Journal of clinical monitoring and computing
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This paper addresses the problem of patient model synthesis in anesthesia. Recent advanced drug infusion mechanisms use a patient model to establish the proper drug dose. However, due to the inherent complexity and variability of the patient dynamics, difficulty obtaining a good model is high. ⋯ Then, an adaptive strategy that uses genetic algorithms is implemented. The validation of the modeling technique was done using real data obtained from real patients in the operating room. Results show that the proposed method based on artificial intelligence appears to be an improved alternative to existing compartmental methodologies.
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J Clin Monit Comput · Apr 2017
The effects of ventricular drainage on the intracranial pressure signal and the pressure reactivity index.
In subarachnoid hemorrhage (SAH) patients intracranial pressure (ICP) is usually monitored via an extraventricular drain (EVD), which can produce false readings when the drain is open. It is established that both the ICP cardiac pulse frequency and long term trends over several hours are often seriously corrupted. The aim of this study was to establish whether or not the intermediate frequency bands [respiratory, Mayer wave and very low frequency (VLF)] were also corrupted. ⋯ We found a small but statistically significant decrease during open-drain periods. Based on analysis of the change in the PRx distribution during open drainage we concluded that this decrease also represented physiological changes rather than artifact. In summary the ICP respiratory, Mayer wave, and VLF frequency bands are not corrupted when the EVD is open, and it safe to use these for autoregulation studies.
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J Clin Monit Comput · Apr 2017
To characterize the incidence of airway misplacement of nasogastric tubes in anesthetized intubated patients by using a manometer technique.
This study characterized the incidence of airway misplacement of nasogastric (NG) tubes in surgical patients, and the benefit of using a manometer to discriminate gastric placement from airway placement of NG tubes. Subjects included adult patients scheduled for abdominal surgery. After tracheal intubation, a 16 Fr. ⋯ For confirmation of gastric placement, the auscultation technique had a sensitivity of 100.0 % and a specificity of 79.3 %. In contrast, the manometer technique had a sensitivity of 100.0 % and a specificity of 100.0 % in the discrimination of gastric placement from airway placement of NG tubes. Airway misplacement of NG tubes is not uncommon in surgical patients, and the manometer technique may be a reliable and safe method to discriminate gastric placement from airway placement of NG tubes.
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J Clin Monit Comput · Apr 2017
Observational StudyHeart rate time series characteristics for early detection of infections in critically ill patients.
It is difficult to make a distinction between inflammation and infection. Therefore, new strategies are required to allow accurate detection of infection. Here, we hypothesize that we can distinguish infected from non-infected ICU patients based on dynamic features of serum cytokine concentrations and heart rate time series. ⋯ There was no significant additional value of adding static cytokine levels or cytokine time series information to the generated decision tree model. The results suggest that heart rate is a better marker for infection than information captured by cytokine time series when the exact stage of infection is not known. The predictive value of (expensive) biomarkers should always be weighed against the routinely monitored data, and such biomarkers have to demonstrate added value.