Journal of clinical monitoring and computing
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J Clin Monit Comput · Dec 2005
Comparative StudyComparison of the EEG-based SNAP index and the Bispectral (BIS) index during sevoflurane-nitrous oxide anaesthesia.
The BIS monitor (Aspect Medical Inc, Newton, USA) was the first electroencephalogram (EEG)-based monitor of the hypnotic effect reflected by a dimensionless figure ranging from 100 (awake state) to 0 (flat line EEG). Its widespread use makes it the most-studied and the best-known among same intended devices. Its algorithm processes low-frequency EEG oscillations in order to provide the Bispectral index. ⋯ The Bland and Altman test showed a bias of 14.3 for SNAP index values with respect to BIS index values. We concluded that the SNAP index correlates with variations in the hypnotic effect induced by sevoflurane-nitrous oxide anaesthesia when compared with the BIS index. In this context, a SNAP index ranging from 58 to 70 would be equivalent to the BIS index range 40 to 60 and, therefore, the accurate for surgical performance.
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J Clin Monit Comput · Dec 2005
Practice GuidelineIntraoperative monitoring of segmental spinal nerve root function with free-run and electrically-triggered electromyography and spinal cord function with reflexes and F-responses. A position statement by the American Society of Neurophysiological Monitoring.
Orthodromic ascending somatosensory evoked potentials and antidromic descending neurogenic somatosensory evoked potentials monitor spinal cord sensory function. Transcranial motor stimulation monitors spinal cord motor function but only activates 4-5% of the motor units innervating a muscle. Therefore, 95-96% of the motor spinal cord systems activating the motor units are not monitored. To provide more comprehensive monitoring, 11 techniques have been developed to monitor motor nerve root and spinal cord motor function. These techniques include: 1. neuromuscular junction monitoring, 2. recording free-run electromyography (EMG) for monitoring segmental spinal nerve root function, 3. electrical stimulation to help determine the correct placement of pedicle screws, 4. electrical impedance testing to help determine the correct placement of pedicle screws, 5. electrical stimulation of motor spinal nerve roots, 6. electrical stimulation to help determine the correct placement of iliosacral screws, 7. recording H-reflexes, 8. recording F-responses, 9. recording the sacral reflex, 10. recording intralimb and interlimb reflexes and 11. recording monosynaptic and polysynaptic reflexes during dorsal root rhizotomy. ⋯ The techniques reviewed in this paper may be helpful to those wishing to incorporate these techniques into their monitoring program.
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J Clin Monit Comput · Dec 2005
Comparative StudyCardiac output measurement by pulse dye densitometry: comparison with pulmonary artery thermodilution in post-cardiac surgery patients.
Pulse-dye densitometry (PDD) could be a suitable, low-invasive alternative to thermodilution using a pulmonary artery catheter (PAC) for monitoring cardiac output. The aim of our study was to assess the reproducibility and validity of PDD compared to PAC-thermodilution. ⋯ PDD correlates well with PAC-thermodilution and thus deserves consideration as a low-invasive alternative for measurement and follow-up of cardiac output.
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J Clin Monit Comput · Dec 2005
Analysis of nighttime activity and daytime pain in patients with chronic back pain using a self-organizing map neural network.
There may be a relationship between sleep and pain in patients with chronic back pain. We collected day-time pain and nighttime activity data from 18 patients diagnosed with chronic back pain. The patients were followed for 6 days and 5 nights. ⋯ Patients who experience large fluctuations in daytime pain levels also show a higher variability in their nighttime activity levels and patterns. Even though we were unable to show a direct relationship between daytime pain and sleep, it may be reasonable to assume that better pain control resulting in less daytime pain fluctuations can provide more stable nighttime activity levels and patterns in this limited group of patients. By using a neural network model, we were able to extract information from the nighttime activity levels even though a traditional statistical analysis was unsuccessful.
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J Clin Monit Comput · Oct 2005
Towards data warehousing and mining of protein unfolding simulation data.
The prediction of protein structure and the precise understanding of protein folding and unfolding processes remains one of the greatest challenges in structural biology and bioinformatics. Computer simulations based on molecular dynamics (MD) are at the forefront of the effort to gain a deeper understanding of these complex processes. Currently, these MD simulations are usually on the order of tens of nanoseconds, generate a large amount of conformational data and are computationally expensive. More and more groups run such simulations and generate a myriad of data, which raises new challenges in managing and analyzing these data. Because the vast range of proteins researchers want to study and simulate, the computational effort needed to generate data, the large data volumes involved, and the different types of analyses scientists need to perform, it is desirable to provide a public repository allowing researchers to pool and share protein unfolding data. ⋯ Web and grid services, especially pre-defined data mining services that can run on or 'near' the data repository of the data warehouse, are likely to play a pivotal role in the analysis of molecular dynamics unfolding data.