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José Guiserix, Service de Néphrologie-Dialyse, BP 350 CHSPT, F-97448 Saint-Pierre, La Réunion (France) Dear Sir, Jensen et al. [ 1 ] have recently described a triple-pump dialysis system using a lactate-buffered dialysate. We have extensively been using such a dialysis fluid over the past 5 years, with a double-pump system, in 1,473 hemodialysis sessions in the intensive care unit (n = 585) or in the nephrology department (n = 888) for acute renal failure, as well as emergency dialysis in chronic renal failure patients. Our equipment, identical to that used by Tam et al. [2], consists of a BSM-22 blood module (Hospal) coupled to a venous pressure module (VPM; Hospal), used under bio-filtration mode. The blood flows at 250 ml/ min, and is connected to a double-lumen central catheter or to two single-lumen femoral catheters. Dialysate flow is controlled by the other pump, and circulates countercur-rently through a standard blood tubing set whose pump segment is located upstream of the dialyzer, its internal diameter allowing for a maximum flow of 5 liters/h. A standard extension peritoneal dialysis connecting device enables a linkage between the 5-liter peritoneal fluid bag and the dialysate tubing set inlet side. We initially chose a regenerated cellulosic hollow-fiber dialyzer, then switched to cellulose diacetate which is more biocompatible [3], the surface being 1 m2 and the ultrafiltration coefficient 4.8 ml/ min/mm Hg (Ambio-50wet; Asahi Medical). Performances are sufficient for a low dialysate flow, urea clearance being close to the dialysate rate flow, priming volume is small (59 ml), the low permeability avoids excessive loss of amino acids seen with high-flux membranes [4]; it is also inexpensive. The low coefficient rate limits the spontaneous ultrafiltration rate at a fixed 800 ml/h. The dialyzer outgoing fluid is collected in a graduated container allowing a volume determination at each bag change. When < 800 ml/h has to be lost by the patient, a compensation is regularly made up using a prediluting 200-ml isotonic serum NaCl (0.9%) flush, or iso-tonic sodium bicarbonate (1.4%) which in addition buffers dialysate acidity (pH = 5.5) [5]. Forced convection improves the efficiency of dialysis, and compensation allows for flushing the circuit to prevent and detect partial clotting, especially when the usual initial single 3075 Axa calcic nadroparin injection is contraindicated. The 5-liter intermittent peritoneal dialysis solution bag (Dienal 1.36% glucose; Baxter) is set, before and during utilization, on standard continuous ambulatory peritoneal dialysis bag heaters (bw03; Baxter). The dialysate volume used for each session was usually 30 liters, convection being 4 liters, the total hemodiafiltration volume is close to the total body water, and to the urea volume distribution, of a 70-kg patient. Each session was managed by a specifically assigned hemodialysis nurse. This ‘low-flow venovenous intermittent hemodiafiltration’ may, if necessary, be performed daily or can use larger dialysate