Haemodynamic effects of food intake during haemodialysis

Background: There is some doubt whether food intake during haemodialysis (HD) is detrimental to haemodynamic stability. Methods: We studied 20 stable non-diabetic HD patients during a single session. A standard meal was given 45 min into dialysis. Relative blood volume (RBV), cardiac output (CO), systemic vascular resistance (SVR) and extracellular fluid (ECF) resistance were monitored continuously. Total protein and albumin were measured. Results: There was a significant reduction in RBV after food ingestion (maximum reduction 3.4 ± 1.1%; p < 0.001). There was no significant change in ECF resistance, heart rate, CO or SVR. Mean arterial pressure was significantly different from pre-food levels 30 min after food (p = 0.04). The rate of change of total protein and albumin concentration was significantly higher immediately after food ingestion. Conclusions: Food intake during HD caused significant reductions in RBV, possibly related to fluid shifts from intestinal microcirculation to interstitium. CO and SVR remained stable perhaps because of the opposing effects of food ingestion and UF.