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1.
Adv Exp Med Biol ; 1232: 3-9, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893387

RESUMEN

Neonates with hypoxic-ischaemic (HI) brain injury were monitored using a broadband near-infrared spectroscopy (NIRS) system in the neonatal intensive care unit. The aim of this work is to use the NIRS cerebral oxygenation data (HbD = oxygenated-haemoglobin - deoxygenated-haemoglobin) combined with arterial saturation (SaO2) from pulse oximetry to calculate cerebral blood flow (CBF) based on the oxygen swing method, during spontaneous desaturation episodes. The method is based on Fick's principle and uses HbD as a tracer; when a sudden change in SaO2 occurs, the change in HbD represents a change in tracer concentration, and thus it is possible to estimate CBF. CBF was successfully calculated with broadband NIRS in 11 HIE infants (3 with severe injury) for 70 oxygenation events on the day of birth. The average CBF was 18.0 ± 12.7 ml 100 g-1 min-1 with a range of 4 ml 100 g-1 min-1 to 60 ml 100 g-1 min-1. For infants with severe HIE (as determined by magnetic resonance spectroscopy) CBF was significantly lower (p = 0.038, d = 1.35) than those with moderate HIE on the day of birth.


Asunto(s)
Lesiones Encefálicas , Encéfalo , Circulación Cerebrovascular , Oximetría , Oxígeno , Espectroscopía Infrarroja Corta , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Lesiones Encefálicas/diagnóstico por imagen , Humanos , Recién Nacido , Oximetría/instrumentación , Oximetría/métodos , Oxígeno/metabolismo
2.
Adv Exp Med Biol ; 1232: 11-17, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893388

RESUMEN

In the adult brain, it is well known that increases in local neural activity trigger changes in regional blood flow and, thus, changes in cerebral energy metabolism. This regulation mechanism is called neurovascular coupling (NVC). It is not yet clear to what extent this mechanism is present in the premature brain. In this study, we explore the use of transfer entropy (TE) in order to compute the nonlinear coupling between changes in brain function, assessed by means of EEG, and changes in brain oxygenation, assessed by means of near-infrared spectroscopy (NIRS). In a previous study, we measured the coupling between both variables using a linear model to compute TE. The results indicated that changes in brain oxygenation were likely to precede changes in EEG activity. However, using a nonlinear and nonparametric approach to compute TE, the results indicate an opposite directionality of this coupling. The source of the different results provided by the linear and nonlinear TE is unclear and needs further research. In this study, we present the results from a cohort of 21 premature neonates. Results indicate that TE values computed using the nonlinear approach are able to discriminate between neonates with brain abnormalities and healthy neonates, indicating a less functional NVC in neonates with brain abnormalities.


Asunto(s)
Encéfalo , Acoplamiento Neurovascular , Espectroscopía Infrarroja Corta , Adulto , Encéfalo/fisiopatología , Encefalopatías/diagnóstico , Encefalopatías/fisiopatología , Electroencefalografía , Entropía , Humanos , Recién Nacido , Acoplamiento Neurovascular/fisiología
3.
Adv Exp Med Biol ; 1232: 33-38, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893391

RESUMEN

Monitoring of cerebral tissue oxygen saturation (StO2) by near-infrared spectroscopy (NIRS oximetry) has great potential to reduce the incidence of hypoxic and hyperoxic events and thus prevent long-term disabilities in preterm neonates. Since the light has to penetrate superficial layers (bone, skin and cerebrospinal fluid) before it reaches the brain, the question arises whether these layers influence cerebral StO2 measurement. We assessed this influence on the accuracy of cerebral StO2 values. For that purpose, we simulated light propagation with 'N-layered medium' software. It was found that with a superficial layer thickness of ≤6 mm, typical for term and preterm neonates, StO2 accurately reflects cerebral tissue oxygenation.


Asunto(s)
Oximetría , Oxígeno , Cráneo , Encéfalo/metabolismo , Humanos , Hipoxia/diagnóstico , Recién Nacido , Oximetría/normas , Cráneo/anatomía & histología , Espectroscopía Infrarroja Corta
4.
Adv Exp Med Biol ; 1232: 77-83, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893397

RESUMEN

Instantaneous orthostatic hypotension (INOH) is one of the main types of orthostatic dysregulation in children and adolescents. In patients with INOH arterial pressure drops considerably after active standing and is slow to recover. We investigated changes in cerebral oxygenation in the bilateral prefrontal cortex during an active standing test in juvenile INOH patients to evaluate changes in cerebral oxygen metabolism. We enrolled 82 INOH patients (mean age 13.8 ± 2.2 years, 52 mild and 30 severe patients) at Nihon University Itabashi Hospital from October 2013 to April 2018. We measured cerebral oxygenated hemoglobin, deoxygenated hemoglobin, and total hemoglobin levels in the bilateral prefrontal cortex using near-infrared spectroscopy during an active standing test. In severe INOH patients, cerebral oxygenation of the right prefrontal cortex remained constant when blood pressure dropped; however, de-oxy-Hb significantly increased. These findings confirm that there is asymmetrical autoregulation between the right and left prefrontal cortex.


Asunto(s)
Circulación Cerebrovascular , Hipotensión Ortostática , Adolescente , Circulación Cerebrovascular/fisiología , Niño , Homeostasis , Humanos , Hipotensión Ortostática/fisiopatología , Oxihemoglobinas , Espectroscopía Infrarroja Corta
5.
Adv Exp Med Biol ; 1232: 85-90, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893398

RESUMEN

Delayed orthostatic hypotension (OH) is a minor subset of orthostatic dysregulation (OD). Cerebral blood oxygenation in juvenile patients with delayed OH has not been studied. We investigated the bilateral changes in cerebral oxygenation in the prefrontal cortex during an active standing test in 23 juvenile patients with delayed OH using near-infrared spectroscopy (NIRS). We measured the oxy-Hb, deoxy-Hb, and total-Hb during the active standing test. Four observations were made during the test: t1 in a resting supine position, t2 when maintaining blood pressure, and the remaining two (t3, t4) during hypotension. The concentration of oxy-Hb significantly decreased prior to satisfying the diagnostic criteria of delayed OH after standing and did not change thereafter. The concentration of deoxy-Hb increased gradually during the measurement periods. In addition, total-Hb increased from t2 to t3. There was no significant difference in the change in each Hb parameter between the left and right cerebral hemispheres. Our results indicate that NIRS parameters are more sensitive than blood pressure for the interpretation of cerebral autoregulation in juvenile patients with delayed OH.


Asunto(s)
Sistema Cardiovascular , Circulación Cerebrovascular , Hipotensión Ortostática , Oxígeno , Posición de Pie , Adolescente , Presión Sanguínea , Circulación Cerebrovascular/fisiología , Humanos , Hipotensión Ortostática/sangre , Hipotensión Ortostática/diagnóstico , Oxígeno/sangre , Espectroscopía Infrarroja Corta
6.
Adv Exp Med Biol ; 1232: 99-104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893400

RESUMEN

The incidence of stress-induced psychological and somatic diseases has been increasing rapidly, and it is important to clarify the neurophysiological mechanisms of stress response in order to establish effective stress management methods. We previously reported that the prefrontal cortex (PFC) plays an important role in stress response. In the present study, we employed near-infrared spectroscopy (NIRS) and electroencephalography (EEG) to investigate the characteristics of PFC activity during mental arithmetic tasks. A two-channel NIRS device was used to measure hemoglobin (Hb) concentration changes in the bilateral PFC during a mental arithmetic task (2 min) in normal adults. Simultaneously, EEG was used to also measure bilateral PFC activity during the same task. We evaluated concentration changes of oxy-Hb induced by the task while analyzing α wave changes using power spectrum analysis. It was observed that oxy-Hb in the bilateral PFC increased significantly during the task (p < 0.05), while α wave power in the PFC decreased significantly (p < 0.01). The present results indicate that mental stress tasks caused the activation of the bilateral PFC. Simultaneous measurements of NIRS and EEG are useful for evaluating the neurophysiological mechanism of stress responses in the brain.


Asunto(s)
Electroencefalografía , Fenómenos Electromagnéticos , Oxígeno , Espectroscopía Infrarroja Corta , Estrés Psicológico , Adulto , Hemoglobinas/análisis , Humanos , Oxígeno/sangre , Oxihemoglobinas/análisis , Corteza Prefrontal/fisiopatología , Estrés Psicológico/fisiopatología
7.
Adv Exp Med Biol ; 1232: 105-112, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893401

RESUMEN

BACKGROUND: We have repeatedly observed a right-left asymmetry (RLA) of prefrontal cerebral oxygenation of subjects during the resting state. AIM: To clarify if the RLA is a reliably observable phenomenon at the group level and whether it is associated with systemic physiology, absolute tissue oxygen saturation (StO2) or total hemoglobin concentration ([tHb]). MATERIAL AND METHODS: StO2 and [tHb] values at the right and left prefrontal cortex (PFC) were calculated for two 5- min resting phases based on data from 76 single measurements (24 healthy adults, aged 22.0 ± 6.4 years). StO2 and [tHb] were measured with an ISS OxiplexTS frequency domain near-infrared spectroscopy device. In addition, end-tidal CO2 (PETCO2), heart rate (HR), respiration rate (RR) and the pulse-respiration quotient (PRQ = HR/RR) were measured and analyzed for the two phases. RESULTS: On the group level it was found that i) StO2 was higher at the right compared to the left PFC (for both phases), ii) RLA of StO2 (∆StO2 = StO2 (right)-StO2 (left) was independent of PETCO2, HR and PRQ, and iii) ∆StO2 was associated with absolute StO2 and [tHb] values (positively and negatively, respectively). DISCUSSION AND CONCLUSION: This study shows that i) RLA of StO2 at the PFC is a real phenomenon, and that ii) ∆StO2 at the group level does not depend on PETCO2, HR, RR or PRQ, but on absolute StO2 and [tHb]. We conclude that the RLA is a real effect, independent of systemic physiology, and most likely reflects genuine properties of the brain, i.e. different activity states of the two hemispheres.


Asunto(s)
Hemoglobinas , Oxígeno , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Adolescente , Adulto , Hemoglobinas/metabolismo , Humanos , Oxígeno/metabolismo , Consumo de Oxígeno , Corteza Prefrontal/metabolismo , Adulto Joven
8.
Adv Exp Med Biol ; 1232: 121-127, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893403

RESUMEN

Changes in NIRS signals are related to changes in local cerebral blood flow or oxy-Hb concentration. On the other hand, recent studies have revealed the effect of chewing gum on cognitive performance, stress control etc. which accompanied brain activity in the prefrontal cortex (PFC). However, these relationships are still controversial. To evaluate the chewing effect on PFC, NIRS seems to be a suitable method of imaging such results. When measuring NIRS on PFC, blood volume in superficial tissues (scalp, skin, muscle) might have some affect. The aim of the present study was to clarify the effect of the anterior temporal muscle on NIRS signals during gum chewing. Eight healthy volunteers participated. Two-channel NIRS (HOT-1000, NeU, Japan), which can distinguish total-Hb concentrations in deep tissue and superficial tissue layers, was used. In addition to a conventional optode separation distance of 3.0 cm, Hot 1000 has a short distance of 1.0 cm (NEAR channel) to measure NIRS signals that originate exclusively from surface tissues. NIRS probes were placed at Fp1 and Fp2 in the normal probe setting. The headset was displaced to the left in order to allow the left probe to be placed over the left anterior temporal muscle. In the normal setting, the superficial signal curve shows no notable change; however, the neural (calculated and defined in HOT-1000) and deep curves show an increase during the gum chewing task. At the deviated setting, all three signals show marked changes during the task. Total-Hb concentration in the deviated probe setting is significantly large (p < 0.05) than that of in the normal probe setting. When using gum chewing as a task, it would be better to consider a probe position carefully so that the influence of muscle activity on NIRS signal can be distinguished.


Asunto(s)
Masticación , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Adulto , Hemoglobinas/metabolismo , Humanos , Japón , Proyectos Piloto , Corteza Prefrontal/fisiología , Adulto Joven
9.
Adv Exp Med Biol ; 1232: 193-199, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893410

RESUMEN

Measurement of oxyhemoglobin (O2Hb) changes in the cerebral cortex using near-infrared spectroscopy (NIRS) shows that its levels increase during moderate-intensity exercise and persists after exercise. However, the effects of exercise duration on O2Hb persistence in the premotor cortex (PMC) are unknown. We aimed to determine the effects of exercise duration on the persistence of O2Hb changes after moderate-intensity cycling as exercise. Healthy young volunteers were recruited to participate in this study. After a 3-min rest period, the exercise was initiated at a workload corresponding to 50% VO2peak. The exercise continued for 10 min and 20 min, followed by 15 min of rest. The O2Hb levels in the right (R-PMC) and left premotor cortices (L-PMC) were measured using an NIRS system. The O2Hb values during the 15-min post-exercise rest period in the R-PMC were 0.010 ± 0.011 mM·cm after the 10-min exercise and 0.035 ± 0.010 mM·cm after the 20-min exercise, without significant differences (p = 0.104). The O2Hb value in the L-PMC during post-exercise rest (0.055 ± 0.010 mM·cm) after the 20-min exercise was significantly higher than that after the 10-min exercise (0.023 ± 0.007 mM·cm; p = 0.014). Thus, the effects of exercise duration on O2Hb persistence have laterality in the PMC.


Asunto(s)
Ejercicio , Corteza Motora , Consumo de Oxígeno , Oxihemoglobinas , Espectroscopía Infrarroja Corta , Adulto , Femenino , Humanos , Masculino , Corteza Motora/metabolismo , Oxihemoglobinas/metabolismo , Factores de Tiempo , Adulto Joven
10.
Adv Exp Med Biol ; 1232: 209-214, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893412

RESUMEN

Cognitive function is reported to improve by moderate aerobic exercise. However, the effects of intermittent exercise with rest between the moderate-intensity exercise are unclear. Therefore, this study aimed to compare the effects of continuous and intermittent exercise on cerebral oxygenation and cognitive function. This study included 18 healthy adults. For the continuous exercise protocol, 5 min of rest was followed by 30 min of exercise; 5 min of rest was allowed after each exercise. For the intermittent exercise protocol, 3 sets of 10 min of exercise were completed, with 5 min of rest between the sets. Exercise intensity was 50% of maximum oxygen uptake. Oxyhemoglobin (O2Hb) in the prefrontal cortex (PFC) was measured during each protocol, and cognitive tasks (Stroop test) were performed before and after exercise. O2Hb levels for the left and right PFCs were significantly higher post-exercise than pre-exercise for both exercise protocols (p < 0.01). The average reaction time in the Stroop test was significantly shorter post-exercise than pre-exercise for both protocols (p < 0.01). There was no significant difference in the error rate pre- and post-exercise for both protocols (continuous p = 0.22; intermittent p = 0.44). There was no significant difference between both protocols in all measurement results (O2Hb: p = 0.67; average reaction time p = 0.50; error rate p = 0.24). O2Hb was higher and average reaction time was shorter after exercise than before exercise for both exercise protocols. Intermittent and continuous exercise may improve cognitive function to the same degree after exercise.


Asunto(s)
Cerebro , Cognición , Ejercicio , Oxígeno , Espectroscopía Infrarroja Corta , Adulto , Cerebro/metabolismo , Cognición/fisiología , Humanos , Oxígeno/metabolismo , Consumo de Oxígeno
11.
Adv Exp Med Biol ; 1232: 231-237, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893415

RESUMEN

Near-infrared spectroscopy (NIRS) during cardiopulmonary exercise test (CPX) has shown a correlation between prefrontal cortex (PFC) oxygenated hemoglobin (O2Hb) level and negative affective responses. We hypothesized that O2Hb changes differ between the PFC and motor-related areas. This study investigated changes in hemoglobin levels in the PFC and motor-related areas during CPX. Twelve young healthy adults participated in this study. They performed a CPX after 4 min of rest and 4 min of warming up. Cortical O2Hb, deoxygenated hemoglobin (HHb), and total hemoglobin (THb) levels were measured with NIRS during CPX. Regions of interest (ROI) were the PFC, premotor area (PMA), supplementary motor area (SMA), and primary motor cortex (M1). The anaerobic threshold (AT), respiratory compensation (RC), and peak oxygen uptake (Peak) points were determined. The rest, AT, RC and Peak points of O2Hb, HHb, and THb were averaged over 5 s; hemoglobin slopes, from RC to the Peak points, were calculated to compare functional changes in cortical oxygenation. Average values of O2Hb, HHb, and THb in each ROI were compared among the rest, AT, RC, and Peak points. Average values of hemoglobin slopes, from RC to Peak points, were compared among ROIs using Bonferroni multiple comparisons. The HHb of all ROIs significantly increased at Peak point, compared with at the AT point. THb of the PFC, PMA, and SMA significantly increased at the RC or Peak points, compared with at the rest point. Hemoglobin slopes, from RC to Peak, showed no significant differences among ROIs. Each ROI exhibited similar changes, regardless of cortical function.


Asunto(s)
Corteza Motora , Oxígeno , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Adulto , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Corteza Motora/metabolismo , Oxígeno/metabolismo , Consumo de Oxígeno , Oxihemoglobinas/metabolismo , Corteza Prefrontal/metabolismo , Adulto Joven
12.
Adv Exp Med Biol ; 1232: 239-244, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893416

RESUMEN

Near-infrared time-resolved spectroscopy (NIRTRS) can quantitatively evaluate mean optical path length (MPL). Since an increase in optical absorbers in the NIR region (e.g. an increase in deoxygenated hemoglobin during exercise) would shorten the MPL, the NIRS measurement area may vary depending on physical and physiological characteristics of the measurement region and/or the exercise intensity. The aim of this study was to examine the changes in MPL measured by NIRTRS during ramp cycling exercise between fat layer thickness-matched subjects with different aerobic capacities. Healthy control (CON, n = 8) and endurance-trained males (TR, n = 8) performed ramp cycling exercise until exhaustion. Deoxygenated hemoglobin concentration (Deoxy-Hb), total hemoglobin concentration (Total-Hb) and oxygenated hemoglobin concentration (Oxy-Hb) were evaluated by a three-wavelength NIRTRS system. MPL in each wavelength (MPL760, MPL800 and MPL830) was monitored continuously. With increasing exercise intensity, Total- and Deoxy-Hb significantly increased and Oxy-Hb decreased in both groups. Total- and Oxy-Hb during exercise were significantly higher in TR than CON (P < 0.05, P < 0.01, respectively). Furthermore, Deoxy-Hb also tended to be higher in TR than CON (P = 0.07). In addition, MPL at all wavelengths significantly shortened with an increase in exercise intensity, with no differences between CON and TR. In particular, MPL760 at peak exercise shortened more than 10% compared to the start of exercise in both groups, even though MPL830 decreased only a few per cent. These findings suggest that the NIRS measurement area may be reduced during ramp cycling exercise due to shortened MPL. Additionally, the changes in MPL may be especially greater at 760 nm than at the other wavelengths due to greater changes in Deoxy-Hb during exercise. Furthermore, this study indicates that the measurements of muscle deoxygenation using continuous-wave NIRS can be less accurate since they are significantly affected by changes in the optical path length.


Asunto(s)
Ejercicio , Consumo de Oxígeno , Músculo Cuádriceps , Adolescente , Adulto , Estudios de Casos y Controles , Prueba de Esfuerzo , Humanos , Masculino , Oxígeno/metabolismo , Oxihemoglobinas/metabolismo , Músculo Cuádriceps/metabolismo , Espectroscopía Infrarroja Corta , Adulto Joven
13.
Adv Exp Med Biol ; 1232: 245-251, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893417

RESUMEN

Skeletal muscle metabolic function is known to respond positively to endurance exercise interventions, such as marathon training. Studies investigating skeletal muscle have typically used muscle biopsy samples or magnetic resonance spectroscopy (MRS) to interrogate metabolic function. We aimed to non-invasively detect exercise-training-induced improvements in muscle function using broadband near-infrared spectroscopy (NIRS). We used NIRS to determine concentration changes in oxygenated haemoglobin (HbO2) and the oxidation state of cytochrome-c-oxidase (oxCCO) in gastrocnemius during arterial occlusion in 14 volunteers. We also used a cardio-pulmonary exercise test (CPET) to assess peak total body oxygen uptake (peakVO2; a measure of fitness). Measurements were made at baseline (BL) which was prior to a period of at least 16 weeks of training for the 2017 London Marathon, and then within 3 weeks after completion of the marathon, follow-up (FU). We observed an increase in locally measured muscle oxygen consumption and rate of oxCCO concentration change, but not in cardio-respiratory fitness measured as whole-body peak oxygen consumption (peakVO2).


Asunto(s)
Músculo Esquelético , Consumo de Oxígeno , Carrera , Espectroscopía Infrarroja Corta , Adulto , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Humanos , Masculino , Músculo Esquelético/metabolismo , Oxihemoglobinas/metabolismo
14.
Adv Exp Med Biol ; 1232: 253-259, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893418

RESUMEN

BACKGROUND: Near-infrared spectroscopy (NIRS) tissue oximeters enable non-invasive measurement of muscle oxygenation and perfusion. Several NIRS oximeters are currently available, particularly for muscle measurements. AIM: To evaluate the agreement of oxygenation and perfusion measurements obtained by two devices (Moxy, Fortiori Designs LLC, USA, and Nimo, Nirox, Italy) during an arterial occlusion test on the arm. SUBJECT AND METHODS: Arterial occlusions were conducted at the arm of one individual for 10 min with 200 mmHg. Measurements were made twice a day on five different days. Both NIRS devices were fixed at the arm (covering the muscles extensor carpi ulnaris, extensor digitorum, and flexor carpi ulnaris). RESULTS: The experiment revealed that i) both devices could detect changes in muscle oxygenation and perfusion during the occlusion, but ii) the magnitudes and dynamic changes differed between the two devices. DISCUSSION AND CONCLUSION: Both devices had different performances with regard to the measurement of tissue oxygenation and perfusion. This study shows that it might be worthwhile to compare all NIRS tissue oximeters currently available for muscle measurement in a large systematic study to increase the comparability of measurements obtained with different devices.


Asunto(s)
Oximetría , Oxígeno , Adulto , Humanos , Italia , Masculino , Músculo Esquelético/metabolismo , Oximetría/instrumentación , Oximetría/normas , Oxígeno/metabolismo , Consumo de Oxígeno , Espectroscopía Infrarroja Corta
15.
Adv Exp Med Biol ; 1232: 291-297, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893423

RESUMEN

We present an IoT-based monitoring system for healthcare that allows for long-term measurements of blood pressure (BP), heart rate (HR), and body weight (BW), as well as near-infrared spectroscopy (NIRS) for measurement of prefrontal cortex (PFC) activity. To verify the applicability of the system, it was set up in a local fitness gym for a preliminary study. A total of 39 subjects, selected from members of the gym, participated in the study. We analyzed the BP, HR, and BW data, collected from the subjects over one half-year. In addition, to assess the degree of mental stress of the subjects, we analysed left-right asymmetry of the PFC activity using the laterality index at rest (LIR) of the NIRS parameter. Results show that the subjects were able to measure their physiological data by themselves when they visited the gym, after being instructed how to perform the measurements. Furthermore, the results also indicate that ordinary people can continuously monitor physiological functions such as brain function in a non-medical facility, such as a fitness gym.


Asunto(s)
Monitoreo Fisiológico , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Anciano , Femenino , Lateralidad Funcional , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Monitoreo Fisiológico/normas , Autoexamen/normas , Estrés Psicológico
16.
Adv Exp Med Biol ; 1232: 323-329, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893427

RESUMEN

Recent guidelines on cardiopulmonary resuscitation (CPR) have stressed the necessity to improve the quality of CPR. Our previous studies demonstrated the usefulness of monitoring cerebral blood oxygenation (CBO) during CPR by near-infrared spectroscopy (NIRS). The present study evaluates whether the NIRO-CCR1, a new NIRS device, is as useful in the clinical setting as the NIRO-200NX. We monitored CBO in 20 patients with cardiac arrest by NIRS. On the arrival of patients at the emergency department, the attending physician immediately assessed whether the patient was eligible for this study after conventional advanced life support and, if eligible, measured CBO in the frontal lobe by NIRS. We found that in all patients, the cerebral blood flow waveform was in synchrony with the chest compressions. Moreover, the tissue oxygenation index increased following cardiopulmonary bypass (CPB) in patients undergoing CPB, including one patient in whom CBO was monitored using the NIRO-CCR1. In addition, although the NIRO-CCR1 could display the pulse rate (Tempo) in real time, Tempo was not always detected, despite detection of the cerebral blood flow waveform. This suggested that chest compressions may not have been effective, indicating that the NIRO-CCR1 also seems useful to assess the quality of CPR. This study suggests that the NIRO-CCR1 can measure CBO during CPR in patients with cardiac arrest as effectively as the NIRO-200NX; in addition, the new NIRO-CCR1 may be even more useful, especially in prehospital fields (e.g. in an ambulance), since it is easy to carry.


Asunto(s)
Reanimación Cardiopulmonar , Circulación Cerebrovascular , Paro Cardíaco , Monitoreo Fisiológico , Oximetría , Espectroscopía Infrarroja Corta , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/normas , Oximetría/instrumentación , Oximetría/normas , Proyectos Piloto , Espectroscopía Infrarroja Corta/instrumentación , Espectroscopía Infrarroja Corta/normas
17.
Adv Exp Med Biol ; 1232: 331-337, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893428

RESUMEN

Obesity, a risk factor of coronary artery disease, is known to cause peripheral microcirculatory disturbances. This study evaluated the relationship between the degree of obesity and peripheral microcirculatory disturbances, using peripheral near infrared spectroscopy (NIRS) with a vascular occlusion test (VOT). We compared correlations between the NIRS parameter changes induced by VOT and body mass index (BMI) in patients with and without statin therapy. A NIRS probe was set on the right thenar eminence, brachial artery blood flow was blocked for 3 min, and then released. Although total hemoglobin (ΔcHb), deoxyhemoglobin (ΔHHb) and tissue oxygenation index (ΔTOI) were not correlated with BMI, a significant negative correlation was found between oxyhemoglobin (ΔO2Hb) and BMI in the overall study population (r = -0.255, p-value 0.02). In addition, a significant negative correlation was found between ΔO2Hb and BMI in patients without statin therapy (r = -0.353, p-value 0.02) but not in patients with statin therapy (r = -0.181, p-value 0.27). These findings suggest that ΔO2Hb may be a useful indicator to assess peripheral microcirculation.


Asunto(s)
Índice de Masa Corporal , Enfermedad de la Arteria Coronaria , Espectroscopía Infrarroja Corta , Anciano , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Masculino , Microcirculación/fisiología , Oxígeno , Consumo de Oxígeno , Oxihemoglobinas/metabolismo , Factores de Riesgo , Espectroscopía Infrarroja Corta/normas
18.
Adv Exp Med Biol ; 1232: 339-345, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893429

RESUMEN

We used a miniature broadband NIRS system to monitor concentration changes in brain oxygenation (oxy- and deoxy- haemoglobin [HbO2], [HHb]) and oxidised cytochrome-c-oxidase ([oxCCO]) during a high +Gz acceleration, induced by a human centrifuge, on two healthy experienced volunteers (2 male, 34 and 37 years). We performed a sequence of several +Gz exposures that were terminated at the onset of visual symptoms (loss of peripheral vision). Systemic parameters were recorded (i.e. heart rate, blood pressure and arterial saturation), and brain tissue blood volume changes ([HbT] = [HbO2] + [HHb]) and oxygen delivery ([HbDiff] = [HbO2] - [HHb]) were calculated. Volunteer 1 demonstrated a decrease in [HbT] of -3.49 ± 0.02 µMol and [HbDiff] of -3.23 ± 0.44 µMol, and an increase of [oxCCO] of 0.42 ± 0.01µMol. Volunteer 2 demonstrated a decrease in [HbDiff] of -4.37 ± 0.23 µMol, and no significant change in [HbT] (0.53 ± 0.06 µMol) and [oxCCO] (0.09 ± 0.06 µMol). The variability of the brain metabolic response was related to the level of ischaemia, suggesting that suppression of metabolism was due to lack of glucose substrate delivery rather than oxygen availability.


Asunto(s)
Aceleración , Complejo IV de Transporte de Electrones , Hemodinámica , Espectroscopía Infrarroja Corta , Adulto , Encéfalo/enzimología , Encéfalo/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Voluntarios Sanos , Humanos , Masculino , Estrés Oxidativo , Oximetría/instrumentación , Oxígeno/metabolismo
19.
Adv Exp Med Biol ; 1232: 355-360, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893431

RESUMEN

Epicardial adipose tissue (EAT) is associated with visceral fat and various cardiac disorders, such as atrial fibrillation and adverse cardiovascular events. Therefore, it is important to develop a simple and non-invasive inspection method to assess EAT, to prevent unfavorable cardiac events. This study assessed correlations between near-infrared spectroscopy (NIRS) changes induced by a vascular occlusion test (VOT) and EAT volume measured by cardiac computed tomography (CCT) in patients with suspected coronary artery disease. We also assessed correlations between body mass index (BMI) and EAT volume in the same population. In addition, these correlations were compared in patients treated with statin therapy and in those without statin therapy. A NIRS probe was set on the right thenar eminence, and brachial artery blood flow was blocked for 3 min before being released. A negative correlation was found between oxyhemoglobin (ΔO2Hb) and EAT volume in the overall study population (r = -0.236, p = 0.03). Interestingly, although a strong correlation was observed in patients without statin therapy (r = -0.488, p < 0.001), this correlation was not observed in patients with statin therapy (r = 0.157, p = 0.34). These findings suggest that NIRS measurements with VOT may be a useful method to identify patients with high EAT volume and high cardiovascular risks.


Asunto(s)
Enfermedad de la Arteria Coronaria , Espectroscopía Infrarroja Corta , Tejido Adiposo/metabolismo , Anciano , Índice de Masa Corporal , Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria/diagnóstico , Femenino , Humanos , Masculino , Oxihemoglobinas/metabolismo , Factores de Riesgo
20.
Arch Dis Child Fetal Neonatal Ed ; 105(1): 76-86, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31154420

RESUMEN

CONTEXT: Near-infrared spectroscopy (NIRS) is a non-invasive bedside monitor of tissue oxygenation that may be a useful clinical tool in monitoring of gut oxygenation in newborn infants. OBJECTIVE: To systematically review literature to determine whether NIRS is a reliable tool to monitor gut oxygenation on neonatal units. DATA SOURCES: PubMed and Embase databases were searched using the terms 'neonate', 'preterm infants', 'NIRS' and 'gut oxygenation' (2001-2018). STUDY SELECTION: Studies were included if they met inclusion criteria (clinical trial, observational studies, neonatal population, articles in English and reviewing regional gut oxygen saturations) and exclusion criteria (not evaluating abdominal NIRS or regional oxygen saturations). DATA EXTRACTION: Two authors independently searched PubMed and Embase using the predefined terms, appraised study quality and extracted from 30 studies the study design and outcome data. LIMITATIONS: Potential for publication bias, majority of studies were prospective cohort studies and small sample sizes. RESULTS: Thirty studies were reviewed assessing the validity of abdominal NIRS and potential application in neonates. Studies reviewed assessed abdominal NIRS in different settings including normal neonates, bolus and continuous feeding, during feed intolerance, necrotising enterocolitis and transfusion with packed red cells. Several observational studies demonstrated how NIRS could be used in clinical practice. CONCLUSIONS: NIRS may prove to be a useful bedside tool on the neonatal unit, working alongside current clinical tools in the monitoring of newborn infants (preterm and term) and inform clinical management. We recommend further studies including randomised controlled trials looking at specific measurements and cut-offs for abdominal NIRS for use in further clinical practice.


Asunto(s)
Oxígeno/metabolismo , Espectroscopía Infrarroja Corta , Circulación Esplácnica , Transfusión Sanguínea , Conducto Arterioso Permeable/complicaciones , Enterocolitis Necrotizante/prevención & control , Humanos , Recién Nacido , Mucosa Intestinal/metabolismo , Sepsis/prevención & control
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