INADEQUACY OF DIALYSIS

HOW TO FIGHT INADEQUACY OF DIALYSIS, INCREASED BLOOD FLOW OR INCREASED DIASYLATE FLOW?

Abstract

Background: Objectives: In patients with end stage renal disease, inadequate
dialysis can lead to increased morbidity and mortality. We conducted a study to analyze effects
of increasing dialysate flow rate (DFR) and blood flow rate (BFR) on adequacy of dialysis.
URR was used as an indicator of dialysis adequacy. Study Design: Prospective comparative
study. Period: 02 months (February 2017 to March 2017). Setting: Department of Nephrology,
Lahore General Hospital. Method: 40 patients on maintenance hemodialysis were included.
We divided study in three phases. First phase with blood flow 300mL/min dialysate flow 500mL/
min. Second phase blood flow 350mL/min dialysate flow 500mL/min. Third phase blood flow
300mL/min dialysate flow rate 800mL/min. Blood samples were collected before and after each
dialysis session. Urea reduction ratio (URR) was used to measure delivered dose of dialysis and
was assessed at the two levels of dialysate flow rate and two blood flow rates. Statistical analysis
was done by using SPSS 23.0 software package. P values <0.05 was taken as statistically
significant. Result: After statistical analysis we reached the conclusion that enhancing blood
flow rate from 300 to 350 is associated with an increase of URR of 6.9 % as compared to
increasing dialysate flow rate from 500 to 800 of 4.6%. In both settings increase in URR was
clinically significant. We can also deduce that increase in dialysate flow will allow us to achieve
a substantial increase in dialysis dose as assessed by urea reduction ratio for a given amount
of dialysis time when we are unable to achieve a high blood flow rate. Difference in increase
in URR for two groups one with increased blood flow and other with increased dialysate flow
was statistically insignificant (p value >0.05). Conclusion: Our study shows that if we increase
blood flow rate to 350 mL/min from 300 mL/min and dialysate flow rate to 800 mL/min from usual
500 mL/min there is significant increase in URR and adequacy of dialysis. We can decrease
mortality and morbidity by increasing adequacy to optimal level using both methods according
to patient feasibility and clinical status.