Intensity of CRRT in the ICU, Does it Matter?

CRRT, or continuous renal replacement therapy (CVVHD/F continuous venovenous hemodialysis / hemodiafiltration) has been a great advance in the field of Nephrology. CRRT allows for a slow steady continuous form of dialysis that is much easier for a critically ill ICU patient to tolerate. Unlike conventional hemodialysis, CRRT is less taxing hemodynamically allowing use in the critically ill patients suffering with acute kidney injury and shock. Although CRRT (despite the issues with clotting) has many benefits, some of these benefits are theoretic and have not translated into an evidence based reality.

The NEJM this week reports on another somewhat disappointing study for CRRT enthusiasts (such as myself). This was a multicenter, randomized comparing two different intensities of CRRT and evaluating the 90 day mortality of both groups. Although we would have hoped that more aggressive and intensive CRRT would yield a better outcome... alas, it did not. The higher intensity CRRT prescription resulted in a lot more hypophosphatemia, but there was no reduction on the mortality rate.