title: Comparison of non-invasive blood pressure monitoring using modified arterial applanation tonometry with intra-arterial measurement.
abstract: Intermittent non-invasive blood pressure measurement with tourniquets is slow, can cause nerve and skin damage, and interferes with other measurements. Invasive measurement cannot be safely used in all conditions. Modified arterial tonometry may be an alternative for fast and continuous measurement. Our aim was to compare arterial tonometry sensor (BPro®) with invasive blood pressure measurement to clarify whether it could be utilized in the postoperative setting. 28 patients who underwent elective surgery requiring arterial cannulation were analyzed. Patients were monitored post-operatively for 2 h with standard invasive monitoring and with a study device comprising an arterial tonometry sensor (BPro®) added with a three-dimensional accelerometer to investigate the potential impact of movement. Recordings were collected electronically. The results revealed inaccurate readings in method comparison between the devices based on recommendations by Association for the Advancement of Medical Instrumentation (AAMI). On a Bland-Altman plot, the bias and precision between these two methods was 19.8 ± 16.7 (Limits of agreement - 20.1 to 59.6) mmHg, Spearman correlation coefficient r = 0.61. For diastolic pressure, the difference was 4.8 ± 7.7 (LoA - 14.1 to 23.6) mmHg (r = 0.72), and for mean arterial pressure it was 11.18 ± 11.1 (LoA - 12.1 to 34.2) mmHg (r = 0.642). Our study revealed inaccurate agreement (AAMI) between the two methods when measuring systolic and mean blood pressures during post-operative care. The readings for diastolic pressures were inside the limits recommended by AAMI. Movement increased the failure rate significantly (p < 0.001). Thus, arterial tonometry is not an appropriate replacement for invasive blood pressure measurement in these patients.
authors.affiliation: Department of Anaesthesia, Tampere University Hospital, PL2000, 33521, Tampere, Finland. Jarkko.harju@fimnet.fi.
authors.forename: Jarkko
authors.initials: J
authors.lastname: Harju
authors.affiliation: Tampere University of Technology, Tampere, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Vehkaoja
authors.affiliation: Tampere University of Technology, Tampere, Finland.
authors.forename: Pekka
authors.initials: P
authors.lastname: Kumpulainen
authors.affiliation: CamsoS Consulting Ltd., Helsinki, Finland.
authors.forename: Stefano
authors.initials: S
authors.lastname: Campadello
authors.affiliation: Medical School, University of Tampere, Tampere, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Lindroos
authors.affiliation: Department of Anaesthesia, Tampere University Hospital, PL2000, 33521, Tampere, Finland.|Medical School, University of Tampere, Tampere, Finland.
authors.forename: Arvi
authors.initials: A
authors.lastname: Yli-Hankala
authors.affiliation: Medical School, University of Tampere, Tampere, Finland.|Department of Surgery, Tampere University Hospital, Tampere, Finland.
authors.forename: Niku
authors.initials: N
authors.lastname: Oksala
mesh_terms: D000054:Acceleration; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D062186:Arterial Pressure; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000379:methods*; D015924:Blood Pressure Monitors; D003422:Critical Care / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods*; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D011184:Postoperative Period; D017534:Radial Artery / Q000502:physiology*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted
keywords: Arterial pressure; Blood pressure monitors; Monitoring, intraoperative