Adrenal responsiveness during and after intermittent haemodialysis.

ACTH and cortisol were measured by radioimmunoassay in 15 patients undergoing long term haemodialysis. Also a basal ACTH stimulation test was done by administration of 250 micrograms of Synachten (Synthetic ACTH, CIBA foundation) and the results compared with those of normal controls and end-stage chronic renal failure patients (CRF). All 15 had been receiving intermittent haemodialysis three times weekly for 5 hours on a twin coil dialyser. The duration of dialysis was from 6 to 20 months and the mean value of pre - dialysis serum creatinine was 1093 +/- 182 mumol/l. Both hormones had significantly risen in the middle and at the end of dialysis (p less than 0.005), While they had fallen back to normal mean levels 24 hours after dialysis. The Synachten stimulation test showed that adrenal response was within normal limits in both groups of patients, but dialysis patients responded significantly better (p less than 0.05) than patients with end stage CRF. We concluded that the adrenal responsiveness is within normal limits during and after regular haemodialysis and our likely explanation is a fall in plasma volume produced by the extracorporeal circulation and the increased turnover of cortisol during haemodialysis.