RESUMEN
Cocoa flavan-3-ols affect endothelium-dependent responses in resistance vessels and microcirculation has received little attention. We tested the effects of dark chocolate consumption (396 mg total flavanols/day for 3 days) in two Groups of 10 men (18-25 years; non-smokers) each comprising equal numbers of White European (WE) and South Asian (SA) ethnicity. In Group 1, dark chocolate did not affect reactive hyperaemia in forearm muscle, but augmented muscle dilatation evoked by acute mental stress, and reactive hyperaemia and acetylcholine (ACh)-evoked dilatation in cutaneous microcirculation. Conversely, in Group 2, chocolate did not affect cutaneous reactive hyperaemia or ACh-evoked dilatation, but these responses were blunted in Group 1 relative to Group 2. Further, when Groups 1 and 2 were combined, responses were blunted in SAs relative to WEs, augmented by chocolate in SAs only. In Group 2 individuals whose ACh-evoked dilatation was attenuated by nitric oxide synthase (NOS) inhibition, ACh-evoked dilatation was not altered after chocolate, but the attenuating effect of NOS inhibition was lost. Conversely, in Group 2 individuals whose ACh-evoked dilatation was enhanced by NOS inhibition, ACh-evoked dilatation was also augmented by chocolate. We propose that in resistance and microvessels of young men, cocoa flavan-3-ols preferentially augment endothelium-dependent dilator responses whose responses are depressed by familial and lifestyle factors more prevalent in SAs than Wes. Flavan-3-ols may facilitate the NOS pathway but also influence other endothelium-dependent dilators.
Asunto(s)
Cacao , Chocolate , Estilo de Vida , Microcirculación , Humanos , Masculino , Adulto Joven , Adulto , Cacao/química , Microcirculación/efectos de los fármacos , Adolescente , Flavonoides/farmacología , Vasodilatación/efectos de los fármacos , Población Blanca , Hiperemia , Endotelio Vascular/efectos de los fármacos , Piel/irrigación sanguínea , Piel/efectos de los fármacos , Piel/metabolismo , Microvasos/efectos de los fármacos , Pueblo Asiatico , Antebrazo/irrigación sanguínea , Acetilcolina/farmacología , Estrés Psicológico , Óxido Nítrico Sintasa/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismoRESUMEN
Energy drinks are nonalcoholic beverages whose main ingredients are sugar, taurine, and caffeine. The consumption of energy drinks is increasing worldwide, but only a few conflicting studies have investigated the vascular effects of energy drinks in young adults. The aim of this study was to evaluate microvascular reactivity before and after energy drinks consumption in young healthy male volunteers. This was a cross-sectional prospective study. Microvascular reactivity signals were evaluated in the skin of the forearm using laser speckle contrast imaging with acetylcholine (ACh) iontophoresis before and 90 and 180 min after the randomized consumption of one ED or the same volume of water (control), followed by a postocclusive reactive hyperemia (PORH) test. Thirty-two volunteers were evaluated (age: 25.4±4.3 years). Energy drink consumption prevented the rest-induced reduction in cutaneous vascular conductance over time that was observed in the control group. In the control group, there were significant reductions in microvascular vasodilation at 90 and 180 min compared to baseline (P=0.004), but this was not the case in the energy drink group (P=0.76). Our results demonstrated that the reduction in microvascular conductance associated with prolonged immobility can be prevented by the consumption of one energy drink, highlighting the vasodilator effects of this beverage in young individuals at rest. The between-study variability in terms of the brand of energy drinks and the ingested volume, as well as the method of vascular evaluation and the inclusion criteria, may explain the discrepancies among previous studies on the vascular effects of energy drinks.
Asunto(s)
Bebidas Energéticas , Humanos , Masculino , Adulto , Estudios Prospectivos , Estudios Transversales , Adulto Joven , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiología , Descanso/fisiología , Antebrazo/irrigación sanguínea , Microcirculación/efectos de los fármacos , Microcirculación/fisiología , Piel/irrigación sanguínea , Piel/efectos de los fármacos , Hiperemia , Microvasos/efectos de los fármacos , Acetilcolina/administración & dosificación , Acetilcolina/farmacologíaRESUMEN
BACKGROUND: Obesity is associated with resistance to the metabolic (glucose uptake) and vascular (nitric-oxide mediated dilation and microvascular recruitment) actions of insulin. These vascular effects contribute to insulin sensitivity by increasing tissue delivery of glucose. Studies by us and others suggest that sympathetic activation contributes to insulin resistance to glucose uptake. Here we tested the hypothesis that sympathetic activation contributes to impaired insulin-mediated vasodilation in adult subjects with obesity. METHODS AND RESULTS: In a randomized crossover study, we used a euglycemic hyperinsulinemic clamp in 12 subjects with obesity to induce forearm arterial vasodilation (forearm blood flow) and microvascular recruitment (contrast-enhanced ultrasonography) during an intrabrachial infusion of saline (control) or phentolamine (sympathetic blockade). Insulin increased forearm blood flow on both study days (from 2.21±1.22 to 4.89±4.21 mL/100 mL per min, P=0.003 and from 2.42±0.89 to 7.19±3.35 mL/100 mL per min, P=0.002 for the intact and blocked day, respectively). Sympathetic blockade with phentolamine resulted in a significantly greater increase in microvascular flow velocity (∆microvascular flow velocity: 0.23±0.65 versus 2.51±3.01 arbitrary intensity units (AIU/s) for saline and phentolamine respectively, P=0.005), microvascular blood volume (∆microvascular blood volume: 1.69±2.45 versus 3.76±2.93 AIU, respectively, P=0.05), and microvascular blood flow (∆microvascular blood flow: 0.28±0.653 versus 2.51±3.01 AIU2/s, respectively, P=0.0161). To evaluate if this effect was not due to nonspecific vasodilation, we replicated the study in 6 subjects with obesity comparing intrabrachial infusion of phentolamine to sodium nitroprusside. At doses that produced similar increases in forearm blood flow, insulin-induced changes in microvascular flow velocity were greater during phentolamine than sodium nitroprusside (%microvascular flow velocity=58% versus 29%, respectively, P=0.031). CONCLUSIONS: We conclude that sympathetic activation impairs insulin-mediated microvascular recruitment in adult subjects with obesity.
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Estudios Cruzados , Antebrazo , Insulina , Microcirculación , Obesidad , Fentolamina , Flujo Sanguíneo Regional , Sistema Nervioso Simpático , Vasodilatación , Humanos , Antebrazo/irrigación sanguínea , Masculino , Fentolamina/farmacología , Femenino , Obesidad/fisiopatología , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiología , Adulto , Sistema Nervioso Simpático/fisiopatología , Sistema Nervioso Simpático/efectos de los fármacos , Flujo Sanguíneo Regional/efectos de los fármacos , Microcirculación/efectos de los fármacos , Velocidad del Flujo Sanguíneo , Persona de Mediana Edad , Técnica de Clampeo de la Glucosa , Resistencia a la Insulina , Bloqueo Nervioso Autónomo/métodosRESUMEN
OBJECTIVE: Severe hand electrical injuries often occur in functional areas such as joints; the repair requires attention to both appearance and function due to the visibility of the hand. This study aimed to present the clinical experience of successfully repairing hand electrical injuries using improved forearm venous flaps. METHODS: From 2020 to 2022, 15 cases of severe hand electrical injuries were diagnosed, including 10 males and 5 females. Among them, 6 cases were repaired in the first web space, 4 in the thumb, 3 in the index finger, 2 in the middle finger, 2 in the ring finger, and 2 in the little finger. The size of venous flaps ranged from 2.0 cm × 1.8 cm to 12 cm × 4.0 cm. All patients underwent repair using improved forearm venous flaps. The follow-up period ranged from 5 to 8 months. RESULTS: All flaps survived without serious complications. All patients were satisfied with the postoperative aesthetics and function of their hands. CONCLUSION: The improved forearm venous flap is a simple and reliable method for repairing hand electrical injuries.
Asunto(s)
Traumatismos por Electricidad , Antebrazo , Traumatismos de la Mano , Colgajos Quirúrgicos , Humanos , Masculino , Femenino , Estudios Retrospectivos , Adulto , Antebrazo/cirugía , Antebrazo/irrigación sanguínea , Traumatismos de la Mano/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Colgajos Quirúrgicos/trasplante , Traumatismos por Electricidad/cirugía , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Adulto Joven , Adolescente , Venas/cirugía , Venas/lesiones , Venas/trasplante , Resultado del TratamientoRESUMEN
BACKGROUND: Consumer products such as electrical shavers exert a combination of dynamic loading in the form of pressure and shear on the skin. This mechanical stimulus can lead to discomfort and skin tissue responses characterised as "Skin Sensitivity". To minimise discomfort following shaving, there is a need to establish specific stimulus-response relationships using advanced tools such as optical coherence tomography (OCT). OBJECTIVE: To explore the spatial and temporal changes in skin morphology and microvascular function following an electrical shaving stimulus. METHODS: Ten healthy male volunteers were recruited. The study included a 60-s electrical shaving stimulus on the forearm, cheek and neck. Skin parameters were recorded at baseline, 20 min post stimulus and 24 h post stimulus. Structural and dynamic skin parameters were estimated using OCT, while transepidermal water loss (TEWL) was recorded to provide reference values for skin barrier function. RESULTS: At baseline, six of the eight parameters revealed statistically significant differences between the forearm and the facial sites, while only surface roughness (Rq) and reflectivity were statistically different (p < 0.05) between the cheek and neck. At 20 min post shaving, there was a significant increase in the TEWL values accompanied by increased blood perfusion, with varying magnitude of change dependent on the anatomical site. Recovery characteristics were observed 24 h post stimulus with most parameters returning to basal values, highlighting the transient influence of the stimulus. CONCLUSIONS: OCT parameters revealed spatial and temporal differences in the skin tissue response to electrical shaving. This approach could inform shaver design and prevent skin sensitivity.
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Piel , Tomografía de Coherencia Óptica , Humanos , Masculino , Tomografía de Coherencia Óptica/métodos , Adulto , Piel/irrigación sanguínea , Piel/diagnóstico por imagen , Antebrazo/irrigación sanguínea , Adulto Joven , Microvasos/diagnóstico por imagen , Microvasos/fisiología , Mejilla/irrigación sanguínea , Mejilla/diagnóstico por imagen , Pérdida Insensible de Agua/fisiología , Voluntarios Sanos , Fenómenos Fisiológicos de la Piel , Estimulación Eléctrica , Cuello/diagnóstico por imagen , Cuello/irrigación sanguínea , Microcirculación/fisiologíaRESUMEN
This article reports a case of a female patient admitted with swelling and subcutaneous mass in the right forearm, initially suspected to be multiple nerve fibroma. However, through preoperative imaging and surgery, the final diagnosis confirmed superficial thrombophlebitis. This condition resulted in entrapment of the radial nerve branch, leading to noticeable nerve entrapment and radiating pain. The surgery involved the excision of inflammatory tissue and thrombus, ligation of the cephalic vein, and complete release of the radial nerve branch. Postoperative pathology confirmed the presence of Superficial Thrombophlebitis. Through this case, we emphasize the importance of comprehensive utilization of clinical, imaging, and surgical interventions for more accurate diagnosis and treatment. This is the first clinical report of radial nerve branch entrapment due to superficial thrombophlebitis.
Asunto(s)
Antebrazo , Síndromes de Compresión Nerviosa , Nervio Radial , Tromboflebitis , Humanos , Femenino , Tromboflebitis/cirugía , Tromboflebitis/etiología , Tromboflebitis/diagnóstico , Síndromes de Compresión Nerviosa/etiología , Síndromes de Compresión Nerviosa/cirugía , Antebrazo/inervación , Antebrazo/irrigación sanguínea , Antebrazo/cirugía , Nervio Radial/cirugía , Neuropatía Radial/etiología , Neuropatía Radial/cirugía , Persona de Mediana EdadRESUMEN
The human forearm model is commonly employed in physiological investigations exploring local vascular function and oxygen delivery; however, the effect of arm dominance on exercising forearm hemodynamics and skeletal muscle oxygen saturation (SmO2) in untrained individuals is poorly understood. Therefore, the purpose of this study was to explore the effect of self-identified arm dominance on forearm hemodynamics and SmO2 in untrained individuals during submaximal, non-ischemic forearm exercise. Twenty healthy individuals (23±4 years, 50% female; 80% right-handed) completed three-minute bouts of supine rhythmic (1 second contraction: 2 second relaxation duty cycle) forearm handgrip exercise at both absolute (10kg; 98N) and relative (30% of maximal voluntary contraction) intensities in each forearm. Beat-by-beat measures of forearm blood flow (FBF; ml/min), mean arterial blood pressure (MAP; mmHg) and flexor digitorum superficialis SmO2 (%) were obtained throughout and averaged during the final 30 seconds of rest, exercise, and recovery while forearm vascular conductance was calculated (FVC; ml/min/100mmHg). Data are Δ from rest (mean±SD). Absolute force production did not differ between non-dominant and dominant arms (97±11 vs. 98±13 N, p = 0.606) whereas relative force production in females did (69±24 vs. 82±25 N, p = 0.001). At both exercise intensities, FBFRELAX, FVCRELAX, MAPRELAX, and the time constant tau for FBF and SmO2 were unaffected by arm dominance (all p>0.05). While arm dominance did not influence SmO2 during absolute intensity exercise (p = 0.506), the non-dominant arm in females experienced an attenuated reduction in SmO2 during relative intensity exercise (-14±10 vs. -19±8%, p = 0.026)-though exercise intensity was also reduced (p = 0.001). The present investigation has demonstrated that arm dominance in untrained individuals does not impact forearm hemodynamics or SmO2 during handgrip exercise.
Asunto(s)
Ejercicio Físico , Antebrazo , Hemodinámica , Músculo Esquelético , Humanos , Femenino , Músculo Esquelético/fisiología , Músculo Esquelético/irrigación sanguínea , Antebrazo/irrigación sanguínea , Antebrazo/fisiología , Hemodinámica/fisiología , Masculino , Ejercicio Físico/fisiología , Adulto , Adulto Joven , Fuerza de la Mano/fisiología , Brazo/fisiología , Brazo/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Oxígeno/metabolismo , Consumo de Oxígeno/fisiologíaRESUMEN
ABSTRACT: Montgomery, TR Jr, Olmos, A, Sears, KN, Succi, PJ, Hammer, SM, Bergstrom, HC, Hill, EC, Trevino, MA, and Dinyer-McNeely, TK. Influence of blood flow restriction on neuromuscular function and fatigue during forearm flexion in men. J Strength Cond Res 38(7): e349-e358, 2024-To determine the effects of blood flow restriction (BFR) on the mean firing rate (MFR) and motor unit action potential amplitude (MUAPAMP) vs. recruitment threshold (RT) relationships during fatiguing isometric elbow flexions. Ten men (24.5 ± 4.0 years) performed isometric trapezoidal contractions at 50% maximum voluntary contraction to task failure with or without BFR, on 2 separate days. For BFR, a cuff was inflated to 60% of the pressure required for full brachial artery occlusion at rest. During both visits, surface electromyography was recorded from the biceps brachii of the dominant limb and the signal was decomposed. A paired-samples t test was used to determine the number of repetitions completed between BFR and CON. ANOVAs (repetition [first, last] × condition [BFR, CON]) were used to determine differences in MFR vs. RT and MUAPAMP vs. RT relationships. Subjects completed more repetitions during CON (12 ± 4) than BFR (9 ± 2; p = 0.012). There was no significant interaction (p > 0.05) between the slopes and y-intercepts during the repetition × condition interaction for MUAPAMP vs. MFR. However, there was a main effect of repetition for the slopes of the MUAPAMP vs. RT (p = 0.041) but not the y-intercept (p = 0.964). Post hoc analysis (collapsed across condition) indicated that the slopes of the MUAPAMP vs. RT during the first repetition was less than the last repetition (first: 0.022 ± 0.003 mv/%MVC; last: 0.028 ± 0.004 mv/%MVC; p = 0.041). Blood flow restriction resulted in the same amount of higher threshold MU recruitment in approximately 75% of the repetitions. Furthermore, there was no change in MFR for either condition, even when taken to task failure. Thus, BFR training may create similar MU responses with less total work completed than training without BFR.
Asunto(s)
Electromiografía , Antebrazo , Contracción Isométrica , Fatiga Muscular , Músculo Esquelético , Flujo Sanguíneo Regional , Humanos , Masculino , Fatiga Muscular/fisiología , Adulto , Contracción Isométrica/fisiología , Antebrazo/irrigación sanguínea , Antebrazo/fisiología , Adulto Joven , Músculo Esquelético/fisiología , Músculo Esquelético/irrigación sanguínea , Flujo Sanguíneo Regional/fisiología , Terapia de Restricción del Flujo SanguíneoRESUMEN
The aim of this study was to determine the effect of posture changes on vascular compliance in intracranial (brain) versus extracranial vascular beds (forearm). Eighteen young adults (nine females) performed a supine-to-seated-to-standing protocol involving 5 min of rest in each position. Continuous blood pressure, middle cerebral artery (MCA) blood velocity, and brachial artery blood velocity were recorded at each posture. Three to five consecutive steady-state cardiac cycles at each posture were analyzed by a four-element lumped parameter modified Windkessel model to calculate vascular compliance. Mean arterial pressure (MAP) increased from supine to seated (76(9) vs. 81(12) mmHg; P = 0.006) and from supine to standing (76(9) vs. 82(13) mmHg; P = 0.034). Mean blood flow was greater in the MCA relative to the forearm (forearm: 40(5) mL·min-1, MCA: 224(17) mL·min-1; main effect P < 0.001). Conversely, vascular resistance (forearm: 3.25(0.50) mmHg-1·mL·min-1, brain: 0.36(0.04) mmHg-1·mL·min-1; main effect P < 0.001) and compliance (forearm: 0.010(0.001) mL·min-1·mmHg-1, brain: 0.005(0.001) mL·min-1·mmHg-1; main effect P = 0.001) were greater in the forearm compared to the brain. Significant main effects of posture were observed with decreasing values in upright positions for mean blood flow (P = 0.001) in both vascular beds, but not for resistance (P = 0.163) or compliance (P = 0.385). There were no significant interaction effects between vascular bed and posture for mean flow (P = 0.057), resistance (P = 0.258), or compliance (P = 0.329). This study provides evidence that under steady-state conditions, posture does not affect cerebrovascular compliance.
Asunto(s)
Circulación Cerebrovascular , Arteria Cerebral Media , Postura , Resistencia Vascular , Humanos , Femenino , Masculino , Circulación Cerebrovascular/fisiología , Adulto Joven , Postura/fisiología , Arteria Cerebral Media/fisiología , Adulto , Resistencia Vascular/fisiología , Velocidad del Flujo Sanguíneo/fisiología , Arteria Braquial/fisiología , Antebrazo/irrigación sanguínea , Sedestación , Posición Supina/fisiología , Presión Sanguínea/fisiología , Adaptabilidad , Posición de Pie , Presión ArterialRESUMEN
BACKGROUND: Arteriovenous fistula stenosis can directly lead to the formation of autologous arteriovenous fistula aneurysms (AVFAs), but the coexistence of true and pseudoaneurysms is relatively rare. The coexistence of true and pseudoaneurysms increases the risk of rupture of the arteriovenous fistula and complicates subsequent surgical intervention, potentially posing a threat to the patient's life, and thus requires significant attention. CASE PRESENTATION: The patient presented with arteriovenous fistula (AVF) after hemodialysis 6 years ago. 2 years ago, the patient presented with a mass that had formed near the left forearm arteriovenous fistula and gradually increased in size. Preoperatively, the AVF stenosis was identified as the cause of the mass formation, and the patient was operated on. First, the blood flow was controlled to reduce the pressure at the aneurysm, and then the incision was enlarged to separate the AVF anastomosis from the mass area. The stenotic segment of the true and pseudo aneurysms and cephalic vein was removed and the over-dilated proximal cephalic vein was locally narrowed and subsequently anastomosed with the proximal radial artery to create AVF. The patient was dialyzed with an internal fistula the next day and showed no clinical manifestations related to end-limb ischemia. CONCLUSION: We removed a true pseudoaneurysm in AVF and secured the patient's vascular access. This report provides an effective strategy to manage this condition.
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Aneurisma Falso , Derivación Arteriovenosa Quirúrgica , Diálisis Renal , Humanos , Aneurisma Falso/etiología , Aneurisma Falso/cirugía , Diálisis Renal/efectos adversos , Diálisis Renal/métodos , Derivación Arteriovenosa Quirúrgica/efectos adversos , Constricción Patológica , Masculino , Persona de Mediana Edad , Fallo Renal Crónico/terapia , Fallo Renal Crónico/complicaciones , Antebrazo/irrigación sanguíneaRESUMEN
Patients with heart failure with reduced ejection fraction (HFrEF) have exaggerated sympathoexcitation and impaired peripheral vascular conductance. Evidence demonstrating consequent impaired functional sympatholysis is limited in HFrEF. This study aimed to determine the magnitude of reduced limb vascular conductance during sympathoexcitation and whether functional sympatholysis would abolish such reductions in HFrEF. Twenty patients with HFrEF and 22 age-matched controls performed the cold pressor test (CPT) [left foot 2-min in -0.5 (1)°C water] alone and with right handgrip exercise (EX + CPT). Right forearm vascular conductance (FVC), forearm blood flow (FBF), and mean arterial pressure (MAP) were measured. Patients with HFrEF had greater decreases in %ΔFVC and %ΔFBF during CPT (both P < 0.0001) but not EX + CPT (P = 0.449, P = 0.199) compared with controls, respectively. %ΔFVC and %ΔFBF decreased from CPT to EX + CPT in patients with HFrEF (both P < 0.0001) and controls (P = 0.018, P = 0.015), respectively. MAP increased during CPT and EX + CPT in both groups (all P < 0.0001). MAP was greater in controls than in patients with HFrEF during EX + CPT (P = 0.025) but not CPT (P = 0.209). In conclusion, acute sympathoexcitation caused exaggerated peripheral vasoconstriction and reduced peripheral blood flow in patients with HFrEF. Handgrip exercise abolished sympathoexcitatory-mediated peripheral vasoconstriction and normalized peripheral blood flow in patients with HFrEF. These novel data reveal intact functional sympatholysis in the upper limb and suggest that exercise-mediated, local control of blood flow is preserved when cardiac limitations that are cardinal to HFrEF are evaded with dynamic handgrip exercise.NEW & NOTEWORTHY Patients with HFrEF demonstrate impaired peripheral blood flow regulation, evidenced by heightened peripheral vasoconstriction that reduces limb blood flow in response to physiological sympathoexcitation (cold pressor test). Despite evidence of exaggerated sympathetic vasoconstriction, patients with HFrEF demonstrate a normal hyperemic response to moderate-intensity handgrip exercise. Most importantly, acute, simultaneous handgrip exercise restores normal limb vasomotor control and vascular conductance during acute sympathoexcitation (cold pressor test), suggesting intact functional sympatholysis in patients with HFrEF.
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Ejercicio Físico , Antebrazo , Fuerza de la Mano , Insuficiencia Cardíaca , Volumen Sistólico , Sistema Nervioso Simpático , Vasoconstricción , Humanos , Masculino , Sistema Nervioso Simpático/fisiopatología , Femenino , Insuficiencia Cardíaca/fisiopatología , Persona de Mediana Edad , Antebrazo/irrigación sanguínea , Anciano , Flujo Sanguíneo Regional , Estudios de Casos y Controles , Función Ventricular Izquierda , Frío , Presión Arterial , DescansoRESUMEN
Brachial artery flow-mediated dilation (BAFMD) is induced by hyperemic wall shear rate (WSR) following forearm ischemia. In older adults, there appears to be a reduced brachial hyperemic WSR and altered stimulus-response relationship compared with young adults. However, it is unclear if an altered forearm microvascular response to ischemia influences brachial hyperemic WSR in older adults. We determined associations between brachial hyperemic WSR and forearm skeletal muscle oxygen saturation in young and older adults. Healthy young (n = 17, 29 ± 7 yr) and older (n = 32, 65 ± 4 yr) adults participated in the study. BAFMD by a multigate spectral Doppler system and forearm skeletal muscle oxygen saturation by near-infrared spectroscopy were concurrently measured. When compared with the young, older adults showed reduced oxygen extraction kinetics (OE, 0.15 [0.12-0.17] vs. 0.09 [0.05-0.12]%s-1) and magnitude (So2deficit, 3,810 ± 1,420 vs. 2,723 ± 1,240%s) during ischemia, as well as oxygen resaturation kinetics (So2slope, 2.5 ± 0.7 vs. 1.7 ± 0.7%s-1) upon reperfusion (all P < 0.05). When OE in the young and So2slope in older adults were stratified by their median values, young adults with OE above the median had greater hyperemic WSR parameters compared with those below the median (P < 0.05), but So2slope in older adults did not show clear differences in hyperemic WSR parameters between those above/below the median. This study demonstrates that, in addition to a reduced microvascular response to ischemia, there may be a dissociation between microvascular response to ischemia and brachial hyperemic WSR in older adults, which may result in a further impairment of BAFMD in this cohort.NEW & NOTEWORTHY Microvascular response to ischemia and subsequent reperfusion is diminished in older adults compared with the young. Furthermore, there appears to be a dissociation between the microvascular response to ischemia and brachial hyperemic WSR in older adults, which may further disturb the BAFMD process in this cohort. A reduced BAFMD in older adults may be a result of multiple alterations occurring both at macro- and microcirculation.
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Arteria Braquial , Antebrazo , Hiperemia , Microcirculación , Músculo Esquelético , Flujo Sanguíneo Regional , Vasodilatación , Humanos , Arteria Braquial/fisiopatología , Arteria Braquial/diagnóstico por imagen , Masculino , Femenino , Adulto , Anciano , Hiperemia/fisiopatología , Hiperemia/metabolismo , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/metabolismo , Persona de Mediana Edad , Antebrazo/irrigación sanguínea , Adulto Joven , Isquemia/fisiopatología , Isquemia/metabolismo , Factores de Edad , Velocidad del Flujo Sanguíneo , Espectroscopía Infrarroja Corta , Envejecimiento/metabolismo , Envejecimiento/fisiología , Consumo de Oxígeno , Saturación de Oxígeno , Microvasos/fisiopatología , Microvasos/metabolismo , Microvasos/diagnóstico por imagenRESUMEN
It is unclear whether muscle blood flow (MBF) is altered in long-term Hodgkin lymphoma (HL) survivors. We tested the hypothesis that 1) MBF response during mental stress (MS) is impaired in long-term HL survivors and 2) aerobic exercise training combined with local strength exercise (ET) restores MBF responses during MS in these survivors. Eighteen 5-year HL survivors and 10 aged-paired healthy subjects (HC) were studied. Twenty HL survivors were randomly divided into two groups: exercise-trained (HLT, n = 10) and untrained (HLUT, n = 10). Maximal aerobic capacity was evaluated by a cardiopulmonary exercise test and forearm blood flow (FBF) by venous occlusion plethysmography. MS was elicited by Stroop color and word test. ET was conducted for 4 mo, 3/wk for 60 min each session. The aerobic exercise intensity corresponded to anaerobic threshold up to 10% below the respiratory compensation point. The strength exercises consisted of two to three sets of chest press, pulley and squat exercises, 12-15 repetitions each exercise at 30-50% of the maximal voluntary contraction. Baseline was similar in HL survivors and HC, except peak oxygen consumption (peak VÌo2, P = 0.013) and FBF (P = 0.006) that were lower in the HL survivors. FBF responses during MS were lower in HL survivors (P < 0.001). ET increased peak VÌo2 (11.59 ± 3.07%, P = 0.002) and FBF at rest (33.74 ± 5.13%, P < 0.001) and during MS (24 ± 5.31%, P = 0.001). Further analysis showed correlation between the changes in peak VÌo2 and the changes in FBF during MS (r = 0.711, P = 0.001). In conclusion, long-term HL survivors have impaired MBF responses during MS. ET restores MBF responses during MS.NEW & NOTEWORTHY Long-term Hodgkin lymphoma (HL) survivors have impaired muscle blood flow responses during mental stress and decreased maximal aerobic capacity. Supervised aerobic exercise training combined with local strength exercises restores muscle blood flow responses during mental stress and maximal aerobic capacity in these survivors. These findings provide evidence of safety and effectiveness of exercise training in HL survivors. Moreover, they highlight the importance of exercise training in the treatment of this set of patients.
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Supervivientes de Cáncer , Tolerancia al Ejercicio , Enfermedad de Hodgkin , Músculo Esquelético , Consumo de Oxígeno , Flujo Sanguíneo Regional , Entrenamiento de Fuerza , Humanos , Enfermedad de Hodgkin/fisiopatología , Enfermedad de Hodgkin/terapia , Masculino , Femenino , Adulto , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/fisiopatología , Persona de Mediana Edad , Ejercicio Físico , Factores de Tiempo , Antebrazo/irrigación sanguínea , Terapia por Ejercicio/métodos , Capacidad CardiovascularRESUMEN
Skin blood flow is commonly determined by laser Doppler flowmetry (LDF). It has been suggested that pathophysiological conditions can be assessed by analysis of specific frequency domains of the LDF signals. We tested whether physiological stimuli that activate myogenic and neurogenic mechanisms would affect relevant portions of the laser Doppler spectrum. LDF sensors were placed on the right forearm of 14 healthy volunteers for myogenic (six females) and 13 for neurogenic challenge (five females). Myogenic responses were tested by positioning the arm â¼50° above/below heart level. Neurogenic responses were tested by immersing the left hand into an ice slurry with and without topical application of local anaesthetic. Short-time Fourier analyses were computed over the range of 0.06 to 0.15 Hz for myogenic and 0.02 to 0.06 Hz for neurogenic. No significant differences in spectral density were observed (P = 0.40) in the myogenic range with arm above (7 ± 54 × 10-4 dB) and below heart (7 ± 14 × 10-4 dB). Neurogenic spectral density showed no significant increase from baseline to cold pressor test (0.0017 ± 0.0013 and 0.0038 ± 0.0039 dB; P = 0.087, effect size 0.47). After application of anaesthetic, neurogenic spectral density was unchanged between the baseline and cold pressor test (0.0014 ± 0.0025 and 0.0006 ± 0.0005 dB; P = 0.173). These results suggest that changes in the myogenic and neurogenic spectral density of LDF signals did not fully reflect the skin vascular function activated by pressure manipulation and sympathetic stimulation. Therefore, LDF myogenic and neurogenic spectral density data should be interpreted with caution.
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Flujometría por Láser-Doppler , Flujo Sanguíneo Regional , Piel , Sistema Nervioso Simpático , Humanos , Femenino , Piel/irrigación sanguínea , Masculino , Adulto , Flujometría por Láser-Doppler/métodos , Flujo Sanguíneo Regional/fisiología , Sistema Nervioso Simpático/fisiología , Adulto Joven , Antebrazo/irrigación sanguínea , Frío , Presión , Anestésicos Locales/farmacología , Anestésicos Locales/administración & dosificación , Presión Sanguínea/fisiologíaRESUMEN
PURPOSE: Atherosclerotic disease of the forearm arteries can impede the maturation of distal fistulas in diabetic patients. The goal of this study was to look at the maturity of diabetic hemodialysis patients' distal forearm (radiocephalic snuffbox or distal forearm) arteriovenous fistulas. MATERIALS AND METHODS: Patients with chronic renal failure who were candidates for distal forearm radiocephalic arteriovenous fistula implantation were evaluated in this cross-sectional study. Patients' demographic details, underlying disorders, laboratory measurements, vital signs, and information on their surgery were all noted. Patients were checked for fistula development 1 week, 1 month, 2 months, and then monthly until 6 months after surgery. Arteriovenous fistula maturation characterized by optimal blood flow, vessel dilation, and structural adaptations. RESULTS: Among 343 patients (56% male, 44% female, mean age: 57.32 ± 12.48 years), hypertension prevailed (81.9%), followed by hyperlipidemia (42.3%) and coronary artery disease history (25.9%). AVFs achieved 58.3% maturation in 64.98 ± 11.05 days; higher BP during creation correlated with successful maturation (17.02 ± 1.46 mmHg vs 13.90 ± 1.93 mmHg, P < .05). No significant statistical difference found in distal forearm arteriovenous fistula maturation between males (57.8%) and females (58.9%) (P > .005). However, 41.7% of AVFs failed in 18.83 ± 17.89 days. Failed AVFs exhibited lower BP during operation and failure (11.75 ± 1.86 mmHg). Kaplan-Meier analysis depicted maturation probabilities over 90 days post-surgery. CONCLUSION: Diabetes and patient sex did not affect the maturation time of distal forearm AVFs in hemodialysis patients. Increased blood pressure during and after surgery correlated with shorter maturation time.
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Derivación Arteriovenosa Quirúrgica , Nefropatías Diabéticas , Antebrazo , Fallo Renal Crónico , Diálisis Renal , Grado de Desobstrucción Vascular , Humanos , Masculino , Femenino , Derivación Arteriovenosa Quirúrgica/efectos adversos , Persona de Mediana Edad , Antebrazo/irrigación sanguínea , Anciano , Resultado del Tratamiento , Factores de Tiempo , Estudios Transversales , Fallo Renal Crónico/terapia , Fallo Renal Crónico/diagnóstico , Nefropatías Diabéticas/terapia , Nefropatías Diabéticas/fisiopatología , Nefropatías Diabéticas/etiología , Adulto , Factores de Riesgo , Flujo Sanguíneo Regional , Arteria Radial/cirugía , Arteria Radial/fisiopatología , Arteria Radial/diagnóstico por imagenRESUMEN
OBJECTIVES: To explore the clinical application and efficacy of transplantation of free composite flaps supplied by radial osteocutaneous branch of the dorsal branch of the anterior interosseous artery for reconstructing bone and skin defects in the hand. MATERIAL AND METHODS: Anatomically, the radial osteocutaneous branch of the dorsal branch of the anterior interosseous artery has constant collateral anastomoses which can provide a large dorsoradial flap from the dorsum of the forearm. This flap was used for reconstruction in five cases of cutaneous and phalangeal defects. RESULTS: Reconstruction was successful in all five cases, with consolidated phalanx and good cosmetic results. All donor sites could be closed directly. CONCLUSION: Reconstruction with dorsoradial forearm flaps is a reliable procedure which causes minimal trauma. Thus, it is an ideal approach for repairing cutaneous and phalangeal defects.
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Colgajos Tisulares Libres , Humanos , Antebrazo/cirugía , Antebrazo/irrigación sanguínea , Colgajos Tisulares Libres/irrigación sanguínea , Traumatismos de la Mano/cirugía , Procedimientos de Cirugía Plástica/métodos , Arteria Radial/trasplanteRESUMEN
AIMS: The aim was to investigate the relationship between microvascular function, cardiovascular risk profile, and subclinical atherosclerotic burden. METHODS AND RESULTS: The study enrolled 3809 individuals, 50-65 years old, participating in the population-based observational cross-sectional Swedish CArdioPulmonary bioImage Study. Microvascular function was assessed in forearm skin using an arterial occlusion and release protocol determining peak blood oxygen saturation (OxyP). Cardiovascular risk was calculated using the updated Systematic Coronary Risk Evaluation [SCORE2; 10-year risk of fatal and non-fatal cardiovascular disease (CVD) events]. The OxyP was compared with coronary artery calcification score (CACS) and to plaques in the carotid arteries. Individuals with OxyP values in the lowest quartile (Q1; impaired microvascular function) had a mean SCORE2 of 5.8% compared with 3.8% in those with the highest values of OxyP (Q4), a relative risk increase of 53%. The risk of having a SCORE2 > 10% was five times higher for those in Q1 (odds ratio: 4.96, 95% confidence interval: 2.76-8.93) vs. Q4 when adjusting for body mass index and high-sensitivity C-reactive protein. The OxyP was lower in individuals with CACS > 0 and in those with both carotid plaques and CACS > 0, compared with individuals without subclinical atherosclerotic burdens (87.5 ± 5.6% and 86.9 ± 6.0%, vs. 88.6 ± 5.8%, P < 0.01). CONCLUSION: In a population without CVD or diabetes mellitus, impaired microvascular function is associated with cardiovascular risk profiles such as higher SCORE2 risk and CACS. We suggest that OxyP may serve as a microcirculatory functional marker of subclinical atherosclerosis and CVD risk that is not detected by structural assessments.
Impaired microvascular function was associated with higher cardiovascular risk profile SCORE2 and subclinical atherosclerotic burden defined by carotid plaque and coronary artery calcification score (CACS).Individuals with impaired microvascular function (peak oxygen saturation in the forearm skin, OxyP, after a prolonged arterial occlusion provocation) had a moderate risk level of SCORE2 compared to low risk level in those with the highest values of OxyP.The OxyP was lower in individuals with CACS > 0 and in those with both carotid plaques and CACS > 0, compared with individuals with carotid plaque only and in individuals without subclinical atherosclerotic burdens.
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Enfermedades de las Arterias Carótidas , Factores de Riesgo de Enfermedad Cardiaca , Microcirculación , Humanos , Persona de Mediana Edad , Masculino , Femenino , Suecia/epidemiología , Estudios Transversales , Anciano , Medición de Riesgo , Enfermedades de las Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/epidemiología , Saturación de Oxígeno , Placa Aterosclerótica , Enfermedades Asintomáticas , Calcificación Vascular/fisiopatología , Calcificación Vascular/epidemiología , Antebrazo/irrigación sanguínea , Factores de Riesgo , Piel/irrigación sanguínea , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/diagnóstico , Factores de EdadRESUMEN
OBJECTIVE: Although forearm arteriovenous fistulas (AVFs) are the preferred initial vascular access for hemodialysis based on national guidelines, there are no population-level studies evaluating trends in creation of forearm vs upper arm AVFs and arteriovenous grafts (AVGs). The purpose of this study was to report temporal trends in first-time permanent hemodialysis access type, and to assess the effect of national initiatives on rates of AVF placement. METHODS: Retrospective cross-sectional study (2012-2022) utilizing the Vascular Quality Initiative database. All patients older than 18 years with creation of first-time upper extremity surgical hemodialysis access were included. Anatomic location of the AVF or AVG (forearm vs upper arm) was defined based on inflow artery, outflow vein, and presumed cannulation zone. Primary analysis examined temporal trends in rates of forearm vs upper arm AVFs and AVGs using time series analyses (modified Mann-Kendall test). Subgroup analyses examined rates of access configuration stratified by age, sex, race, dialysis, and socioeconomic status. Interrupted time series analysis was performed to assess the effect of the 2015 Fistula First Catheter Last initiative on rates of AVFs. RESULTS: Of the 52,170 accesses, 57.9% were upper arm AVFs, 25.2% were forearm AVFs, 15.4% were upper arm AVGs, and 1.5% were forearm AVGs. From 2012 to 2022, there was no significant change in overall rates of forearm or upper arm AVFs. There was a numerical increase in upper arm AVGs (13.9 to 18.2 per 100; P = .09), whereas forearm AVGs significantly declined (1.8 to 0.7 per 100; P = .02). In subgroup analyses, we observed a decrease in forearm AVFs among men (33.1 to 28.7 per 100; P = .04) and disadvantaged (Area Deprivation Index percentile ≥50) patients (29.0 to 20.7 per 100; P = .04), whereas female (17.2 to 23.1 per 100; P = .03), Black (15.6 to 24.5 per 100; P < .01), elderly (age ≥80 years) (18.7 to 32.5 per 100; P < .01), and disadvantaged (13.6 to 20.5 per 100; P < .01) patients had a significant increase in upper arm AVGs. The Fistula First Catheter Last initiative had no effect on the rate of AVF placement (83.2 to 83.7 per 100; P=.37). CONCLUSIONS: Despite national initiatives to promote autogenous vascular access, the rates of first-time AVFs have remained relatively constant, with forearm AVFs only representing one-quarter of all permanent surgical accesses. Furthermore, elderly, Black, female, and disadvantaged patients saw an increase in upper arm AVGs. Further efforts to elucidate factors associated with forearm AVF placement, as well as potential physician, center, and regional variation is warranted.
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Derivación Arteriovenosa Quirúrgica , Bases de Datos Factuales , Antebrazo , Diálisis Renal , Humanos , Derivación Arteriovenosa Quirúrgica/tendencias , Derivación Arteriovenosa Quirúrgica/estadística & datos numéricos , Diálisis Renal/tendencias , Femenino , Masculino , Estudios Retrospectivos , Estudios Transversales , Persona de Mediana Edad , Anciano , Factores de Tiempo , Antebrazo/irrigación sanguínea , Estados Unidos , Resultado del Tratamiento , Implantación de Prótesis Vascular/tendencias , Implantación de Prótesis Vascular/efectos adversos , Factores de Riesgo , Adulto , Extremidad Superior/irrigación sanguínea , Pautas de la Práctica en Medicina/tendencias , Análisis de Series de Tiempo InterrumpidoRESUMEN
BACKGROUND: This study aims to compare patency rates of the 0- and 30-s (sec) balloon dilation time in hemodialysis (HD) patients with restenosis after percutaneous transluminal angioplasty (PTA). METHODS: The patients who underwent PTA within 6 months for failed arteriovenous fistula at the forearm were randomly assigned the 0-s or 30-s dilation time group. Effect of dilation time on the 3- and 6-month patency rates after PTA was examined. RESULTS: Fifty patients were enrolled in this study. The 3-month patency rate in the 30-s dilation group was better than that in the 0-s dilation group (P = 0.0050), while the 6-month patency rates did not show a significant difference between the two groups (P = 0.28). Cox's proportional hazard model revealed that 30-s of inflation time (hazard ratio 0.027; P = 0.0072), diameter of the proximal (hazard ratio 0.32; P = 0.031), and dilation pressure (hazard ratio 0.63; P = 0.014) were associated with better 3-month patency. Dilation pressure between previous and present PTA did not differ in the 0-s (P = 0.15) and 30-s dilation groups (P = 0.16). The 6-month patency rate of the present PTA in the 30-s dilation group was higher than that of the previous PTA (P = 0.015). The visual analog scale did not differ between the two groups (P = 0.51). CONCLUSION: The presenting data suggest that 30-s dilation potentially results in a better 3-month patency rate than 0-s dilation in HD patients with restenosis after PTA.