Interruptions and downtime of continuous renal replacement therapy in critically ill adults: A retrospective observational study.

Background: The effective treatment time of continuous renal replacement therapy (CRRT) is significantly important. Downtime caused by interruptions is still unclear during a circuit filter.

Aim: This study aimed to analyse the interruptions and downtime during a circuit filter through the data recorded by the internal data storage cards of the CRRT machine.

Methods: This is a single-centre retrospective observational study. From August 2019 to April 2020, all patients who received CRRT treatment with the Prismaflex device (Gambro, America) were enrolled.  After downloading the data from the internal data storage cards, it was meticulously sorted and verified using Excel. Statistical analyses were performed using SPSS software (version 22.0).

Results: A total of 143 CRRT circuits in 59 patients were analysed. The overall median circuit life was 39.22 (IQR, 24.07-60.25) h, median amount of interruption was 67 (IQR, 42-100), causing a median downtime of 1.98 (IQR, 1.20-2.85) h and a median downtime proportion (ratio of downtime/circuit life) of 4.58% (IQR, 3.50-6.69). Circuit downtime was mainly caused by bag change (1.17 ± 0.66 h [p < 0.001]). Circuits in the group of downtime proportion >10% had longer downtime (2.53 ± 3.37 h, p < 0.001) and more circuit alarms (45.54 ± 42.87, p < 0.001), and alarms cost much more time to be fixed (1.03 [IQR, 0.42-2.24] h, p < 0.001). No variation was found in downtime among groups according to circuit lifespan.

Conclusions: Interruptions in a circuit can accumulate into non-negligible downtime. Specialized nursing actions through education and training are of great significance to avoid unnecessary interruptions.

Relevance To Clinical Practice: Nurses' behaviour is related to the downtime of CRRT. Intensive care unit (ICU) nurses should be trained to inculcate the behaviours, including keeping sufficient bags at patient's bedside, changing solution bags actively, adressing alarms swiftly, arranging the examinations and the initiation of a CRRT reasonably.