tially ameliorated by administration of vitamin A (Talas et al., 2002, 2003). Similar studies into fracture healing and the immune system in a prolonged space environment are outlined in the BR. Because of the likelihood that injuries will occur and the paucity of mitigation strategies at present, these and related studies must be given high priority. Similarly, the issue of drug stability in high-radiation environments mentioned earlier (see discussion of radiation) has to be addressed.
In the operational category, studies during parabolic flight have provided some guidance into issues such as airway management, cardiopulmonary resuscitation (CPR), control of body fluids (e.g., blood) in microgravity, and suction. A simple example of the operational challenges is apparent in the application of CPR: both victim and rescuer must be mechanically stabilized in order to deliver effective chest compression in microgravity, and there are few data that evaluate the effectiveness of CPR in providing organ perfusion under these conditions. Neither adequate suction—a basic requirement for airway management—nor the capability to vary inhaled oxygen concentration is currently available on the ISS (Bacal et al., 2004).
Both the biological and the operational research issues are aimed not at fundamental science, but at support of the specific health care delivery issues that are focused on crew health and mission success. What to treat? What not to treat? What to take in the vehicle’s medical supply manifest? Precedents from the body of literature on health care rationing may be applicable to guide some of these health care delivery questions. An extensive review of the literature on health care in nonterrestrial environments, including a compilation of translated relevant Russian scientific literature, indicated that “the majority of resuscitative and surgical interventions required to stabilize a severely injured astronaut are feasible in a microgravity environment” (Kirkpatrick et al., 1997). However, the applicability of other health care techniques in such environments and the limitations imposed by upload volume and mass may preclude the availability of many techniques and impose a limited selection of options based on risk assessment and logistics. Cost–utility analysis should incorporate probabilistic modeling of the likelihood of encountering a specific adverse event and the benefit—both to the mission and to the individual—of taking action during the mission to mitigate the health problem (Sculpher et al., 2004; Seifan and Shemer, 2005).
As an example, what is the probability that a crew member will develop a malignancy during the mission? Breast cancer might serve as an