Assessment of dry weight in haemodialysis patients by the volume markers ANP and cGMP.

The concept of dry weight of a dialysis patient is generally accepted and usually defined as the body weight less than which a normalbuminaemic patient maintained on haemodialysis will become hypotensive with fluid removal, and above which the same patient will be hypertensive and show subtle signs of fluid expansion. This concept is crucial to control hypertension adequately and to avoid risks of intradialytic hypotension. The exact determination of post-dialysis dry weight by clinical acumen is an exercise that often taxes the clinical judgement of even the most astute nephrologist. In certain diseased states associated with end-stage renal failure, clinical evaluation is unreliable in assessing dry weight. In fact, 25-50% of patients on chronic haemodialysis have an incorrectly determined dry weight [1,2]. The morbidity of dialysis therapy may be increased in each instance. With the increased number of both elderly multimorbid patients and patients with primary heart disease entering the chronic dialysis programme, exact estimation of dry weight seems to be of even more clinical importance.