NJCC_01 bwerk v1.indd

Introduction The kidney maintains blood pH by filtering metabolic acids and regenerating blood buffers such as bicarbonate. During CRRT, pH is regulated in a comparable way, metabolic acids are filtered or dialysed and buffer is replaced to correct metabolic acidosis and compensate for the bicarbonate lost by filtration or diffusion. Lactate, bicarbonate, acetate and citrate are the available buffers. Acetate is no longer generally used because of its lower buffer capacity, vasodilatory and negative inotropic effects [1]. Citrate is a potent buffer which is given in the setting of regional anticoagulation; its use has previously been extensively discussed [2]. When conventional anticoagulation is used, in daily practice the choice of buffer is either lactate or bicarbonate. The lactate or bicarbonate content of commercial replacement fluids ranges from 32-46 mmol/l.