A new electronic urine meter (UREXACT) is more accurate in measuring urine output than the standard Urinometer: a comparative study

Introduction

Urine output (UO) measurement is an essential part of fluid balance management while caring for critically ill patients. Moreover, it is the most reliable reflection of organ perfusion. The traditional way of monitoring UO is by visual hourly readings of the amount of urine accumulated in a 'scaled container' = Urinometer. These vary according to nurses' technical and visual inaccuracies.

Hypothesis

An electronic flow meter (Urexact) will measure UO in a much more accurate, efficient, user-friendly and 'hands-off' manner than the nurses/Urinometer.

Methods

Adult ICU patients who were expected to be in the ICU ≥ 24 hours were enrolled. UO was measured hourly by the standard Urinometer (nurse) or by the Urexact, for 10 hours each. Hourly urine volume was validated in both techniques by a 'measuring cylinder' operated by a laboratory technician (accuracy of ± 1 ml). Medical personnel completed a questionnaire regarding satisfaction using the Urexact.

Results

Eighty percent of the Urexact measurements were accurate within ± 10% of the actual 'cylinder measurement' versus only 65% of the Urinometer measurements. Eighty-six percent of the nurses graded the Urexact as a very-easy/easy instrument to operate reliably, while saving time and avoiding urine contact.

Conclusions

Urexact is an accurate, easy-to-use and time-saving device, compared with the standard Urinometer. It is well accepted by the ICU staff and allows them to measure UO without urine contact. It has the potential to allow for fully computerized real-time management of fluid balance.

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