Static Venous Pressure Measurement by Access Alert in Detecting Vascular Access Stenosis

Jung, Hyun Wha; Kim, Young Ok; Song, Woo Jung; Kim, Young Soo; Yoon, Sun Ae; Kim, Byung Soo; Song, Ho Cheol; Kim, Suk Young; Choi, Euy Jin; Chang, Yoon Sik; Bang, Byung Kee

Abstract

BACKGOUND: K/DOQI guideline recommends measurement of vascular access blood flow and static intra-access pressure (SIAP) as important vascular access monitoring methods. Vascular access blood flow is measured by ultrasongraphic dilution method or Doppler sonographic examination. But these two examinations are expensive and the former needs special apparatus and the latter has the limitation of inter- and intra-observer variability. This study was performed to evaluate the utility of SIAP measured by Access Alert in detecting vascular access monitoring in hemodialysis (HD) patients.
METHODS
Ninety-two patients on chronic HD via arteriovenous fistulas (AVF) and grafts (AVG) were included in this study. Mean age was 5513 and the number of man was 34. Sixteen patients had AVG. We measured both dialysis venous pressure (DVP) and SIAP. SIAP was measured by Access Alert (Medisystems, Seattle, WA) via arterial and venous canulation into vascular access and then static intra-access pressure ratio (SIAPR) was calculated by SIAP/MAP (mean arterial pressure. Venography was performed to find venous stenosis in patients who had abnormal levels of SIAPR.
RESULTS
Arterial and venous SIAPRs in patients with AVG were higher than those in patients with AVF, respectively (arterial line:0.69+/-0.24 vs. 0.29+/-0.18, pp<0.001, venous line:0.60+/-0.23 vs. 0.23+/-0.16, p<;0.001). Of the total 92 patients, 30 patients had abnormal SIAPR. We performed venography in 19 out of these 30 patients. Of the 19 patients, 17 patients had stenotic venous lesions in which 14 patients had severe stenotic lesions and required radiologic intervention. In 14 patients with severe stenotic lesions, only 2 patients showed abnormal DVP and other patients showed normal DVP.
CONCLUSION
The measurement of static intra-access pressure by Access Alert is simple and effective in detecting vascular access stenosis.