Intensive care unit continuous kidney replacement therapy: time to change dosage recommendations?

Area of Science:

• Nephrology
• Intensive Care Medicine
• Critical Care

Background:

• Continuous kidney replacement therapy (CKRT) is vital for hemodynamically unstable ICU patients with severe acute kidney injury (AKI).
• CKRT effectiveness hinges on delivered doses, with current KDIGO guidelines recommending 20-25 ml/kg/hour, potentially higher for some patients.
• Worldwide practice patterns for CKRT dosing are highly variable, necessitating a clearer understanding of treatment adequacy.

Purpose of the Study:

• To investigate the clinical relevance of CKRT dosing in critically ill patients.
• To determine the minimum effective CKRT dose that prevents harm, particularly in specific patient populations like those with obesity or COVID-19.
• To address the unmet need for prospective trials defining optimal CKRT intensity.

Main Methods:

• Review of current KDIGO guidelines and landmark trials on CKRT dosing.
• Analysis of data from Japanese ICU patients receiving CKRT for severe AKI, noting median delivered doses.
• Consideration of findings from retrospective cohort studies, such as Okamoto et al., linking low CKRT doses to increased mortality.

Main Results:

• Landmark trials indicate no benefit from exceeding recommended CKRT doses in unselected AKI patients.
• Japanese ICU patients typically receive lower CKRT doses (median 15 ml/kg/hour) than KDIGO recommendations.
• A retrospective study linked lower delivered CKRT doses to higher mortality in critically ill AKI patients, challenging the adequacy of doses below 20 ml/kg/hour.

Conclusions:

• There is a critical need for prospective randomized trials to establish the minimum effective CKRT dose.
• CKRT doses should be individualized within KDIGO guidelines, considering patient-specific factors.
• The Japanese experience with lower-dose CKRT does not alter current practice-changing recommendations but underscores the importance of adequate dosing.