Manned interplanetary missions: prospective medical problems.

The present review aimed to suggest approaches to prospective medical problems related to the health maintenance of space crews during future manned interplanetary, particularly Martian, missions up to 2-3 years with a possible stay on a planet with gravity different from that on Earth. The approaches are based on knowledge so far obtained from our analysis of the medical support of long-term orbital flights up to one year, as well as on the consideration of specific conditions of interplanetary missions. These specific conditions include not only long-term exposure to microgravity, but also a prolonged stay of unpredictable duration (2-3 years) on board a spacecraft or on a planet without direct contact with Earth, and living in a team with a risk of psychological incompatibility and the impossibility of an urgent return to Earth. These conditions necessitate a highly trained medical person in the crew, diagnostic tools and equipment, psychophysiological support, countermeasures, as well as the means for urgent, including surgical, treatment on board a spacecraft or on a planet. In this review, the discussion was focused on the following predictable medical problems during an interplanetary mission; 1) unfavorable effects of prolonged exposure to microgravity, 2) specific problems related to Martian missions, 3) medical monitoring, 4) countermeasures, 5) psychophysiological support and 6) the medical care system.