Metabolic disturbances potentially attributable to clogging during continuous renal replacement therapy

Area of Science:

• Nephrology
• Critical Care Medicine
• Biomedical Engineering

Background:

• Clogging progressively impairs renal replacement device patency due to unknown molecular obstruction.
• Citrate anticoagulation can lead to metabolic alkalosis, hypernatremia, and hypercalcemia during CRRT.
• Increased clogging incidence observed during the COVID-19 pandemic, with unclear contributing factors.

Purpose of the Study:

• To analyze the incidence of CRRT device clogging in critically ill COVID-19 patients.
• To assess time-varying factors associated with the development of clogging.
• To compare clogging rates between different CRRT devices.

Main Methods:

• Retrospective analysis of COVID-19 patients undergoing CRRT (March 2020 - December 2021).
• Assessed clogging surrogates (serum sodium, bicarbonate, calcium) and CRRT device types (multiFiltrate, Prismaflex).
• Employed a mixed-effects model to identify factors associated with clogging.

Main Results:

• Moderate and severe clogging occurred in 15% and 19% of patients, respectively.
• Twenty-seven percent of CRRTs using multiFiltrate devices showed clogging; none with Prismaflex.
• Clogging correlated with elevated triglycerides, enteral nutrition, and increasing white blood cell count.

Conclusions:

• Clogging is a frequent issue in critically ill COVID-19 patients undergoing CRRT.
• Hypertriglyceridemia and systemic inflammation appear to promote secondary membrane formation, compromising filter patency.
• Device-specific differences in clogging incidence warrant further investigation.