Journal of clinical monitoring and computing
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J Clin Monit Comput · Dec 2016
Utility of the bispectral index for assessing natural physiological sleep stages in children and young adults.
Polysomnography (PSG) is the gold standard for the analysis of sleep architecture but is not always available in routine practice, as it is time consuming and cumbersome for patients. Bispectral index (BIS), developed to quantify the deepness of general anesthesia, may be used as a simplified tool to evaluate natural sleep depth. We objectively recorded sleep architecture in young patients using the latest BIS Vista monitor and correlated BIS values with PSG sleep stages in order to determine BIS thresholds. ⋯ BIS threshold that identified stage N3 was <55 (AUC = 0.964, p < 0.001) with an 87 %-sensitivity and a 93 %-specificity. BIS identified stage N3 with satisfactory sensitivity and specificity but is limited by its inability to distinguish REM sleep from wake. Further studies combining BIS with chin electromyogram and/or electrooculogram could be of interest.
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J Clin Monit Comput · Dec 2016
Effect of using a Planecta™ port with a three-way stopcock on the natural frequency of blood pressure transducer kits.
Blood pressure transducer kits are equipped with two types of Planecta™ ports-the flat-type Planecta™ port (FTP) and the Planecta™ port with a three-way stopcock (PTS). We reported that FTP application decreased the natural frequency of the kits. However, Planecta™ is an invaluable tool as it prevents infection, ensures technical simplicity, and excludes air. ⋯ The insertion of ≥2 FTPs in pressure transducer kits should be avoided, as they markedly decrease the natural frequency and lead to underdamping. However, the effect of PTS insertion in pressure transducer kits on the frequency characteristics is minimal. Thus, we found that the use of PTS markedly improved the frequency characteristics as compared to the use of FTP.
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J Clin Monit Comput · Dec 2016
Real alerts and artifact classification in archived multi-signal vital sign monitoring data: implications for mining big data.
Huge hospital information system databases can be mined for knowledge discovery and decision support, but artifact in stored non-invasive vital sign (VS) high-frequency data streams limits its use. We used machine-learning (ML) algorithms trained on expert-labeled VS data streams to automatically classify VS alerts as real or artifact, thereby "cleaning" such data for future modeling. 634 admissions to a step-down unit had recorded continuous noninvasive VS monitoring data [heart rate (HR), respiratory rate (RR), peripheral arterial oxygen saturation (SpO2) at 1/20 Hz, and noninvasive oscillometric blood pressure (BP)]. Time data were across stability thresholds defined VS event epochs. ⋯ ML algorithms applied to the Block 1 training/cross-validation set (tenfold cross-validation) gave area under the curve (AUC) scores of 0.97 RR, 0.91 BP and 0.76 SpO2. Performance when applied to Block 2 test data was AUC 0.94 RR, 0.84 BP and 0.72 SpO2. ML-defined algorithms applied to archived multi-signal continuous VS monitoring data allowed accurate automated classification of VS alerts as real or artifact, and could support data mining for future model building.
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J Clin Monit Comput · Dec 2016
Randomized Controlled TrialEvaluation of the brain anaesthesia response monitor during anaesthesia for cardiac surgery: a double-blind, randomised controlled trial using two doses of fentanyl.
The brain anaesthesia response (BAR) monitor uses a method of EEG analysis, based on a model of brain electrical activity, to monitor the cerebral response to anaesthetic and sedative agents via two indices, composite cortical state (CCS) and cortical input (CI). It was hypothesised that CCS would respond to the hypnotic component of anaesthesia and CI would differentiate between two groups of patients receiving different doses of fentanyl. Twenty-five patients scheduled to undergo elective first-time coronary artery bypass graft surgery were randomised to receive a total fentanyl dose of either 12 μg/kg (fentanyl low dose, FLD) or 24 μg/kg (fentanyl moderate dose, FMD), both administered in two divided doses. ⋯ Following the first dose of fentanyl, CI, CCS and BIS decreased in both groups. Following the second dose of fentanyl, there was a significant reduction in CI in the FLD group but not the FMD group, with no significant change found for BIS or CCS in either group. The BAR monitor demonstrates the potential to monitor the level of hypnosis following anaesthesia induction with propofol via the CCS index and to facilitate the titration of fentanyl as a component of balanced anaesthesia via the CI index.
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J Clin Monit Comput · Dec 2016
Randomized Controlled TrialChanges in intraocular pressure during surgery in the lateral decubitus position under sevoflurane and propofol anesthesia.
Intraocular pressure (IOP) has been shown to change with body position. Several studies have shown that the lateral decubitus position (LDP) is associated with a significant increase in IOP in the dependent eye. However, whether anesthetic agents alter IOP in the LDP remains unclear. ⋯ The number of patients in whom IOP increased to ≥28 mmHg was greater in the sevoflurane group than in the propofol group. Propofol may be better than sevoflurane for the maintenance of anesthesia in the LDP. Monitoring of IOP in the LDP might help avoid ophthalmic complications.