A method for photoplethysmography signal quality assessment fusing multi-class features with multi-scale series information / 生物医学工程学杂志

Photoplethysmography (PPG) is often affected by interference, which could lead to incorrect judgment of physiological information. Therefore, performing a quality assessment before extracting physiological information is crucial. This paper proposed a new PPG signal quality assessment by fusing multi-class features with multi-scale series information to address the problems of traditional machine learning methods with low accuracy and deep learning methods requiring a large number of samples for training. The multi-class features were extracted to reduce the dependence on the number of samples, and the multi-scale series information was extracted by a multi-scale convolutional neural network and bidirectional long short-term memory to improve the accuracy. The proposed method obtained the highest accuracy of 94.21%. It showed the best performance in all sensitivity, specificity, precision, and F1-score metrics, compared with 6 quality assessment methods on 14 700 samples from 7 experiments. This paper provides a new method for quality assessment in small samples of PPG signals and quality information mining, which is expected to be used for accurate extraction and monitoring of clinical and daily PPG physiological information.

Anesthesia Depth Monitoring Based on Anesthesia Monitor with the Help of Artificial Intelligence / 中国医疗器械杂志

OBJECTIVE@#To use the low-cost anesthesia monitor for realizing anesthesia depth monitoring, effectively assist anesthesiologists in diagnosis and reduce the cost of anesthesia operation.@*METHODS@#Propose a monitoring method of anesthesia depth based on artificial intelligence. The monitoring method is designed based on convolutional neural network (CNN) and long and short-term memory (LSTM) network. The input data of the model include electrocardiogram (ECG) and pulse wave photoplethysmography (PPG) recorded in the anesthesia monitor, as well as heart rate variability (HRV) calculated from ECG, The output of the model is in three states of anesthesia induction, anesthesia maintenance and anesthesia awakening.@*RESULTS@#The accuracy of anesthesia depth monitoring model under transfer learning is 94.1%, which is better than all comparison methods.@*CONCLUSIONS@#The accuracy of this study meets the needs of perioperative anesthesia depth monitoring and the study reduces the operation cost.

Development of Respiratory Signal Monitoring System Based on Photoplethysmography / 中国医疗器械杂志

Breathing is of great significance in the monitoring of patients with obstructive sleep apnea hypopnea syndrome, perioperative monitoring and intensive care. In this study, a respiratory monitoring and verification system based on optical capacitance product pulse wave (PPG) is designed, which can synchronously collect human PPG signals. Through algorithm processing, the characteristic parameters of PPG signal are calculated, and the respiratory signal and respiratory frequency can be extracted in real time. In order to verify the accuracy of extracting respiratory signal and respiratory rate by the algorithm, the system adds the nasal airflow respiratory signal acquisition module to synchronously collect the nasal airflow respiratory signal as the standard signal for comparison and verification. Finally, the root mean square error between the respiratory rate extracted by the algorithm from the pulse wave and the standard respiratory rate is only 1.05 times/min.

Heart rate extraction algorithm based on adaptive heart rate search model / 生物医学工程学杂志

Photoplethysmography (PPG) is a non-invasive technique to measure heart rate at a lower cost, and it has been recently widely used in smart wearable devices. However, as PPG is easily affected by noises under high-intensity movement, the measured heart rate in sports has low precision. To tackle the problem, this paper proposed a heart rate extraction algorithm based on self-adaptive heart rate separation model. The algorithm firstly preprocessed acceleration and PPG signals, from which cadence and heart rate history were extracted respectively. A self-adaptive model was made based on the connection between the extracted information and current heart rate, and to output possible domain of the heart rate accordingly. The algorithm proposed in this article removed the interference from strong noises by narrowing the domain of real heart rate. From experimental results on the PPG dataset used in 2015 IEEE Signal Processing Cup, the average absolute error on 12 training sets was 1.12 beat per minute (bpm) (Pearson correlation coefficient: 0.996; consistency error: -0.184 bpm). The average absolute error on 10 testing sets was 3.19 bpm (Pearson correlation coefficient: 0.990; consistency error: 1.327 bpm). From experimental results, the algorithm proposed in this paper can effectively extract heart rate information under noises and has the potential to be put in usage in smart wearable devices.

Development of Respiratory Signal Extraction System Based on Photoplethysmography / 中国医疗器械杂志

Oxygen saturation and respiratory signals are important physiological signals of human body, respiratory monitoring plays an important role in clinical and daily life. A system was established to extract respiratory signals from photoplethysmography in this study. Including the collection of pulse wave signal, the extraction of respiratory signal, and the calculation of respiratory rate and pulse rate transmitted from the slave computer to the host computer in real time.

Emotion Recognition Based on Multiple Physiological Signals / 中国医疗器械杂志

Emotion is a series of reactions triggered by a specific object or situation that affects a person's physiological state and can, therefore, be identified by physiological signals. This paper proposes an emotion recognition model. Extracted the features of physiological signals such as photoplethysmography, galvanic skin response, respiration amplitude, and skin temperature. The SVM-RFE-CBR(Recursive Feature Elimination-Correlation Bias Reduction-Support Vector Machine) algorithm was performed to select features and support vector machines for classification. Finally, the model was implemented on the DEAP dataset for an emotion recognition experiment. In the rating scale of valence, arousal, and dominance, the accuracy rates of 73.5%, 81.3%, and 76.1% were obtained respectively. The result shows that emotional recognition can be effectively performed by combining a variety of physiological signals.

La relación de la edad con los componentes espectrales de las realizaciones sin ruido de señales fotopletismográficas: resultados de un enfoque de identificación no lineal / Relationship of Age with Spectral Components of Noise-Free Realizations of Photoplethysmographic Signals: Outcomes of a Nonlinear Identification Approach

Background: Age-related changes in the vascular network have been widely documented, however, nonlinear identification has been poorly applied to the analysis of cardiovascular signals. Objective: To determine the impact of age on spectral components of Noise-free realizations (NFR) obtained from photoplethysmographic signals, summarized in the Kernel Complexity Regressive Index (KCRIndex). Methods: With 190 apparently healthy participants (9 to 89 years) from Orense, Spain, Photoplethysmographic signals were recorded during 5 minutes in supine position using Nellcor-395 pulse oximeter; signals were digitized at 1000 Hz, and furtherly submitted to nonlinear identification via a kernel nonlinear autoregressive estimator. KCRIndex is defined as the average of at least three negative slope values at the NFR log-log spectrum in the 9 to 25 Hz frequency region. Results: KCRIndex decreased with age in a linear fashion and did not differ between genders. The regression line obtained was KCRIndex=-0.025*age+6.868 (r=-0.751). Conclusions: KCRIndex, is strongly correlated with age, thus opening up new possibilities for cardiovascular exploration at primary health care settings and even on open field conditions(AU)

Antecedentes: los cambios relacionados con la edad en la red vascular se han documentado ampliamente, sin embargo, la identificación no lineal solo se ha aplicado de manera esporádica al análisis de las señales cardiovasculares. Objetivo: determinar los cambios con la edad en los componentes espectrales de las realizaciones sin ruido (NFR) obtenidas a partir de señales fotopletismográficas, resumidas en el índice regresivo de la complejidad por núcleos (KCRIndex). Métodos: Con 190 participantes aparentemente sanos (de 9 a 89 años) residentes en Orense, España, se registraron señales fotopletismográficas durante 5 minutos en posición supina usando un oxímetro de pulso Nellcor-395; las señales se digitalizaron a 1000 Hz, y se sometieron a identificación no lineal a través de un estimador autorregresivo no lineal por núcleos. El KCRIndex se define como el promedio de al menos tres valores de pendiente negativos en el espectro log-log de NFR en la región de frecuencia de 9 a 25 Hz. Resultados: KCRIndex disminuyó con la edad de forma lineal y no difirió entre géneros. La línea de regresión obtenida fue KCRIndex = -0.025 * edad + 6.868 (r = -0.751). Conclusiones: Este índice propuesto está fuertemente correlacionado con la edad, lo que abre nuevas posibilidades para la exploración cardiovascular en entornos de atención primaria de salud e incluso en condiciones de campo(AU)

Assessing Accuracy of Wrist-Worn Wearable Devices in Measurement of Paroxysmal Supraventricular Tachycardia Heart Rate

BACKGROUND AND OBJECTIVES: Wrist-worn wearable devices provide heart rate (HR) monitoring function via photoplethysmography technology. Recently, these devices have been used by patients to measure the HR when palpitation occurs, but few validation studies of these instruments have been conducted. We assessed the accuracy of these devices for measuring a HR. METHODS: This study enrolled 51 consecutive patients with a history of paroxysmal supraventricular tachyarrhythmia (SVT) or paroxysmal palpitations who were scheduled to undergo an electrophysiological study (EPS). Three devices were assessed: Apple Watch Series 2 (Apple), Samsung Galaxy Gear S3 (Galaxy), and Fitbit Charge 2 (Fitbit). Patients were randomly assigned to wear 2 different devices. The HR at baseline and induced SVT were measured during the EPS. After successful ablation of SVT, HR measurements was also done during atrial and ventricular pacing study. RESULTS: The mean patient age was 44.4±16.6 years and 27 patients were male (53%). The accuracy (within ±5 beats per minute [bpm] of an electrocardiogram [ECG] measurement) of the baseline HR measurements was 100%, 100%, and 94%, for Apple, Galaxy, and Fitbit, respectively. The HR during induced SVT ranged from 108 bpm to 228 bpm and the accuracy (within ±10 bpm of an ECG) was 100%, 90%, and 87% for the Apple, Galaxy, and Fitbit, respectively. During pacing study, accuracy of these devices was also acceptable but tended to decrease as the HR increased, and showed differences between the devices. CONCLUSIONS: Wrist-worn wearable devices accurately measure baseline and induced SVT HR. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0002282

Comparação do índice tornozelo-braquial com parâmetros de rigidez e resistência arterial periférica avaliados por fotopletismografia em idosos / Comparison of the ankle-brachial index with parameters of stiffness and peripheral arterial resistance assessed by photoplethysmography in elderly patients

O índice tornozelo-braquial (ITB) utiliza a razão entre a pressão arterial sistólica do tornozelo e do braço para diagnosticar de forma não invasiva a doença arterial periférica (DAP). A fotopletismografia (photoplethysmography, PPG) faz a medição e o registro das modificações de volume sanguíneo do corpo humano por meio de técnicas ópticas. Objetivos O objetivo deste estudo foi comparar o ITB com parâmetros de rigidez arterial e resistência periférica avaliados pela PPG em idosos e propor um modelo de predição para o ITB. Métodos Foi realizado um estudo transversal quantitativo. A amostra foi composta por idosos atendidos no ambulatório médico de especialidades da Universidade do Sul de Santa Catarina (UNISUL). Foram verificados: idade, sexo, índice de massa corporal (IMC), presença de comorbidades, tabagismo e atividade física. Para comparação das variáveis obtidas com a PPG com o ITB, foi realizada regressão linear bivariada e multivariada, considerando erro α = 0,05. Resultados Foram avaliados 93 idosos, sendo 63,4% mulheres. Em 98,9% dos casos, o ITB apresentou-se dentro da normalidade. Na comparação do ITB e variáveis derivadas da PPG em relação à idade, foram demonstradas associações significativas. Contudo, não foram observadas associações significativas entre ITB e PPG. O modelo multivariado indicou que apenas idade, sexo e tabagismo foram associados ao ITB. Conclusões Como conclusão, o ITB e a PPG demonstraram associação com o envelhecimento arterial, tendo em vista sua correlação com a idade; contudo, o ITB foi relacionado apenas com idade, sexo e tabagismo. Mais estudos são necessários para avaliar o potencial uso da PPG como rastreio de doenças vasculares em rotinas ambulatórias

The ankle-brachial index (ABI) uses the ratio between systolic blood pressures at the ankle and the arm to diagnose peripheral arterial disease (PAD) noninvasively. Photoplethysmography (PPG) measures and records changes to the blood volume in the human body using optical techniques. Objectives The objective of this study was to compare ABI with arterial stiffness and peripheral resistance parameters assessed using PPG in elderly patients and to propose a model for prediction of ABI. Methods A cross-sectional, quantitative study was conducted. The sample comprised elderly patients seen at a medical specialties clinic at the Universidade do Sul de Santa Catarina (UNISUL), Brazil. Age, sex, body mass index (BMI), comorbidities, smoking, and physical activity were recorded. The variables obtained using PPG and ABI were compared using bivariate and multivariate linear regression, with an α error of 0.05. Results A total of 93 elderly patients were assessed, 63.4% of whom were women. In 98.9% of cases, ABI was within normal limits. Comparison of ABI with variables acquired by PPG revealed significant associations with age. However, no significant associations were observed between ABI and PPG. The multivariate model indicated that only age, sex, and smoking were associated with ABI. Conclusions In conclusion, ABI and PPG exhibited associations with arterial aging, considering its correlation with age. However, ABI was only related to age, sex, and smoking. More studies are needed to evaluate the potential uses of PPG for screening for vascular diseases in ambulatory settings

Area Triangulation Method for Automatic Detection of Venous Emptying Maneuvers

Abstract Venous refilling time (VRT) can diagnose the presence of venous diseases in lower limbs. In order to calculate VRT it is necessary to determine the End of the Emptying Maneuvers (EEM). First Derivative Method (FDM) can be employed for automatic detection of the EEM, but its sensitivity to artifacts and noise can degrade its performance. In contrast, studies report that Area Triangulation Method (ATM) evinces effectiveness in biosignals point finding. This work compares the exactness of ATM and FDM for recognition of the EEM. The annotations made by 3 trained human observers on 37 photoplethysmography records were used as a reference. Bland-Altman graphics supported the analysis of agreement among human observers and methods, which was complemented with Analysis of variance and Multiple Comparisons statistical tests. Results showed that ATM is more accurate than FDM for automatic detection of the EEM, with statistically significant differences (p-value < 0.01).

Current progress of photoplethysmography and SPO 2 for health monitoring

A photoplethysmograph (PPG) is a simple medical device for monitoring blood fl ow and transportation of substances in the blood. It consists of a light source and a photodetector for measuring transmitted and refl ected light signals. Clinically, PPGs are used to monitor the pulse rate, oxygen saturation, blood pressure, and blood vessel stiff ness. Wearable unobtrusive PPG monitors are commercially available. Here, we review the principle issues and clinical applications of PPG for monitoring oxygen saturation.

Aumento en la efectividad de la identificación de cimas y pies en el pulso fotopletismográfico al reconstruirlo mediante filtrado adaptativo / Increase in the effectiveness of identifying peaks and feet of the photoplethysmographic pulse to be reconstructed it using adaptive filtering

Resumen: Objetivo: Mejorar la identificación de cimas y pies en el pulso fotopletismográfico (PPG, por sus siglas en inglés), deformado por efecto del ruido miocinético, mediante la implementación de un dedal modificado y filtrado adaptativo. Método: Se obtuvo el PPG en 10 voluntarios sanos empleando 2 sistemas de fotopletismografía colocados en el dedo índice de cada mano, y registrándolos simultáneamente durante 3 min. Durante el primer minuto de registro, ambas manos estuvieron en reposo, y durante los 2 min posteriores, solo la mano izquierda realizó movimientos cuasi-periódicos para añadir ruido miocinético. Se emplearon 2 metodologías para procesar las señales fuera de línea, en una se usó un filtro con el algoritmo de mínimos cuadrados promediados (LMS, por sus siglas en inglés) y en la otra se hizo un preprocesamiento adicional al filtrado LMS. Ambas metodologías fueron comparadas y la de menor error porcentual en la señal recuperada se utilizó para valorar la mejora en la identificación de cimas y pies del PPG. Resultados: El error promedio obtenido fue del 22.94% para la primera metodología, y del 3.72% para la segunda. Los errores en la identificación de cimas y pies antes de filtrar el PPG fueron del 24.26 y 48.39%, respectivamente, una vez filtrados, disminuyeron a 2.02 y 3.77%, respectivamente. Conclusiones: El filtrado adaptativo basado en el algoritmo LMS, más una etapa de preprocesamiento, permite atenuar el ruido miocinético en el PPG, y aumentar la efectividad en la identificación de cimas y pies de pulso, que resultan de gran importancia para una valoración médica.

Abstract: Objective: To improve the identification of peaks and feet in photoplethysmographic (PPG) pulses deformed by myokinetic noise, through the implementation of a modified fingertip and applying adaptive filtering. Method: PPG signals were recordedfrom 10 healthy volunteers using two photoplethysmography systems placed on the index finger of each hand. Recordings lasted three minutes andwere done as follows: during the first minute, both handswere at rest, and for the lasting two minutes only the left hand was allowed to make quasi-periodicmovementsin order to add myokinetic noise. Two methodologies were employed to process the signals off-line. One consisted on using an adaptive filter based onthe Least Mean Square (LMS) algorithm, and the other includeda preprocessing stage in addition to the same LMS filter. Both filtering methods were compared and the one with the lowest error was chosen to assess the improvement in the identification of peaks and feet from PPG pulses. Results: Average percentage errorsobtained wereof 22.94% with the first filtering methodology, and 3.72% withthe second one. On identifying peaks and feet from PPG pulsesbefore filtering, error percentages obtained were of 24.26% and 48.39%, respectively, and once filtered error percentageslowered to 2.02% for peaks and 3.77% for feet. Conclusions: The attenuation of myokinetic noise in PPG pulses through LMS filtering, plusa preprocessing stage, allows increasingthe effectiveness onthe identification of peaks and feet from PPG pulses, which are of great importance for medical assessment.

System for Collecting Biosignal Data from Multiple Patient Monitoring Systems / 대한의료정보학회지

OBJECTIVES: Biosignal data include important physiological information. For that reason, many devices and systems have been developed, but there has not been enough consideration of how to collect and integrate raw data from multiple systems. To overcome this limitation, we have developed a system for collecting and integrating biosignal data from two patient monitoring systems. METHODS: We developed an interface to extract biosignal data from Nihon Kohden and Philips monitoring systems. The Nihon Kohden system has a central server for the temporary storage of raw waveform data, which can be requested using the HL7 protocol. However, the Philips system used in our hospital cannot save raw waveform data. Therefore, our system was connected to monitoring devices using the RS232 protocol. After collection, the data were transformed and stored in a unified format. RESULTS: From September 2016 to August 2017, we collected approximately 117 patient-years of waveform data from 1,268 patients in 79 beds of five intensive care units. Because the two systems use the same data storage format, the application software could be run without compatibility issues. CONCLUSIONS: Our system collects biosignal data from different systems in a unified format. The data collected by the system can be used to develop algorithms or applications without the need to consider the source of the data.

New Aging Index Using Signal Features of Both Photoplethysmograms and Acceleration Plethysmograms / 대한의료정보학회지

OBJECTIVES: Acceleration plethysmograms (APGs) are obtained by taking the second derivative of photoplethysmograms (PPGs) and are noninvasive circulatory signals related to risk factors for atherosclerosis with age. There has been growing interest in the development of mobile devices to collect and analyze PPG single features for ambulatory health monitoring. The present study aimed to extract a new feature from the morphologies of APG and PPG signals to classify the dominant indices related to the pulsatile volume of blood in tissue according to age. METHODS: Ten APG and 14 PPG indices were simultaneously extracted. All indices were compared via Pearson correlation coefficients (r) and a regression analysis. We introduced a combined index extracted from both the PPG and APG indices defined as the inflection point area plus the d_peak (IPAD). The participants included 93 healthy adults aged 36–86 years with a mean ± standard deviation age of 57.43 ± 11.99 years. RESULTS: The d_peak and age index for the APG indices were significantly correlated with age (r = −0.408, p < 0.0001 and r = 0.296, p = 0.0039, respectively). Only the A1 time for PPG indices was moderately correlated with age (r = −0.247, p = 0.017). The stiffness index, including individual height information, was not related to age (r = −0.031, p = 0.7713). However, the combined IPAD index was significantly more correlated with age (r = 0.56, p < 0.001) than the other indices. CONCLUSIONS: The proposed index outperformed the other 24 indices for evaluating vascular aging. We suggest that the IPAD is a significant factor related to the clinical information embedded in the PPG waveform.

Accuracy of Heart Rate Measurement Using Smartphones During Treadmill Exercise in Male Patients With Ischemic Heart Disease

OBJECTIVE: To evaluate the accuracy of a smartphone application measuring heart rates (HRs), during an exercise and discussed clinical potential of the smartphone application for cardiac rehabilitation exercise programs. METHODS: Patients with heart disease (14 with myocardial infarction, 2 with angina pectoris) were recruited. Exercise protocol was comprised of a resting stage, Bruce stage II, Bruce stage III, and a recovery stage. To measure HR, subjects held smartphone in their hands and put the tip of their index finger on the built-in camera for 1 minute at each exercise stage such as resting stage, Bruce stage II, Bruce stage III, and recovery stage. The smartphones recorded photoplethysmography signal and HR was calculated every heart beat. HR data obtained from the smartphone during the exercise protocol was compared with the HR data obtained from a Holter electrocardiography monitor (control). RESULTS: In each exercise protocol stage (resting stage, Bruce stage II, Bruce stage III, and the recovery stage), the HR averages obtained from a Holter monitor were 76.40±12.73, 113.09±14.52, 115.64±15.15, and 81.53±13.08 bpm, respectively. The simultaneously measured HR averages obtained from a smartphone were 76.41±12.82, 112.38±15.06, 115.83±15.36, and 81.53±13 bpm, respectively. The intraclass correlation coefficient (95% confidence interval) was 1.00 (1.00–1.00), 0.99 (0.98–0.99), 0.94 (0.83–0.98), and 1.00 (0.99–1.00) in resting stage, Bruce stage II, Bruce stage III, and recovery stage, respectively. There was no statistically significant difference between the HRs measured by either device at each stage (p>0.05). CONCLUSION: The accuracy of measured HR from a smartphone was almost overlapped with the measurement from the Holter monitor in resting stage and recovery stage. However, we observed that the measurement error increased as the exercise intensity increased.

Design of a Front-end Device of Heart Rate Variability Analysis System Based on Photoplethysmography / 生物医学工程学杂志

Heart rate variability (HRV) is the difference between the successive changes in the heartbeat cycle, and it is produced in the autonomic nervous system modulation of the sinus node of the heart. The HRV is a valuable indicator in predicting the sudden cardiac death and arrhythmic events. Traditional analysis of HRV is based on a multielectrocardiogram (ECG), but the ECG signal acquisition is complex, so we have designed an HRV analysis system based on photoplethysmography (PPG). PPG signal is collected by a microcontroller from human's finger, and it is sent to the terminal via USB-Serial module. The terminal software not only collects the data and plot waveforms, but also stores the data for future HRV analysis. The system is small in size, low in power consumption, and easy for operation. It is suitable for daily care no matter whether it is used at home or in a hospital.

Research on PPG Signal Reconstruction Based on Compressed Sensing / 中国医疗器械杂志

In order to improve the storage and transmission efficiency of dynamic photoplethysmography (PPG) signals in the detection process and reduce the redundancy of signals, the modified adaptive matching pursuit (MAMP) algorithm was proposed according to the sparsity of the PPG signal. The proposed algorithm which is based on reconstruction method of sparse adaptive matching pursuit (SAMP), could improve the accuracy of the sparsity estimation of signals by using both variable step size and the double threshold conditions. After experiments on the simulated and the actual PPG signals, the results show that the modified algorithm could estimate the sparsity of signals accurately and quickly, and had good anti-noise performance. Contrasting with SAMP and orthogonal matching pursuit (OMP), the reconstruction speed of the algorithm was faster and the accuracy was high.

Alteraciones de la microcirculación en pacientes con anemia drepanocítica según técnicas fotopletismográficas / Changes of microcirculation in patients with sickle-cell anemia according to photoplethysmographical techniques

Se realizó un estudio observacional, descriptivo y transversal, de serie de casos, de 74 individuos (24 con anemia drepanocítica y 50 aparentemente sanos portadores de hemoglobinopatía SS), quienes asistieron a la Consulta de Hematología Especial del Hospital General Docente "Dr. Juan Bruno Zayas Alfonso" de Santiago de Cuba, durante el periodo 2013-2014, con vistas a identificar las alteraciones de la microcirculación según variabilidad de los parámetros fotopletismográficos. Se realizaron estudios con el Angiodin PD 3000, a partir del registro basal de la onda de volumen de pulso y el test de hiperemia reactiva. La fotopletismografía en estado basal de miembros inferiores mostró que los pacientes con anemia drepanocítica presentaron alteraciones en el sistema circulatorio, en tanto, las macroangiopatías tuvieron mayor frecuencia en la hiperemia reactiva. Los resultados obtenidos revelaron la utilidad de estas pruebas en la detección de trastornos funcionales circulatorios.

An observational, descriptive and cross-sectional cases series study, of 74 individuals (24 with sickel-cell anemia and 50 apparently healthy with hemoglobinopathies SS) who attended the Special Hematology Department from "Dr. Juan Bruno Zayas Alfonso" Teaching General Hospital in Santiago de Cuba was carried out during the period 2013-2014, with the aim of identifying the changes of the microcirculation according to variability of the photopletismographical parameters. Studies with the Angiodin PD 3000 were carried out, from the basal register of the pulse volume wave and the reactive hyperemia test. The photoplethysmography in basal state of lower members showed that patients with sickle-cell anemia presented changes in the circulatory system, while, the macroangiopathies had higher frequency in the reactive hyperemia. The obtained results revealed the usefulness of these tests in the detection of circulatory functional disorders.

Evaluation of quality of life and photoplethysmography in patients with chronic venous insufficiency treated with foam sclerotherapy

BACKGROUND: Ultrasound-guided foam sclerotherapy plays a major role in treatment of chronic venous insufficiency, providing clinical and hemodynamic improvement to patients undergoing treatment.OBJECTIVES: To examine the relationships between venous refilling time and impact of venous disease on quality of life and between changes in venous refilling time and improvement of symptoms after ultrasound-guided foam sclerotherapy for chronic venous insufficiency. METHODS: Thirty-two patients classified as C4, C5 or C6 answered a questionnaire on quality of life and symptoms and their venous filling time was measured using photoplethysmography before and 45 days after treatment of chronic venous insufficiency with ultrasound-guided foam sclerotherapy.RESULTS: Statistically significant improvements were observed in quality of life scores and in venous filling time and in the following symptoms: aching, heavy legs, restless legs, swelling, burning sensations, and throbbing (p<0.0001). A similar improvement was also seen in the work and social domains of quality of life (p<0.0001).CONCLUSIONS: As confirmed by questionnaire scores and venous refilling times, ultrasound-guided foam sclerotherapy demonstrated efficacy and resulted in high satisfaction levels and low rates of major complications.

CONTEXTO: A escleroterapia com espuma guiada por ultrassom (EGUS) ocupa lugar de destaque no tratamento da insuficiência venosa crônica (IVC), proporcionando melhora clínica e hemodinâmica aos pacientes submetidos ao tratamento.OBJETIVOS: Verificar a correlação entre dados obtidos por questionário de qualidade de vida e de sintomas com dados obtidos por fotopletismografia (FPG), antes e depois do tratamento por escleroterapia com espuma guiada por ultrassom (EGUS) da insuficiência venosa crônica (IVC). MÉTODOS: Um grupo de 32 pacientes, classificados como C4, C5 e C6, foi submetido à aplicação de questionário de qualidade de vida e sintomas, sendo aferido o tempo de enchimento venoso (TEV) por FPG antes e 45 dias depois do tratamento da IVC através de EGUS. O teste do sinal foi utilizado para análise estatística da melhora dos escores dos questionários e do TEV. O teste de McNemar foi utilizado para avaliação da melhora nos sintomas e do impacto do tratamento nas atividades laborais e sociais dos pacientes.RESULTADOS: Houve melhora nos escores dos questionários de qualidade de vida e no TEV, com significância estatística (p<0,0001). Houve melhora estatisticamente significativa nos sintomas: dor, cansaço, edema, queimação, pernas inquietas e latejamento (p<0,0001). Incremento na qualidade laboral e social após o tratamento apresentou melhora estatisticamente significativa (p<0,0001). Não ocorreram complicações maiores ou efeitos adversos nesta série.CONCLUSÕES: A EGUS mostrou-se eficaz, com alto índice de satisfação e baixas taxas de complicacões maiores, ratificada pelos escores dos questionários e pelos TEVs aferidos pela FPG.

Analysis of Pulse Rate Variability and Its Application to Wearable Smart Devices / 中国医疗器械杂志

In this paper, a reflection type photoelectric pulse wave sensor was designed for short-term pulse rate variability analysis. Photoplethysmography (PPG) signals and ECG signals (obtained with the Dimetek MicroECG recorder Dicare-m1CP) were recorded synchronously from 20 healthy subjects. The analytical results show a significant correlation (correlation coefficient r > 0.99) between the PPG-derived peak-to-peak (PP) intervals and the ECG-derived RR intervals. Besides, there are no significant differences (P > 0.05) between the HRV measured by ECG and the PRV quantified by the PPG whether in time domain, frequency domain, or the Poincaré plot parameters. The experimental results suggest that the PPG-based short-term PRV analysis can be consistent with the ECG-based HRV measurement in wearable smart devices.