AAMI TIR 44 pdf free download

AAMI TIR 44 pdf free download.Non-invasive blood pressure motion artifact – Testing and evaluation of NIBP device performance in the presence of motion artifact.
5 Effect of Artifact on NIBP readings
5.1 Summary of literature
5.1.1 Simulation and Testing
A number of commercial NIBP simulators are available and have the capability to add various types of artifact to the signal 7.89 While these simulators are useful tools for evaluating the performance of NIBP devices under various environmental situations, they are not able to substitute for dinical validation.20
Previous attempts have been made to provide a more robust simulation. A simulator that electronically replayed stored oscillometric signals was described in a published US patent 19 The device supported the addition of artifact signals for performance testing, but it required the modification of the test device in order to accept the electronic signals.
Van Horn et al. modified a commercial NIBP simulator (Bio-Tek BP Pump) so repeatable motion artifact waveforms could be superimposed onto stored oscillometric signals. The artifact waveforms were collected under transport conditions and reproduced by a function generator.3’ This simulator allowed evaluation of the performance of NIBP devices on artifact-corrupted readings compared to the performance on the same signals without artifact.
Amoore et al. developed a simulator that enables previously recorded clinical oscillometric pressure waveforms to be replayed for testing NIBP devices. The authors suggest that a larger waveform database would be required before the simulator could replace clinical studies.3
lyrlboz and Hearon review the various standards for testing BP devices and point out the limitations of these protocols relative to testing during exercise and transport.15 They suggest modification of current clinical protocols by using multiple observers and limiting external artifact sources.
Shang et al addressed the issue of developing a standardized protocol to assess the motion performance of pulse oximeters.° They concluded that a protocol that used visual feedback to guide subject -9enerated movement artifact was a better test than mechanically generated motion. Due to the nature of BP signals, this method would not be applicable
Vibrations experienced by a patient on a hand-held stretcher, in an ambulance, and in a helicopter were measured using accelerometers.1 Three were placed on the stretcher, one on the patient, and one between the patient and the stretcher. This type of data could be used to help develop improved methods of testing BP devices.
5.1.2 Transport
Numerous studies have shown that measurement of blood pressure during patient transport by ground or air ambulance is affected by external noise, 27 vibration and patient movement.16182230 These artifact sources affect the accuracy of BP measurement by auscultation, palpation, 18.22 and oscillometry.161822 27 While direct intra-arterial measurement can provide accurate BP values, it is used most often in restricted circumstances, e.g., CU, CCU, due to potential complications and rarely used in transport. 18,22.27
Methods to improve the performance of automated oscillometric devices include the use of accelerometers to measure and remove artifact caused by patient movement, the use of ECG synchronization to identify physioloic pulsations, ‘ the use of pulse oximeter signals to identify systolic BP, 22 and improved filtering algorithms. 6. .31 Adaptive interference cancellation has been studied as a means to eliminate motion artifact in an automated device based on auscultation.25 The method utilized two acoustic sensors to measure noise signals and a third to measure Korotkoff sounds.AAMI TIR 44 pdf download.