[Study of the veno-arteriolar reflex in young and elderly subjects by recording of TcPO2].
The variations' measurement of transcutaneous oxygen tension (TcPO2) looks as an interesting local vasomotor reflex (L.V.R.) exploration, particularly on lower limbs arterial occlusive disease. However the possible impacts of physiological ageing upon this reflex have not clearly been evaluated. But they can be better analysed with a dynamic measure of TcPO2 on the first intermetatarsal space of the patient, successively recumbent, sitting standing and walking on a moving walkway. TcPO2 is measured with a Radiometer TCM3 oxygen monitor. Two groups of patients, without any arterial occlusive lesion, have been tested like that: 20 young (mean age: 23.3 +/- 1.8 years) and 16 older subjects (mean age: 68.3 +/- 6 years). In recumbent position, TcPO2 is about 74.05 +/- 5.6 mmHg in young and 62.2 +/- 4.7 mmHg in older subjects (P less than 0.01). From recumbent to sitting position, after 15 seconds TcPO2 is elevating to a maximal value at 1 min 30 sec. (85 +/- 6 mmHg in young--71.5 +/- 5 mmHg in older subjects--P less than 0.01). Whilst in young TcPO2 decreases slowly to a stable value, at 5 minutes, higher than in recumbent (+ 6.3 +/- 0.5 mmHg), in the older TcPO2 increases ever to a stable value higher than in recumbent (+ 12 +/- 0.7 mmHg). For the last ones there is no TcPO2 adaptation from recumbent to sitting position because of the vascular ageing, while the LVR increased from recumbent to standing position. During the walk, the LVR disappears for both of them. These measurements confirm the decrease of vascular reactivity with ageing and oblige to compare the results on same age people, during the arterial occlusive disease exploration, by evaluating the graph kinetics.
Bilesimo
M
M
Service de Rééducation Fonctionnelle, CHRU de Dijon.
Didier
J P
JP
Casillas
J M
JM
Javelas
S
S
Lucet
A
A
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001158:Arteries / Q000502:physiology*; D001785:Blood Gas Monitoring, Transcutaneous; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture; D012018:Reflex; D014680:Veins / Q000502:physiology*
Exploration du réflexe veino-artériolaire chez le sujet jeune et âgé par l'enregistrement de la TcPO2.