Journal of clinical monitoring and computing
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J Clin Monit Comput · Feb 2016
Transient stop-flow arm arterial-venous equilibrium pressure measurement: determination of precision of the technique.
Transient stop-flow arm arterial-venous equilibrium pressure (Pmsf-arm) is a validated technique for measuring the mean systemic filling pressure (Pmsf). Pmsf is a functional measure of the effective intravascular volume status. This study aims to assess the precision of the Pmsf-arm measurement. ⋯ Averaging two, three and four measurements the CE improves to 4 % (±1 %), 3 % (±1 %) and 3 % (±1 %) respectively, and the LSC was reduced to 10 % (±4 %), 8 % (±3 %) and 7 % (±3 %) respectively. One measurement of Pmsf-arm can reliably detect changes on Pmsf-arm of 14 %. The precision of Pmsf-arm technique improves when averaging two or three measurements.
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J Clin Monit Comput · Feb 2016
Clinical TrialTissue microcirculation measured by vascular occlusion test during anesthesia induction.
Tissue microcirculation measured by vascular occlusion test is impaired during septic shock. However, it has not been investigated extensively during anesthesia induction. The aim of the study is to evaluate tissue microcirculation during anesthesia induction. ⋯ There was an inverse correlation between changes in the skin temperature gradients and changes in cerebral oximetry (r = 0.33; p = 0.02). During anesthesia induction, blood pressure and forearm-minus-fingertip skin temperature gradients decrease while cerebral oximetry and vascular occlusion test recovery slope increase. These findings suggest that anesthesia induction increases tissue microcirculation with peripheral vasodilation.
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J Clin Monit Comput · Feb 2016
Monitoring minute ventilation versus respiratory rate to measure the adequacy of ventilation in patients undergoing upper endoscopic procedures.
Endoscopic procedures performed under conscious sedation require careful monitoring of respiratory status to prevent adverse outcomes. This study utilizes a non-invasive respiratory volume monitor (RVM) that provides continuous real-time measurements of minute ventilation (MV), tidal volume and respiratory rate (RR) to assess the adequacy of ventilation during endoscopy. Digital respiratory traces were collected from 51 patients undergoing upper endoscopy with propofol sedation using an impedance-based RVM. ⋯ Low RR measurements alone do not reflect episodes of low MV and are not sufficient for accurate assessment of respiratory status. RVM provides a new way to collect MV measurements which provide more comprehensive data than RR alone. Further work is ongoing to evaluate the use of MV data during procedural sedation.
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J Clin Monit Comput · Feb 2016
In vitro evaluation of an ultrasonic cardiac output monitoring (USCOM) device.
Non-invasive cardiac output monitoring techniques provide high yield, low risk mechanisms to identify and individually treat shock in the emergency setting. The non-invasive ultrasonic cardiac output monitoring (USCOM) device uses an ultrasound probe applied externally to the chest; however limitations exist with previous validation strategies. This study presents the in vitro validation of the USCOM device against calibrated flow sensors and compares user variability in simulated healthy and septic conditions. ⋯ Although there was some variability between users, particularly in the healthy condition (P < 0.01), all estimations were within a clinically acceptable range. In this study the USCOM provided a suitable measurement of cardiac output and heart rate when compared with our in vitro system. It is a promising technique to assist with the identification and treatment of shock.
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J Clin Monit Comput · Feb 2016
Lightweight physiologic sensor performance during pre-hospital care delivered by ambulance clinicians.
The aim of this study was to explore the impact of motion generated by ambulance patient management on the performance of two lightweight physiologic sensors. Two physiologic sensors were applied to pre-hospital patients. The first was the Contec Medical Systems CMS50FW finger pulse oximeter, monitoring heart rate (HR) and blood oxygen saturation (SpO2). ⋯ The RESpeck RR sensor delivered an average of 4.2 (±2.2) validated breaths per minute, but did not produce any validated breaths during the gross motion of ambulance transit as its pre-defined motion threshold was exceeded. However, this was many more data points than could be achieved using traditional manual assessment of RR. Error was identified on a majority of pre-hospital physiologic signals, which emphasised the need to ensure consistent sensor attachment in this unstable and unpredictable environment, and in developing intelligent methods of screening out such error.