Human Pathophysiological Adaptations to the Space Environment - Critical Review of the Article

The article Human Pathophysiological Adaptations to the Space Environment provides insight about how the human body adapts to the conditions in the space. The environment there is made up of high radiations and microgravity which poses a health problem for explorers. Therefore, a space flight predisposes the interested individuals to a wide range of health issues such as cardiovascular illnesses and loss of bone density, which happens over a span weeks to months. The information provided in the article is agreeable given that the authors draw their assertions from real research studies and facts provided by experts. The main stress factors that are associated with space exploration include inability of the body to withstand the high pressure and limited oxygen in the area.

The article indicates that the body is adaptable to different environment through physiological changes in the body processes. However, a certain limit may be reached in extreme conditions such as those in a space flight making the body produce some premonitory signs of a disease. Some of the physiological conditions that the body needs to contend with in such a situation include hypoxia, response to great attitudes, acceleration, and thermal support. While moving, the body experiences forced changes in motion and the person basically depends on breathing support for life. The information provided is quite detailed given that the authors have provided the actual figures for parameters such as the gravitational field.

As indicated in the article, space flight may cause bone density loss, endocrine and sleep disturbances, hematic, and cardiovascular changes. Research studies have shown that these effects usually return to normal once the space explorers are back on earth. However, it could be argued that the studies may not be accurate given that only a small number of subjects exist for analysis. Critical review of these effects on space indicates that the authors are correct to some extent. For instance, it is true that the cardiovascular system may be exhausted by extreme changes in different environmental parameters. While the heart has mechanisms such as sterling forces and the autonomic nervous system to respond to changes in the external environment, too much change in the gravity may alter the fluid distribution in the body. Consequently, as soon as an explorer is exposed to the space environment, they start suffering from space motion sickness while exhibiting symptoms such as nausea, vomiting, malaise, and headache.

Dramatic shift of body fluid and blood pressure due to changes in the environment leads to an increase in the intracranial pressure and the cerebrospinal fluid leading to the symptoms associated with space motion sickness. Due to lack of enough adaptation of the cardiovascular system to the microgravity in this environment, the victims suffer from acute orthostatic intolerance once they are on earth. It has been theorized that the physiological system of the body first adapts to the space environment and is unable to revert back immediately when the astronaut finish their mission. Some scholars have attempted to counter these arguments by providing experimental data to establish the role of different body system in adapting to the changes.

The authors have identified some reflex mechanism in space that lead to engorgement of the central circulation. The article is made interesting and informative by comparing different sets of data that have been released regarding the topic. For instance, it is indicated that the microgravity in space decreases the mean arterial pressure while other studies have indicated that it increases. However, one fact that remains is that the baroreflex mechanisms of the body are able to detect such changes as soon as one is in space leading to appropriate adjustment of the physiological systems.

Endocrine mechanisms have also been associated with the changes in the systems of the body when a person is in space. It is postulated that perfusion of the kidneys is reduced in space due to the upward distribution of body fluids and the concurrent decrease in the pressure gradient. However, the article indicates that kidney functions such as diuresis and plasma filtrations remain normal. Still, conflicting results have shown that the drastic change in the weight of the astronauts due to the changes in gravity leads to increased natriuresis and diuresis. The right position appears to be from the recent studies, as indicated, in the article, which showed that microgravity may not have a huge effect on the kidney but the drastic changes in the fluid distribution deconditioning of the body systems leading to orthostaic hypotension.

Other human body systems that appear to face a physiological change in the event of a space flight include the endothelium, respiratory, and musculoskeletal. The article has explained how each of them adapts to the external environment that is composed of drastic changes. The microgravity in space causes significant differences between the macrovascular and microvascular endothelial cells. Blood redistribution towards the upper part also has an effect on the vasculature of the eyes, which reduces the arterial blood supply and flow pf the venous blood from the eyes. The radiation effects also affect a wide range of systems leading to maladaptation and improper functioning when the astronauts return on earth. This article is very critical in explaining how the body changes in response to space environment which is significantly different from that of the earth.