Author/Editor     Štrucl, M; Peterec, D; Finderle, Ž; Maver, J
Title     Pressure sensitivity of flow oscillations in postocclusive reactive skin hyperemia
Type     članek
Source     Am J Physiol
Vol. and No.     Letnik 266, št. 5 Pt 2
Publication year     1994
Volume     str. 1762-8
Language     eng
Abstract     Skin blood flow was monitored using a laser-Doppler (LD) flowmeter in 21 healthy volunteers after an occlusion of the digital arteries. The peripheral vascular bed was exposed to occlusion ischemia of varying duration (1, 4, or 8 min) and to a change in digital arterial pressure produced by different positions of the arm above heart level to characterize the pattern of LD flow oscillations in postocclusive reactive hyperemia (PRH) and to elucidate the relevance of metabolic and myogenic mechanisms in governing its fundamental frequency. The descending part of the hyperemic flow was characterized by the appearance of conspicuous periodic oscillations with a mean fundamental frequency of 7.2 +/- 1.5 cycles/min (SD, n = 9), as assessed by a Fourier transform frequency analysis of 50-s sections of flow. The mean respiratory frequency during the periods of flow frequency analysis was 17.0 +/- 2.2 (SD, n = 9), and the PRH oscillations remained during apnea in all tested subjects. The area under the maximum flow curve increased significantly with prolongation of the occlusion (paired t test, P less th. 0.001; n = 9), but showed no dependence on the estimated blood pressure in the digital arteries, which suggests the predominant role of a metabolic component in this part of the PRH response. In contrast, the fundamental frequency of PRH oscillations exhibited a significant decrease with a reduction in the estimated digital arterial pressure (linear regression, b = 0.08, P less th. 0.001; n = 12), but did not change with the prolongation of arterial occlusion despite a significant increase in mean LD flow (paired t test, P less th. 0.001; n = 9).(ABSTRACT TRUNCATED AT 250 WORDS)
Descriptors     BLOOD PRESSURE
ISCHEMIA
SKIN
ADOLESCENCE
ADULT
ARTERIES
FINGERS
FOURIER ANALYSIS
MUSCLE, SMOOTH, VASCULAR
POSTURE
PRESSURE
REGIONAL BLOOD FLOW
TIME FACTORS