Real-time Feedback System Research Articles

Towards Embedded System for Real-time Feedback in Table Tennis Based on 2.4 GHz Wireless Sensor

Towards Embedded System for Real-time Feedback in Table Tennis Based on 2.4 GHz Wireless Sensor

Quantitative Estimations of Thermal Damage in Skin Tissue Using Monte Carlo Simulation of Polarized Light

Thermal treatment has been used for collagen tightening and tissue contour enhancement. It is important to monitor the condition of collagenous tissue during and immediately after thermal treatment. Collagen denaturation changes the optical properties such as scattering coefficient and anisotropy. In this study, Monte Carlo simulation of polarized light was used to calculate the degree of linear polarization (DOLP) of backscattered light from thermally damaged porcine skin, and the Mueller matrix was calculated to verify the result of DOLP. We observed a decrease in the DOLP and a significant change in the radial distribution of the Mueller matrix elements at temperatures ranging from 55 to 65°C. This could be attributed to the increase in scattering coefficient and decrease in anisotropy caused by thermal denaturation in the tissue. The DOLP method has a potential implementation as a real-time closed-loop feedback system for use in various thermal treatment methods through measuring changes in optical properties of target tissues.

A flexible pressure sensor could correctly measure the depth of chest compression on a mattress

BackgroundFeedback devices are used to improve the quality of chest compression (CC). However, reports have noted that accelerometers substantially overestimate depth when cardiopulmonary resuscitation (CPR) is performed on a soft surface. Here, we determined whether a flexible pressure sensor could correctly evaluate the depth CC performed on a mannequin placed on a mattress. MethodsChest compression was performed 100 times/min by a compression machine on the floor or a mattress, and the depth of CC was monitored using a flexible pressure sensor (Shinnosukekun) and CPRmeter™. The depth of machine-performed CC was consistently 5cm. We compared data from the feedback sensor with the true depth of CC using dual real-time auto feedback system that incorporated an infrared camera (CPR evolution™). ResultsOn the floor, the true depth of CC was 5.0±0.0cm (n=100), or identical to the depth of CC performed by the machine. The Shinnosukekun™ measured a mean (±SD) CC depth of 5.0±0.1cm (n=100), and the CPRmeter™ measured a depth of 5.0±0.2cm (n=100). On the mattress, the true depth of CC was 4.4±0.0cm (n=100). The Shinnosukekun™ measured a mean CC depth of 4.4±0.0cm (n=100), and the CPRmeter™ measured a depth of 4.7±0.1cm (n=100). The data of CPRmeter™ were overestimated (P<.0001 between the true depth and the CPRmeter™-measured depth). ConclusionThe Shinnosukekun™ could correctly measure the depth of CC on a mattress. According to our present results, the flexible pressure sensor could be a useful feedback system for CC performed on a soft surface.

Software defined healthcare networks

With the increasingly serious problem of the aging population, creating an efficient and real-time health management and feedback system based on the healthcare Internet of Things (HealthIoT) is an urgent need. Specifically, wearable technology and robotics can enable a user to collect the required human signals in a comfortable way. HealthIoT is the basic infrastructure for realizing health surveillance, and should be flexible to support multiple application demands and facilitate the management of infrastructure. Therefore, enlightened by the software defined network, we put forward a smart healthcare oriented control method to software define health monitoring in order to make the network more elastic. In this article, we design a centralized controller to manage physical devices and provide an interface for data collection, transmission, and processing to develop a more flexible health surveillance application that is full of personalization. With these distinguished characteristics, various applications can coexist in the shared infrastructure, and each application can demand that the controller customize its own data collection, transmission, and processing as required, and pass the specific configuration of the physical device. This article discusses the background, advantages, and design details of the architecture proposed, which is achieved by an open-ended question and a potential solution. It opens a new research direction of HealthIoT and smart homes.

The Effects of Eco-Feedback Design on Users’ Immediate Reactions to Water Conservation

Background : Eco-feedback is a common solution for changing people’s behavior to reduce resource consumption. The design of eco-feedback becomes especially important in the context where users do not pay for the resources like in the case of public toilets. As people interact with these environments for a short time, it is critical to guide people’s behavior immediately in the moment. Methods : Our research aimed to investigate the effect of the designs of eco-feedback on users’ immediate reactions to water conservation. We conducted an in-lab experiment with 40 users on 32 designs of water consumption feedback display. To develop the design stimuli, we applied four design attributes suggested from a prior study. To present the feedback designs, a real-time water feedback system named SaveDrops was developed. While participants experienced the feedback designs, the amount of water consumption was measured by the prototype system. The participants’ reflections on the experience were gathered through surveys and post-interviews. Result : The experiment revealed that the graphical representation of water consumption was significantly more effective than the numeric representation. Frequent auditory feedback was also more effective than occasional feedback. Among the design stimuli, the most effective one for immediate water conservation was revealed as: the amount of consumed water, which was interpreted in a comparative percentage for other people, represented in a bar graph, and with beeping sound. Conclusions : This paper contributes to the sustainable design fields by investigating the effects of various eco-feedback designs on users’ immediate reactions. We expect that the designs and their effects can be good references for sustainable design practices. In particular, practitioners can refer to the design guidelines when designing products for reducing resource consumption. Also, they can select a design alternative by considering the effects.

Day 1. Free Communications – Sport and Performance

Gait-retraining using real time visual feedback is an effective intervention for modifying factors associated with overuse injuries in runners (Noehren et al., 2011, Br J Sports Med, 45, 691-696). Decreased knee flexion at initial contact has been associated with increased vertical loading rates, an identified risk factor for tibial stress fracture (Milner et al., 2006, Med Sci Sports Exer, 38, 323-328). Therefore, the aim of this study was to evaluate the effectiveness of a gait retraining program designed to increase knee flexion angle at initial contact . Following institutional ethics approval, eight injury-free recreational runners (5 females and 3 males; mean ± SD: age 24 ± 6.5 years) with an initial knee contact angle lower than 12° at initial screening, were recruited. In a pre-test, participants completed five trials of overground running on a 16m runway at a self-selected speed (mean speed 2.8 m.s-1, SD = 0.5) while force plate data (1000Hz) and sagittal plane video (100Hz) were captured. Participants then completed six 15 minute treadmill-based gait-retraining sessions, over two weeks. Running at a self-selected speed, participants received real-time visual feedback on knee angle via a bespoke system comprising a Microsoft Kinect and custom-written software. The system encouraged participants to maintain an initial knee contact angle of greater than 16°, with feedback gradually removed over the last three sessions. Post-intervention, the overground testing protocol was repeated. The effect of the intervention on knee angle at initial contact, peak knee angle during stance, average and instantaneous vertical loading rates was assessed using paired t-tests and Cohen's d effect sizes (d). Knee flexion at initial contact increased from 8.0° ± 2.8° pre to 19.4° ± 2.0° post retraining (P < 0.001, d = 4.7), while maximum knee flexion increased from 39.2° ± 3.1° to 48.6° ± 4.7° following the intervention (P < 0.001, d = 2.3). Average vertical loading rate and instantaneous vertical loading were both reduced following the gait retraining programme with reductions of 30% (P < 0.001, d =1.2), and 25% (P < 0.001, d = 1.1), respectively. Results showed the six session intervention was successful in altering knee kinematics and reducing vertical ground reaction forces, suggesting gait-retraining to be an effective means of reducing injury risk. The real-time feedback system is low cost and portable offering scope for the use of gait-retraining outside of the laboratory in the clinic or home.

The analysed effectiveness of emergency medical actions taken by medical staff in a prehospital sudden cardiac arrest in the years 2012–2014 in central-east region of Poland

s / Resuscitation 96S (2015) 43–157 71 Table 2 The differences in EtCO2 (kPa) between manual CPR and ACD-CPR during real-time audio-visual feedback system defibrillator guided cardiopulmonary resuscitation. Patient ACD-CPR Manual CPR p-Value Median IQR Median IQR 1 2.13 2.10–2.43 3.40 3.33–3.57 <0.001 2 3.73 3.20–4.07 3.14 2.93–3.20 0.001 3 4.80 4.02–5.17 4.67 4.13–5.07 0.861 4 4.20 4.00–4.67 4.34 4.10–5.00 0.312 5 4.67 4.00–5.47 4.27 3.63–5.07 0.121 6 4.13 3.87–4.40 3.94 3.47–4.13 0.034 7 3.73 3.60–4.00 4.00 3.77–4.37 <0.001 8 5.14 4.50–5.37 5.20 4.67–5.54 0.668 9 2.13 2.00–2.47 1.60 1.60–2.27 0.001 10 4.20 3.84–4.67 4.20 3.63–5.20 0.414 p-Value: Mann–Whitney U test. during the cycles. The differences in the level of EtCO2 between manual CPR and ACD-CPR were compared within every patient separately to minimize the confounding factors between the cases. Results: The quality measurements of resuscitation attempts withmanual CPRversusACD-CPRare shown inTable 1.Manual CPR showed a trend in increasing EtCO2 compared to ACD-CPR (Fig. 1), but this effect did not reach statistical significance in 5 out of 10 patients (Table 2). Conclusions: This study suggests that manual ACD-CPR is not superior to quality-controlled CPR provided using a real-time audio-visual feedback system defibrillator. To the best of our knowledge, this is the first study to measure the quality when comparing these two resuscitation methods.

Stone/tissue differentiation for holmium laser lithotripsy using autofluorescence.

Holmium laser lithotripsy is a safe and effective method to disintegrate urinary stones of all compositions in an endoscopic procedure. However, handling and safety could be improved by a real-time feedback system permanently monitoring the position of the treatment fiber. The laser is fired only when the fiber is identified as being placed in front of stone. This work evaluates the potential of fluorescence detection with an excitation wavelength of 532 nm for this purpose. A fiber-based fluorescence measurement was set-up to acquire autofluorescence signals from several human renal calculi, artificial stones, and porcine tissue samples (renal calix and ureter). Three different approaches were investigated. First, experiments were performed with a pulsed laser source with a wavelength of 532 nm, pulse energy 36.5 ± 1 μJ, pulse duration 1.2 ± 0.5 nanoseconds, and a repetition rate of 1 kHz with 15 urinary concretions. In the second step, a series of measurements on 42 human urinary calculi samples was carried out using low power continuous wave excitation of 0.4 ± 0.1 mW. Fluorescence was also measured simultaneously to stone fragmentation by holmium laser pulses (pulse energy 240 ± 50 mJ, repetition rate 10 Hz). Finally, a modulated excitation/detection scheme (lock-in technique) was implemented to render fluorescence detection insensitive to white background light. Unlike porcine renal calix, ureter, and artificial stone human urinary calculi show a strong fluorescence signal when excited with 532 nm. With pulsed excitation on urinary stone (20,000 ± 11,000) counts were registered at 587 nm with the CCD-array of a grating spectrometer in an integration time of 50 milliseconds. Tissue gave lower count rates of ≤(5,500 ± 1,100) even with longer integration times (500 milliseconds/1 second). With a cw excitation power of 0.4 mW (13,000 ± 11,000) counts were registered in an integration time of 200 milliseconds at 587 nm (porcine renal calix: (770 ± 340)). Modulated excitation (66 Hz) with an average power of 0.3 mW and detection with a photodiode resulted in a lock-in amplifier signal of 1.5-4.3V on stone (background and skin: <0.5V). With the lock-in technique, autofluorescence from stones can be detected with only the average excitation power of a green aiming beam overlaid to the Ho:YAG-laser beam (power ≤ 1 mW). Since tissue shows very little autofluorescence when excited with 532 nm, this fluorescence signal enables monitoring of the correct position of the treatment fiber during ureteroscopic procedures.

A System for Real-Time Feedback to Improve Gait and Posture in Parkinson's Disease.

For people with Parkinson's disease (PD), gait and postural impairments can significantly affect their ability to perform activities of daily living. Presentation of appropriate cues has been shown to improve gait in PD. Based on this, a treadmill-based system and experimental paradigm were developed to determine if people with PD can utilize real-time feedback (RTFB) of step length or back angle (uprightness) to improve gait and posture. Eleven subjects (mean age 67 ± 8 years) with mild-to-moderate PD (Hoehn and Yahr stage I-III) were evaluated regarding their ability to successfully utilize RTFB of back angle or step length during quiet standing and treadmill walking tasks during a single session in their medication-on state. Changes in back angle and step length due to feedback were compared using Friedman nonparametric tests with Wilcoxon Signed-Rank tests for post-hoc comparisons. Improvements in uprightness were observed as an increase in back angle during quiet standing (p = 0.005) and during treadmill walking (p = 0.005) with back angle feedback when compared to corresponding tasks without feedback. Improvements in gait were also observed as an increase in step length (p = 0.005) during step length feedback compared to tasks without feedback. These results indicate that people with mild-to-moderate PD can utilize RTFB to improve upright posture and gait. Future work will investigate the long-term effects of this RTFB paradigm and the development of systems for clinical or home-based use.

Neurocognitive therapeutics: from concept to application in the treatment of negative attention bias.

There is growing interest in the use of neuroimaging for the direct treatment of mental illness. Here, we present a new framework for such treatment, neurocognitive therapeutics. What distinguishes neurocognitive therapeutics from prior approaches is the use of precise brain-decoding techniques within a real-time feedback system, in order to adapt treatment online and tailor feedback to individuals’ needs. We report an initial feasibility study that uses this framework to alter negative attention bias in a small number of patients experiencing significant mood symptoms. The results are consistent with the promise of neurocognitive therapeutics to improve mood symptoms and alter brain networks mediating attentional control. Future work should focus on optimizing the approach, validating its effectiveness, and expanding the scope of targeted disorders.

Modelling environmental and cognitive factors to predict performance in a stressful training scenario on a naval ship simulator

Professionals working in risky or emergency situations have to make very accurate decisions, while the quality of the decisions might be affected by the stress that these situations bring about. Integrating task feedback and biofeedback into computer-based training environments could improve trainees' stress-coping behaviour. This paper presents and assesses a refined version of the cognitive performance and error (COPE) model that describes the effects of stressful events on decisions as a foundation for such a support tool. Within a high-fidelity simulator of a ship's bridge at the Royal Netherlands Naval College, students of the naval college (n = 10) were observed while completing a 2-h-long shadowing and boarding operation combined with a search-and-rescue operation. For every action, variables were measured: objective and subjective task demand, challenge and threat appraisal, and arousal based on heart rate and heart rate variability. The data supported the COPE model and were used to create predictive models. The variables could provide minute-by-minute predictions of performance that can be divided into performance rated by experts and errors. The predictions for performance rated by experts correlated with the observed data (r = 0.77), and 68.3 % of the predicted errors were correct. The error predictions concern the chances of making specific errors of communication, planning, speed, and task allocation. These models will be implemented into a real-time feedback system for trainees performing in stressful simulated training tasks.

A Real-Time Analysis and Feedback System for Quality Control of Dam Foundation Grouting Engineering

Real-time analysis and feedback systems play a vital role in obtaining good results from grouting processes. However, when there are intense construction schedules and complex geological structures, it is difficult for existing systems to provide to site engineers, prior to the borehole construction, prompt and accurate feedback, such as detailed geological information about grouting boreholes, which limits the use of such systems in practical applications. This paper proposes combining a three-dimensional (3D) geological model with real-time data collection technology in a system for both monitoring grouting, and providing analysis and feedback. This integrated grouting model, which comprises the geological model, the grouting borehole model and the grouting parameter database set, can be coupled and associated dynamically with grouting data. Additionally, the following methods are applied in this system: real-time grouting data processing and a monitoring alarm, prediction and visualization of geological conditions, forecasting of rock uplift, and visualization analysis of grouting parameters. The application of this system in Hydropower Project A, China is used as a case study. The predictions of geological conditions are closely matched with the actual situation, and this system can be used to monitor construction processes remotely and to help site engineers to design reasonable construction plans, optimize layouts for grouting boreholes and adjust construction measures.

Ergodesk-desktop Ergonomics Using the New Quadratic Search Algorithm

Ergonomics is nothing but the rules governing the workplace. ErgoDesk is the ultimate drug-free way to look after your spine and health. This research provides an interesting and realistic solution towards achieving the goal maintaining good health. Physical stress at the work environment can reduce efficiency of the individuals at work. Ergonomics is described as the rules to be adapted by one, at work environment. The main focus of ergonomics is to reduce the physical stress caused by factors like improper body mechanics, repetitive motor movements, static positions, vibrations, lighting and impact or contact with objects. Henceforth, through this paper, we present a distinct tool called the “ERGODESK”, which could be useful for monitoring a computer user’s posture and activities. In this study, we present a real time feedback system for detecting people and their postures and generating summaries of postures and activities over a specified period of time. The system runs reliably on different people and under any lighting. The fundamental challenge, to detect the change in user’s posture most accurately in the least time, has been analysed and a solution in form of new Quadratic Search Algorithm has been proposed. The system captures an image of the user at regular intervals of time, carries out certain pre-processing steps and then checks for a change in user’s posture by comparing it with a reference image acquired previously in series of steps as per the New Quadratic Search algorithm. Then the user is notified about the change of his ergonomic posture.

Integrating persuasive technology with energy delegates for energy conservation and carbon emission reduction in a university campus

This paper presents the results of energy conservation strategies implemented in the University residential halls to address energy consumption issues, using IPTED (Integration of Persuasive Technology and Energy Delegate) in the student residential halls. The results show that real time energy feedback from a visual interface, when combined with energy delegate can provide significant energy savings. Therefore, applying IPTED reveals a significant conservation and carbon emission reduction as a result from the intervention conducted in student hall of residents comprising of 16 halls with 112 students. Overall, the intervention revealed that, the use of real time feedback system reduced energy consumption significantly when compared to baseline readings. Interestingly, we found that the combination of real time feedback system with a human energy delegate in 8 halls resulted in higher reduction of 37% in energy consumptions when compared to the baseline amounting to savings of 1360.49 kWh, and 713.71 kg of CO2 in the experimental halls. On the contrary, the 8 non-experimental halls, which were exposed to the real time feedback and weekly email alert, resulted in only 3.5% reduction in energy consumption when compared to the baseline, amounting to savings of only 165.00 kWh, and 86.56 kg of CO2.

Automatic calibration of trigger delay time for cardiac MRI

This study aimed to automatically identify the cardiac rest period using a rapid free-breathing (FB) calibration scanning procedure, and to determine the optimal trigger delay for cardiac imaging. A standard deviation (SD) method was used to rapidly identify cardiac quiescent phases employing multiphase cine cardiac images. The accuracy of this method was investigated using 46 datasets acquired from 22 healthy volunteers. The possibility of using a low-resolution FB method to rapidly acquire cine images was also evaluated. The reproducibility and accuracy of the trigger delay obtained using the rapid calibration scanning process were assessed before its application to a real-time feedback system. The real-time trigger delay calibration system was then used to perform T1 -weighted, short-axis imaging at the end of the cardiac systolic period. Linear regression analysis of the trigger times obtained using the SD method and a reference method indicated that the SD algorithm accurately identified the cardiac rest period (linear regression: slope = 0.94-1, R(2) = 0.68-0.84). Group analysis showed that the number of pixels in the left ventricular blood pool in images acquired at the end-systolic time calculated in real time was significantly lower than in those acquired 50 ms in advance or later (p < 0.01, paired t-test). The low-resolution FB imaging method was reproducible for the calibration scanning of an image in a vertical long-axis slice position (average SD of trigger times, 16-39 ms). Combined with rapid FB calibration scanning, the real-time feedback system accurately adjusted the trigger delay for T1 -weighted short-axis imaging. The real-time feedback method is rapid and reliable for trigger time calibration, and could facilitate cardiac imaging during routine examination.

Chest compression depth after change in CPR guidelines—Improved but not sufficient

AimsCardiopulmonary resuscitation is one of the most vital therapeutic options for patients with cardiac arrest. Sufficient chest compression depth turned out to be of utmost importance to increase the likelihood of a return of spontaneous circulation. Furthermore, the use of real-time feedback-systems for resuscitation is associated with improvement of compression quality. The European Resuscitation Council changed their recommendation about minimal compression depth from 2005 (40mm) to 2010 (50mm). The aim of the present study was to determine whether this recommendation of the new guidelines was implemented successfully in an emergency medical service using a real-time feedback-system and to what extend a guideline-based CPR training leads to a “change in behaviour” of rescuers, respectively. Methods and resultsThe electronic resuscitation data of 294 patients were analyzed retrospectively within two observational periods regarding fulfilment of the corresponding chest compression guideline requirements: ERC 2005 (40mm) 01.07.2009–30.06.2010 (n=145) and ERC 2010 (50mm) 01.07.2011–30.06.2012 (n=149). The mean compression depth during the first period was 47.1mm (SD 11.1) versus 49.6mm (SD 12.0) within the second period (p<0.001). With respect to the corresponding ERC Guidelines 2005 and 2010, the proportion of chest compressions reaching the minimal depth decreased (73.9% vs. 49.1%) (p<0.001). There was no correlation between compression depth and patient age, sex or duration of resuscitation. ConclusionsThe present study was able to show a significant increase in chest compression depth after implementation of the new ERC guidelines. Even by using a real-time feedback system we failed to sustain chest compression quality at the new level as set by ERC Guidelines 2010. In consequence, the usefulness of a fixed chest compression depth should be content of further investigations.

Modeling and Analysis for CPS Physical Entities Based on Spatio-Temporal Petri Net

CPS is a kind of multidimensional complex system fused with computing system, physical environment and network environment. CPS achieves the target of real-time perception and dynamic control of physical environment by the organic integration of 3C operations and depth of their cooperation. However, CPS also faces enormous challenges. Since CPS is a kind of large, heterogeneous, distributed and real-time feedback system which is integrated with multiple heterogeneous subsystem via the network, its system complexity is above the general information system. And the introduction of physical entities control system brings tremendous difficulties to development as well as its system complexity. This paper conducts a detailed analysis of the characteristics of the physical aspects of CPS and studies CPS’s physical entities of the properties and their location changes process in-depth. Then we propose a formal modeling method of physical entities in CPS by constructing a Spatial-Temporal Petri net model introducing space factor into the traditional Timed Petri net, which not only able to describe logical and time-level the behavior of physical entities, but also the changes of state caused by the position change of the physical entity. At last an example of robot control system proves the effectiveness of spatial and temporal Petri net models.

A Novel, Real-time Biomechanical Feedback System for Use in Rowing

Biomechanical feedback in water-based rowing is traditionally presented as paper reports or video overlaid with data once a session has been completed. Research into the provision of extrinsic feedback in sport suggests that real-time feedback can lead to skill acquisition and, when appropriately applied, lead to skill retention during competition and therefore a positive performance outcome. This paper presents a novel system architecture that delivers real-time feedback using commercially available off-the-shelf components. The development of a rowing specific system to test a range of feedback strategies is presented, including fading feedback, mixing feedback modalities and varying of the frequency and timing of feedback. MoSync, a cross-platform smartphone development language, was used to write the client application while the server was written as an embedded application in C and Lua that ran on top of the OpenWrt open-source router operating system. Data was transmitted wirelessly across a Wi-Fi network. A human-centred design process was led by a group of high-performance athletes and coaches and the system was shown to deliver data to up to 10 clients simultaneously. Future research will investigate the efficacy of a variety of different feedback strategies to rowers.

Abstract 275: A Randomized Controlled Trial of Compression Rates (COMPRATE trial) During Cardiopulmonary Resuscitation

Purposes: This prospective, randomized, multicenter-, controlled trial was conducted to compare the efficacy of CPR with compression rate of 100/min to CPR with compression rate of 120/min in patients with cardiac arrest. Methods: Patients with non-traumatic out-of-hospital cardiac arrest whose age is equal and over 19 years old were randomized into two groups when the patient arrived at emergency department. The patients received manual CPR either a compression rate of 100 /min (CPR-100 group) or a compression rate of 120/min (CPR-120 group). Chest compressions were performed by pre-trained AHA certified healthcare providers according to guidance of metronome and a real-time CPR measurement feedback system. Quality of chest compression was assessed by reviewing the depth and rate of compressions recorded in the high quality electronic monitoring system of the defibrillator. The case was excluded if the accuracy of the depth and rate of chest compressions could not be maintained over 90%. The primary outcome measure was sustained return of spontaneous circulation (ROSC). The secondary outcome measures were survival discharge from the hospital, 1-month survival, and 1-month survival with good functional status, categorized as a score of 2 or less on the cerebral performance category. Results: 470 patients were enrolled in the study. 221 patients were assigned to CPR-100 group and 249 patients assigned to CPR-120 group. A total of 136 patients (61.5 %) in the CPR-100 group and 156 patients (62.7 %) in the CPR-120 group were included in the analysis. In comparison of primary outcome, 69 patients (50.7%) in CPR-100 group and 67 patients (42.9%) in CPR-120 group had ROSC (p=0.183). In secondary outcome measures, the rates of survival discharge from the hospital, 1-month survival, and 1-month survival with good functional status were not different between two groups (16.9% vs. 12.8%, p=0.375; 12.5% vs. 6.4%, p=0.073; 5.9% vs. 2.6%, p=0.154). Conclusions: In patients with out-of-hospital non-traumatic cardiac arrest resuscitated in emergency department, no differences in the resuscitation outcomes were found between those who received CPR with a compression rate of 100/min and those who received CPR with a compression rate of 120/min.

Real-time audiovisual feedback system in a physician-staffed helicopter emergency medical service in Finland: the quality results and barriers to implementation

ObjectivesTo evaluate the quality of cardiopulmonary resuscitation (CPR) in a physician staffed helicopter emergency medical service (HEMS) using a monitor-defibrillator with a quality analysis feature. As a post hoc analysis, the potential barriers to implementation were surveyed.MethodsThe quality of CPR performed by the HEMS from November 2008 to April 2010 was analysed. To evaluate the implementation rate of quality analysis, the HEMS database was screened for all cardiac arrest missions during the study period. As a consequence of the observed low implementation rate, a survey was sent to physicians working in the HEMS to evaluate the possible reasons for not utilizing the automated quality analysis feature.ResultsDuring the study period, the quality analysis was used for 52 out of 187 patients (28%). In these cases the mean compression depth was < 40 mm in 46% and < 50 mm in 96% of the 1-min analysis intervals, but otherwise CPR quality corresponded with the 2005 resuscitation guidelines. In particular, the no-flow fraction was remarkably low 0.10 (0.07, 0.16). The most common reasons for not using quality-controlled CPR were that the device itself was not taken to the scene, or not applied to the patient, because another EMS unit was already treating the patient with another defibrillator.ConclusionsWhen quality-controlled CPR technology was used, the indicators of good quality CPR as described in the 2005 resuscitation guidelines were mostly achieved albeit with sufficient compression depth. The use of the well-described technology in improving patient care was low. Wider implementation of the automated quality control and feedback feature in defibrillators could further improve the quality of CPR on the field.Trial registrationClinicalTrials.gov (NCT00951704)