Normalized pulse volume (NPV) derived photo-plethysmographically as a more valid measure of the finger vascular tone

Park

Jang

et al. 2009

Med Biol Eng Comput

Abstract:The purpose of the present study was to evaluate the use of salivary Chromogranin-A (CgA), which is already used in general as a mental stress marker, for studying the stressful situation created by simulated monotonous driving. After informed consent 25 healthy male & female subjects were studied, under constant environment-controlled conditions. We measured the following physiological variables: blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR), normalized pulse volume (NPV) as an index of alpha-adrenergic sympathetic activity to the finger arteriolar vessels, levels of cortisol and CgA during monotonous driving. The induced stress led to the expected decreases in NPV and increases in TPR and BP caused by peripherally-related sympathetic acceleration. However, CgA levels were found to fall gradually in accordance with the gradual increase of subjective rating of stress (SRS) and significantly (p<0.01) decreased over the period of the simulated monotonous driving.Our hypothesis for the gradual decrease of CgA levels during the simulated monotonous driving is as follows. CgA, catestatin and Catecholamines are co-released into the extra-cellular environment. Peripheral sympathetic activity was accelerated by stress resulting from the simulated monotonous driving. Upon peripheral vessel constriction, an increase in total peripheral resistance (TPR) then increased BP which, in turn, activated catestatin. Consequently, secretion of CgA was blocked by the co-secreted catestatin from chromaffin granules. The results obtained strongly indicate that, although CgA has been reported as a possible marker of stress, CgA levels are not increased in the stressful situation of simulated monotonous driving.

Section: Methodsmentioning

confidence: 99%

Relationship between salivary Chromogranin-A and stress induced by simulated monotonous driving

Park

Jang

et al. 2009

Med Biol Eng Comput

“…Mobile health Heart rate (HR) and pulse volume (PV) are frequently used physiological measures in a wide range of psychological studies. Examples include studies of mental stress, health, mental disorders, emotion, and memory (e.g., Hamer, Tanaka, Okamura, Tsuda, & Steptoe, 2007;Matsumura, Yamakoshi, Noguchi, Rolfe, & Matsuoka, 2012;McNally et al, 2004;Sawada, Tanaka, & Yamakoshi, 2001). …”

mentioning

confidence: 99%

iPhysioMeter: A new approach for measuring heart rate and normalized pulse volume using only a smartphone

Matsumura

2013

Behav Res

Heart rate (HR) and normalized pulse volume (NPV) are physiological indices that have been used in a diversity of psychological studies. However, measuring these indices often requires laborious processes. We therefore developed a new smartphone program, named iPhysioMeter, that makes it possible to measure beat-bybeat HR and ln NPV using only a smartphone. We examined its accuracy against conventional laboratory measures. Mental stress tasks were used to alter HR and ln NPV in 12 participants. Bland-Altman analyses revealed negligible proportional bias for HR and ln NPV or for their change values, expressed as ΔHR and Δln NPV. However, a relatively large fixed bias did emerge for ln NPV, as well as a small one for Δln NPV, although both were within the limits of agreement. These findings suggest that iPhysioMeter can yield valid measures of the absolute level of HR and of relative changes in ln NPV.

“…Normalized pulse volume (NPV), shown to be a valid index of α-adrenalin-mediated sympathetic activity [18], [24], was calculated on a beat-by-beat basis by dividing the PG ac by PG dc on the condition that the counter-pressure is constant [17], [18], [24], giving the following equation:…”

Section: B Measurement Principlementioning

confidence: 99%

“…Briefly, measurements are taken from a single finger, using photo-plethysmography for the detection of peripheral pulse volume signals. The instrument then calculates: 1) systolic, mean and diastolic blood pressure (SBP, MBP and DBP, respectively) using the volume-oscillometric method [13] - [15]; 2) pulse pressure (PP), which is a strong predictor of increased large artery stiffness and high cardiovascular risk [16]; 3) heart rate (HR); 4) normalized pulse volume (NPV), which reflects !-adrenalin-mediated sympathetic control of the finger arteriolar vessels [17], [18]; and 5) the finger-artery elasticity index (FEI) derived from a simple descriptive model of the exponential pressure-volume function for the finger vascular bed [17], [19], modified by the volume elastic modulus [20]. These cardiovascular indices are simultaneously obtained using the present instrument and, whilst each is of interest and significant in itself, the adoption of a comprehensive method for handling the combined datasets is necessary if they are to be of practical use.…”

Section: Introductionmentioning

confidence: 99%

Potential for Health Screening Using Long-Term Cardiovascular Parameters Measured by Finger Volume-Oscillometry: Pilot Comparative Evaluation in Regular and Sleep-Deprived Activities

IEEE J. Biomed. Health Inform.

Matsumura

Rolfe³

et al. 2014

Self Cite

Abstract-We explored the potential of health screening based on the long-term measurement of cardiovascular parameters using the finger volume-oscillometric technique. An automated instrument made simultaneous measurements of key cardiovascular parameters, including blood pressure, pulse pressure, heart rate, normalized pulse volume as an index of α-adrenalin-mediated sympathetic activity, and finger arterial elasticity. These were derived from finger photoplethysmographic signals during application of cuff pressure. To assess the feasibility of achieving a screening function, measurements were made in ten healthy volunteers during 10 days of day-to-day living (normal condition), and carried out several times at a fixed time every day. During successive 10-day measurements, a 30-hour period of total sleep deprivation was introduced as a physiological challenge (abnormal condition). A linear discriminant analysis of the data was conducted to determine whether these two conditions could be discriminated. Periodic data collection was performed rapidly and easily, and the %-correct classifications of normal and abnormal conditions T. Yamakoshi is with the School of Mechanical Engineering, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192 Japan (e-mail: takey@staff.kanazawa-u.ac.jp).K. Matsumura and K. Yamakoshi are with the School of Mechanical Engineering, College of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192 Japan (e-mail: kenta16moon @se.kanazawa-u.ac.jp; kyama@staff.kanazawa-u.ac.jp).P. Rolfe is with the Oxford BioHorizons Ltd., 31-33 Albion Place, Maidstone ME14 5DZ UK and the Department of Automatic Measurement and Control, Harbin Institute of Technology, 92 West Dazhi Street, Nan Gang District, Harbin 150001 China (e-mail: PeterRolfe@aol.com).S. Hanaki and J. Lee are with the Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192 Japan (e-mail: shanaki@gmail.com; jihyoung@stu.kanazawa-u.ac. jp).A. Ikarashi is with the Department of Medical Engineering, Aino University, 4-5-4 Higashioota, Ibaraki-shi, Osaka 567-0012 Japan (e-mail: a-ikarashi@me-u.aino.ac.jp).were 78.2% and 77.5%, respectively. This ability of the method to discriminate between regular and sleep-deprived activities demonstrates its potential for healthcare screening during day-to-day living. Further investigations using larger age and gender groups of subjects including patients with cardiovascular diseases under real-life situations are required.Index Terms-blood pressure, finger-artery elasticity index, pulse pressure, heart rate, normalized pulse volume, healthcare.