Journal of clinical monitoring and computing
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J Clin Monit Comput · Oct 2021
Multi-model generalised predictive control for intravenous anaesthesia under inter-individual variability.
Inter-individual variability possesses a major challenge in the regulation of hypnosis in anesthesia. Understanding the variability towards anesthesia effect is expected to assist the design of controller for anesthesia regulation. However, such studies are still very scarce in the literature. ⋯ Both the parameters [Formula: see text] and [Formula: see text], which are unknown before anesthesia procedure, were found to be highly significant in contributing the uncertainty of BIS. Their range of variability must be considered during the design and evaluation of controller. A linear controller may be sufficient to tackle most of the variability since both [Formula: see text] and [Formula: see text] would be translated into process gain upon linearization.
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J Clin Monit Comput · Oct 2021
Oxygen desaturation and time burden during tracheobronchial endoscopy for suspected foreign body in toddlers.
Tracheobronchial endoscopy with general anaesthesia for suspected foreign body aspiration exposes toddlers to acute hypoxemia. Better quantification of intraoperative hypoxemia could help identify and manage the most severe patients. We explored the hypoxic burden approach to account for both duration and depth of desaturation episodes during the procedure and determined risk factors for high hypoxic burden. ⋯ High hypoxic burden was associated with an increased risk of postoperative invasive ventilation (OR 32, 95% CI 1.7-617) and of hospital stay > 24 h (OR 4.0, 95% CI 1.6-10). No postoperative neurological sequelae were found. The hypoxic burden approach, when applied in tracheobronchial endoscopy for suspected foreign body aspiration in toddlers, enabled the quantification of hypoxemia and the search for specific risk factors.
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J Clin Monit Comput · Oct 2021
Observational StudyForeseeing postoperative pain in neurosurgical patients: pupillometry predicts postoperative pain ratings-an observational study.
Pupillary reflex dilation (PRD) is triggered by noxious stimuli and diminished by opioid administration. In the postoperative period, PRD has been shown to be correlated with pain reporting and a useful tool to guide opioid administration. In this study we assessed whether pupillary measurements taken before extubation were related with the patient's reported pain in the Post-Anesthesia Care Unit (PACU) using the Numerical Rating Scale (NRS). ⋯ We also found a negative correlation between pupil diameter and age (rS = - 0.42, P = 0.04). The statistically significant correlation between pre-extubation PPI scores and NRS scores, as well as between the pupillary diameter before tetanic stimulation and NRS scores suggest the possibility of titrating analgesia at the end of the intraoperative period based on individual responses. This could allow clinicians to identify the ideal remifentanil concentration for the postoperative period.
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J Clin Monit Comput · Oct 2021
Trans-ocular brain impedance index for assessment of cerebral autoregulation in a porcine model of cerebral hemodynamic perturbation.
Cerebrovascular autoregulation (CA) is often impaired following traumatic brain injury. Established technologies and metrics used to assess CA are invasive and conducive for measurement, but not for continuous monitoring. We developed a trans-ocular brain impedance (TOBI) method that may provide non-invasive and continuous indices to assess CA. ⋯ Receiver operator curve test showed high predictive performance of DZx when compared to PRx with area under the curve above 0.86, with high sensitivity and specificity. Impedance indices appear to track changes in PRx and hemodynamics that affect cerebral autoregulation. TOBI may be a suitable less invasive surrogate to PRx and capable of tracking cerebral autoregulation.
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J Clin Monit Comput · Oct 2021
Observational StudyA modified train-of-four ratio to assess recovery from depolarizing neuromuscular blockade after succinylcholine, a prospective observational study.
Succinylcholine is still used in clinical practice. Its duration is highly variable and neuromuscular monitoring is recommended to assess its recovery. Unfortunately, depolarizing neuromuscular block cannot be evaluated by train-of-four (TOF) as no fade occurs. ⋯ It was10.0 [8.0-13.0] min vs 10.0 [8.0-12.0] min, P = 0.307 and 10.0 [9.0-15.0] min vs 10.0 [8.0-15.0] min, P = 0.546; respectively; median [IQR]. Agreement between both parameters was excellent. The T4/Tref can be used accurately to measure recovery from depolarizing neuromuscular block.