Technical issues related to the long-term monitoring of blood flow at different depths using LDF and PPG

The aim of this study was to evaluate an integrated probe using LDF and multiple PPG, for the long-term aspects of skin temperature and blood flow variations at different tissue depths, and especially to investigate whether the presence of the probe affects the temperature. Measurements of temperature and blood flow were performed over 60 min on the lower back of ten subjects, lying on a mattress. The surface temperature of the skin was also measured before and after the 60 min period, and repeated with three probe configurations with the probe switched on, turned off and in the absence of a probe. A general increase in the blood flow was found to occur during the 60 min interval at all depths reached by this probe, but with variations over time. No difference was found in temperatures recorded for the different probe configurations. According to our measurements, the presence of the probe does not affect the skin surface temperature at 60 min. Our investigation shows that skin temperature can be expected to increase and approach the body core temperature by just lying in supine position on the mattress. The increase in temperature and blood flow that is known to occur, possibly attributable to pressure-induced vasodilatation, must be taken into consideration when performing these kinds of measurements.

[1]  Sara Bergstrand,et al.  Blood flow measurements at different depths using photoplethysmography and laser Doppler techniques , 2009, Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging.

[2]  J. Hales,et al.  Evidence for skin microvascular compartmentalization by laser-Doppler and photoplethysmographic techniques. , 1993, International journal of microcirculation, clinical and experimental.

[3]  G Gustavsson,et al.  Skin blood flow in relation to external pressure and temperature in the supine position on a standard hospital mattress. , 2020, Scandinavian journal of rehabilitation medicine.

[4]  Pierre Abraham,et al.  Early decrease of skin blood flow in response to locally applied pressure in diabetic subjects. , 2002, Diabetes.

[5]  P. Oberg,et al.  Photoplethysmography. Part 1. Comparison with laser Doppler flowmetry. , 1991, Medical & biological engineering & computing.

[6]  M. Clark,et al.  Pressure ulcer prevalence in Europe: a pilot study. , 2007, Journal of evaluation in clinical practice.

[7]  J L Saumet,et al.  Dynamics of local pressure-induced cutaneous vasodilation in the human hand. , 2001, Microvascular research.

[8]  R. Maniewski,et al.  Multichannel laser-Doppler probe for blood perfusion measurements with depth discrimination , 1998, Medical and Biological Engineering and Computing.

[9]  Maria Lindén,et al.  A technique based on laser Doppler flowmetry and photoplethysmography for simultaneously monitoring blood flow at different tissue depths , 2010, Medical & Biological Engineering & Computing.

[10]  Karin Wårdell,et al.  Laser Doppler Perfusion Monitoring and Imaging. Biomedical Photonics Handbook , 2003 .

[11]  D. Ubbink,et al.  Red and green laser Doppler compared with capillary microscopy to assess skin microcirculation in the feet of healthy subjects. , 1999, Microvascular research.

[12]  John Allen Photoplethysmography and its application in clinical physiological measurement , 2007, Physiological measurement.

[13]  J. Posnett,et al.  The cost of pressure ulcers in the UK. , 2004, Age and ageing.

[14]  Gert E. Nilsson,et al.  Evaluation of a Laser Doppler Flowmeter for Measurement of Tissue Blood Flow , 1980, IEEE Transactions on Biomedical Engineering.

[15]  Karin Wårdell,et al.  Laser Doppler perfusion,monitoring and imaging , 2003 .

[16]  J. Spigulis,et al.  Multilaser photoplethysmography technique , 2008, Lasers in Medical Science.

[17]  J. Donofrio,et al.  Skin perfusion responses to surface pressure-induced ischemia: implication for the developing pressure ulcer. , 1999, Journal of rehabilitation research and development.

[18]  G. Holloway,et al.  Laser Doppler measurement of cutaneous blood flow. , 1977, The Journal of investigative dermatology.

[19]  Ingemar Fredriksson,et al.  Measurement depth and volume in laser Doppler flowmetry. , 2009, Microvascular research.

[20]  Maria Lindén,et al.  Evaluation of antidecubitus mattresses , 2005, Medical and Biological Engineering and Computing.

[21]  Gert E. Nilsson,et al.  A New Instrument for Continuous Measurement of Tissue Blood Flow by Light Beating Spectroscopy , 1980, IEEE Transactions on Biomedical Engineering.

[22]  B. Gerdle,et al.  Non-invasive monitoring of muscle blood perfusion by photoplethysmography: evaluation of a new application. , 2005, Acta physiologica Scandinavica.