By : Dr. Franyi Sarmiento, Ph.D., Inspenet, March 22, 2022.
The shifts and work modalities in the Chilean mining companies that are located at high altitudes are varied. Sometimes it is ‘4×3’, that is, four days working and sleeping on the job, and three days off, or ‘7×7’, among others. The coming and going, the variation in height and exposure to land that is over 2,500 meters above sea level (masl) generate certain changes in the body, specifically in the heart muscle and arteries.
That is why Claudio García, researcher at the Millennium Cardio MR Nucleus and director of the Department of Mechanical Engineering at the University of Santiago, conducts research to determine how changes in altitude affect the biomechanics of the cardiovascular system.
First it is necessary to explain what is the influence of height on our body. Let us remember that the air we breathe has in its composition 21 percent oxygen, 79 percent nitrogen, and traces of other gases.
That composition is constant throughout the atmosphere, both at sea level and at the top of Mount Everest. However, in places like Calama, San Pedro de Atacama, Putre and others, we feel that “air is missing”. “This is because at higher altitudes there is lower atmospheric pressure, and therefore lower partial pressure of oxygen, which gives us the feeling of shortness of breath,” explained Marcelo Andía, alternate director of the Milenio Cardio MR Nucleus.
This study is characterized by being an interdisciplinary incursion between engineering, and its ability to carry out biomechanical studies at the service of Medicine. In Chile, different health researchers previously carried out this type of study, but with the incorporation of a new perspective, an additional discipline, it is possible to reach more complete conclusions.
The research carried out by Dr. García arises to try to answer what are the effects that altitude has on some elements of the cardiovascular system, specifically in three arteries: the carotid, the aorta and the femoral, to determine how it affects in their functions.
“The arteries not only carry the blood, but also allow the pressure wave delivered by the heart to be regulated, in such a way as to deliver a more or less regular blood flow and pressure. To do this, they make use of their mechanical and elastic properties, and thus autonomously regulate blood flow”, specified Claudio García regarding his research.
The question is how does hypoxia affect the arterial functions of the heart? Many people who work at heights, such as miners, are affected by “hypoxic cycles,” which are for a few days in a situation above 2,500 meters, and then go down to a few days off. To adapt to the condition of lower oxygen pressure, the physiology of the human body rapidly increases the respiratory and heart rate, which can cause discomfort and decompensation in people with chronic cardiopulmonary diseases.
Some professors from the Universities of Chile, Universidad Católica and O’Higgins also participate in this research as collaborators, who follow other physiological effects that altitude can produce in the arteries. “The study is quite interesting, because it combines several aspects of what happens in blood vessels”, highlights the Usach teacher.
DICYT source : https://www.dicyt.com/noticias/estudian-como-la-hypoxia-genera-changes-biomecanicos-en-el-sistema-cardiovascular