Monitoring vital signs and locations of certain classes of ambulatory patients can be useful in overcrowded emergency departments and at disaster sce

Miners working at high altitude must handle extreme climatic and physiological hazards without specialized medical supervision. For this reason, the mining industry is constantly looking for improvements to existing occupational safety and health programs in order to enhance working conditions for people and equipment. This paper presents the design and implementation of a continuous monitoring device to measure the physiological variables of miners at high altitudes (>2000 m.a.s.l.). Extreme environmental conditions are detrimental for human health; therefore, a continuous control of the workers' vital signs is necessary. The proposed system includes physiological variables such as electrocardiogram, respiratory activity, and body temperature, and environmental variables such as ambient temperature and relative humidity. The noninvasive sensors of the proposed system are embedded all throughout a T-shirt (first layer of protecting clothing) to achieve a functional device and maximum comfort for the users. The device is able to continuously calculate heart and respiration rate, and establish a wireless data transmission to a central monitoring station.

Diabetic foot is a pathology associated with diabetic neuropathy, where the vast majority of diabetic foot infections terminate in surgical intervention; from debridement to amputation of the involved limb. Commonly, diabetic foot infections come from ulceration produced by high-pressure areas under the foot. For this reason, researchers have been working on a continuous measurement system to detect the high-pressure areas in-shoe in a low cost way. This paper presents the design and implementation of a continuous monitoring device to measure the pressure in-shoe. The pressure sensors are built from commercial flexible PCB and a dielectric sheet. The system measures the pressure distribution in 8 points and sends the information by a wireless Bluetooth link to a personal computer and gives information to the patient in real time.

This extended paper presents the development and implementation at a prototype level of a wireless, low-cost system for the measurement of the electrical bioimpedance of the chest with two channels using the AD5933 in a bipolar electrode configuration to measure impedance pneumography. The measurement device works for impedance measurements ranging from 1 Ω to 1800 Ω. Fifteen volunteers were measured with the prototype. We found that the left hemithorax has higher impedance compared to the right hemithorax, and the acquired signal presents the phases of the respiratory cycle with variations between 1 Ω, in normal breathing, to 6 Ω in maximum inhalation events. The system can measure the respiratory cycle variations simultaneously in both hemithorax with a mean error of −0.18 ± 1.42 BPM (breaths per minute) in the right hemithorax and −0.52 ± 1.31 BPM for the left hemithorax, constituting a useful device for the breathing rate calculation and possible screening applications.

This work implements a noninvasive system that measures the movements caused by cardiac activity. It uses unobtrusive Electro-Mechanical Films (EMFi) on the seat and on the backrest of a regular chair. The system detects ballistocardiogram (BCG) and respiration movements. Real data was obtained from 54 volunteers. 19 of them were measured in the laboratory and 35 in a hospital waiting room. Using a BIOPAC acquisition system, the ECG was measured simultaneously to the BCG for comparison. Wavelet Transform (WT) is a better option than Empirical Mode Decomposition (EMD) for signal extraction and produces higher effective measurement time. In the laboratory, the best results are obtained on the seat. The correlation index was 0.9800 and the Bland-Altman limits of agreement were 0.7136 ± 4.3673 [BPM]. In the hospital waiting room, the best results are also from the seat sensor. The correlation index was 0.9840, and the limits of agreement were 0.4386 ± 3.5884 [BPM]. The system is able to measure BCG in an unobtrusive way and determine the cardiac frequency with high precision. It is simple to use, which means the system can easily be used in non-standard settings: resting in a chair or couch, at the gym, schools or in a hospital waiting room, as shown.

Ballistocardiogram (BCG) has been revisited in the last years as an unobtrusive method to detect heart beats. New electromechanical film (EMFi) sensors are now able to detect minimal oscillations in its surface, allowing to detect the mechanical action of the heart as it beats. This has allowed to develop unobtrusive systems for heart rate monitoring to be used as Point-of-Care devices, and to deploy them in waiting rooms, assisted living facilities or at home. In this work, an EMFi sensor is used to measure BCG via the pressure changes on the seat produced by the beating heart. In a lab environment, 34 healthy volunteers are measured under two conditions: at rest and after exercise, simultaneously with ECG. Also, in a clinical environment, 24 volunteers are also measured while waiting. The algorithm looks for the variability of the length transform at different scales or windows to determine a search window to detect beats from the BCG. A second correlation filter helps eliminate false peaks detected due to noise in the signal. Results show that in resting conditions, the mean error between the BCG HR and the reference ECG is only 0.4 beats per minute, with a standard deviation of 1.88. The noise rejection accuracy is 93%. The proposed algorithm can be used to identify beats and issue alarms under abnormal rhythms, providing timely alerts for at-risk population.