1. Space Medicine 1 Operational Space Medicine Douglas Hamilton, M.D, Ph.D Wyle Laboratories NASA Johnson Space Center Houston, TX, USA Star Trek TV Series. Photo Paramount Pictures Kluwer Academic Publishers Copyright © 2003 All rights reserved Fundamentals of Space Medicine — Chapter 7

2. Space Medicine 2 Key Concepts Space medicine: What is it? What are the health hazards of spaceflight. Comparison with analog environments Medical selection of astronauts and prevention of health hazards In-flight countermeasures Treatment of medical events in space. The onsite medical facility. Emergency and rescue

3. Space Medicine 3 What it is –It involves proactive and reactive care of humans to optimize physical, physiological, and mental well-being, within the unique constraints of an extreme environment What it isn’t –Space Medicine is different from Space Physiology –Many aspects of adaptation to weightlessness are peculiarities, not necessarily pathology –Even if not pathological, changes may alter the way a disease presents or may increase risks for a given medical problem Photo NASA

4. Space Medicine 4 “Your neuro-vestibular, cardio-vascular, and musculo- skeletal systems can’t support you anymore.”

5. Space Medicine 5 Operational Space Medicine Selection and Prevention are the primary means of maintaining crew health and performance Countermeasures are used when Selection and Prevention are unable to mitigate the deleterious effects of spaceflight Treatment is used when Selection, Prevention, and Countermeasures are unable to prevent or mitigate illness or injury Rehabilitation: return to flight status

6. Space Medicine 6 History of Space Medicine Photos NASA

7. Space Medicine 7 Astronaut Selection Medical history Examination –Physical exam –Cardio-pulmonary –Ear-Nose-Throat –Ophtalmological –Dental –Neurological –Psychiatric –Radiographic –Laboratory Others –U.S.: Drug screen, microbiological, pregnancy, STD –Russia: Decompression and hypoxia Centrifuge for +Gz and +Gx resistance Rotating chair Tilt table studies LBNP Heat stress Parabolic flight

8. Space Medicine 8 Astronaut Training Jet training Emergency egress training Medical training Water training Photos NASA Photo CNES Photo NASA

9. Space Medicine 9 Risk Assessment Most tests have a poor ability for detecting the presence of disease in very healthy individuals There are almost no tests which are designed to select-out the occurrence of pathology (illness) over the next three years. This is a problem for selecting a crew for a Mars Mission All risks cannot be predicted Movie: 09_AlienSong

10. Space Medicine 10 Common Medical Events Space Motion Sickness: count on 50-70% Foreign bodies in the eye: particles do not “settle out” Decompression-related disorders: especially with active EVA schedule Toxic inhalation: e.g. from chemicals/reagents involved in investigations, pyrolysis products from fire, propellants Kidney stones: risk due to mobilization of calcium from skeleton, and possibly other factors Radiation: identified as the major career-limiting exposure for astronauts Photo NASA

11. Space Medicine 11 Less Likely Medical Events Cardiovascular events: rigorous screening process during astronaut selection, flight certification Major fractures: largely, forces which lead to such events terrestrially, such as vehicle accidents and falls, not present Infectious disease: after a certain disease free “incubation period” no new pathogens introduced into a small group (however, there are also immune system changes with unclear effects on overall risk) Note: all the above represents a large portion of events prompting visits to medical care facilities on Earth

12. Space Medicine 12 Source of Ionizing Radiation in Space Solar energetic particles emitted from the sun during solar flares Particles trapped by the Earth’s magnetic field in the Van Allen belts, Galactic cosmic radiation which crosses the galaxy Each of these sources consists of all the types of space radiation, but at different energies and in different relative proportions

13. Space Medicine 13 Acute Radiation Syndrome Dose (Sv)Probable Medical Effects 0.1-0.5No effects except minor blood changes 0.1-15-10% subjects experience nausea or vomiting, fatigue for 1-2 days, slight reduction in white blood cells 1-225-50% nausea/vomiting, with some other symptoms, 50% reduction in white blood cells 2-3.575-100% nausea/vomiting, fever, with anorexia, diarrhea, minor bleeding, 75% reduction in all blood elements. 5-50% subjects will die 3.5-5.5100% nausea/vomiting, fever, bleeding diarrhea, emaciation. Death of 50-90% in 6 weeks. Survivors require 6 months convalescence 5.5-7.5100% nausea/vomiting in 4 hours. 80-100% die 7.5-10Severe nausea/vomiting for 3 days. Death within 2.5 weeks 10-20Nausea/vomiting within 1 hour. 100% die within less than 2 weeks 45Incapacitation within hours. 100% die within 1 week

14. Space Medicine 14 Radiation Exposure Exposure Limits for Ionizing Radiation BFOEye Skin 30 Days0.2511.5 Annual0.523 Career1-4*46 *The career dose-equivalent (in Sievert, Sv) is based upon a maximum 3% lifetime risk of cancer mortality. BFO: blood-forming organs Measured Radiation Dose during Spaceflight MissionAbsorbed Dose(mGy) Dose Equivalent (Sv) Space Shuttle2-40.005 Sv (7-day mission orbiting Earth at <450 km) Space Shuttle5.20.05 Sv (8-day mission orbiting Earth at >450 km) Apollo-1411.40.03 Sv (9-day mission to the Moon) Skylab-477.4 0.178 Sv (84-day mission orbiting Earth at 430 km, 28.5 deg inclination) Mir1460.584 Sv (1-year mission orbiting Earth at 400 km, 51.5 deg inclination)

15. Space Medicine 15 Radiation Shielding TimeEvent 06:21Optical flare observed 13:0030-day limit exceeded for skin and optical lens 14:0030-day limit exceeded for BFO; annual limit exceeded for lens 15:00Annual limit exceeded for skin 16:00Annual exceeded for BFO; Career exceeded for lens 17:00Career limit exceeded for skin Effects of a Solar Flare Event with 2 g/cm 2 shielding (Aug’72) Shield ThicknessBFOSkinLens 0.2 (g/cm 2 )6.03.01.9 1.0 (g/cm 2 ) 6.33.52.4 5.0 (g/cm 2 ) 8.98.06.5 Time to reach 30-day limit (hours) Photo NASA

16. Space Medicine 16 Rules in Space Medicine “Common things occur commonly” Mission-specific operational hazards: e.g., harmful environment, toxic substances, etc. Injury / illness is occurring in a body which is adapting to microgravity Manpower is in short supply In-flight, the crew is on its own with limited support from Earth Photo CNES

17. Space Medicine 17 Medical Hardware Selection Weight/volume: as small and compact as possible Simple and intuitive to use; training will be limited Power/data needs: add immensely to complexity; non-powered if possible Long shelf-life, "bullet proof” technology desired Supports identified standards of care; must meets clinical management analysis, e.g. provides useful information Modular, easy to replace and upgrade components Think 0-G or partial G as needed Photo NASA

18. Space Medicine 18 ISS Crew Health Care System (CHeCS) Health Maintenance System –Body Restraint System –Cardiac defibrillator –Advanced Life Support Pack –Human Research Facility Gas Analyzer System Heart and vascular ultrasound Abdominal ultrasound, deep organ Gynecological ultrasound Muscle and tendon ultrasound Transcranial ultrasound Environmental Health System Countermeasures System –Treadmill –Cycle ergometer –Resistive exercise First ultrasound examination (lungs) performed on board the ISS. Documents NASA Movie: 18_lungs

19. Space Medicine 19 Examples of Flight Medical Hardware Cardiac Defibrillator / Monitor –Early electrical defibrillation correlates best with survival in event of cardiac arrest (many roads to ventricular fibrillation) –It is no longer simple to apply force to defibrillator paddles; adhesive conductive pads are used –Must provide insulation from delivered voltage and consider effects of electromagnetic interference (EMI) on sensitive avionics Photo NASA

20. Space Medicine 20 Examples of Flight Medical Hardware Advanced Life Support Pack –Accessibility and use strongly influence success / survival –Medical waste, e.g., sharp needles must be carefully disposed –Medications must be tracked and discarded when shelf-life exceeded –Absorption of oral medications may be sensitive to digestive function, which may be altered in space –Alternate routes of administration may be better for some drugs (intramuscular, intravenous, nasal) Photos NASA

21. Space Medicine 21 Advanced Life Support Pack Document NASA Deployment and utilization of the Advanced Life Support Pack on board the ISS Movie: 21_contingency

22. Space Medicine 22 Telemedicine Care Medical Officer (CMO) Onboard Medical Care Facility Injured or ill Crewmember Telemedicine Link Crew Surgeon Engineering Support Consultants

23. Space Medicine 23 Telemedicine Pack Voice / video communications both ways (private medical conferences, diagnostic and procedural aid) Continuous physiological monitoring (eases requirements on crew; ground personnel can analyze trends) Video Imaging –Eye –Ear, nose, throat –Skin Biomedical Monitoring –ECG –SpO 2 –Blood pressure –Heart rate Electronic Stethoscope – Heart, lung, and bowel sounds Photo NASA

24. Space Medicine 24 Emergency and Rescue Response to an orbital medical event depends on 5 factors: –Severity of illness / injury –Capability of onboard medical system –Ability of surgeon to assist during medical event –Level of skill / training of onboard medical officer –Ease / feasibility of medical evacuation to Earth Crew Medical Officer –3 -7 crewmembers on ISS –Crew Medical Officer (CMO) on ISS is usually not a physician –CMO receives 40-60 hours of medical training completed at least 3 months prior to flight –Trained to recognize, treat, and stabilized acute injury –Trained to prepare patient for transport

25. Space Medicine 25 Treatment Treatment structure highly desirable Requires means of transporting patient Necessary medical hardware in proximity Restraint function integrated with diagnostic and therapeutic systems Some new procedures need to be adapted for microgravity (e.g., CPR) Documents NASA Movie: 25_restraint

26. Space Medicine 26 Surgery in Space Operator and patient restraints Instrument deployment and fixation Sterile environment –Increased population of antibiotic resistant bacteria –Decreased immune function documented in space Lighting and exposure Control of atmosphere contamination (bleeding) Decreased proprioceptive (muscle and skin) sensation Time delay for telesurgery Photo NASA

27. Space Medicine 27 Emergencies — Soyuz Photos NASA

28. Space Medicine 28 Emergencies — Egress Photos NASA

29. Space Medicine 29 Additional Reading Billica RD, Simmons SC, Mather KL, et al. (1996) Perception of the medical risk of spaceflight. Aviat Space Environ Med 67: 467-473 Clément G (2003) Fundamentals of Space Medicine. Dordrecht: Kluwer Academic Publishers Lane HW, Schoeller D (eds) (1999) Nutrition in Spaceflight and Weightless Models. Boca Raton, FL: CRC Press Wilson WJ, Miller J, Konradi A, Cucinotta FA (eds) (1997) Shielding Strategies for Human Space Exploration. NASA CP- 3360 Washington, DC: NASA Institute of Medicine (2001) Safe Passage: Astronaut Care for Exploration Missions. Ball HR, Evans CH, Ballard JR (eds) Washington, DC: National Academy Press International Workshop on Human Factors in Space. Aviat Space Environ Med 71, Number 9, Section II (Supplement) 2000 National Research Council (1996) Radiation Hazards to Crews of Interplanetary Missions. Task Group on the Biological Effects of Space Radiation. Washington, DC: National Academy Press