Preliminary study of motion artifact rejection for NIBP measurement in an ambulance.

Motion artifact resulting from patient's movement is a significant source for disturbing accurate noninvasive blood pressure (NIBP) measurement. In an ambulance, patients are exposed to unstable circumstances due to vehicle's movement and vibration during emergency transportation. Since NIBP is indirectly measured using oscillometry based on the change of cuff pressure, it can be affected by motion artifact much more than other biosignals. In this paper, we developed a new NIBP system with improved accuracy by measuring acceleration of the system caused by patient's motion. The NIBP module including a 3-axis accelerometer was directly mounted on a cuff to minimize the interference induced through connecting tube. The results show that the proposed NIBP system has the capability to reject the interference of motion artifact effectively in an ambulance.