Evaluation of portable bladder ultrasound: accuracy and effect on nursing practice in an acute care neuroscience unit

The purpose of this evaluation was to determine the accuracy of a portable ultrasound instrument in assessing bladder volume in an acute care neuroscience population and the effect of ultrasound assessment on nursing practice in an acute care neuroscience unit. In a 6-week prospective evaluation, 105 paired ultrasound measurements were performed by 45 nurses on 30 patients suspected to be retaining urine. Sixty-seven catheterizations were performed, and volumes were compared with corresponding ultrasound readings. The first ultrasound volume readings slightly underestimated the catheterized volumes, but the volumes from the first ultrasound readings and the catheterized volumes were highly correlated. Volume readings from a second ultrasound, the average of the first and second ultrasound readings, and the higher of the two ultrasound readings did not add to the ability of the ultrasound instrument to predict catheterized volumes. Patient age and gender did not change the relationship between ultrasound and catheterized volumes. The ultrasound assessment changed nursing practice in 51% of the instances; the most common change (32%) was that nurses did not catheterize the patient. The ultrasound assessment did not change nursing practice in 49% of the instances; the most common reason (41%) was that the ultrasound confirmed the need to catheterize the patient. The instrument was therefore judged to be an accurate and reliable tool that changed nursing practice in an acute care neuroscience unit.