Elevated End-Tidal Pco2 During Long-Duration Spaceflight
| Autor: | Richard L. Hughson, Danielle K. Greaves, Nicholas J. Yee |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
medicine.medical_specialty business.industry General Medicine respiratory system Respiratory compensation Spaceflight End tidal pco2 pCO2 respiratory tract diseases law.invention 03 medical and health sciences 030104 developmental biology law Internal medicine medicine Cardiology Arterial pCO2 business Short duration circulatory and respiratory physiology Balance (ability) Intracranial pressure |
| Zdroj: | Aerospace Medicine and Human Performance. 87:894-897 |
| ISSN: | 2375-6314 |
| DOI: | 10.3357/amhp.4598.2016 |
| Popis: | BACKGROUND Elevated ambient Pco2 in the International Space Station (ISS) has been cited as a potential contributor to the vision impairment intracranial pressure syndrome (VIIP), a significant health risk for astronauts during long-duration space missions. The elevation in ambient Pco2 is rather modest and normal respiratory compensation could minimize the impact on arterial Pco2. METHODS In nine male astronauts, breaths measured prior to a rebreathing maneuver were examined to assess inspired and end-tidal Pco2 during upright seated preflight and in-flight conditions. RESULTS Inspired Pco2 increased from preflight baseline (0.6 ± 0.1 mmHg) to in flight (3.8 ± 0.4 mmHg). End-tidal Pco2 also increased from preflight baseline (36.0 ± 3.2 mmHg) to in flight (42.1 ± 3.7 mmHg). The difference between end-tidal Pco2 comparing in flight to preflight (6.1 ± 1.6 mmHg) was greater than the difference between inspired Pco2 comparing preflight to in flight (3.3 ± 0.5 mmHg). DISCUSSION The greater increase in end-tidal vs. inspired Pco2 might reflect alveolar hypoventilation due to differences in ventilatory control with spaceflight. These data suggest that further studies should focus on arterial Pco2 and acid-base balance to determine if CO2 dilates cerebral and retinal vessels and might contribute to the incidence of VIIP in astronauts. Hughson RL, Yee NJ, Greaves DK. Elevated end-tidal Pco2 during long-duration spaceflight. Aerosp Med Hum Perform. 2016; 87(10):894-897. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|