Journal of clinical monitoring and computing
-
J Clin Monit Comput · Dec 2021
Mitochondrial oxygen monitoring with COMET: verification of calibration in man and comparison with vascular occlusion tests in healthy volunteers.
Mitochondria are the primary consumers of oxygen and therefore an important location for oxygen availability and consumption measurement. A technique has been developed for mitochondrial oxygen tension (mitoPO2) measurement, incorporated in the COMET. In contrast to most textbooks, relatively high average mitoPO2 values have been reported. ⋯ The kinetics from this decline are used to mitochondrial oxygen consumption (mitoVO2). This study validates the calibration of the COMET device in humans. For mitoVO2 measurements not only blood flow cessation but application of local pressure is of great importance to clear the measurement site of oxygen-carrying erythrocytes.
-
J Clin Monit Comput · Dec 2021
Simulation study on flow rate accuracy of infusion pumps in vibration conditions during emergency patient transport.
Infusion pumps are frequently used when transferring critically ill patients via patient transport cart, ambulance, or helicopter. However, the performance of various infusion pumps under these circumstances has not been explored. The aim of this study was to evaluate the flow rate accuracy of infusion pumps under various clinical vibration conditions. ⋯ However, in moderate vibration, flow rates in syringe pumps increased beyond their known error ranges, while flow rates in peristaltic pumps remained stable. In extreme vibration, accidental fluid bolus occurred in syringe pumps but not in peristaltic pumps. The newly developed cylinder pump maintained stable performance and was unaffected by external vibration environments.
-
J Clin Monit Comput · Dec 2021
Laser speckle contrast imaging of forehead cutaneous blood flow during carotid endarterectomy as a potential non-invasive method for surrogate monitoring of cerebral perfusion.
Monitoring cerebral perfusion is important for goal-directed anesthesia. Taking advantage of the supply of the supraorbital region and Glabella from the internal carotid artery (ICA), we evaluated changes in cutaneous blood flow using laser speckle contrast imagining (LSCI) as a potential method for indirect real-time monitoring of cerebral perfusion. Nine patients (8 men, mean age 70 years) underwent eversion carotid endarterectomy under local anesthesia. ⋯ The supraorbital cutaneous blood flow did not change significantly following reperfusion of the external carotid artery (ECA) (221 ± 109 to 281 ± 154 AU; p = 0.175) and ICA (281 ± 154 to 310 ± 184 AU; p = 01). A comparable trend for Glabella followed ECA (276 ± 107 to 342 ± 170 AU; p = 0.404) and ICA (342 ± 170 to 352 ± 191 AU; p = 01) reperfusion. In patients undergoing carotid endarterectomy under local anesthesia, LSCI of the supraorbital and Glabella regions reflected clamping of the CCA but did not distinguish reperfusion of the ICA from that of the ECA.
-
J Clin Monit Comput · Dec 2021
ANI and BIS variations in supine and prone position during closed-tracheal suction in sedated and myorelaxed ICU patients with severe COVID-19: A retrospective study.
The purpose of this study was to assess Analgesia/Nociception Index (ANI) and bispectral index (BIS) variations in supine and prone position during closed-tracheal suction in intensive care unit (ICU) patients with severe COVID-19 pneumonia requiring myorelaxation and prone positioning. We retrospectively reviewed the data of 15 patients hospitalized in ICU for severe COVID-19 pneumonia requiring sedation, myorelaxation and prone positioning. The BIS, instant ANI (ANIi), mean ANI (ANIm), heart rate (HR), systolic blood pressure (SBP) and SpO2 were retrieved in supine and prone position 1 min before tracheal suction then every minute from the beginning of tracheal suction during 4 min and compared using ANOVA for repeated measures (p < 0.05 considered as statistically significant). ⋯ The median [Q1-Q3] ANIi value decreased earlier 1 min after the beginning of tracheal suction from 84 [69-98] to 73 [60-90] in supine position and from 84 [60-99] to 71 [51-88] in prone position. Both HR, SBP and SpO2 varied modestly but significantly during tracheal suction with no difference between positions. Monitoring ANI, but not BIS, may be of interest to detect noxious stimuli such as tracheal suction in ICU myorelaxed patients with severe COVID-19 pneumonia requiring prone positioning.
-
J Clin Monit Comput · Dec 2021
Individualized mechanical ventilation in a shared ventilator setting: limits, safety and technical details.
The COVID-19 pandemic has resulted in an increased need for ventilators. The potential to ventilate more than one patient with a single ventilator, a so-called split ventilator setup, provides an emergency solution. Our hypothesis is that ventilation can be individualized by adding a flow restrictor to limit tidal volumes, add PEEP, titrate FiO2 and monitor ventilation. ⋯ FiO2 could be modulated individually between 0.21 and 0.8 by gradually adjusting the additional flow, and minimal affecting FiO2 in the other circuit. Tidal volumes, PEEP and FiO2 can be individualized and monitored in a bench testing of a split ventilator. In vivo research is needed to further explore the clinical limitations and outcomes, making implementation possible as a last resort ventilation strategy.