Long nocturnal dialysis

The continuous growth of the dialysis pool in our unit induced us to organize a third long nocturnal dialysis (LND) session, considering the excellent survival and rehabilitation results reported with this method. This paper analyzes the results and assesses the role of LND among the different dialytic treatment options.

Out of 18 patients on LND, 13 (12 males and 1 female, mean age 52 +/- 13 years, time on dialysis 21.8 +/- 23.8 months) with >6 months' experience were studied, and 9 underwent a further metabolic evaluation. LND was performed using 1- to 1.4-m(2) Hemophan membranes, bicarbonate buffer, 200-250 ml/min blood flow, and 300-500 ml/min dialysate flow, 8 h three times a week. Kt/V and protein catabolic rate (3-point classic urea kinetics), postdialytic weight, serum albumin, total protein, hemoglobin, Ca(2+), phosphate, intact parathyroid hormone, bioimpedance body water, blood pressure, and drug use (antihypertensives, phosphate binders, erythropoietin, vitamin D, hypnotics) were evaluated in each patient during hemodialysis and LND. In the metabolic study (done twice), sodium (compared with the Kimura model), potassium, phosphate, and urea were analyzed in blood and inlet and outlet dialysate after 0, 2, 4, 6, and 8 h.

The mortality was low (1 death every 247 patient-months). After 19 +/- 8.1 months of LND, the postdialytic weight rose from 68.5 +/- 9.6 to 70.8 +/- 10.7 kg (p < or = 0.01), and the hemoglobin concentration rose from 10.8 +/- 2.2 to 11.8 +/- 1.8 g/dl (p < or = 0.05); phosphate dropped from 5.6 +/- 2.0 to 4.4 +/- 1.3 mg/ dl (p < or = 0.01) and the systolic blood pressure from 152 +/- 15 to 143 +/- 19 mm Hg (p < or = 0.05). In the metabolic study, the sodium profile was significantly lower during the last 4 h than in the Kimura model. The potassium concentration, stable between 4 and 6 h, rose against the gradient during the last 2-hour period. The behavior of sodium and potassium during the last part of the dialysis session can be taken to indicate exhaustion of the sodium/potassium pump. Phosphate showed a gradual reduction with no intradialytic and only a moderate postdialytic rebound. The postdialytic urea rebound was 23.4%.

LND is a useful additional tool for nephrologists in treating chronic renal failure, it is easy to organize, and it shows overall good results. Together with other dialysis methods, this schedule permits individualized treatment for each uremic patient.