[http://www.stand.physio-angers.fr/scrollsignals]
[./materialspag.html]
[./physiologypag.html]
[./diseasespag.html]
[./animalspag.html]
[./bibliographypag.html]
[./contactpag.html]
[./indexpag.html]
[./statementpag.html]
[./diseasespag.html]
[./diseasespag.html]
Head-Up Tilt test A good way to avoid artifact resulting from postural adjusments or to collect a lot of several signals at the same time (here we collected ECG, blood pressure, thoracic impedance, transcranial doppler, and leg plethysmography). Head-up tilt test is also prefered to standing for the diagnosis of unexplained loss of consciousness in patients because of the risk of transient pass out during the exam and because it is easier for some patients.
[#ANCHOR_Txt1]
[#ANCHOR_Txt3]
[./models2pag.html]
[#ANCHOR_Img6]
[./physiology2pag.html]
Models Some models are usefull to study cardiovascular regulation while standing. The standing position comes with postural adjusments that could artifact some devices, then scientists prefere head-up tilt test. Some models mimic the fluids shift resulting from standing but on a supine subject, like LBNP (Low Body Negative Pressure). You can also observe a standing human whithout fluid shift while standing in water immersion. Another elegant way to understand the cardiovascular regulation is to study situations during which standing is suppressed like during actual or simulated space flight (even on animals!), simulated by bed rest or by supine water dry immersion.
[http://fr.youtube.com/watch?v=dIN1XTDqHoc]
Space flight There are no more fluid shifts in an environment without the earth gravity. So, there is no more standing position. A chance for the cardiovascular physiologist to study how cosmonautes adapt (or rather deadapt) to this new environment. Cosmonautes often collapse back to earth because of this deadaptation during spaceflight (movie) Here, a cosmonaute is collecting his heart rate and his blood pressure aboard Mir station.
[#ANCHOR_Img1]
[./indexpag.html]
[./models2pag.html]
Other models
[./physiology2pag.html]
Lower Body Negative Pressure The suposed main key point of the cardiovascular changes while standing is the fluid shift. LBNP (Lower Body negative pressure) is a way to get a fluid shift on a supine subject: you put him (her) lower part of the body in airtight box (thank to a kayak skirt) connected to a vacuum cleaner. When the vacuum cleaner is running, it sucks the blood toward the lower body!
[Web Creator] [LMSOFT]