[Medical provisions for non-career cosmonauts on short-duration flights to the International Space Station]

The paper presents the factual data about 6 participants in short-duration space flights of three age groups (according to the WHO classification). The scope of medical care for three young SFPs whose health status was qualified as good replicated the program adopted in Russia for crewmembers trained for short-duration orbital flights. To safeguard three SFPs of middle and elderly age among whom two had deviations in body functions, the standard medical care program was reinforced by prescription of corrective pharmaceuticals to be taken during space flight, supply of personal kits with preventive medicine, inclusion of additional examinations into the standard medical monitoring and modification of the in-flight countermeasure program, if necessary. As a result, all the SFPs missions were accomplished safely and successfully.

[Experience of an adaptation-assisting agent of animal origin during prolonged isolation and confinement]

The utility of pantohematogen, an adaptation-assisting agent of animal origin for mental performance and functioning of the body systems was assessed in volunteered subjects exposed to prolonged isolation and confinement. Pantohematogen was shown to be favorable for successful implementation of control operations tests without any side effects on the main body systems and, therefore, can be recommended as a way to improve mental performance and to treat asthenoneurotic disorders in extreme conditions.

[Testing and selection of equipment to simulate in-flight telemedicine-assisted medical examinations and researches on the ISS Russian segment]

Analysis of equipment and systems used in telemedicine consultation was fulfilled from the perspective of integration into the ISS RS.

[Several clinical aspects of a piloted Martian flight]

The authors consider factors and risk sources in long and superlong (interplanetary) missions, conceivable effects of extended exposures in microgravity, and probability of diseases in the crew. They also lay down the basic principles of medical care, including surgery, to be applied in the interplanetary mission, and propose a nomenclature of key means and equipment for the therapeutic and emergency medical care, and a configuration of a medical compartment.

[Peculiarities of anesthesia and systemic hemodynamics in experiment with 30 days head-down immobilization of monkeys]

Two series of surgery (biopsy) were performed before and after 30-d head-down immobilization (HDI) of monkeys. The animals were anaesthetized by inhaled isoflurane. Effects of immobilization on systemic hemodynamics and the progress of anesthesia were evaluated. The experiment showed that HDI reduces systemic arterial pressure and slightly increases heart rate (HR) irrespective of the use of anesthesia. However, comparison of systemic hemodynamics parameters before and after the 30-d immobilization also revealed a drop in systemic arterial pressure, both systolic and, to a less degree, diastolic but not a significant rise in HR during the second surgical operation.

[The pharmacodynamic and pharmacokinetic characteristics of furosemide and furesis]

The object of the work was comparative study of the special features of the pharmacodynamic and pharmacokinetic properties of the diuretics furosemide and furesis in an ambulant regimen with the subject lying in an antiorthostatic position. Six practically healthy males were examined. They were given per os either 40 mg furosemide or one tablet of furesis (49 mg furosemide and 50 mg triamterine). Blood from the vein and urine were repeatedly tested.

[Modernization of methods amd technical means of information supply of piloted space flights]

The goal was to lay basis for a change to modern, adequate to international standards technology of the biomedical data transfer to and from the orbital complex, and setting-up a computer network to link all partners in the medical care systems for space missions. Main sources of the board biomedical information were identified as well as associated restrictions on communication capabilities and upgrading the in-flight procedures. Advantages of INTERNET were analyzed and the need for high-speed digital downlink of the biomedical data was substantiated.

Blunt trauma and operative care in microgravity: a review of microgravity physiology and surgical investigations with implications for critical care and operative treatment in space

BACKGROUND

The assembly of the International Space Station in a low earth orbit will soon become a reality. The National Aeronautics and Space Administration envisions inhabited lunar bases and staffed missions to Mars in the future. Increasing numbers of astronauts, construction of high-mass structures, increased extra-vehicular activity, and prolonged if not prohibitive medical evacuation times to earth underscore the need to address requirements for trauma care in nonterrestrial environments.

STUDY DESIGN

A search was carried out to review the relevant literature in the MEDLINE and SPACELINE databases. All related Technical, Corporate, and Flight Test Reports in the KRUG Life Sciences corporate library were also reviewed. Bibliographies of all articles were then reviewed from these papers to identify additional pertinent literature. Senior Russian investigators reviewed the Russian literature and translated Russian publications when appropriate. Personal communication and discussion with active microgravity investigators and ongoing microgravity research supplemented published reports.

RESULTS

A large volume of data exist to document the multiple detrimental physiologic effects of microgravity exposure on human physiology. Organs systems such as cardiovascular, neurohumoral, immune, hematopoetic, and musculoskeletal systems may be particularly affected. These physiologic changes suggest an impaired ability to withstand major systemic trauma. Observational data also suggest adverse changes in numerous aspects of response to wounding and injury, and in areas such as the behavior of hemorrhage, microbiologic flora, and wound healing. In addition to an increased volume of ongoing and anticipated basic science research in microgravity physiology, preliminary studies of clinical diagnosis and therapy have been carried out in microgravity and microgravity laboratories. The feasibility of a wide range of ancillary critical care techniques has been verified in the parabolic flight model of microgravity. Although Russian investigators first performed laparotomies on rabbits in parabolic flight in 1967, only recently have American investigators demonstrated the reproducible feasibility of open and endoscopic surgical procedures under general anesthetic in animal models in a microgravity environment.

CONCLUSIONS

With appropriate instrumentation and personnel, the majority of resuscitative and surgical interventions required to stabilize a severely injured astronaut are feasible in a microgravity environment. Onboard limitations in mass, volume, and power that are ever present in any spacecraft design will limit the realistic capabilities of the medical system. Standard proved and tested trauma and operative management protocols will constitute the basis for extra-terrestrial care. Surgeons should familiarize themselves with the microgravity environment and remain active in planning trauma care for the continued exploration of space.

[A filtration study of erythrocyte deformability]

The study of two flow methods (constant flow method and initial flow rate method) has been conducted to specify and compare methodological approaches to quantitation of red cell deformability. Washed red cells were resuspended in saline medium with glucose and albumin and examined for deformability by the above methods under different conditions. The parameters are presented to characterize flow curves obtained with the constant flow method. The authors have established optimal conditions for the measurements: the composition of the medium, the suspension HCT, leukocyte number, filtrate types, etc. With meeting of the above methodological requirements, both the methods permit quantitation of red cells deformability and can be utilized for stored blood and erythrocyte mass quality control.

[Hematological parameters of cosmonauts during space flight]

This paper present hematological data obtained during space flights of the third and the fourth prime crew flights (EO-3 and EO-4). In the EO-3 flight, RBCs, WBCs and blood formed elements were counted by the cosmonaut-researcher. In the EO-4 flight, blood was drawn by the cosmonaut-researcher and analyzed on the ground; also, blood smears treated in the Microview unit and videotaped were used. Blood parameters in EO-3 and EO-4 crewmembers were close or equal to the normal. However there were cases with changes in bends, myelocytes, neutrophils, lymphocytes; also anisocytosis, hypochromia, target-like erythrocytes, and single acanthocytes were seen. Comparison of blood smears on unstained and stained glass slides revealed significant differences in the amount of target-like erythrocytes in the same cosmonaut at the same time (on the prestained glass slide only 4 erythrocytes and no aggregates in single fields of vision were detected while on the unstained glass slide aggregates in single fields of vision were seen). Pre- and postflight examinations of bone marrow revealed polymorphocellular marrow and mature hemopoietic cells.

[Changes in the rheological indicators of the blood and hemodynamics during 14-day anti-orthostatic hypokinesia]

Nine essentially healthy subjects, aged 25 to 42 years, were exposed to head-down bed rest (-8 degrees). On bed rest days 3, 7 and 14 the following rheological and hemodynamic parameters were measured: blood dynamic viscosity, Caisson viscosity, yield limit, red blood cell aggregation, stroke volume, cardiac output, and total peripheral resistance. Rheological parameters were measured by means of a rotation viscosimeter at 25 degrees C +/- 0.1. Hemodynamic parameters were measured by the method of integrated rheography. Blood was withdrawn from the cubital vein. The results give evidence that dynamic and Caisson viscosity increased significantly, reaching a peak by bed rest day 14. The sequence of hemodynamic changes followed the same pattern as rheological changes. Analysis of the results shows that there is a good correlation between the above parameters, especially by bed rest day 14. Thus, it can be concluded that there is a vascular mechanism involved in the compensatory restructuring of the vascular system at the tissue level in response to blood redistribution and fluid loss during bed rest.

[Anti-bacterial protection of patients during rendering of specialized medical services]

This paper surveys the available equipment and techniques to provide bacterial protection of out-patients given medical aid. It presents a classification of the medical equipment in terms of the design, spectrum of application and type of aid. It is emphasized that patients treated outside a hospital need bacterial protection. Methods for purifying and sterilizing the equipment as well as procedures for maintaining the preset environmental parameters are described. The paper outlines technical problems the solution of which may help the development and use of bacterial protection devices to be applied in special conditions.

[Changes in regional pulmonary hemodynamics and levels of vasoactive substances in man in a state of antiorthostatic hypokinesia]

A comparative evaluation of rheographic changes in regional pulmonary hemodynamics and renin-angiotensin and kinin-kallikrein activities was carried out on 9 volunteers exposed to antiorthostatic hypokinesia (-8 degrees) for 14 days. It was found that pulmonary circulation shifted in the apical direction due to increase in arterial tonicity and phasic variations of venous lumen. During the study blood renin increased significantly (P less than 0.05) whereas prekallikrein and kallikrein inhibitor varied insignificantly. It was concluded that the renin-angiotensin system played and important role in the changes of functional topography of pulmonary circulation in simulated microgravity conditions.

[Effect of hemosorption on rheological indicators of blood during 7-day anti-orthostatic hypokinesia and in in vitro tests]

The effect of hemosorption of blood rheology was examined in 9 healthy men exposed to headdown tilt (-8 degrees). Venous-venous hemosorption was performed on tilt day 7 using activated charcoal SKN-2M. It was found that by tilt day 7 rheological parameters increased significantly and returned to the norm after 2-hour hemoperfusion through activated charcoal. This shows that hemosorption produces a beneficial effect on blood rheology and microcirculation which is indicated by a direct examination of eye microvessels. Experimental in vitro studies using oxygenated and nonoxygenated donor's blood demonstrated that hemosorption combined with blood oxygenation can noticeably increase the effectiveness of perfusion on the whole.

[Paramecium test for toxic substances in the blood of humans exposed to conditions simulating weightlessness]

The Paramecium test was for the first time used to measure the build-up of toxic substances in the healthy man exposed to simulated weightlessness. The most distinct changes were seen on bed rest days 3 and 7-8 in all test subjects (41 subjects). After bed rest day 8 the parameter reached a plateau, the toxicity level stopped to increase, but the Paramecium test time remained shorter than normal. It can therefore be suggested that the prognosis of any disease that may develop in this situation will be worse. In view of this it is important to improve the prophylaxis and treatment of endogenous and exogenous intoxications during space flight and to provide active detoxication based on the purification of biological fluids by sorption.

[Rheological blood indicators during motor activity of various degrees]

Blood rheological parameters of essentially healthy people were examined during exercises of a maximal workload and 14-day head-down tilt. The results obtained indicate that in the people performing normal and increased motor activity some rheological parameters were different. Changes in the rheological parameters of blood after head-down tilt and exercises with a maximal workload suggest the existence of a blood viscosity threshold above which physical work capacity declines significantly. The capacity can be restored through a correction of blood viscosity in the recovery period. The basic rheological properties of blood can be improved by regular physical training.

[Experience in the use of standard perfusion packings for hemosorption]

A fixture for locking the perfusion packing to all types of the standard bottles with non-threaded neck is proposed. It consists of a metal ring, a yoke and two stop screws. The fixture has been clinically tested in the course of 45 hemosorption procedures.

[Changes in regional hemodynamics and gas exchange in healthy males after moderate blood loss and blood reinfusion in response to antiorthostatic hypokinesia]

Nine healthy male test subjects were exposed for 7 days to head-down tilting. Within 2 hours after exposure 500 ml of blood were withdrawn. This reduced pulse blood filling of all lung compartments, particularly upper (P less than 0.05) compartments, and decreased slightly finger circulation. The blood losses were then substituted but 2 hours after blood reinfusion the rheographic parameters of pulmonary circulation were still lower than before blood losses. In arterial blood pCO2 remained lower (P less than 0.05) and the deficiency of bases increased (P less than 0.05). It can be concluded that in the above situation blood reinfusion in the amount exceeding blood losses should be viewed adequate. On the basis of the results obtained increased blood content of the lungs in the course of head-down tilt can be interpreted as a reflex mechanism of blood pooling in the body.

[Effect of 120-day antiorthostatic hypokinesia on gas exchange and pulmonary circulation in humans]

Parameters of gas exchange and pulmonary circulation were measured in five healthy test subjects during 120-day head-down tilt test and early recovery. During the first half of the bed rest study CO2 tension in arterial blood increased significantly. During the second half of the study oxygen and carbon dioxide tension decreased significantly. The mechanisms of these changes are discussed.

[Changes in several indicators of blood rheology in experiments simulating weightlessness]

Changes in blood rheological parameters of 21 male volunteers, aged 25-37 years, were studied. The test subjects were subdivided into three groups. Nine subjects of Group 1 were exposed to head-down tilting (-8 degrees) for 14 days, six subjects of Group 2 were exposed to 7-day continuous immersion, and six subjects of Group 3 to intermittent immersion. During head-down tilting the apparent viscosity and hematocrit and then caisson viscosity increased. By day 7 the coefficient of red blood cell aggregation decreased significantly. These changes persisted till the end of the tilt study. The above rheological parameters returned to normal three days after the exposure. During continuous immersion the apparent viscosity showed the largest changes. Other specific changes included a moderate decrease of hematocrit, lack of significant changes in the yield limit of blood and a tendency towards an increase in the erythrocyte aggregation coefficient. Three days after the exposure the blood viscosity was much higher than before the study. During intermittent immersion rheological changes were induced by the first 36-hour exposure when shifts in blood viscosity and other parameters were most significant. It should be noted that following this exposure 72 hours of normal motor activity did not result in the normalization of the above rheological parameters.

[Problems of anesthesia, surgical care and resuscitation during manned space flights]

When exploring the problems of medical aid to be rendered in manned space flights, it is necessary to take into consideration the specific features of the environment as well as the changes in the human body induced by space flight effects. In space flight anesthesia can be applied using such advanced methods as multi-component balanced anesthesia and peridural anesthesia. Surgery and resuscitation can be performed, employing the procedures and methods that allow operations in an abacterial environment, correction of vital dysfunctions with the aid of artificial pulmonary ventilation, cardiac electrotherapy, and sorptive purification of body fluids. Various aspects of infusion treatment and first medical aid are discussed.

Anesthesia, surgical aid and resuscitation in manned space missions

When discussing problems related to medical service in space flight, particular attention should be given to the specific living conditions and changes associated with space flight. In disease and injury, surgery can be provided only after conservative therapy has failed. In this context gnotobiological chambers allowing surgery in aseptic conditions seem promising. A portable set of interchangeable surgical tools should be made of light-weight alloys that can be readily sterilized. Electroanalgesia in combination with auriculoacupuncture as well as peridureal anesthesia may be used as they allow normal operations in autonomous space flight conditions. Changes in the sympatho-adrenal and kallikrein-kinin systems, as well as water-electrolyte balance, should be taken into account in developing methods and means of medical service in critical situations. Special attention should be given to the prevention and treatment of brain edema in view of weightlessness-induced cephalad fluid shifts.

[Medical provisions for the immediate post-flight period following long space flights]

At the final stage of long-term space flights first aid should be rendered in a specific way in cases of critical situations. Resuscitation and anesthesiology measures should be applied, if necessary, after study of flight-induced changes in the vital organs and systems. The paper describes the most important factors that should determine the tactics of resuscitation-anesthesiology support of the immediate postflight stage, if theoretically feasible acute life-endangering states develop. It also presents substantiated correction of routine clinical protocols of resuscitation aid.