HEMO equilibrated Kt/V goals are difficult to achieve in large male patients

The long-term outcome of chronic hemodialysis patients is influenced by the adequacy of dialysis treatment. A major objective of the ongoing US HEMO Study is to determine if a higher target value of treatment as measured by the equilibrated Kt/V (eKt/V), a calculation of dialysis adequacy developed for the study, of 1.45 results in a better outcome than the presently accepted target value for eKt/V of 1.05 (approximately equal to spKt/V of 1.2). eKt/V corrects for urea rebound and gives a better estimate of actual treatment received. To examine the feasibility of achieving the higher eKt/V in large hemodialysis patients, a retrospective analysis of 389 monthly eKt/V values from 65 men on chronic hemodialysis of larger than average size dialyzed at high blood and dialysate flows (QB 400, QD 800 ml/min) with large dialyzers (1.8-2.2 m2) for longer than 4 hours three times weekly was performed. A total of 278 treatments considered optimal by a blood water urea clearance estimate were included in the final analyses. The mean body weight and Chertow water volume were 84.3+/-16.5 kgm and 50.0+/-6.7 L, respectively. The mean sp Kt/V was 1.29+/-0.17. The mean eKt/V was 1.16+/-0.14 and was inversely correlated with weight and water volume (p < 0.0001). Despite the large dialyzers and high blood and dialysate flow rates, no patient weighing more than 80 kgm or with body water volume exceeding 46 liters achieved an eKt/V of 1.45. This study suggests that creative dialyses will be required to achieve the HEMO "high arm" target in large patients.