and useful intraoperative method for improving the patency rate of autologous arteroiovenous fistula.

The Effect of the Cyclosporine in the Renal Ischemic and Reperfusion Injury / 대한이식학회지

During renal ischemia, ATP is degraded to hypoxanthine and xanthine oxidase is accumulated. When reperfusion develops, large amount of oxygen is supplied and superoxide radicals are generated. Free radical species were generated by a series of oxygen mediated reaction resulted in lipid peroxidation in the cellular membrane, which causes renal injury. Cyclosporin (CsA) is a potent immunosuppresant. however, one of the main adverse effects of CsA is nephrotoxicity. The mechanism of nephrotoxicity is still not fully understood. Only we proposed it as being responsible for the derangement of renal function, enhanced free radical species, vasoconstriction, ATP depletion, several vasoactive mediators. Based on the previously studied data with experimental animals, we studied a relationship between ischemia and reperfusion renal injury and cyclosporine with experimental rats. Four groups of Sprague-Dawley rats were studied: 1) a control group, only 60 minnites clamping and on day 3 is sacrified, 2) second control group, 60 minnites clamping and on day 5 is sacrified, 3) in the third and fourth group, after 60 minnites clamping, cyclosporine, 20 mg/kg/day was administrated intraperitoneally and were sacrified on day 3 and day 5, respectively. Antioxidant enzymes (SOD, Catalase), TBA-RS, GGT were measured by a specific biochemical method, and results were analyzed according to Wilcoxon rank sum test. p-value <0.05 was considered statistically significant. In cyclosporin administrated rats, GGT was elevated significantly on day 3 and day 5 (p=0.0367, p=0.0216), but SOD, Catalase, TBA-RS were not identified a significant change. In conclusion, on renal ischemia and reperfusion,cyclosporin induced renal injury is not related to free radical species, which suggests that other unknown mechanisms influence renal injury.