Hemodiafiltration procedures

Although hemodialysis and hemofiltration are often considered separate therapies, some clinical treatments rely on a combination of the two and therefore can be classified as hemodiafiltration procedures. Treatment techniques can be further stratified as to whether they are intermittent or continuous in nature, and whefiier the vessels accessed are both venous, or arterial and venous. Due to a lack of definitive prospective randomized trials, the relative advantage of continuous versus intermittent treatment is unsown, although continuous administration is felt to be more gentle in some circles, allowing greater time for toxin equilibration and removal (Meyer, 2000). 

RRT includes dialysis procedures such as HD, PD, continuous hemofiltration (HF), and continuous hemodiafiltration (HDF). These techniques are used to temporarily or permanently remove toxic substances from the blood when the kidneys cannot satisfactorily remove them from the circulation. In addition, kidney transplantation has also become an effective form of RRT. Extensive laboratory support is required by an RRT program (Table 45-12). 

Continuous venovenous hemodiafiltration was reported to be effective In two cases, but there is insufficient information about clearance rates to recommend this procedure. 

Drug-device interactions In a 59-year-old man with refractory status epilepticus taking topiramate, clinically important amounts of topiramate were removed by continuous venovenous hemodiafiltration for acute renal failure [302" ]. Higher doses of topiramate should therefore be used during this procedure. 

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