Development and perceived usability evaluation of an interactive smartphone application for the teaching of hemodynamics and evaluation of arterial pulse pressure variation

BACKGROUND: The use of fluids is the most frequently used therapy for circulatory shock. Its inadequate use has adverse effects, requiring hemodynamic goals, highlighting the use of pulse pressure variation due to its high accuracy. One of the problems related to this method is the difficulties in measuring the pulse pressure variation (PPV) in most monitors for clinical use. We assessed the qualitative aspects of perceived usability of a smartphone application (app), which, based on a photograph of the patient's arterial pulse wave, can help measure PPV and help in the diagnosis and management of shock cases. METHODS: To assess the software perceived usability, we used the System Usability Scale (SUS) applied to 30 physicians in 2 tertiary hospitals in Brazil. The software accuracy was measured using a sequence of 3 images with different values ​​of pulse pressure variation, comparing the obtained values ​​ with the gold standard. The educational interface of the app was evaluated qualitativelyfrom the spontaneous testimonies of the selected test participants.The project was approved by the Research Ethics Committee of Centro Universitário Christus. RESULTS: The analysis showed an average SUS of 86.3 points on a scale of 1–100 (above 80.3 is considered the best in terms of interface). The assessment of the application's accuracy when evaluating pulse pressure variation showed that the average variation of the measurements taken by the participants was small, with a good measure of repeatability and reproducibility. The app's educational interface was qualitatively evaluated, being praised by the users. CONCLUSIONS: It can be concluded that the developed mobile application showed excellent qualitative aspects of perceived usability results. More studies with this app will be required to evaluate the potential to help professionals with hemodynamic evaluation in emergency and intensive care settings.