Journal of clinical monitoring and computing
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J Clin Monit Comput · Jun 2015
Trending ability and limitations of transpulmonary thermodilution and pulse contour cardiac output measurement in cats as a model for pediatric patients.
The present study evaluated transpulmonary thermodilution (TPTD) and pulse contour cardiac output (PCCO) both measured by the PiCCO Plus™ monitor (Pulsion Medical Systems, Munich, Germany) against pulmonary artery thermodilution (PATD) in cats as a hemodynamic model for small children. A wide range of cardiac outputs (CO) was simultaneously measured. Accuracy and trending abilities were critically evaluated. ⋯ Both tested methods constantly overestimated simultaneous PATD measurements. The small size, low flows and the relative short catheter not reaching the abdominal aorta may explain that. However TPTD tracked changes accurately opposed to a poor trending ability of the PCCO measurement.
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J Clin Monit Comput · Jun 2015
Increasing signal processing sophistication in the calculation of the respiratory modulation of the photoplethysmogram (DPOP).
DPOP (∆POP or Delta-POP) is a non-invasive parameter which measures the strength of respiratory modulations present in the pulse oximetry photoplethysmogram (pleth) waveform. It has been proposed as a non-invasive surrogate parameter for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. Many groups have reported on the DPOP parameter and its correlation with PPV using various semi-automated algorithmic implementations. ⋯ Through increasingly advanced pre-processing and post-processing enhancements to the algorithm, the correlation coefficient between DPOP and PPV improved from a baseline value of R = 0.347 to R = 0.852 for the stable data set, and, correspondingly, R = 0.225 to R = 0.728 for the more challenging global data set. Marked gains in algorithm performance are achievable for manually selected stable regions of the signals using relatively simple algorithm enhancements. Significant additional algorithm enhancements, including a correction for low perfusion values, were required before similar gains were realised for the more challenging global data set.
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J Clin Monit Comput · Jun 2015
The ability of the Vigileo-FloTrac system to measure cardiac output and track cardiac output changes during one-lung ventilation.
This study was aimed at comparing the cardiac output (CO) measured by the Vigileo™-FloTrac™ system with that estimated by the thermodilution pulmonary artery catheter (PAC) during one-lung ventilation (OLV) and determining the reliability of this system in tracking phenylephrine-induced CO changes during OLV. Sixteen patients scheduled for descending aorta replacement were enrolled. The study was performed 30 min after starting OLV under stable hemodynamic conditions. ⋯ Four-quadrant plot analysis showed a concordance rate of 24.7 %, while polar plot analysis showed that the concordance rate was 13.3 %; the angular bias, -45.9°; radial limit of agreement, 85.3°. The bias between APCO and ICO was significantly correlated with the SVRI value (p < 0.001, r(2) = 0.822). The reliability of the Vigileo™-FloTrac™ system during OLV to estimate CO and track phenylephrine-induced CO changes was not acceptable.