Model of medical supply demand and astronaut health for long-duration human space flight

Abstract

The medical care of space crews is the primary limiting factor in the achievement of long-duration space missions. (Nicogossian 2003) The goal of this thesis was to develop a model of long-duration human space flight astronaut health and a medical supply demand model in support of such missions. This model will be integrated into an existing comprehensive interplanetary supply chain management and logistics architecture simulation and optimization tool, SpaceNet. The model provides two outputs, Alphah and Mass, for each set of input variables. Alphah is an estimate of crew health and is displayed as a percentage. Mass is a measure of medical consumables expended during the mission and is displayed in kilograms. We have demonstrated that Alphah is a function of three scaling parameters, the type of mission, duration of mission, and gender of crew. The type of mission and gender are linked to radiation fatality data published by NASA and mission duration correlates to predicted incidence of illness and injury and linked to the model through published US Navy submarine crew medical data. The mass of medical consumables (MMC) expended increases with the number of crew, the duration of the mission and the distance of the mission away from the earth. The degree of medical expertise on-board is not necessarily related to a change in consumption of medical supplies but perhaps to a better outcome for the individual infirmed crew member.

(cont.) We have determined that there is no information to incorporate gender into this aspect of the model and that the ages of the crewmembers would also have a negligible effect. Risk was investigated as an additional independent driver in the calculations. This parameter defined as likelihood of a medical event multiplied by impact to the mission, is in line with current NASA planning processes. Although the equations don't currently incorporate this parameter, implementation in subsequent versions of the model would allow for a more granular description of medical supply mass (i.e. laboratory and diagnostic, imaging, medications, surgical supplies, telemedicine and expert systems equipment) needed to support long-duration human operations in space. The framework of SpaceNet does not currently allow for this level of detail but future version of the software would likely develop and integrate this capability.