**6. References**


**14** 

*Spain* 

**Acetate Free Biofiltration with** 

R.I. Muñoz, I. Gallardo and J. Montenegro

*Hospital de Galdakao-Usansolo, Bilbao* 

**Potassium Profiled Dialysate (AFB-K)** 

Hyperkalaemia is a common, significant electrolyte disorder in uremia. Patients with chronic renal failure (CRF) undergoing haemodialysis (HD) accumulate potassium during the interdialysis period, and clearance of this potassium is one of the functions of haemodialysis. A sudden decrease in blood potassium levels during haemodialysis can induce or worsen arrhythmias, (Cupisti et al., 1999) particularly in patients already suffering arrhythmia or with risk factors for developing arrhythmia, such as heart disease of any origin, old age and diabetes mellitus, disorders which are highly prevalent in our dialysis units. Acetate Free Biofiltration with Potassium Profiled Dialysate (AFB-K) is a new haemodialysis technique that uses a potassium profiled dialysate (high at the start and low at the end of dialysis), so that by maintaining a constant potassium gradient between dialysate and blood, the decrease in blood potassium is slower – thereby contributing to

Acetate Free Biofiltration (AFB) is a haemodiafiltration technique (combining diffusion and convection) that uses a dialysate without acetate or bicarbonate, and in which postdilution sodium bicarbonate is infused (145 or 167 mmol/L) throughout dialysis (Santoro

The primary characteristic of this haemodialysis technique is the absence of acetate. It must be taken into account that in conventional bicarbonate haemodialysis we continue to use 4 mmol/L of acetate to stabilise the acid part of the dialysate. This leads serum acetate levels

The advantages of this technique comprise improved haemodynamic stability and a reduction in the number of hypotensive episodes (Cavalcanti et al., 2004), the correction of metabolic acidosis, and improved clearance versus conventional haemodialysis (Santoro et al., 2007). Haemodynamic stability is improved by avoiding acetate (related to cytokine production, vasodilation and negative inotropic action); a solution is supplied with a high sodium content in reinfusion throughout dialysis (thereby improving vascular filling) (Tsutomu et al., 2011); the temperature is lowered (through sodium bicarbonate reinfusion at room temperature); and convection is employed (this involving the use of highly-

to increase in conventional bicarbonate haemodialysis. Acetate is not used in AFB.

prevent the appearance of arrhythmia (Santoro et al., 2002).

**2. Description of the AFB technique** 

et al., 2007) (Figure 1).

**1. Introduction** 

