Renal replacement therapy : dialysis
Two types of renal replacement therapy are available for the treatment of AKI. They are intermittent (IHD) therapy and continuous renal replacement therapy (CRRT).
Hemodialysis
Hemodialysis roughly translates as “separating from the blood.” Indications and contraindications for hemodialysis are listed in Box 31-4. As a treatment, Hemodialysis
Separates and removes from the blood the excess electrolytes, fluids, and toxins by mean of a hemodialyzer. Although hemodialysis is efficient in removing solutes, it does not remove all metabolites. Levels of electrolytes, toxin, and fluids increase between treatments, necessitating hemodialysis on a regular basis. Hemodialysis therapy is always intermittent; each dialysis treatment takes 3 to 4 hours. In the acute phase of kidney failure, dialysis is performed daily. The dialysis frequency gradually decreases to three times per week as the patient moves into a more chronic phase of kidney failure.
Hemodialyzer. Hemodialysis works by circulating blood outside the body through synthetic tubing to a dialyzer is sometimes described as an artificial kidney. While the blood flows through the membranes, which are semipermeable, fluid bathes the membranes and, through osmosis and diffusion, performs exchanges of fluid, electrolytes, and toxins from the blood to the bath, where toxins and dialysate then pass out of the artificial kidney. The blood and the dialysate bath are shunted in opposite directions through the dialyzer to match the osmotic and chemical gradients at the most efficient level for effective dialysis.