The characteristics and significance of intrathoracic and abdominal pressures during Qigong (Q-G) maneuvering.

In order to investigate the mechanism of raising the blood pressure by the
Qigong (Q-G) maneuver, the changes of esophageal and gastric pressures were determined during this maneuver, and the data were compared with those from the L-1 maneuver. Eight subjects performed the Q-G maneuver at +1 Gz; their esophageal pressures (mean +/- S.D.) were -6.7 +/- 2.1 mm Hg in the inspiratory phase and 0.1 +/- 3.7 mm Hg in the expiratory phase; intragastric pressures (mean +/- S.D.) were 69.5 +/- 20.2 mm Hg and 63.4 +/- 22.6 mm Hg, respectively. In 22 centrifuge runs at +4.0 to 7.5 Gz and during Q-G maneuvering, 5 subjects had esophageal pressures of -9.0 +/- 3.3 mm Hg in the inspiratory phase and 1.6 +/- 7.2 mm Hg in the expiratory phase, and gastric pressures of 140.6 +/- 23.2 mm Hg and 138.7 +/- 29.5 mm Hg, respectively. The results showed that during Q-G maneuvering, even with a high-G load, the thoracic pressure remained negative or at low pressures while gastric pressures were remarkably raised. They both fluctuated little during respiration; therefore, a relatively large and constant pressure gradient between abdominal and thoracic pressures was maintained. Here lies the significant characteristic of blood pressure raising by the Q-G maneuver. It might possess theoretical significance for further study and development of anti-G maneuvers.