\nThe volume of any organ consists of the tissue volume and the volume of blood that fills the organ. Therefore, the tissue volume is constant, and the blood volume varies according to the phase of cardiac cycle (heart contraction or relaxation). Photoplethysmography is a registration of the tissue optical density. The analyzed area is transilluminated with red and infrared light, which then enters the photoconverter. The wavelength of the emitted light has been selected in such a way that it is absorbed by red blood cells in the arterial blood. Therefore, its intensity depends on the amount of blood in the examined tissue. The registered signal is called a photoplethysmogram, which is interpreted according to certain parameters.<\/p>\n
![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_1-scaled.jpg\")
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WHAT IT IS USED FOR<\/strong><\/span> Photoplethysmography in sports medicine helps to develop an individual training program. It is known that intensive physical activity with increase in muscle volume often leads to the vein overpressure and even vessel rupture. Regular monitoring makes it possible to avoid varicosis (abnormally dilated veins) and related complications.<\/p>\n The method helps to select an individual diet plan, exclude from a diet some food products in case they are contraindicated because of increased blood viscosity and calcium metabolism disorder. In people prone to clot formation (thrombosis), such food like egg yolk, liver, caviar etc. should be excluded from a diet. To prevent calcium depletion, it is necessary to reduce intake of coffee, sugar, palm oil.<\/p>\n Examination by photoplethysmograph is necessary before rehabilitation procedures related to vibration (for instance, vibration platforms) or other exercises that are associated with the high risk of blood clot detachment (such as jumping rope, etc.). The same applies to use of vibration beds and other gadgets and procedures causing vibrations in the body. Blood clots most frequently are formed on the walls of lower limbs. A clot in a vein may detach from its point of origin and travel until it becomes wedged, preventing adequate blood flow in a vessel. Blood clots can be life-threatening, for example, if a pulmonary (lung) embolism occur.<\/p>\n REHABILITATION AFTER COVID-19 ILLNESS<\/strong><\/span> PRINCIPLE OF METHOD<\/strong><\/span> The pulse wave on a photoplethysmogram consists of two components. Anacrotic phase [a] corresponds to the systole (heart contraction) and dicrotic phase [b] corresponds to the diastole (relaxation). The dicrotic peak is formed by the reflection wave, when blood goes to lower limbs and returns to aorta. It is considered that pulse wave rate and duration depend on the cardiac function and its shape and peak height depend on the vessel wall state.<\/p>\n The pulse wave of a healthy person is characterized by relatively steep ascendant part of the curve and a relatively high reflection wave. PHOTOPLETHYSMOGRAM ASSESSMENT<\/strong><\/span> VISUAL EVALUATION OF PHOTOPLETHYSMOGRAM<\/span><\/strong> \u2014 there are additional waves near the top (like a cock’s comb) indicating general and local hemodynamics disorders and a possible thrombus;<\/p>\n – steep ascended slope of a pulse wave, its rapid decline, and a slight dicrotic incisure are the signs of low peripheral resistance and a large stroke volume output, indicating the aortic valve insufficiency;<\/p>\n \u2014 the absent dicrotic wave can be associated with diabetes mellitus, atherosclerosis or hypertensive disease;<\/p>\n \u2014 an increased vessel tone is characterized by a long anacrotic phase of the pulse wave with a flat uneven slope and a small or high dicrotic wave, which can indicate the beginning of atherosclerosis or high blood pressure.<\/p>\n First three signs are considered to be the most important. Besides, other signs can be on a photoplethysmogram in different diseases: HOW THE PROCEDURE IS PERFORMED<\/strong><\/span> The sensor is placed on the left index finger in such a way as to put a red line emitting diode (inside the sensor) above the nail. During the 30 seconds procedure it is necessary to avoid movements of this hand not to confound data results due to muscle contraction.<\/p>\n After procedure completion, select the sequence of the most typical pulse waves using a mouse. The software detects control points automatically, but selection by the program can be incorrect due to the unclear shape of a pulse wave. In that case, mark the end of the anacrotic wave and the beginning of the dicrotic wave manually, dragging markers of control points with the mouse.<\/p>\n CONTRAINDICATIONS<\/strong><\/span> It is advisable not to take any medications and avoid any physiotherapy procedures within 24 hours before examination (if it is not a monitoring of treatment or rehabilitation efficacy).<\/p>\n To avoid vessel reaction to the heat or cold, the room temperature should be maintained within +19\u201323\u00b0\u0421. You should note that the arteriolospasm occurs at temperature below 16\u00b0\u0421.<\/p>\n Before the procedure it is recommended that an examined person stays in a comfortable sitting or lying position for several minutes. During measurements pulseoximeter sensor shall be protected from the bright artificial light and direct sunlight.<\/p>\n","protected":false},"excerpt":{"rendered":" Long and active life largely depends on blood vessel state. Vessel disorders are the reason of the most of severe complications, and vice versa: all disorders impact the microcirculation, i. e. capillary net, which consists of the smallest blood vessels. In that case, transport of body fluids in tissues deteriorates. These problems affect the pulse […]<\/p>\n","protected":false},"author":3,"featured_media":0,"parent":1462,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"templ.php","meta":[],"_links":{"self":[{"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/pages\/1270"}],"collection":[{"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/comments?post=1270"}],"version-history":[{"count":17,"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/pages\/1270\/revisions"}],"predecessor-version":[{"id":2225,"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/pages\/1270\/revisions\/2225"}],"up":[{"embeddable":true,"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/pages\/1462"}],"wp:attachment":[{"href":"https:\/\/bioscaner.com\/en\/wp-json\/wp\/v2\/media?parent=1270"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nPhotoplethysmography helps to detect vessel changes in diabetes mellitus, atherosclerosis, hypertensive disease. Besides, it is possible to assess the efficacy of treatment or wellness procedures from improving of vessel state. It also enables to reveal complications of diseases. In particular, this method helps to detect vessel changes in people after COVID-19.<\/p>\n
\nPhotoplethysmogram assessment is particularly important for rehabilitation of patients after coronavirus infection. It is known that one of main complications of viral pneumonia associated with COVID-19 is the increased blood viscosity which can lead to thrombosis, myocarditis, arterial hypertension and other cardiovascular disorders.
\nBased on values of stiffness index and wave reflection index, procedures are assigned as well as the vessel state during the rehabilitation process is monitored.<\/p>\n
\nThe pulse wave forms due to the blood output from the left ventricle during heart contraction. A pressure spreads through the aorta and arteries. The pulse wave velocity through vessels depends on lumen width, vessel wall elasticity, thickness of the vessel wall and the heart muscle strength. Photoplethysmography helps to reveal the signs of stenosis (narrowing of the blood vessel) and sclerosis, assess the vascular tone and the heart function.<\/p>\n
\nThe arteriostenosis leads to the flattening of the ascendant part, lengthening of dicrotic phase duration and decreasing of reflection wave height. There is no reflection wave in significant stenosis.<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_2.png\")
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\nPhotoplethysmogram is assessed by several parameters. The most important parameters are stiffness index and wave reflection index. The stiffness index helps to detect stenosis of large arteries, assess their wall elasticity and indirectly evaluate the calcium metabolism (the higher the stiffness, the more the blood calcium level). The wave reflection index mainly gives information about the tone of arterioles and small vessels. The increased wave reflection index mostly indicates the increased blood viscosity, that can be an indirect evidence of atherosclerosis plaques.<\/p>\n
\nThe main signs of the hemodynamics disorders, which can be seen on the pulse wave, are as follows:<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_3.png\")
<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_4.png\")
<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_5.png\")
<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_6.png\")
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\n– in obliterating endarteritis, a pulse wave amplitude is low in every finger of affected limb;
\n– there is a growing number of reactions indicating the vasodilation in periods of sudden change in weather conditions and geomagnetic storms, especially in people suffering from rheumatism.<\/p>\n![\"PHOTOPLETHYSMOGRAPHY:](\"\/wp-content\/uploads\/2020\/11\/of_7-scaled.jpg\")
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\nConnect Bioscanner to a laptop or a computer to perform photoplethysmography. An electric shock hazard is excluded, because the device is supplied by USB port. Measurements are performed in a contactless way by determining the optical absorbance of the capillary blood components in red and infrared ranges.<\/p>\n
\nPhotoplethysmography is a safe and painless procedure. There are no contraindications, but a finger on which a sensor is placed must be without skin damage.<\/p>\n