Comparing volume-clamp method and intra-arterial blood pressure measurements in patients with atrial fibrillation admitted to the intensive or medium care unit

G F N Berkelmans,B E Westerhof,Y M Smulders,A M E Spoelstra-De Man,S Kuipers

doi:10.1007/s10877-017-0044-9

Abstract

International guidelines highlight the importance of blood pressure (BP) in patients with atrial fibrillation (AF). However, BP measurement in AF is complicated by beat-to-beat fluctuation. Automated BP measurement devices are not validated for patients with AF and no consensus exists on how to measure BP in AF manually. Beat-to-beat BP measurement using the volume-clamp method (VCM) could represent a non-invasive method to accurately assess BP, but has not been validated in AF. 31 admitted patients with sustained AF and 10 control patients with sinus rhythm underwent simultaneous intra-arterial and non-invasive BP measurement using a VCM monitor (Nexfin®, BMEYE, Amsterdam, The Netherlands). Patients with compromised peripheral perfusion, high doses of vasopressor drugs or peripheral edema were excluded. Differences in systolic, diastolic and mean BP of 5 (standard deviation; SD 8) mmHg (accuracy and precision) between both methods were considered acceptable. Additionally, the magnitude of beat-to-beat fluctuations in systolic BP of both methods was compared. In AF, the differences between noninvasive and invasive BP were −4 (SD 12), +1 (SD 7) and 0 (SD 8) mmHg for systolic, diastolic and mean BP respectively. Absolute differences in beat-to-beat BP fluctuations were 1.5 (IQR 0.8–3.8) mmHg. Accuracy of VCM in AF was similar to sinus rhythm. In conclusion, in patients with AF, accurate and precise measurement of non-invasive beat-to-beat BP measurement using the VCM is possible, the one exception being the precision of systolic BP. Beat-to-beat variability can be accurately reproduced.

Highlights

Atrial fibrillation (AF) is the most common arrhythmia with an incidence of 60 per 100,000 person-years in women and 78 per 100,000 person-years in men
Most patients were post-operative after cardiac surgery or carotid endarterectomy, others were recovering from sepsis or respiratory failure
The most important finding in this study is that the noninvasive volume-clamp method (VCM) method is accurate in measuring beat-tobeat blood pressure (BP) in patients with AF

Summary

Introduction

Atrial fibrillation (AF) is the most common arrhythmia with an incidence of 60 per 100,000 person-years in women and 78 per 100,000 person-years in men. The prevalence increases with age from 0.1% among adults younger than 55 years to 9.0% in persons aged 80 years or older [1] and the life-time risk of AF is ~16%. AF is associated with an increased risk of death and cardiovascular disease [2]. Reduction of cardiovascular risk has priority in patients with AF. Elevated blood pressure (BP) is the leading risk factor for death and disability-adjusted life-years lost [3], but is an important risk factor for AF [4].

Methods

Results

Conclusion