Author
- Hanna Costa Carvalho
- Joel DeVries
- Danny Kelly
- Aliza Klein
- Sikhulile Vilane
Mentor
Dr. Lalor, Dr. Marinesku
Abstract
Background
Blood oxygen Saturation (Sp02) is regarded as the fifth vital sign. Traditionally, a pulse oximeter is used to measure Sp02. A pulse oximeter measures Sp02 by sending light through the body (typically the finger) and calculating the reflected red and infrared light. In this process, the arterial blood is differentiated by its pulsatile nature. In the Cardiac Intensive Care Unit (CICU), patients who have suffered severe trauma to the heart are placed on Extracorporeal Membrane Oxygenation (ECMO) machines or Left Ventricular Assist Devices (LVADs) which operate off of continuous blood flow so a pulse oximeter can not be used. Our customer, Dr. Marinescu manually palpates the patient’s brachial artery so that a pulse oximeter can be used. One problem with this solution is that oxygen saturation can not be monitored continuously.
Design Overview
The device uses a solenoid that is placed on the brachial artery of the patient and this will mechanically induce a pulse on the patient, and a pulse oximeter can be used to measure saturated oxygen levels. The device is powered by batteries although other power sources can be used depending on the clinical setting needs. A microcontroller system controls the speed and force of the solenoid. All components of the device have been placed on an adjustable strap for easy setup and use. As the solenoid fires, waves of pressure flow down the brachial artery to arteries in the finger where a pulse oximeter would be placed to obtain arterial blood oxygen saturation values.
Testing
The testing was centered around whether the device can create pulsatile blood flow sensed by the Powerlab Pulse Transducer. The device was placed properly over the brachial artery of the subject and a normal pulse was obtained. Then the device was turned on. This was done both when the brachial artery of the subject was occluded and not occluded.
Results and Discussion
The findings provide promising preliminary evidence supporting the effectiveness of our device in mechanically inducing a pulse. Since the testing was done on healthy individuals, the next step would be to extend our research by conducting clinical trials with patients. This will allow validation of the device in inducing a pulse on pulseless patients.