1.A review of deep learning methods for non-contact heart rate measurement based on facial videos.
Shuyue GUAN ; Yimou LYU ; Yongchun LI ; Chengzhi XIA ; Lin QI ; Lisheng XU
Journal of Biomedical Engineering 2025;42(1):197-204
Heart rate is a crucial indicator of human health with significant physiological importance. Traditional contact methods for measuring heart rate, such as electrocardiograph or wristbands, may not always meet the need for convenient health monitoring. Remote photoplethysmography (rPPG) provides a non-contact method for measuring heart rate and other physiological indicators by analyzing blood volume pulse signals. This approach is non-invasive, does not require direct contact, and allows for long-term healthcare monitoring. Deep learning has emerged as a powerful tool for processing complex image and video data, and has been increasingly employed to extract heart rate signals remotely. This article reviewed the latest research advancements in rPPG-based heart rate measurement using deep learning, summarized available public datasets, and explored future research directions and potential advancements in non-contact heart rate measurement.
Humans
;
Deep Learning
;
Heart Rate/physiology*
;
Photoplethysmography/methods*
;
Video Recording
;
Face
;
Monitoring, Physiologic/methods*
;
Signal Processing, Computer-Assisted
2.A signal sensing system for monitoring the movement of human respiratory muscle based on the thin-film varistor.
Yueyang YUAN ; Zhongping ZHANG ; Lixin XIE ; Haoxuan HUANG ; Wei LIU
Journal of Biomedical Engineering 2025;42(4):733-738
In order to accurately capture the respiratory muscle movement and extract the synchronization signals corresponding to the breathing phases, a comprehensive signal sensing system for sensing the movement of the respiratory muscle was developed with applying the thin-film varistor FSR402 IMS-C07A in this paper. The system integrated a sensor, a signal processing circuit, and an application program to collect, amplify and denoise electronic signals. Based on the respiratory muscle movement sensor and a STM32F107 development board, an experimental platform was designed to conduct experiments. The respiratory muscle movement data and respiratory airflow data were collected from 3 healthy adults for comparative analysis. In this paper, the results demonstrated that the method for determining respiratory phase based on the sensing the respiratory muscle movement exhibited strong real-time performance. Compared to traditional airflow-based respiratory phase detection, the proposed method showed a lead times ranging from 33 to 210 ms [(88.3 ± 47.9) ms] for expiration switched into inspiration and 17 to 222 ms [(92.9 ± 63.8) ms] for inspiration switched into expiration, respectively. When this system is applied to trigger the output of the ventilator, it will effectively improve the patient-ventilator synchrony and facilitate the ventilation treatment for patients with respiratory diseases.
Humans
;
Respiratory Muscles/physiology*
;
Signal Processing, Computer-Assisted
;
Movement/physiology*
;
Respiration
;
Monitoring, Physiologic/methods*
;
Adult
3.Research progress on the early warning of heart failure based on remote dynamic monitoring technology.
Ying SHI ; Mengwei LI ; Lixuan LI ; Wei YAN ; Desen CAO ; Zhengbo ZHANG ; Muyang YAN
Journal of Biomedical Engineering 2025;42(4):857-862
Heart failure (HF) is the end-stage of all cardiac diseases, characterized by high prevalence, high mortality, and heavy social and economic burden. Early warning of HF exacerbation is of great value for outpatient management and reducing readmission rates. Currently, remote dynamic monitoring technology, which captures changes in hemodynamic and physiological parameters of HF patients, has become the primary method for early warning and is a hot research topic in clinical studies. This paper systematically reviews the progress in this field, which was categorized into invasive monitoring based on implanted devices, non-invasive monitoring based on wearable devices, and other monitoring technologies based on audio and video. Invasive monitoring primarily involves direct hemodynamic parameters such as left atrial pressure and pulmonary artery pressure, while non-invasive monitoring covers parameters such as thoracic impedance, electrocardiogram, respiration, and activity levels. These parameters exhibit characteristic changes in the early stages of HF exacerbation. Given the clinical heterogeneity of HF patients, multi-source information fusion analysis can significantly improve the prediction accuracy of early warning models. The results of this study suggest that, compared with invasive monitoring, non-invasive monitoring technology, with its advantages of good patient compliance, ease of operation, and cost-effectiveness, combined with AI-driven multimodal data analysis methods, shows significant clinical application potential in establishing an outpatient management system for HF.
Humans
;
Heart Failure/physiopathology*
;
Monitoring, Physiologic/methods*
;
Wearable Electronic Devices
;
Remote Sensing Technology
;
Early Diagnosis
;
Electrocardiography
;
Hemodynamics
4.Relevance of intra-abdominal pressure monitoring in non-operative management of patients with blunt liver and splenic injuries.
Vivek KUMAR ; Ramesh VAIDYANATHAN ; Dinesh BAGARIA ; Pratyusha PRIYADARSHINI ; Abhinav KUMAR ; Narendra CHOUDHARY ; Sushma SAGAR ; Amit GUPTA ; Biplab MISHRA ; Mohit JOSHI ; Kapil Dev SONI ; Richa AGGARWAL ; Subodh KUMAR
Chinese Journal of Traumatology 2025;28(4):307-312
PURPOSE:
Non-operative management (NOM) has been validated for blunt liver and splenic injuries. Literature on continuous intra-abdominal pressure (IAP) monitoring as a part of NOM remains to be equivocal. The study aimed to find any correlation between clinical parameters and IAP, and their effect on the NOM of patients with blunt liver and splenic injury.
METHOD:
A prospective cross-sectional study conducted at a level I trauma center from October 2018 to January 2020 including 174 patients who underwent NOM following blunt liver and splenic injuries. Hemodynamically unstable patients or those on ventilators were excluded, as well as patients who suffered significant head, spinal cord, and/or bladder injuries. The study predominantly included males (83.9%) with a mean age of 32.5 years. IAP was monitored continuously and the relation of IAP with various parameters, interventions, and outcomes were measured. Data were summarized as frequency (percentage) or mean ± SD or median (Q1, Q3) as indicated. χ2 or Fisher's exact test was used for categorical variables, while for continuous variables parametric (independent t-test) or nonparametric tests (Wilcoxon rank sum test) were used as appropriate. Clinical and laboratory correlates of IAP < 12 with p < 0.200 in the univariable logistic regression analysis were included in the multivariable analysis. A p < 0.05 was used to indicate statistical significance.
RESULTS:
Intra-abdominal hypertension (IAH) was seen in 19.0% of the study population. IAH was strongly associated with a high injury severity score (p < 0.001), and other physiological parameters like respiratory rate (p < 0.001), change in abdominal girth (AG) (p < 0.001), and serum creatinine (p < 0.001). IAH along with the number of solid organs involved, respiratory rate, change in AG, and serum creatinine was associated with the intervention, either operative or non-operative (p = 0.001, p = 0.002, p < 0.001, p < 0.001, p = 0.013, respectively). On multivariable analysis, IAP (p = 0.006) and the mean change of AG (p = 0.004) were significantly associated with the need for intervention.
CONCLUSION
As a part of NOM, IAP should be monitored as a continuous vital. However, the decision for any intervention, either operative or non-operative cannot be guided by IAP values alone.
Humans
;
Male
;
Adult
;
Female
;
Wounds, Nonpenetrating/physiopathology*
;
Spleen/injuries*
;
Prospective Studies
;
Cross-Sectional Studies
;
Liver/injuries*
;
Middle Aged
;
Monitoring, Physiologic/methods*
;
Pressure
;
Abdominal Injuries/physiopathology*
;
Intra-Abdominal Hypertension
;
Young Adult
5.Perioperative digital surveillance with a multiparameter vital signs monitoring system in a gastric cancer patient with diabetes.
Reziya AIERKEN ; Z W JIANG ; G W GONG ; P LI ; X Y LIU ; F JI
Chinese Journal of Gastrointestinal Surgery 2025;28(11):1318-1322
Objective: To evaluate the application value of a digital technology-based multiparameter vital signs monitoring system in perioperative comprehensive full-cycle surveillance. Methods: A comprehensive multidimensional vital signs monitoring system was developed through the integration of medical-grade wireless wearable devices, incorporating patch-type ambulatory electrocardiographic monitor, continuous glucose monitoring sensor, pulse oximeter, wireless digital thermometer, smart wristband, and bioelectrical impedance analyzer. This system facilitates continuous real-time acquisition of multiple physiological parameters including electrocardiogram, blood glucose, oxygen saturation, body temperature, physical activity, and body composition indices. The acquired data were systematically integrated and analyzed through a four-level digital architecture consisting of nurse mobile interfaces, bedside patient terminals, centralized ward monitoring displays, and hospital management information systems. One patient with gastric cancer complicated by diabetes mellitus was selected for full-cycle digital monitoring from preoperative evaluation to hospital discharge. The technical performance of the monitoring system was assessed in terms of data acquisition continuity and timeliness of abnormal event alerts. Results: The monitoring system effectively identified early postoperative abnormalities, such as decreased oxygen saturation and blood glucose fluctuations, providing timely guidance for clinical intervention. The built-in algorithm enabled visualization of perioperative stress levels through heart rate variability indices and continuous glucose monitoring data. The patient demonstrated good compliance with early postoperative mobilization, and the satisfaction score for monitoring management was 4 points based on the Likert 5-point scale. Conclusions: The multiparameter vital signs monitoring system enhanced the precision of perioperative management through continuous and dynamic physiological status assessment. Its modular design aligns with the principles of enhanced recovery after surgery, offering a novel technological solution for intelligent perioperative management.
Humans
;
Stomach Neoplasms/physiopathology*
;
Vital Signs
;
Monitoring, Physiologic/instrumentation*
;
Diabetes Mellitus
;
Wearable Electronic Devices
;
Perioperative Period
6.Intelligent Monitoring System Based on Computer Vision and Artificial Intelligence.
Chinese Journal of Medical Instrumentation 2025;49(1):74-79
To ensure the quality of care for inpatients in ophthalmic hospitals, address the complex and variable conditions of postoperative patients, and conduct more comprehensive, accurate and real-time monitoring of patients, an intelligent monitoring system based on computer vision and artificial intelligence has been designed. This system is employed for real-time monitoring of patient health conditions and intelligent care, with primary applications in medical monitoring, rehabilitation therapy, and inpatient care. It comprises intelligent data acquisition devices, smart cameras, continuous physiological data analysis algorithms, AI algorithms, and software. Given the complex and variable conditions of postoperative patients in ophthalmic hospitals, a comprehensive, accurate, and real-time monitoring of patients is required. Therefore, it is necessary to explore a monitoring technology that imposes low physiological and psychological burdens. The intelligent monitoring system can continuously collect patients' physiological parameter indicators and transmit the monitoring data to doctors' workstations or nurse stations after analysis using intelligent algorithms, providing new tools for patient monitoring, disease assessment, risk warning, and more. Furthermore, through the application of computer vision and artificial intelligence technologies, the system can analyze facial expressions, body postures, and other data to identify patients' emotional states and bedridden postures, enabling the timely detection of abnormal situations and implementation corresponding measures. This helps improving the daily work of medical staff, enhance the nursing safety in single-patient rooms in wards, and potentially find applications in the care of critically ill patients and elderly patients, thereby improving nursing efficiency and quality.
Artificial Intelligence
;
Humans
;
Monitoring, Physiologic/methods*
;
Algorithms
7.Design and Implementation of Non-Invasive Hemodynamic Monitoring System Based on Impedance Cardiogram Method.
Fuhao KANG ; Qi YIN ; Yanan LIU ; Lin HUANG ; Yan HANG ; Jilun YE ; Xu ZHANG
Chinese Journal of Medical Instrumentation 2025;49(1):80-88
Hemodynamic monitoring can reflect cardiac function and blood perfusion and is an indispensable monitoring method in clinical practice. Invasive hemodynamic monitoring methods represented by the thermodilution method are limited in their clinical application scope because they require vascular cannulation. Non-invasive hemodynamic monitoring has attracted extensive attention from medical companies and clinicians at home and abroad in recent years due to its advantages such as safety, non-invasiveness, continuous monitoring, simple operation, and low cost. This paper designs a non-invasive hemodynamic monitoring system based on the impedance cardiography, including hardware, algorithm, software design, and performance parameter evaluation. Among them, the hardware part mainly includes a differential high-frequency constant current source stimulation circuit, impedance cardiogram signal acquisition, and ECG signal acquisition circuit. Signal processing includes wave filtering, impedance cardiogram signal calibration, and ECG signal and impedance cardiogram signal feature point recognition. According to the collected impedance cardiogram and ECG signals, hemodynamic parameters such as heart rate (HR), stroke volume (SV), cardiac output (CO), stroke index (SI), cardiac index (CI), and cardiac contractility index (ICON) are calculated based on the Nyboer thoracic cylinder model. After testing, the key technical indicators of the system hardware are better than that of the relevant medical device standards. The system was used to collect impedance cardiogram and ECG signal data from 40 volunteers. The calculated HR, SV, and CO, three important hemodynamic indicators, were compared with the ICONCore non-invasive cardiac output monitor of OSYPKA Medical in Germany. Their Pearson correlation coefficients were 0.992 ( P<0.001), 0.948 ( P<0.001), and 0.933 ( P<0.001), respectively, verifying that the designed system has high accuracy and reliability.
Cardiography, Impedance/methods*
;
Humans
;
Hemodynamic Monitoring/methods*
;
Equipment Design
;
Signal Processing, Computer-Assisted
;
Hemodynamics
;
Algorithms
;
Monitoring, Physiologic/methods*
;
Electrocardiography
8.Development of a Microstream End-Tidal Carbon Dioxide Monitoring System with Integrated Gas Circuit.
Yanan LIU ; Xuedong SONG ; Qi YIN ; Fuhao KANG ; Yan HANG ; Jilun YE ; Xu ZHANG
Chinese Journal of Medical Instrumentation 2025;49(2):204-211
End-tidal carbon dioxide monitoring is an important means of evaluating human lung function and is widely used in fields such as clinical emergency treatment and cardiopulmonary resuscitation. This paper develops a microstream end-tidal carbon dioxide monitoring system. It adopts an integrated gas circuit design to further reduce the size of the equipment. The system uses the method of calculating the root mean square (RMS) of differential pressure signals to regulate the gas circuit flow, enabling the system to stably operate at a flow state of 30 mL/min. In addition, by simultaneously detecting multiple environmental parameters such as temperature and pressure, the system realizes system state monitoring and gas parameter compensation. The test results show that various indicators of the system meet the requirements of relevant standards, laying a good foundation for subsequent engineering applications.
Carbon Dioxide/analysis*
;
Equipment Design
;
Monitoring, Physiologic/methods*
;
Humans
9.Development of a Homecare Atherosclerosis Monitoring System Integrated with Cardio-Ankle Vascular Index.
Xichun XU ; Kexin CHEN ; Jinqi LIN ; Guo DAN ; Xu ZHANG ; Jilun YE ; Xin HU
Chinese Journal of Medical Instrumentation 2025;49(5):545-552
Cardiovascular disease (CVD) is the leading cause of death worldwide. As the key pathological basis of CVD, arteriosclerosis holds great significance for early screening. However, existing clinical and homecare detection devices have many shortcomings; for instance, the commonly used non-invasive indicator PWV (pulse wave velocity) is easily interfered by blood pressure.This study developed a homecare arteriosclerosis monitoring system, which integrates the measurement functions of cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI). The hardware design of the system includes an integrated structure of flexible silver ion electrodes and clip-type cuffs, a contact heart sound sensor, and a stepped deflation blood pressure measurement module. Meanwhile, a high-precision analog-to-digital conversion module and the STM32F405 main control chip are used to realize the synchronous acquisition of multiple signals.In terms of software, the underlying driver program was designed through MDK (Keil5), and a user interface was built on the Visual Studio platform to achieve functions such as data acquisition, display, and storage. At the algorithm level, the system adopted algorithms like the Pan-Tompkins algorithm to identify key feature points of physiological signals, and then calculate CAVI and ABI.System test results show that the ECG input noise of the system is less than 20 μV, the common-mode rejection ratio is 95 dB, and the blood pressure measurement error does not exceed 2 mmHg, which meets the design goals. Clinical data analysis indicates that CAVI is highly positively correlated with pulse wave velocity (PWV) ( r=0.85, P<0.001), but CAVI is less affected by blood pressure fluctuations. In addition, with the increase of risk factors (such as hypertension, hyperlipidemia, coronary heart disease, etc.) and age, arteriosclerosis indicators (CAVI, PWV, ABI) all show an upward trend.In conclusion, the homecare arteriosclerosis monitoring system proposed in this study not only overcomes the problems of traditional devices that rely on professional operation and are susceptible to blood pressure interference, but also provides a reliable tool for arteriosclerosis screening in home scenarios, and has important reference value for clinical diagnosis.
Humans
;
Cardio Ankle Vascular Index
;
Home Care Services
;
Atherosclerosis/diagnosis*
;
Ankle Brachial Index
;
Algorithms
;
Pulse Wave Analysis
;
Arteriosclerosis/diagnosis*
;
Monitoring, Physiologic/instrumentation*
10.Accuracy of the daily dengue severity score in assessing disease severity in children
Mary Ann G. Abella ; Belle M. Ranile
Pediatric Infectious Disease Society of the Philippines Journal 2024;25(2):69-79
BACKGROUND
Dengue is a global health concern, particularly in tropical regions such as the Philippines. In 2019,Cebu City reported the highest number of dengue cases in Central Visayas with 3,290 cases and 20 deaths, an 11.8% increase compared to 20181 . To help predict disease outcomes and provide timely management, a scoring system, the Daily Dengue Severity Score (DDSS)² was utilized.
OBJECTIVETo determine the clinicodemographic profile of dengue patients, determine the accuracy of the DDSS in assessing disease severity, and determine a cut off score that suggests severe dengue.
METHODSPatients 1 month to 18 years admitted for dengue at Perpetual Succour Hospital from January 2018 to December 2020 were included. Cases were classified as Dengue without Warning Signs, Dengue with Warning Signs, and Severe Dengue, and scored using the DDSS. Statistical analysis used were Geometric mean and Area Under the Receiver Operating Characteristic (AUROC) curves to analyze the discriminative performance of the DDSS among the different disease severity states.
RESULTSOut of 327 cases, 34 were classified as Dengue without Warning Signs, 271 Dengue with Warning Signs, and 22 Severe Dengue. The highest mean DDSS was 17.7 ±14.0 at Day -4 among those with Severe Dengue, and the lowest mean DDSS was 1.1 ± 2.0 at Day +3 among those with Dengue without Warning Signs. A cut off point of 10 on Day -1 predicted subsequent Severe Dengue among patients with Dengue with Warning Signs. In 91.39% of cases, there was a significant relationship between the DDSS and dengue classification, and the higher the DDSS, the more severe the disease.
CONCLUSIONMajority of dengue patients were males, aged 8.1 to 9.2 years. DDSS showed 66.67% sensitivity, 92.86% specificity, a positive likelihood ratio of 9.3, and a cutoff of 10 is predictive of severe dengue among patients with dengue with warning signs.
Human ; Dengue ; Scoring Methods ; Research Design ; Patient Monitoring ; Monitoring, Physiologic


Result Analysis
Print
Save
E-mail