title: The StenTec gauge for measuring static intra-access pressure ratio (P(Ia Ratio) ) of fistulas and grafts.
abstract: The StenTec™ Gauge provides a method to determine the static intra-access pressure ratio (P(Ia Ratio) ) within a fistula or graft. The StenTec Gauge estimates the peak systolic pressure within the fistula or graft by measurement of the distance that the blood-air interface progresses into the tubing of the fistula needle, after the needle is inserted "dry" into the fistula or graft and before the cap is removed from the tubing. The peak systolic pressure is graphically compared with the systolic arterial blood pressure of the patient, to determine P(Ia Ratio) . For best accuracy, the StenTec Gauge should be chosen that best matches the internal volume of the fistula needle tubing (2.3-2.6 ml for 12-inch tubing and 3.6 ml for 16-inch tubing) and the approximate elevation of the city in which it is used (0-1000, 1000-3000, and 3000-6000 feet above sea level). In this article, we explain the rationale for this method of surveillance, evidence for accuracy of the StenTec Gauge, and the correlation of changes in the P(Ia Ratio) to the development of stenosis in a fistula or graft.
authors.affiliation: HemoCleanse, Inc. and Indiana University Health Arnett, Lafayette, Indiana 47904, USA. sash@hemocleanse.com
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Ash
authors.forename: Rajiv
authors.initials: R
authors.lastname: Dhamija
authors.forename: Mohamad Y
authors.initials: MY
authors.lastname: Zaroura
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Hentschel
mesh_terms: D001166:Arteriovenous Shunt, Surgical; D001794:Blood Pressure; D006083:Graft Occlusion, Vascular / Q000175:diagnosis; D006801:Humans; D055641:Mathematical Concepts; D006435:Renal Dialysis / Q000295:instrumentation*