Gravity in Flow: Automating Diuresis

Accurate monitoring of urine output is essential in the management of hospitalized patients, particularly those with hemodynamic instability or fluid balance disorders. Currently, diuresis monitoring is performed manually by nursing staff, which is labor intensive and prone to transcription or timing errors. The FlowSure system is an automated urine output monitoring device designed to continuously measure and record urine production and transfer these data directly to the electronic medical record (EMR). Automation may improve data quality, reduce nursing workload, and enhance patient safety.

This study consists of two parts. Part A is a technical feasibility study in which patients are simultaneously monitored using both manual and automated FlowSure systems to evaluate concordance between the two methods under real-world conditions. Part B is a two-arm randomized, non-blinded intervention study comparing automated versus manual urine output monitoring. Patients will be randomized in a 1:1 ratio to either standard manual monitoring or automated FlowSure monitoring. Randomization occurs after insertion of a urinary catheter, which is placed for medical reasons unrelated to the study.

The primary objective of Part B is to assess the accuracy of urine production measurement by the automated FlowSure monitor compared with manual monitoring over two time frames: (1) an 8-hour nursing shift and (2) a full 24-hour period. The primary endpoint is the completeness and accuracy of hourly diuresis registration between the two monitoring methods. Secondary analyses will include evaluation of data recording efficiency and the rate of missing or incorrect entries in the EMR.

There is no direct therapeutic benefit to participants. The anticipated scientific and societal benefit lies in improving the reliability and efficiency of diuresis monitoring, potentially enhancing patient care and reducing nursing workload. The risks associated with participation are minimal. In Part A, the automated monitor operates in addition to the manual system; in Part B, patients are monitored using only one method. In case of device malfunction or data loss, urine output can be estimated from total collected volume over time. Given the low risk profile and the potential to improve clinical monitoring practices, the overall risk-benefit balance of the study is considered favorable.

Inclusion criteria

• Age 18 years or older.
• Currently hospitalized.
• Indwelling urinary catheter inserted for medical reasons unrelated to the study.
• Able and willing to provide written informed consent.
• No specific urological problems.

Exclusion criteria

• No urinary catheter in place.
• Diuresis < 30 mL per hour at screening.