[Renal replacement therapy in acute renal failure]

Area of Science:

• Nephrology
• Critical Care Medicine
• Intensive Care Unit (ICU) Management

Context:

• Acute kidney injury (AKI) is a sudden decline in kidney function, frequently occurring in intensive care units (ICUs) as part of multiple organ failure (MOF).
• Incidence of AKI in ICUs ranges from 5-20%, escalating to 50% in septic shock patients, with variable mortality (20-80%).
• Lack of consistent classification systems like RIFLE and AKIN historically complicated prognosis and treatment.

Purpose:

• To review the role and optimal management of dialysis in critically ill patients with AKI and MOF.
• To evaluate the impact of early extracorporeal treatment on mortality in this patient population.
• To compare the efficacy of continuous versus intermittent dialysis modalities in heterogeneous AKI patient groups.

Summary:

• Early initiation of extracorporeal treatment can mitigate the negative impact of AKI on other organ systems, potentially reducing mortality in critically ill patients with AKI and MOF.
• All critically ill patients with AKI and MOF require dialysis dosages sufficient to counteract hypercatabolism; exceeding these levels does not improve survival in heterogeneous groups.
• Recommended dialysis targets include 20 ml/kg/h for continuous treatments and avoiding Kt/V < 4-4.5/week for intermittent hemodialysis.
• Current evidence does not favor continuous over intermittent dialysis for overall survival in mixed medical/surgical AKI populations, though continuous therapy may be essential for a small, high-mortality subgroup.

Impact:

• Highlights the importance of timely and adequate dialysis in managing AKI and MOF in critical care settings.
• Suggests specific dialysis dose targets for both continuous and intermittent modalities.
• Underscores the need for further research into optimal treatment strategies for specific AKI patient subgroups, particularly those with severe prognoses.