Because continuous renal replacement
therapy (CRRT) may enhance inflammatory mediator removal, this review
assesses its impact on multiple organ failure (MOF). Regarding MOF with
acute renal failure (ARF), the overall mortality of 2313 CRRT patients
(43 studies) was 62.8% compared with 59.1% (p = 0.046) in 961 intermittent hemodialysis (IHD) patients (12 other
studies). Of 13 CRRT studies with an IHD comparison group, 3 showed
that the groups had a similar risk, but IHD mortality was higher; 1
noted that CRRT had lower mortality (risk not stated); and 4 showed
similar mortality and greater CRRT risk. Aggregate mortality was IHD
69.5% and CRRT 63.9% (p = 0.02). Of the six studies
with matched groups (age and APACHE II scores), IHD mortality was
higher (70.9% vs. 60.1%, p = 0.01). CRRT pulmonary
gas exchange, hemodynamic instability, azotemia control, fluid
overload, and nutritional support were better. Regarding MOF without
ARF, of 14 CRRT studies (14.5 patients per study), only 4 had
comparison groups. Patient conditions were as follows: acute
respiratory distress syndrome, six studies; sepsis, three studies;
septic shock, two studies; pancreatitis, one study; critically ill
patients, one study; and cardiac surgery with respiratory failure, one
study. Of the three studies with a control group, the mortality was the
same. There was minimal evidence that CRRT improved pulmonary gas
exchange or hemodynamic instability. For MOF patients with ARF, there
is compelling evidence that CRRT provides better survival than IHD and
more improvement in pulmonary gas exchange, hemodynamic instability,
azotemia control, fluid overload, and nutritional support. In patients
with MOF and no renal failure, there is little evidence that CRRT
enhances survival, oxygenation, or perfusion. Controlled trials
demonstrating a CRRT benefit are necessary before CRRT can be
recommended for MOF without ARF.