scholarly journals Sex features of cutaneous microvasculature in healthy working-age people

2022 ◽  
Vol 20 (8) ◽  
pp. 3111
Author(s):  
K. V. Omelyanenko ◽  
A. Yu. Gorshkov ◽  
A. A. Fedorovich ◽  
A. I. Korolev ◽  
V. A. Dadaeva ◽  
...  

Aim. To study sex characteristics of cutaneous microvascular structure and function in a cohort of healthy working-age people without cardiovascular diseases.Material and methods. The study included 35 healthy men (42±4 years) and 34 women (41 ±5 years). The cardiovascular system was assessed in all patients. The microcirculatory bed of the skin was investigated by the following non-invasive methods: 1) computerized video capillaroscopy; 2) laser Doppler flowmetry; 3) photoplethysmography.Results. According to computerized video capillaroscopy in men, compared with women, there was a smaller number of both functioning capillaries (78 vs 86 capillaries/mm2, respectively (p<0,05)) and their total number (100 vs 120 capillaries/mm2, respectively (p<0,001)). Against the background of a decrease in capillary density in men, there was a higher skin interstitial hydration — 113 vs 96 gm (p<0,005) in men than in women. At the level of precapillary arterioles, where humoral tone regulation prevails. Laser Doppler flowmetry revealed lower pulse amplitude in men than in women — 0,87 vs 1,02 pf, respectively (p<0,05), which indicates a lower arterial blood inflow to exchange microvessels. Against this background, the constrictor response of precapillary arterioles to a sympathetic nervous system stimulation in men is higher than in women — 45% vs 40%, respectively (p<0,05). At the level of large arterioles, where neural tone regulation prevails, photoplethysmography revealed lower augmentation index standardized at a heart rate in men (-4,6 vs 1,7%, respectively, p<0,05), which indicates lower rigidity of muscular vessels in men.Conclusion. In working-age healthy people, sex differences are noted at all cutaneous microvascular levels, which must be taken into account when planning studies.

1995 ◽  
Vol 268 (1) ◽  
pp. H213-H217 ◽  
Author(s):  
H. K. Richards ◽  
M. Czosnyka ◽  
P. J. Kirkpatrick ◽  
J. D. Pickard

Laser-Doppler flowmetry has potential for continuous cerebral blood flow (CBF) measurement in man and experimental animals. However, laser-Doppler flux (LDFx) measured when perfusion is absent (the biological zero, 0biol) does not necessarily coincide with the instrument's electrical zero. To evaluate laser-Doppler flowmetry further we have compared LDFx in rabbits with continuous measurement of the maximum flow velocity (FVx) in the basilar artery using Doppler ultrasonography. Arterial blood pressure (ABP), FVx, and LDFx were measured continuously in anesthetized New Zealand White rabbits. ABP was altered by controlled hemorrhage with subsequent reinfusion. 0biol was estimated from regression analysis of FVx vs. LDFx and compared with 0biol obtained after death. There was a strong linear relationship between LDFx and FVx (r = 0.94). The absolute difference between estimated 0biol and true 0biol was 5.24% of control prehemorrhage LDFx. Variations in 0biol (range 4-409) suggest that percent changes in LDFx must be related to 0biol if results between individual animals are to be compared.


1997 ◽  
Vol 86 (3) ◽  
pp. 438-445 ◽  
Author(s):  
Joseph M. K. Lam ◽  
John N. K. Hsiang ◽  
Wai S. Poon

✓ The authors studied 31 comatose head-injured patients to assess the clinical usefulness of laser Doppler flowmetry (LDF) in continuous autoregulation monitoring. The LDF probes were placed on the surface of the cerebral cortex. Data on LDF, intracranial pressure (ICP), and arterial blood pressure (ABP) were recorded and continuously entered into a computer. The data were broken down into multiple segments of 15 minutes' duration (epochs). Epochs showing rapid change in cerebral perfusion pressure (CPP), change in CPP of less than 10 mm Hg, LDF values of less than five arbitrary units, and loss of ABP/ICP waveform were excluded from further analysis. A linear relationship between LDF and CPP in individual epochs was used as an indicator of loss of autoregulation. The relationship between LDF and CPP changed with time, indicating improvement or deterioration in autoregulation. Longitudinal analysis of all the epochs measured in a patient revealed three patterns of progress: 1) intact autoregulation; 2) transient loss; and 3) persistent loss of autoregulation. All five patients with intact autoregulation had a good outcome. Ten patients experienced transient loss of autoregulation; of these four had a good outcome, five were moderately disabled, and one was severely disabled. Transient impairment of autoregulation did not always indicate poor outcome, provided the impaired autoregulation responded to treatment. In 11 patients who had persistent loss of autoregulation, nine died and two were severely disabled. In five cases the LDF probe lost contact with the cerebral cortex and no useful information was obtained. Real-time measurement of autoregulation using LDF and CPP monitors was achieved and the findings were related to outcome in these patients.


2016 ◽  
Vol 37 (2) ◽  
pp. 694-705 ◽  
Author(s):  
Joseph Donnelly ◽  
Marek Czosnyka ◽  
Spencer Harland ◽  
Georgios V Varsos ◽  
Danilo Cardim ◽  
...  

Intracranial hypertension is a common final pathway in many acute neurological conditions. However, the cerebral haemodynamic response to acute intracranial hypertension is poorly understood. We assessed cerebral haemodynamics (arterial blood pressure, intracranial pressure, laser Doppler flowmetry, basilar artery Doppler flow velocity, and vascular wall tension) in 27 basilar artery-dependent rabbits during experimental (artificial CSF infusion) intracranial hypertension. From baseline (∼9 mmHg; SE 1.5) to moderate intracranial pressure (∼41 mmHg; SE 2.2), mean flow velocity remained unchanged (47 to 45 cm/s; p = 0.38), arterial blood pressure increased (88.8 to 94.2 mmHg; p < 0.01), whereas laser Doppler flowmetry and wall tension decreased (laser Doppler flowmetry 100 to 39.1% p < 0.001; wall tension 19.3 to 9.8 mmHg, p < 0.001). From moderate to high intracranial pressure (∼75 mmHg; SE 3.7), both mean flow velocity and laser Doppler flowmetry decreased (45 to 31.3 cm/s p < 0.001, laser Doppler flowmetry 39.1 to 13.3%, p < 0.001), arterial blood pressure increased still further (94.2 to 114.5 mmHg; p < 0.001), while wall tension was unchanged (9.7 to 9.6 mmHg; p = 0.35).This animal model of acute intracranial hypertension demonstrated two intracranial pressure-dependent cerebroprotective mechanisms: with moderate increases in intracranial pressure, wall tension decreased, and arterial blood pressure increased, while with severe increases in intracranial pressure, an arterial blood pressure increase predominated. Clinical monitoring of such phenomena could help individualise the management of neurocritical patients.


2019 ◽  
Vol 27 (4) ◽  
pp. 297-304
Author(s):  
Emre Gazyakan ◽  
Huang-Kai Kao ◽  
Ming-Huei Cheng ◽  
Holger Engel

Purpose: The differentiation of arterial versus venous occlusion in free tissue transfers has rarely been described. This study investigated changes in blood flow caused by arterial and venous occlusion and the potential for laser Doppler flowmetry to distinguish between these 2 conditions for better clinical assessment and management of free tissue transfer. Methods: Six patients with a mean age of 43.5 years underwent microsurgical free tissue transfer. The venous and arterial blood flow of the vessels and skin flap were monitored using laser Doppler flowmetry with high-frequency pulsed Doppler transducers for vessels and skin before, during, and after clamping the vessels for 10 minutes. Results: The average decreases in blood flow in the artery and vein caused by clamping were 94.4% and 93.8%, respectively. On average, arterial occlusion demonstrated a sudden drop of 67.7% and venous occlusion caused a decrease of 26.6% on laser Doppler flowmetry in free tissue skin. Conclusion: Using a vessel-holding probe, laser Doppler flowmetry could be used to differentiate between arterial and venous occlusion in free tissue transfer, thereby aiding decision-making for better clinical management.


Neurosurgery ◽  
1989 ◽  
Vol 24 (2) ◽  
pp. 166-170 ◽  
Author(s):  
E. Arbit ◽  
G. R. DiResta ◽  
R. F. Bedford ◽  
N. K. Shah ◽  
J. H. Galicich

Abstract A new technique, laser-Doppler flowmetry, has been used intraoperatively to measure blood flow responses in normal brain tissue and brain tumor to blood pressure and arterial blood gas alterations. We have observed that blood flow is reduced in most cerebral tumors, and that most tumors retain the normal response to changes in arterial blood gas; however, these responses are varied. One group of tumors in our study demonstrated an autoregulatory capacity; a second behaved passively—that is, blood flow changes followed blood pressure—while a third showed no response.


VASA ◽  
2005 ◽  
Vol 34 (4) ◽  
pp. 243-249 ◽  
Author(s):  
Drinda ◽  
Neumann ◽  
Pöhlmann ◽  
Vogelsang ◽  
Stein ◽  
...  

Background: Prostanoids are used in the treatment of Raynaud’s phenomenon and acral perfusion disorders secondary to collagenosis. In subjective terms, intravenous administration of these agents produces success in more than 50% of patients. The therapeutic outcome of clinical administration of alprostadil or iloprost may vary from individual to individual. Patients and methods: The following variables were analysed in a cross-over study in 27 patients with collagenosis and Raynaud’s phenomenon: plasma viscosity and erythrocyte aggregation (rheological variables), partial pressure of oxygen and laser Doppler flowmetry in the finger region, and lymphocyte phenotyping and interleukin (IL) determinations (immunological variables). Results: Laser Doppler flowmetry revealed significant differences between patients with secondary Raynaud’s phenomenon and a control group of 25 healthy subjects. Laser Doppler readings did not change significantly as a result of the treatments. Therapy with iloprost produced a reduction in IL-1beta, L-selectin (CD 62 L) and IL-6. Conclusion: The change in immunological variables due to iloprost may explain the long-term effects of prostaglandins in the treatment of Raynaud’s phenomenon. From our results it is not possible to infer any preference for iloprost or alprostadil.


Author(s):  
A. N. Kuks ◽  
N. V. Slivnitsyna

The results of laser Doppler flowmetry in patients with vibration disease associated with the combined effects of local and general vibration with a history of type 2 diabetes are presented.


2019 ◽  
Vol 24 (2) ◽  
pp. 108-119 ◽  
Author(s):  
B. N. Davydov ◽  
D. A. Domenyuk ◽  
S. V. Dmitrienko

Relevance. Morpho-functional changes in peripheral circulation established in type 1 diabetes mellitus correlate with changes in central hemodynamics, allowing the use of microcirculation indicators as diagnostic and prognostic criteria for assessing the degree of functional vascular disorders. Identifcation of microcirculation features of the blood by the method of laser Doppler flowmetry in children with different experience of type 1 diabetes in key age categories.Materials and methods. The study included 67 children with type 1 diabetes mellitus aged 12-15 years with an experience of the disease from six months to ten years. The comparison group consisted of 38 healthy children. The state of the microvasculature was assessed by laser Doppler flowmetry using a laser analyzer for capillary blood flow LAKK-OP.Results. In children with an experience of type 1 diabetes of less than two years, microcirculation disorders in periodontal tissues correspond to the hyperemic form, accompanied by increased perfusion, a decrease in the amplitude of low-frequency oscillations, increased heart rate, high blood flling, and blood flow bypass. For children with an endocrinopathy experience of more than three years, microcirculation disorders correspond to a stagnant form, combined with a decrease in perfusion due to stagnation of blood in the venular link, endothelial domination with suppression of neurogenic and cardiac fluctuations, low efciency and redistribution of blood flow in favor of the nutritive link.Conclusions. With the increase in experience, the degree of compensation of type 1 diabetes, the progression of diabetic microangiopathy, it is advisable to designate two stages of development of microcirculatory disorders. Early – compensatory with active adaptation, including neurogenic and endothelial regulation mechanisms. Late – decompensation with passive adaptation, supporting the effectiveness of microcirculation due to myogenic control of regulation, shunting and increasing the rate of blood outflow.


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