Figure 1 Changes in relative plasma volume (RPV) in response to reductions in dry weight in a patient on dialysis Figure 1 | Changes in relative plasma volume (RPV) in response to reductions in dry weight in a patient on dialysis. Despite the use of four antihypertensive medications, the patient's mean interdialytic ambulatory blood pressure at baseline was 149/89 mmHg. RPV monitoring at baseline revealed no change in intravascular blood volume during dialysis (flat slope), indicating extracellular volume expansion. After 8 weeks of dry-weight probing, a 2.0 kg reduction in postdialysis weight was observed; RPV monitoring at 8 weeks revealed a 3.15% decrease in RPV per hour during dialysis. Mean 44 h ambulatory blood pressure was reduced by 24/12 mmHg at this time point. Permission obtained from the American Society of Nephrology © Agarwal, R. & Weir, M. Dry-weight: a concept revisited in an effort to avoid medication-directed approaches for blood pressure control in haemodialysis patients. Clin. J. Am. Soc. Nephrol. 5, 1255–1260 (2010). Permission obtained from the American Society of Nephrology © Agarwal, R. & Weir, M. Dry-weight: a concept revisited in an effort to avoid medication-directed approaches for blood pressure control in haemodialysis patients. Clin. J. Am. Soc. Nephrol. 5, 1255–1260 (2010). Georgianos, P. I. & Agarwal, R. (2016) Epidemiology, diagnosis and management of hypertension among patients on chronic dialysis Nat. Rev. Nephrol. doi:10.1038/nrneph.2016.129