AUTHOR=Kiviniemi Antti M. , Hintsala Heidi , Hautala Arto J. , Ikäheimo Tiina M. , Jaakkola Jouni J. , Tiinanen Suvi , Seppänen Tapio , Tulppo Mikko P. TITLE=Impact and management of physiological calibration in spectral analysis of blood pressure variability JOURNAL=Frontiers in Physiology VOLUME=5 YEAR=2014 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2014.00473 DOI=10.3389/fphys.2014.00473 ISSN=1664-042X ABSTRACT=

Physiological calibration (Physiocal) improves the quality of continuous blood pressure (BP) signal from finger. However, the effects of Physiocal on spectral characteristics of systolic BP (SBP) variability are not well-known. We tested the hypothesis that the use of Physiocal may alter the results on SBP variability when compared with BP recording without Physiocal. Continuous BP was recorded simultaneously from fingers of both arms during 10-min standing by two Nexfin devices, one with (ON) and the other without (OFF) Physiocal (n = 19). Missing SBP values in ON signal were linearly interpolated over Physiocal sequences (ONinter). The OFF signal was analyzed without any corrections (OFFreference) and after linear interpolation of corresponding sequences when Physiocal appeared in the ON signal (OFFinter). Mean low frequency power of SBP oscillations (LFSBP, 0.04–0.15 Hz) did not differ between the OFFreference, OFFinter, and ONinter. However, LFSBP deviated more from OFFreference when analyzed from ONinter compared with the analysis from OFFinter [median (interquartile range): 14.7 (4.6–38.6) vs. 0.9 (0.5–1.8) %, p < 0.05]. In conclusion, the use of Physiocal had a significant effect on the spectral SBP variability that overwhelms the impact of linear interpolation of short data sequences. Therefore, caution is needed when comparing SBP variability between BP datasets acquired with and without Physiocal.