Computers in biology and medicine
-
Detection of non-cerebral activities or artifacts, intermixed within the background EEG, is essential to discard them from subsequent pattern analysis. The problem is much harder in neonatal EEG, where the background EEG contains spikes, waves, and rapid fluctuations in amplitude and frequency. Existing artifact detection methods are mostly limited to detect only a subset of artifacts such as ocular, muscle or power line artifacts. ⋯ The accuracy obtained using the proposed method is found to be about 20% higher than that of the reference approaches. Joint use of the proposed method with our previous work on burst detection outperforms reference methods on simultaneous burst and artifact detection. As the proposed method supports detection of a wide range of artifact patterns, it can be improved to incorporate the detection of artifacts within other seizure patterns and background EEG information as well.
-
In mechanically ventilated patients, Pulse Pressure Variation (PPV) has been shown to be a useful parameter to guide fluid management. We evaluated a real-time automated PPV-algorithm by comparing it to manually calculated PPV-values. In 10 critically ill patients, blood pressure was measured invasively (IBP) and non-invasively (CNAP(®) Monitor, CNSystems Medizintechnik, Austria). ⋯ PPVautoIBP was -0.19 ± 1.65% (mean bias ± standard deviation), PPVmanCNAP vs. PPVautoCNAP was -1.02 ± 2.03% and PPVautoCNAP vs. PPVmanIBP was -2.10 ± 3.14%, suggesting that the automated CNAP(®) PPV-algorithm works well on both blood pressure waveforms but needs further clinical evaluation.
-
A computerized decision support system is described to predict the changes in the cerebral blood flow (CBF) of mechanically ventilated infants in response to different ventilatory settings. A CBF controller was developed and combined with a mathematical model of the infant's respiratory system to simulate the effects of ventilatory settings on the infant's CBF. ⋯ These included the results obtained under conditions of hypoventilation, hyperventilation, hypoxia, and hyperoxia. The presented decision support system has the potential to be used as an aide to the intensivist in choosing appropriate ventilation treatments for infants to prevent the untoward consequences of hazardous changes in CBF in mechanically ventilated infants such as hypoxic-ischemic brain injuries.
-
The effects of intervertebral disc (IVD) degeneration on biomechanics of the lumbar spine were analyzed. Finite element models of the lumbar spine with various degrees of IVD degeneration at the L4-L5 functional spinal unit (FSU) were developed and validated. With progression of degeneration, intersegmental rotation at the degenerated FSU decreased in flexion-extension and left-right lateral bending, intradiscal pressure at the adjacent FSUs increased in flexion and lateral bending, and facet joint forces at the degenerated FSU increased in lateral bending and axial rotation. These results could provide fundamental information for understanding the mechanism of injuries caused by IVD degeneration.
-
Anaesthesia monitoring involves critical diagnostic tasks carried out amongst lots of distractions. Computers are capable of handling large amounts of data at high speed and therefore decision support systems and expert systems are now capable of processing many signals simultaneously in real time. ⋯ This paper presents the design aspects of these two systems which employ fuzzy logic techniques to detect absolute hypovolaemia, and compares their performances in terms of usability and acceptability. The interpretation of these two systems of absolute hypovolaemia was compared with clinicians' assessments using Kappa analysis, RT-SAAM K=0.62, FLMS-2 K=0.75; an improvement in performance by FLMS-2.