Evaluation of Novel Optical Smartphone Application for Blood Pressure Measurements in Critically Ill Patients

The purpose of the study is to compare the blood pressure values measured by a novel mobile phone application ( camera of the smartphone will be obstructed by the patient's right index) and the values measured by reference method used (the radial arterial line)

All patients admitted in the intensive care unit at Erasme Hospital Brussels, Belgium will be recruited and if they have an arterial line for at least two days

The OptiBP Application is a mobile application installed on a mobile phone which is a non-invasive data-logger intended to acquire physiological data from patients. By applying the patient's finger on a smartphone's camera, a movie is generated and transformed into values of diastolic, mean and systolic blood pressure.

Three measures will be taken (spaced by one minute) with both methods each hour for 5 hours and this will be done for 2 days.

The patient's blood pressure will be measured in parallel with the mobile application and with the reference equipment (arterial line).

Then, the values obtained by the two methods will be compared to confirm the reliability of the data obtained with the novel mobile application.

The goal is therefore to compare blood pressure values as obtained by the analysis of the data recorded by the OptiBP Mobile Application, against simultaneous measurements provided by the arterial line (gold standard)

Inclusion criteria

• All Intensive care unit patients with an arterial catheter for at least 48 hours
• Informed Consent as documented by signature

Exclusion criteria

• Patients or families that cannot sign informed consent
• Patients in emergency situation, and unstable
• Dyshythmia like bigeminy, trigeminy, isolated Ventricular Premature Beats (VPB), atrial fibrillation
• Lesion or deficiency on hand, preventing index obstruction of smartphone's camera
• Known contact dermatitis to nickel/chromium