Journal of clinical monitoring and computing
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J Clin Monit Comput · Jun 2019
Acute pain intensity monitoring with the classification of multiple physiological parameters.
Current acute pain intensity assessment tools are mainly based on self-reporting by patients, which is impractical for non-communicative, sedated or critically ill patients. In previous studies, various physiological signals have been observed qualitatively as a potential pain intensity index. On the basis of that, this study aims at developing a continuous pain monitoring method with the classification of multiple physiological parameters. ⋯ With facial electromyogram, the adaptivity of this method to a new subject was improved as the recognition accuracy of moderate/severe pain in leave-one-subject-out cross-validation was promoted from 74.9 ± 21.0 to 76.3 ± 18.1%. Among healthy volunteers, GSR, HR and BR were better correlated to pain intensity variations than facial muscle activities. The classification of multiple accessible physiological parameters can potentially provide a way to differentiate among no, mild and moderate/severe acute experimental pain.
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J Clin Monit Comput · Jun 2019
Effect of neuromuscular blockade on transcranial electric motor evoked potentials during surgical correction for idiopathic scoliosis under total intravenous anesthesia.
Transcranial electric motor evoked potentials (TCeMEPs) play an important role in reducing the risk of iatrogenic paraplegia. TCeMEPs could be obviously suppressed by neuromuscular blockade (NMB). The aims of this study were to examine the effects of NMB on TCeMEPs and to determine an appropriate level of partial neuromuscular blockade (pNMB) for TCeMEPs during surgical correction of idiopathic scoliosis under total intravenous anesthesia (TIVA). ⋯ Neither the amplitude and AUC nor the efficacy of TCeMEPs were affected at TOF4-5 of abductor halluces muscles TCeMEPs (AH-TCeMEPs) or at TOF3-5 of tibialis anterior muscles TCeMEPs (TA-TCeMEPs) compared with nNMB. However, the rate of unexpected movement was increased significantly at TOF5 and nNMB compared with TOF1 and TOF4. The application of pNMB with TOFR aimed at 26-50% for AH-TCeMEPs or 16-50% for TA-TCeMEPs seems to be an appropriate regimen for TCeMEPs during surgical correction for idiopathic scoliosis under TIVA.
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J Clin Monit Comput · Jun 2019
Thoracic fluid content: a novel parameter for detection of pulmonary edema in parturients with preeclampsia.
Acute pulmonary oedema is a serious complication of preeclampsia. Early detection of pulmonary edema in preeclampsia would improve fluid management and would also allow earlier detection of severe cases. The aim of this work is to evaluate the ability of thoracic fluid content measured by electrical cardiometry for early detection of pulmonary edema in parturients with preeclampsia. ⋯ In parturients with preeclampsia, both lung ultrasound score and thoracic fluid content showed excellent properties for detection pulmonary edema. The high negative predictive value of both tests makes them useful screening tests to rule out pulmonary edema. The excellent correlation between both measures suggests that electrical cardiometry could be a promising surrogate to ultrasound for assessment of extravascular lung water.
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J Clin Monit Comput · Jun 2019
Comparative Study Observational StudyCardiac output and stroke volume variation measured by the pulse wave transit time method: a comparison with an arterial pressure-based cardiac output system.
Hemodynamic monitoring is mandatory for perioperative management of cardiac surgery. Recently, the estimated continuous cardiac output (esCCO) system, which can monitor cardiac output (CO) non-invasively based on pulse wave transit time, has been developed. Patients who underwent cardiovascular surgeries with hemodynamics monitoring using arterial pressure-based CO (APCO) were eligible for this study. ⋯ The time course had no effects on the biases between CO and SVV. Concordance rates were 80.3 and 75.7% respectively. While CO measurement with esCCO can be a reliable monitor after cardiovascular surgeries, SVV measurement with esCCO may require further improvement.
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J Clin Monit Comput · Jun 2019
Optimizing target control of the vessel rich group with volatile anesthetics.
The ability to monitor the inspired and expired concentrations of volatile anesthetic gases in real time makes these drugs implicitly targetable. However, the end-tidal concentration only represents the concentration within the brain and the vessel rich group (VRG) at steady state, and very poorly approximates the VRG concentration during common dynamic situations such as initial uptake and emergence. How should the vaporization of anesthetic gases be controlled in order to optimally target VRG concentration in clinical practice? Using a generally accepted pharmacokinetic model of uptake and redistribution, a transfer function from the vaporizer setting to the VRG is established and transformed to the time domain. ⋯ Using a simple and clinically intuitive modification to the targeting algorithm, a variable low-pass boundary layer is applied to the actuation, smoothing discontinuities in the control law and practically eliminating chatter without prolonging the time taken to reach the VRG target concentration by any clinically significant degree. A model is derived for optimum VRG-targeted control of anesthetic vaporizers. An alternate and further application is described, in which deliberate perturbation of the vaporization permits non-invasive estimation of parameters such as cardiac output that are otherwise difficult to measure intra-operatively.