title: Determination of saturation, heart rate, and respiratory rate at forearm using a Nellcor™ forehead SpO2-saturation sensor.
abstract: Alterations in arterial blood oxygen saturation, heart rate (HR), and respiratory rate (RR) are strongly associated with intra-hospital cardiac arrests and resuscitations. A wireless, easy-to-use, and comfortable method for monitoring these important clinical signs would be highly useful. We investigated whether the Nellcor™ OxiMask MAX-FAST forehead sensor could provide data for vital sign measurements when located at the distal forearm instead of its intended location at the forehead to provide improved comfortability and easy placement. In a prospective setting, we recruited 30 patients undergoing surgery requiring postoperative care. At the postoperative care unit, patients were monitored for two hours using a standard patient monitor and with a study device equipped with a Nellcor™ Forehead SpO2sensor. The readings were electronically recorded and compared in post hoc analysis using Bland-Altman plots, Spearman's correlation, and root-mean-square error (RMSE). Bland-Altman plot showed that saturation (SpO2) differed by a mean of -0.2 % points (SD, 4.6), with a patient-weighted Spearman's correlation (r) of 0.142, and an RMSE of 4.2 points. For HR measurements, the mean difference was 0.6 bpm (SD, 2.5), r = 0.997, and RMSE = 1.8. For RR, the mean difference was -0.5 1/min (4.1), r = 0.586, and RMSE = 4.0. The SpO2readings showed a low mean difference, but also a low correlation and high RMSE, indicating that the Nellcor™ saturation sensor cannot reliably assess oxygen saturation at the forearm when compared to finger PPG measurements.
authors.affiliation: Department of Anesthesia, 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: Medical School, University of Tampere, Tampere, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Lindroos
authors.affiliation: Tampere University of Technology, Tampere, Finland.
authors.forename: Pekka
authors.initials: P
authors.lastname: Kumpulainen
authors.affiliation: Department of Anesthesia, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Sasu
authors.initials: S
authors.lastname: Liuhanen
authors.affiliation: Department of Anesthesia, 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: D000368:Aged; D001785:Blood Gas Monitoring, Transcutaneous / Q000379:methods; D005260:Female; D005385:Fingers; D005542:Forearm; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010092:Oximetry / Q000379:methods*; D010100:Oxygen / Q000097:blood*; D011446:Prospective Studies; D015203:Reproducibility of Results; D056152:Respiratory Rate
chemical_list: D010100:Oxygen
keywords: Heart rate; Intraoperative monitoring; Plethysmography; Pulse oximetry; Respiratory rate