Automatic Double Check Monitoring of Continuous Fluid Excretion and Urine Output

Author(s): Nicolas Goy, Philippe Beuret, Alexandre Despond, Reza Porouchani and Jean-Jacques Goy

Introduction: In modern clinical settings, vital signs are typically monitored electronically, except for urine output, which still relies on manual recording. This manual process is prone to human errors. In this study, we assessed, in vitro, the ability of a novel electronic device to measure real-time flow output, such as urine output, using a combination of two different methods.

Methods: Urine output was measured using a combination of gravimetry, with a dynamometer, and capacitive sensing to improve precision. Data were collected in three different flow settings: low (<20 ml/hour), medium (20 to 150 ml/hour), and high (>150 ml/hour). Additionally, two different situations were tested: with the dead space and Pasteur’s chamber either full or empty.

Results: The differences between the injected and measured volumes varied between 2 to 3 ml for the low flow setting, 0 to 2 ml for the medium flow setting, and 0 to 5 ml for the high flow setting. This corresponds to a maximal error of 3%, regardless of the injected volume and flow rate in ml/hour. The capacitive sensors exhibited the expected behavior, producing a parallel curve representing the expected and measured flow.

Conclusion: Our findings demonstrate that accurate measurements of volume and flow output can be achieved by combining gravimetry and capacitive sensor. To confirm the device's usefulness in measuring urine output in real-life clinical settings, clinical trials are necessary.