Journal of Clinical Monitoring and Computing

, Volume 33, Issue 1, pp 25–30 | Cite as

Continuous noninvasive arterial blood pressure monitoring using the vascular unloading technology during complex gastrointestinal endoscopy: a prospective observational study

  • Julia Y. Nicklas
  • David Beckmann
  • Jasper Killat
  • Martin Petzoldt
  • Daniel A. Reuter
  • Thomas Rösch
  • Bernd SaugelEmail author
Original Research


The innovative vascular unloading technology (VUT) allows continuous noninvasive arterial blood pressure (AP) monitoring. We aimed to investigate whether the VUT enables AP changes to be detected earlier compared with intermittent AP monitoring in patients undergoing gastrointestinal endoscopy. In this prospective observational study, we recorded continuous AP measurements with the VUT (CNAP system; CNSystems Medizintechnik AG, Graz, Austria) and intermittent AP measurements with upper arm cuff oscillometry in 90 patients undergoing complex gastrointestinal endoscopy (Department of Interventional Endoscopy at the University Medical Center Hamburg-Eppendorf, Hamburg, Germany). A “hypotensive phase” was defined as a time period of at least 30 s during which ≥ 50% of the VUT-AP values were in a predefined range of hypotension, i.e., AP value a) ≥ 10% below the last oscillometric value and b) ≤ 65 mmHg for mean AP or ≤ 90 mmHg for systolic AP. In the 5-min-interval between two oscillometric measurements, one or more hypotensive phases were detected in 26 patients (29%) for mean AP and in 27 patients (30%) for systolic AP. Hypotensive phases had a mean duration of 195 ± 99 s for mean AP and 197 ± 97 s for systolic AP with a mean procedure duration of 36 (± 21) min. Continuous noninvasive AP monitoring using the VUT enables hypotensive phases to be detected earlier compared with intermittent AP monitoring during complex gastrointestinal endoscopy. These hypotensive phases may be missed or only belatedly recognized with intermittent AP monitoring. Continuous noninvasive AP measurement facilitates detecting hemodynamic instability more rapidly and therefore may improve patient safety.


Hemodynamic monitoring Volume clamp method Hypotension Oscillometry Arterial pressure 


Compliance with ethical standards

Conflict of interest

JYN and BS received refunds of travel expenses from CNSystems Medizintechnik AG (Graz, Austria). BS received honoraria for giving lectures from CNSystems Medizintechnik AG (Graz, Austria). All other authors have no conflict of interest to disclose. CNSystems Medizintechnik AG (Graz, Austria) provided the technical equipment needed for this study. The company was not involved in the study design, in the collection, analysis, and interpretation of data, writing of the manuscript, and in the decision to submit the manuscript for publication.

Ethical approval

This method comparison study was reviewed and approved by the ethics committee (Ethikkomission der Ärztekammer Hamburg, Hamburg, Germany). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.


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Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Anesthesiology, Center of Anesthesiology and Intensive Care MedicineUniversity Medical Center Hamburg-EppendorfHamburgGermany
  2. 2.Department of Anesthesiology and Intensive Care MedicineUniversity Medical Center RostockRostockGermany
  3. 3.Department of Interdisciplinary EndoscopyUniversity Medical Center Hamburg-EppendorfHamburgGermany

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