Nutritional management of patients with endstage renal disease is a challenging exercise for nephrologists, nutritionists and dialysis nurses, with a high unmet need for improving caloric and protein requirements, whilst balancing the inevitable increase in sodium, potassium and phosphorus intakes which accompanies nutrition supplementation.¹ While it is common for nephrologists to prescribe protein supplements, compliance to these at prescribed doses is relatively low. Many dialysis patients in India are still unable to meet the high protein requirement and therefore, suffer from protein-energy wasting. In the light of the recent studies on feeding during hemodialysis which encourage intradialytic meal intake, and also an observation of regular intradialytic eating in several of our patients on hemodialysis, we designed this study to determine the optimal timing of oral nutrition supplementation.^2.3 Hemodialysis is a catabolic state with substantial protein losses, depending on the technique and membrane parameters. Therefore, provision of directly observed high protein meal during hemodialysis or before it, can be beneficial in mitigating the muscle-wasting induced by hemodialysis.

Brief review:

A point of contention is the timing of oral nutrition supplements. Few studies done previously, have highlighted higher incidence of hypotensive episodes in those patients eating during hemodialysis, which is explained by splanchnic vasodilatation and fall in systemic vascular resistance.^4,5 However, the effect of eating on hemodynamics during hemodialysis is inconsistent. The present study will also evaluate frequency of hypotensive episodes and the general tolerability of the hemodialysis when the patient has eaten. Another cause for concern is the observation of decreased dialysis efficacy as measured by Kt/V when intradialytic oral nutrition is provided.^6,7 The fall in Kt/V in these studies is minimal and unlikely to cause clinical effects. Also, it is unclear from previous studies, whether urea is the only solute whose removal is affected by eating a high protein meal during dialysis, or does the effect extend to potassium and phosphorus removal as well. The present study will measure changes in serum levels of urea, potassium and phosphorus and also directly assess dialysate removal of these nutrients. By measuring dialysate removal of solutes, it can determine the safety of eating during hemodialysis, for patients with higher baseline urea, potassium and phosphorus.

Allowing for eating during hemodialysis is a policy matter which varies from unit to unit, and previous surveys conducted in the United States revealed that a substantial proportion of nephrologists support intradialytic eating.⁸ Certain practical aspects govern our institute’s policy for allowing eating during dialysis. First, many patients come from far-flung areas and may not find the time to prepare and consume a meal prior to coming for a dialysis session. Second, patients commonly report hunger after starting dialysis which can be mitigated by eating during dialysis. Ensuring consumption of a high calorie and high protein meal in a directly observed manner has previously shown improvement in nutritional parameters. ⁹