Effect of the thigh-cuffs on the carotid artery diameter jugular vein section and facial skin edema: HDT study.
OBJECTIVE
To evaluate the distal arterial, venous and skin changes in a group using thigh cuffs during daytime and in a control group.


METHODS
Cardiac, arterial, venous parameters were measured by echography and Doppler. Skin thickness was measured by high frequency echography.


CONCLUSIONS
Head down position induced plasma volume reduction, increased cerebral resistance, reduced lower limb resistance. The jugular vein increased whereas the femoral and popliteal veins decreased. All these changes were already observed in previous HDT. Common carotid diameter decreased, Front head skin thickness increased and Tibial skin thickness decreased. Eight hours with thigh cuffs increased the cardiac and carotid sizes which is in agreement with the plasma volume increase. Conversely they reduced the cerebral vascular resistance, jugular section and front head edema which may explain the sensation of comfort reported by the subjects. At the lower limb level the thigh cuffs restored the skin thickness to pre-HDT level but enlarged markedly the femoral and popliteal veins. HR, BP, CO, TPR did not change.
Roumy
J
J
Med Physiol Spatiale, CHU Trousseau, 37044 Tours, France.
Diridillou
S
S
Herault
S
S
Fomina
G
G
Alferova
I
I
Arbeille
P
P
D001510:Bed Rest; D002339:Carotid Arteries / Q000033:anatomy & histology*; D003250:Constriction; D004487:Edema / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D005145:Face; D005263:Femoral Artery / Q000502:physiology; D005268:Femoral Vein / Q000502:physiology; D018495:Fluid Shifts / Q000502:physiology*; D018475:Head-Down Tilt / Q000009:adverse effects / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology*; D012867:Skin / Q000503:physiopathology; D013318:Stroke Volume / Q000502:physiology; D013848:Thigh; D014655:Vascular Resistance / Q000502:physiology; D018544:Weightlessness Countermeasures; D018474:Weightlessness Simulation