Journal of clinical monitoring and computing
-
J Clin Monit Comput · Dec 2013
Comparative Study Observational StudyThe impact of systemic vascular resistance on the accuracy of the FloTrac/Vigileo™ system in the perioperative period of cardiac surgery: a prospective observational comparison study.
FloTrac/Vigileo™ system is based on arterial pressure waveform analysis arterial pressure-based CO (APCO). Therefore, systemic vascular resistance (SVR) can influence the accuracy of APCO. The purpose of this study is to evaluate the relationship between SVR and the accuracy of APCO. ⋯ Subanalysis based on SVR with Lin's concordance correlation coefficient revealed that relatively satisfactory concordance was found in the normal-SVR group (concordance correlation coefficient ρ c = 0.51-0.56) regardless of vasoactive agent use. The accuracy of the FloTrac/Vigileo™ System (v. 3.02) is relatively satisfactory in the condition with normal SVR regardless of vasoactive agent use. Positive correlation between the bias and SVR can be the clue to the more effective use of FloTrac/Vigileo™ system.
-
J Clin Monit Comput · Dec 2013
Validation of the new Complior sensor to record pressure signals non-invasively.
The Complior device (Alam Medical, France) has contributed to the rise of arterial stiffness as a measure of cardiovascular risk. In its latest version (Complior Analyse) the sensor records pressure instead of distension waveforms thus allowing the measurement of central pressure and pulse wave analysis. The aim of our study was to verify that the new sensor measures pressure waveforms accurately in both time and frequency domain. ⋯ These differences were of the same magnitude as the beat-to-beat variation of the form factor (3.3 %) and of the absolute area (3.1 mmHg·s(-1)), respectively. The second systolic peak was detectable in 4 subjects, with no statistical difference between invasive and non-invasive values. The new pressure sensor of the Complior Analyse device recorded pressure waveforms accurately and could be used to perform pressure wave analysis.
-
The aim of the present study was to develop and validate an objective index for nociception level (NoL) of patients under general anesthesia, based on a combination of multiple physiological parameters. Twenty-five patients scheduled for elective surgery were enrolled. For clinical reference of NoL, the combined index of stimulus and analgesia was defined as a composite of the surgical stimulus level and a scaled effect-site concentration of opioid. ⋯ These results demonstrate the superiority of multi-parametric approach over any individual parameter in the evaluation of nociceptive response. In addition, advanced non-linear technique may have an advantage over ordinary linear regression for computing NoL index. Further research will define the usability of the NoL index as a clinical tool to assess the level of nociception during general anesthesia.
-
J Clin Monit Comput · Dec 2013
Case ReportsLeakage of sevoflurane from vaporizer detected by air monitoring system: a case report.
Leakage of inhalational anesthetic gases is an important issue not only to staff health but awareness during general anesthesia. After inhalation of sevoflurane commenced, the audible and visible alarm of our custom-made air monitoring system was activated. The system measured 2-4 ppm of sevoflurane. ⋯ After changing inhalational anesthesia to intravenous anesthesia, the concentration of sevoflurane decreased immediately to zero. The filling level on the vaporizer decreased faster than usual. A thorough check of the vaporizer after surgery identified a worn down seal in the filling device of the vaporizer.
-
J Clin Monit Comput · Dec 2013
The relationship between the area of peripherally-derived pressure volume loops and systemic vascular resistance.
Arterial and photoplethysmographic (PPG) waveforms have been utilized to non-invasively estimate stroke volume from the pulse contour. The ability of these pulse contour devices to accurately predict stroke volume is degraded when afterload changes significantly. There is a need for a non-invasive device capable of identifying when vascular tone has changed. ⋯ There was no meaningful correlation between ΔSVR and either ΔPVA or ΔMAP (based on minute-to-minute changes). Indexed values of PVA are correlated with indexed values of SVR and may serve as a useful monitor for changes in afterload but in their present form do not offer added value above the measurement of MAP. Incorporation of different (e.g. finger, forehead) and redundant (e.g. bilateral) sites may significantly improve the accuracy of this technique.