The Comparison of Access Alert and Drip Chamber Methods in Measuring Static Venous Pressure in Hemodialysis Patients

Lee, Jae Pil; Kim, Young Ok; Song, Woo Jung; Song, Ho Cheol; Kim, Young Soo; Yoon, Sun Ae; Kim, Yong Soo; Kim, Soo Young; Choi, Euy Jin; Chang, Yoon Sik; Bang, Byung Kee

Abstract

BACKGOUND: Static venous pressure (SVP) by Access Alert method has been known to be more strongly predictive of venous stenosis than dialysis venous pressure (DVP). This study was performed to compare Access Alert and drip chamber methods in measuring static intra-access pressure in hemodialysis patients.
METHODS
Eighty-one patients on chronic hemodialysis via arteriovenous fistulas (AVF) or grafts (AVG) were included in this study. We measured SVP using both drip chamber and Access Alert methods. In drip chamber method, we measured venous drip chamber pressure (P(DC)) and the height from the venous needle to the top of the blood in the venous drip chamber (delta H). The pressure difference (delta P(H)) was estimated as delta H (cm) x 0.76 and SVP in AVF (PAVF) was calculated as sum of PDC and delta P(H). In Access Alert method, we measured SVP directly through venous cannulation of vascular access. Finally static intra-access pressure ratio (SIAPR) was calculated by SVP divided mean arterial pressure (MAP).
RESULTS
Mean SVP measured by Access Alert and drip chamber methods were 0.28+/-0.21 (0.08-0.96) and 0.35+/-0.18 (0.13-0.92), respectively. Mean SIAPR by Access Alert method well correlated with mean SIAPR by drip chamber method (r=0.885, p< 0.001).
CONCLUSION
This study suggests that Access alert method correlates highly with drip chamber method in measuring SVP and it can be useful method in detecting vascular access monitoring.