Chest wall mechanics in sustained microgravity

Wantier, M.; Estenne, Marc; Verbanck, Sylvia; Prisk, G. Kim; Paiva, Manuel

doi:10.1152/jappl.1998.84.6.2060

Cited by 31 publications

(10 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There was an increase in abdominal contribution to tidal breathing, which rose from 31% to 58% in microgravity [21]. This is consistent with results from parabolic flight, in which there was an increase in abdominal wall compliance but not in rib cage compliance [22] consistent with only small changes in chest-wall shape, making for a slightly more circular rib cage [23,24].…”

Section: Lung Volumes and Expiratory Flowssupporting

confidence: 85%

Microgravity and the respiratory system

Prisk

2014

European Respiratory Journal

View full text Add to dashboard Cite

The structure of the lung, with its delicate network of airspaces and capillaries, means that gravity has a profound influence on its function. Studies of lung function in the absence of gravity provide valuable insight into how, for we Earth-bound individuals, its unavoidable effects shape our lung function. Gravity causes uneven ventilation in the lung through the deformation of lung tissue (the so-called Slinky effect), and uneven perfusion through a combination of the Slinky effect and the zone model of pulmonary perfusion. Both ventilation and perfusion exhibit persisting heterogeneity in microgravity, indicating important other mechanisms. However, gravity serves to maintain a degree of matching of these two processes, so that the ventilation/perfusion ratio, and thus gas exchange, remains efficient. Therefore, while both ventilation and perfusion are more uniform in spaceflight, gas exchange is seemingly no more efficient than on Earth. Despite the changes in lung function when gravity is removed, the lung continues to function well in weightlessness. Unlike many other organ systems, the lung does not appear to undergo structural adaptive changes when gravity is removed, and so there is no apparent degradation in lung function upon return to earth, even after 6 months in space. @ERSpublicationsThe structure of the lung means that gravity has a profound influence on its function

show abstract

Section: Lung Volumes and Expiratory Flowssupporting

confidence: 85%

Microgravity and the respiratory system

Prisk

2014

European Respiratory Journal

View full text Add to dashboard Cite

show abstract

“…Interestingly, spaceflight also resulted in a significant reduction in rib B.Ar in unoperated control animals (Flight + Sham vs. Ground + Sham), which may be explained by the reduction in rib cage expansion observed during breathing in astronauts 31 .…”

Section: Discussionmentioning

confidence: 96%

The effects of spaceflight and fracture healing on distant skeletal sites

Dadwal

Maupin

Zamarioli

et al. 2019

Sci Rep

View full text Add to dashboard Cite

Spaceflight results in reduced mechanical loading of the skeleton, which leads to dramatic bone loss. Low bone mass is associated with increased fracture risk, and this combination may compromise future, long-term, spaceflight missions. Here, we examined the systemic effects of spaceflight and fracture surgery/healing on several non-injured bones within the axial and appendicular skeleton. Forty C57BL/6, male mice were randomized into the following groups: (1) Sham surgery mice housed on the earth (Ground + Sham); (2) Femoral segmental bone defect surgery mice housed on the earth (Ground + Surgery); (3) Sham surgery mice housed in spaceflight (Flight + Sham); and (4) Femoral segmental bone defect surgery mice housed in spaceflight (Flight + Surgery). Mice were 9 weeks old at the time of launch and were euthanized approximately 4 weeks after launch. Micro-computed tomography (μCT) was used to evaluate standard bone parameters in the tibia, humerus, sternebra, vertebrae, ribs, calvarium, mandible, and incisor. One intriguing finding was that both spaceflight and surgery resulted in virtually identical losses in tibial trabecular bone volume fraction, BV/TV (24-28% reduction). Another important finding was that surgery markedly changed tibial cortical bone geometry. Understanding how spaceflight, surgery, and their combination impact non-injured bones will improve treatment strategies for astronauts and terrestrial humans alike.

show abstract

“…The subjects were equipped with two respiratory inductive plethysmograph (RIP) belts, placed respectively on the rib cage (RC) and the abdomen (AB) for the recording of the thoracic and abdominal respiratory movements. After calibration by an isovolume maneuver, the sum of these signals, each proportional to cross-section variation, is used as a measure of the lung volume variation (40). An electrocardiogram (ECG) was recorded with a traditional three-lead configuration.…”

Section: Methodsmentioning

confidence: 99%

“…Before the paced breathing protocols, three standard isovolume maneuvers were performed at FRC with a closed glottis, which allowed the calibration of RIP on the AB and RC signals to give a signal proportional to the respired volume. During the isovolume maneuver, the ratio of volume motion coefficients (X/Y) is equal to the ratio of RC/AB signal amplitude (40). The respired volume was computed using the following equation: ⌬Vol ϭ X AB ϩ Y RC where X and Y are the RIP volume motion coefficients.…”

Section: Methodsmentioning

confidence: 99%

Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans

Migeotte

Prisk

Paiva

2003

American Journal of Physiology-Heart and Circulatory Physiology

Self Cite

View full text Add to dashboard Cite

We studied heart rate (HR), heart rate variability (HRV), and respiratory sinus arrhythmia (RSA) in four male subjects before, during, and after 16 days of spaceflight. The electrocardiogram and respiration were recorded during two periods of 4 min controlled breathing at 7.5 and 15 breaths/min in standing and supine postures on the ground and in microgravity. Low (LF)- and high (HF)-frequency components of the short-term HRV (< or =3 min) were computed through Fourier spectral analysis of the R-R intervals. Early in microgravity, HR was decreased compared with both standing and supine positions and had returned to the supine value by the end of the flight. In microgravity, overall variability, the LF-to-HF ratio, and RSA amplitude and phase were similar to preflight supine values. Immediately postflight, HR increased by approximately 15% and remained elevated 15 days after landing. LF/HF was increased, suggesting an increased sympathetic control of HR standing. The overall variability and RSA amplitude in supine decreased postflight, suggesting that vagal tone decreased, which coupled with the decrease in RSA phase shift suggests that this was the result of an adaptation of autonomic control of HR to microgravity. In addition, these alterations persisted for at least 15 days after return to normal gravity (1G).

show abstract

Chest wall mechanics in sustained microgravity

Cited by 31 publications

References 15 publications

Microgravity and the respiratory system

Microgravity and the respiratory system

The effects of spaceflight and fracture healing on distant skeletal sites

Microgravity alters respiratory sinus arrhythmia and short-term heart rate variability in humans

Contact Info

Product

Resources

About