Non-invasive continuous blood pressure monitoring: a review of current applications
Non-invasive continuous blood pressure monitoring: a review of current applications
Elena Chung1, Guo Chen2, Brenton Alexander1, Maxime Cannesson1()
1. Department of Anesthesiology & Perioperative Care, University of California, Irvine, CA 92868, USA; 2. Department of Anesthesiology and Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu 610041, China
Blood pressure monitoring has come a long way from the initial observations made by Reverend Hales in the 18th century. There are none that deny the importance of monitoring perioperative blood pressure; however, the limited ability of the current prevalent technology (oscillometric blood pressure monitoring) to offer continuous blood pressure measurements leaves room for improvement. Invasive monitoring is able to detect beat-to-beat blood pressure measurement, but the risks inherent to the procedure make it unsuitable for routine use except when this risk is outweighed by the benefits. This review focuses on the discoveries which have led up to the current blood pressure monitoring technologies, and especially the creation of those offering non-invasive but continuous blood pressure monitoring capabilities, including their methods of measurement and limitations.
. Non-invasive continuous blood pressure monitoring: a review of current applications[J]. Frontiers of Medicine, 0, (): 91-101.
Elena Chung, Guo Chen, Brenton Alexander, Maxime Cannesson. Non-invasive continuous blood pressure monitoring: a review of current applications. Front Med, 0, (): 91-101.
Manual auscultatory technique where cuff is inflated and slowly deflated while practitioner listens over brachial artery for Korotkoff sounds (phase I–V)
Clinical “gold standard” for non-invasive monitoringInexpensiveNo risk to patient
Relies on “trained” personnel Subjective method with possible human errorCuff sizing errorCannot be done continuously
Oscillometric
Automated technique where cuff is inflated and slowly deflated while a pressure sensor detects oscillations
ConvenientInexpensiveRequires little to no operator skill
Cuff sizing errorCannot be done continuously
Arterial line
Direct arterial catheterization (radial, femoral, brachial, etc.) connected through a fluid column to a pressure transducer
“Gold standard” for invasive monitoringContinuous monitoring
Risk to the patientRequires “trained” personnel to place appropriately
Pe?ás
Volume clamp method which utilizes a finger cuff that adjusts pressure order to keep optically measured finger vascular volume constant
ConvenientNon-invasiveContinuous monitoring
ExpensiveAffected by factors such as cold extremities, vasopressorsNeeds calibration via another method
Tonometry
Uses applanation (flattening) of the radial artery and measures pressure transmitted through skin
Non-invasiveContinuous monitoring
ExpensiveManual positioning of tonometer over radial artery not always accurate
Pulse transit time (photometric)
Pulse transducers located at two different sites records the time it takes for a arterial wave to travel between these two points
Non-invasiveContinuous monitoringRequires no additional monitors over standard ASA monitors
Not fully developed to correlate pulse transit time to blood pressure
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