Analysis of factors affecting the delivered dose of hemodialysis in patients on conventional fixed dialysis regimen

Kim, Yeun Sun; Lee, Hyun Hee; Lee, Jong Ho; Kim, Eun Soo; Jin, Kyoung Soon; Kim, Jung Gon; Yoo, Seung Min; Lee, Joon Seung; Chung, Wookyung; Joo, Kwon Wook

Abstract

BACKGROUND: Although adequate removal of small solutes are essential for effective hemodialysis, many patients are suffering from inadequate delivery of hemodialysis, especially with the conventional fixed regimen of dialysis for 4 hours three times per week. We tried to evaluate actual delivered dose of hemodialysis in patients receiving 4 hours of low-flux hemodialysis, and to analyze factors affecting inadequate delivery of hemodialysis.
METHODS
97 stable maintenance hemodialysis patients who were undergoing 4 hours of hemodialysis thrice weekly were included for analysis. Prescribed dose of dialysis was calculated by Kt/V where K was in vitro urea clearance of dialyzer membrane and V was estimated according to the Watson's formula. Delivered dose of dialysis was calculated according to the Daugirdas equation. To find factors that may impair adequate delivery of hemodialysis, various clinical and technical parameters were analyzed.
RESULTS
Prescribed dose of hemodialysis was 1.37+/-0.21, while delivered dose was 1.23+/-0.27, and thus, there was a significant difference (p <0.03). In 45% of the patients, delivered dose was less than 1.2. They were heavier and prescribed dose was low. delta Kt/V (Prescribed dose-Delivered dose) was significantly greater in patients who did not use heparin therapy compared to patients who used heparin. Other parameters such as hypotension, missed treatment, sex, type of vascular access and degree of recirculation were not associated with impaired delivery of hemodialysis.