OptiBP: A novel optical smartphone application for measuring Hypertension

OptiBP which is a new optical smartphone application showed almost similar values to the invasively measured blood pressure values as per a new study published in BMC Anesthesiology. The values were according to the AAMI/ISO universal standards for mean arterial pressure (MAP) and diastolic arterial pressure (DAP). The error risk was also in zone A and B of the error grid. 

Arterial hypertension is a global public health concern. The oscillometric method is presently used for diagnosing and monitoring non-invasively. Better screening and monitoring of hypertension occurs when the same can be done using a smartphone application. So, researchers conducted an observational study on intensive care unit patients by comparing the arterial blood pressure values obtained using a new optical smartphone application called the OptiBP™ as the test method and with that obtained using a radial artery catheter as the reference method to help validate the technology. 

Three BP values were measured every hour for five consecutive hours on two consecutive days using both the smartphone and arterial methods. Bland-Altman and error grid analyses were used for agreement analysis between both approaches. The performance of the smartphone application was investigated using the Association for the Advancement of Medical Instrumentation (AAMI) and the International Organization for Standardization (ISO) definitions, which require the bias ± SD between two technologies to be below 5 ± 8 mmHg. 

Findings:

• 30 patients were recruited for the study, of which 22 patients had adequate OptiBP™ values and were thus analyzed.
• In the other 8 patients, no BP could be measured due to inadequate signals.
• The Bland–Altman analysis revealed a mean of the differences ± SD between both methods of 0.9 ± 7 mmHg for mean arterial pressure (MAP), 0.2 ± 14 mmHg for systolic arterial pressure (SAP), and 1.1 ± 6 mmHg for diastolic arterial pressure (DAP).
• Error grid analysis demonstrated that the proportions of measurement pairs in risk zones A to E were 88.8% (no risk), 10% (low risk), 1% (moderate risk), 0% (significant risk), and 0% (dangerous risk) for MAP and 88.4%, 8.6%, 3%, 0%, 0%, respectively, for SAP. 

OptiBP™ can pave the way for widespread access to hypertension screening and monitoring as it has shown good agreement between BP values measured invasively with that using the application. 

Further reading:

Desebbe, O., Anas, C., Alexander, B. et al. Evaluation of a novel optical smartphone blood pressure application: a method comparison study against invasive arterial blood pressure monitoring in intensive care unit patients. BMC Anesthesiol 22, 259 (2022). https://doi.org/10.1186/s12871-022-01797-0