Comparing the effects of human hind limb massage by analysis of Laser Doppler Flowmetry and Photoplethysmography signal components using the wavelet transform

Abstract

Biomedical and Biopharmaceutical Research J o r n a l d e I n v e s t i g a ç ã o B i o m é d i c a e B i o f a r m a c ê u t i c a 70 Comparing the effects of human hind limb massage by analysis of Laser Doppler Flowmetry and Photoplethysmography signal components using the wavelet transformComparando os efeitos da massagem no membro inferior humano através da análise dos componentes dos sinais de Fluxometria de Laser Doppler e de Fotopletismografia utilizando a transformada de wavelet Abstract Non-invasive optical techniques, such as LDF (laser Doppler flowmetry) and PPG (photoplethysmography) are leading technologies to assess the human microcirculation. New mathematical strategies for signal processing such as WT (wavelet transform) have been developed to enhance its quantification capabilities. We have dedicated some effort to better understand the impact of massage therapy, a non-conventional technique used to relieve symptoms of vascular failure and improve functions, using these instruments. A group of 24 young healthy volunteers (19.9 ± 1.7 years old), both sexes, was submitted to two massage protocols applied in one limb, the other serving as control. Each protocol included three phases -rest (I), massage (II), and recovery (III). LDF and PPG signals were obtained from both limbs and analyzed with the WT (p<0.05). A regional circulatory adaptation seems to take place during massage manoeuvres, affecting both test and control limbs detected with LDF and PPG. Some differences are noted regarding their oscillatory components, being clear that both sympathetic and myogenic components play a central role in the process. It is also clear that the simultaneous use of these two technologies seems to provide more detail and sensitivity in the analysis of the phenomena involved. ResumoTécnicas óticas não invasivas, como o FLD (fluxometria por laser Doppler) e a FPG (fotopletismografia), vêm sendo utilizadas na avaliação da microcirculação em humanos. Novas estratégias matemáticas para processamento de sinais, como a TO (transformada de ondeleta), foram desenvolvidas para melhorar as suas capacidades de quantificação. Temos desenvolvido vários esforços para entender melhor o impacto da massagem, uma técnica não convencional usada para aliviar os sintomas de disfunção vascular, e melhorar a função, usando estes instrumentos. Um grupo de 24 jovens voluntários saudáveis (19.9 ± 1.7 anos), de ambos os sexos, foi submetido a dois protocolos de massagem aplicados em um dos membros, servindo o outro como controlo. Cada protocolo incluiu três fases -I descanso, II massagem e III recuperação. Foram obtidos sinais de LDF e PPG de ambos os membros e analisados com a TO (p <0.05). Uma adaptação circulatória regional detetada com LDF e PPG ocorre durante as manobras de massagem , afetando ambos os membros. Algumas diferenças foram observadas em relação aos seus componentes oscilatórios, onde os componentes simpáticos e miogénicos parecem desempenhar um papel principal. Também está claro que o uso simultâneo dessas duas tecnolo...

Exploring the perfusion modifications occurring with massage in the human lower limbs by non-contact polarized spectroscopy

“…Mais recentemente, tam-culatory homeostasis likely involving some cross-talk between local neurogenic and myogenic mechanisms central components via sympathetic efferents. Recently we found that massage in one inferior limb could induce a similar circulatory adaptation interfering with the circulatory homeostasis of both limbs 15 , confirming the same type of cooperation phenomena between limbs described previously. All these observations were obtained with non-invasive techniques, namely laser doppler flowmetry (LDF) and photopletismography (PPG), well known and experimented techniques, although not exempt from criticism and concerns 4,12,16 .…”

“…Em ambos os casos esta cooperação parece revelar outros intervenientes na homeostase circulatória na zona distal do membro, envolvendo provavelmente alguma comunicação entre os componentes centrais dos mecanismos neurogénicos e miogénicos locais, através de eferentes simpáticos. Recentemente, descobrimos que a massagem, efetuado num membro inferior, podia induzir uma adaptação circulatória similar, interferindo com a homeostase circulatória de ambos os membros 15 , confirmando o mesmo tipo de fenómeno de cooperação entre membros descrito acima. Todas estas observações foram obtidas com técnicas não invasivas, nomeadamente fluxometria por laser Doppler (FLD) e fotopletismografia (FPG), técnicas bem conhecidas e testadas, mas não isentas de críticas e preocupações 4,12,16 .…”

The Venoarteriolar Reflex Significantly Reduces Contralateral Perfusion as Part of the Lower Limb Circulatory Homeostasis in vivo

“…Nevertheless, this common perfusion response registered in both limbs, and in particular, in the resting foot after evoking the VAR in the opposite foot does suggest a centrally-mediated neurogenic response. Recent studies applying this methodology, reported similar phenomena in human (Rocha et al, 2017 , 2018 ) as in mice (Monteiro Rodrigues et al, 2018 ). Although we cannot conclude that this response is adrenergic in nature or not, it is likely evoked by the abruptly intense myogenic and endothelial cooperation registered in the depending limb and is a response to regulate the regional circulation physiology.…”

Lower Limb Perfusion Asymmetries in Humans at Rest and Following Activity—A Collective View

“…Data were collected from participants included in previous studies regarding perfusion of the human lower limb, sharing specific predefined inclusion/non-inclusion criteria [33][34][35][36][37][38][39][40]. Participants were all non-athletes reporting regularly low physical activity and absence of any metabolic disease (diabetes, dyslipidaemia).…”

“…We have detected baseline perfusion asymmetries in healthy participants, of both sexes and different ages, submitted to different procedures meant to (temporarily) modify peripheral perfusion in the lower limb. From massage [33][34][35] to the venoarteriolar reflex [36], plantar flexion [37], unipodal squat/hemisquat, and walking [38,39], we were able to identify and follow each hemodynamical adaptive process impacting not only local perfusion but also systemic hemodynamics in humans as in mice [36,40]. Therefore, the aim of the present analysis was to collectively assess the association of sex, age, and body mass index (BMI) with perfusion asymmetries at rest and in the recovery period after a controlled challenge from the studies published previously by our group (Table 1).…”