ISSN:
1573-2614
Keywords:
Equipment
;
pulse oximeter
;
plethysmograph
;
compliance
;
vascular resistance
Source:
Springer Online Journal Archives 1860-2000
Topics:
Computer Science
,
Medicine
Notes:
Abstract Objective. We report the off-line calculation of the vascular complianceof the finger and suggest the continuous on-line use of this methodology asan aid to monitoring the peripheral vascular resistance. This method consistsof the simultaneous analysis of the waveform signals from the pulse oximetermonitors and the arterial pressure as indicators of “volume” andpressure respectively to continuously calculate the vascular“compliance” (volume change per unit pressure change). This shouldbe seen as a “relative compliance” as the pulse plethysmographsignal is not calibrated. This new methodology allows for continuousmonitoring of peripheral vascular compliance as a beat-to-beat indicator ofperipheral vascular resistance. The vaso-constrictors, phenylephrine andephedrine, were shown to decrease the compliance as predicted. Methods. Thearterial pressure and pulse oximeter waveforms were obtained during routineanesthetic care. The waveforms were collected with a computer data-acquisitionsystem and then analyzed “off-line” as an indirect indicator oftotal vascular tone. Demographic and clinical information including drugadministration were recorded. Results. A case report is presented using thisnew form of analysis. Vascular compliance changes induced by phenylephrine andephedrine were studied. A dose response curve of peripheral vascularcompliance to phenylephrine was generated from these data. Conclusions. Byplotting the pulse oximeter waveforms versus the arterial waveforms, multiplevolume versus pressure (relative compliance) loops were obtained. Analysis ofthese loops may assist in the monitoring of vascular compliance.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007361020825
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