Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference
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Conf Proc IEEE Eng Med Biol Soc · Jan 2008
Evaluation of a tactile display around the waist for physiological monitoring under different clinical workload conditions.
In this study, we have assessed the usability of a tactile belt prototype for clinical monitoring of physiologic patient data in the operating room under low workload (LW) and high workload (HW) conditions. In previous investigations, we have evaluated tactile technology in clinical settings and demonstrated that anesthesiologists have enhanced situational awareness towards adverse clinical events when a tactile display prototype is used as a supplemental monitoring device. To further evaluate the effectiveness of our tactile belt prototype, we compared the effects of workload on the performance of anesthesiologists in terms of accuracy and response time in tactile alert identification. ⋯ We found that the response time to tactile alert identification to be faster under LW than under HW, however the accuracy of identification was not statistically different. Participants rated the tactile belt prototype as comfortable to use and the tactile alert scheme as easy to learn. Our findings further support the feasibility and efficacy of vibrotactile devices for enhancing physiological monitoring of patients in clinical environments.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2008
Comparative StudyPower analysis of gamma frequencies (30 - 47Hz), adjusting for muscle activity (80 - 97Hz), in anesthesia: a comparison between young adults, middle-aged and the elderly.
This study looks at the role of EEG gamma activity, and the influence of facial EMG (80-97 Hz), in predicting consciousness during anesthesia. It also studies the association between the conventional depth of anesthesia index, BIS (Aspect Medical Systems), and EEG gamma and EMG activity. Data has been collected from 21 adult patients and grouped into young adults (18 - 39 yrs, n=3), middle-aged (40 - 64 yrs, n=10) and the elderly (65+ yrs, n=8). ⋯ There are two exceptions to this. In the young adults group there is a stronger association between BIS index and EEG gamma than there is between BIS index and EMG. In the elderly group, the state of consciousness is equally associated with EEG gamma and EMG recorded from the Masseter, but not with the EMG recorded from Fpz.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2008
Removal of ECG artifacts from EEG using a modified independent component analysis approach.
In this paper, we introduce a new automatic method for electrocardiogram (ECG) artifact elimination from the electroencephalogram (EEG) or the electrooculogram (EOG). It is based on a modification of the independent component analysis (ICA) algorithm which gives promising results while only using a single-channel EEG (or EOG) and the ECG. ⋯ Two hundred successive interference peaks were examined in each excerpt to compute correction rates. We found that our modified ICA was the most robust to various waveforms of cardiac interference and to the presence of others artifacts, with a correction rate of 91.0%, against 83.5% for EAS and 83.1% for AF.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2008
Imaging of simulated crackle sounds distribution on the chest.
Crackles sounds have been associated with several pulmonary pathologies and diverse algorithms have been proposed for extracting and counting them from the acquired lung sound. These tasks depend among other factors, of the relation between the magnitude of the crackle and the background lung sound. In this work, we explore multivariate signal processing to deal with the tasks and propose a new concept, the discontinuous adventitious sounds imaging. ⋯ In the first case, the AR coefficients feed an artificial neural network (ANN) to classify temporal acoustic information as healthy or sick and; in the second case, a time-variant AR (TVAR) model, obtained by the RLS algorithm, permits to detect changes in the TVAR coefficients to be associated with the number of crackles. For AR-ANN, the ratio of the temporal windows classified as sick to the classified as healthy is used as an index to form the adventitious image, while for TVAR-RLS, an estimation of the number of crackles is obtained to form the corresponding image. The results indicated that fine and coarse crackles could be detected and counted even with very low crackle magnitude so that the formation of a crackle distribution image was consistent.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2008
EEG spectral changes and onset of burst suppression pattern in propofol/remifentanil anesthesia.
This paper studies how remifentanil, a commonly used intraoperative opioid, affects the relation of the onset of burst suppression pattern (BSP) and the spectral changes of EEG during anesthesia. The onsets of BSP were detected using both manual and the automatic method proposed from the EEGs of twenty-seven patients who had received different amount of remifentanil with the anesthetic. ⋯ The results showed that remifentanil significantly affects the relation of EEG spectral changes and the onset of BSP. The finding is important since the current EEG-based assessment of the depth of anesthesia basically relies on the analysis of the spectral features and BSP.