Comparison of continuous non-invasive finger arterial pressure monitoring with conventional intermittent automated arm arterial pressure measurement in patients under general anaesthesia

Abstract

Background For a majority of patients undergoing anaesthesia for general surgery, mean arterial pressure (MAP) is only measured intermittently by arm cuff oscillometry (MAPiNIAP). In contrast, the Nexfin® device provides continuous non-invasive measurement of MAP (MAP cNIAP) using a finger cuff. We explored the agreement of MAP cNIAP and MAPiNIAP with the gold standard: continuous invasive MAP measurement by placement of a radial artery catheter (MAP invasive). Methods In a total of 120 patients undergoing elective general surgery and clinically requiring MAPinvasive measurement, MAPiNIAP and MAPcNIAP were measured in a 30 min time period at an arbitrary moment during surgery with stable haemodynamics. MAP iNIAP was measured every 5 min. Results Data from 112 patients were analysed. Compared with MAPinvasive, modified Bland-Altman analysis revealed a bias (sd) of 2 (9) mm Hg for MAPcNIAP and -2 (12) mm Hg for MAPiNIAP. Percentage errors for MAPcNIAP and MAP iNIAP were 22% and 32%, respectively. Conclusions In a haemodynamically stable phase in patients undergoing general anaesthesia, the agreement with invasive MAP of continuous non-invasive measurement using a finger cuff was not inferior to the agreement of intermittent arm cuff oscillometry. Continuous measurements using a finger cuff can interchangeably be used as an alternative for intermittent arm cuff oscillometry in haemodynamically stable patients, with the advantage of beat-to-beat haemodynamic monitoring. © 2014 The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved.