Scielo RSS <![CDATA[Research on Biomedical Engineering]]> vol. 34 num. 4 lang. en <![CDATA[SciELO Logo]]> <![CDATA[The use of intervention analysis of the mortality rates from breast cancer in assessing the Brazilian screening programme]]> Abstract Introduction There is a need to develop methods to evaluate public health interventions. Therefore, this work proposed an intervention analysis on time series of breast cancer mortality rates to assess the effects of an action of the Brazilian Screening Programme. Methods The analysed series was the monthly female breast cancer mortality rates from January 1996 to March 2016. The intervention was the establishment of the National Information System on Breast Cancer in June 2009. The Box-Tiao approach was used to build a Global Intervention Model (GIM) composed of a component that fits the series without the intervention, and a component that fits the effect with the intervention. The intervention’s response time was estimated and used to define the length of the residual series to assess the predictive accuracy of the GIM, which was compared to a one-step-ahead forecasting approach. Results The pre-intervention period was fitted to a SARIMA (0,1,2) (1,1,1)12 model and the intervention’s effect to an ARIMA (1,1,0) model. The intervention led to an increase in the mortality rates, and its response time was 24 months. The forecast error (MAPE) for the GIM was 3.14%, and for the one-step-ahead forecast it was 2.15%. Conclusion This work goes one step further in relation to the studies carried out to evaluate the Breast Cancer Screening Programme in Brazil, considering that it was possible to quantify the effects and the response time of the intervention, demonstrating the potential of the proposed method to be used to evaluate health interventions. <![CDATA[Biomechanical alterations of gait on overweight subjects]]> Abstract Introduction Obesity is a major global public health issue and approximately half of the population is classified as overweight. Many studies have investigated gait modification in obese people; however, no research has been carried out in overweight subject┬┤s gait influence. Methods The goal of this study was to identify biomechanical changes on gait in overweight subjects by the application of principal component analysis (PCA). Two groups of adults participated of this study: overweight (n = 9; 25.0 &lt; Body Mass Index &lt; 29.9 kg/m2), and normal-weight (n = 15; 20.0 &lt; Body Mass Index &lt; 24.9 kg/m2. Three-dimensional kinematics of the lower limb and ground reaction forces (GRF) were recorded during gait. PCA was performed on data. Results PCA evidenced statistical differences at the first principal component (PC) of the sagittal ankle movement, anteroposterior and mediolateral GRF, as well as at the third PC of the sagittal hip movement and mediolateral GRF. Overweight subjects walked with reduced ankle plantarflexion at toe-off and reduced hip flexion at the heel strike and at mid swing, as well as a reduced hip extension during push off. Additionally, increased anteroposterior and mediolateral GRF on overweight subjects were observed. Conclusion overweight individuals might adjust their gait characteristics in response to their increased weight to reduce overload lower limbs joints. These gait modifications pointed to a possible increase in the risk of musculoskeletal pathology in this population. <![CDATA[Characterization of a pediatric rotary blood pump]]> Abstract Introduction A ventricular assist device (VAD) is an electromechanical pump used to treat heart failures. For designing the physiological control system for a VAD, one needs a mathematical model and its related parameters. This paper presents a characterization procedure for determining the model parameter values of the electrical, mechanical, and hydraulic subsystems of a pediatric Rotary Blood Pump (pRBP). Methods An in vitro test setup consisting of a pRBP prototype, a motor driver module, an acrylic reservoir, mechanical resistance and tubings, pressure and fluid flow sensors, and data acquisition, processing, and visualization system. The proposed procedure requires a set of experimental tests, and a parameter estimation algorithm for determining the model parameters values. Results The operating limits of the pRBP were identified from the steady-state data. The relationship between the pressure head, flow rate, and the rotational speed of the pRBP was found from the static tests. For the electrical and mechanical subsystems, the dc motor model has a viscous friction coefficient that varies nonlinearly with the flow. For the hydraulic subsystem, the pressure head is assumed to be a sum of terms related to the resistance, the inertance, the friction coefficient, and the pump speed. Conclusion The proposed methodology was successfully applied to the characterization of the pRBP. The combined use of static and dynamic tests provided a precise lumped parameter model for representing the pRBP dynamics. The agreement, regarding mean squared deviation, between experimental and simulated results demonstrates the correctness and feasibility of the characterization procedure. <![CDATA[Sepsis risk assessment: a retrospective analysis after a cognitive risk management robot (Robot Laura┬«) implementation in a clinical-surgical unit]]> Abstract Introduction This study aimed at evaluating the impact of the implementation of a cognitive robot (Robot Laura™) on processes related to the identification and care of patients with risk of sepsis in a clinical-surgical unit of a private hospital in Curitiba-PR. Methods The study data were obtained from the retrospective review of medical records of patients identified with infection and/or sepsis, in the period of six months before and after the implementation of such technology in the hospital. In addition, the Average Attendance Time (AAT) was obtained from the autonomous reading of the robot. Results The average time/median until antibiotic prescription from the first identified sign of infection, with or without sepsis, was 390/77 and 109/58 minutes, respectively, in the six months before and after implementation of the technology. However, this difference was not statistically significant (p = 0.85). Regarding AAT, it was possible to observe a reduction from 305 to 280 minutes when comparing the periods of six months before and after the implementation of the technology (p = 0.02). Conclusion Technologies such as this may be promising in helping healthcare professionals to identify risky situations for patients, as well as in assisting them to optimize the care required. However, further studies, with a greater number of subjects and with different scenarios, are necessary to consistently validate the results found. <![CDATA[SMART: a service-oriented architecture for monitoring and assessing Brazil’s Telehealth outcomes]]> Abstract Introduction Brazilian Telehealth Program was instituted by the Ministry of Health in 2007. Its initial structure was composed by nine telehealth centers administered by public higher education institutions. No standards, processes, applications or quality indicators had been defined since its creation. All this, combined with the decentralization of the centers, led each one of them to develop their own system, with different programming languages and architectures. The lack of regulation and integration of the information with the Ministry of Health made it difficult to evaluate the program. In this context, this paper describes the specification, implementation and validation of an architecture, entitled SMART, to integrate the various telehealth platforms developed by the centers. Such architecture aims to standardize information so that the Ministry of Health can monitor and evaluate the results of Telehealth actions. Methods SMART’s architecture consists of four main components: a web tool for data manipulation; a web service to receive the center’s production data; a component responsible for converting the received data into decision support data; and a component that collects data from external sources to compose the data warehouse. Results The architecture was validated with performance tests, which were executed under extreme workloads. The results of the experiments were summarized in order to attest SMART’s effectiveness. Conclusion The analysis of the results obtained on real data shows that the project’s performance remained stable under the workloads and its high quality was proven due to the absence of errors during the experiments. <![CDATA[Influence of neural mobilization in the sympathetic slump position on the behavior of the autonomic nervous system]]> Abstract Introduction The neural mobilization technique in the sympathetic slump position (NMSS) was based on the slump test, whose purpose was to directly influence the sympathetic trunk and thus provide greater analgesia by sympathetic activation and treat pain syndromes caused by peripheral sympathetic changes. Therefore, as the autonomic nervous system (ANS) is responsible for extrinsic regulation of the cardiovascular system through sympathetic and parasympathetic action, the aim of this study was to investigate the influence of the NMSS technique on the systolic and diastolic blood pressure and heart rate variability in athlete and non-athlete men. Methods Twenty-eight subjects performed the procedure that was divided into three phases: rest; intervention and recovery, lasting 4 minutes and 30 seconds each, totaling a 13-minute and 30 seconds collection time. Results The results showed that the NMSS technique significantly influences the action/activity of the ANS, as there was predominant sympathetic activation during the application of the technique, which was observed by the increase in systolic blood pressure, low frequency (LF), LF/HF ratio and decreased values of high frequency (HF). Conclusion It may be concluded that the neural mobilization technique on the sympathetic slump (NMSS) significantly influences the ANS action/activity. Among the groups there was no statistically significant difference in heart rate variability. It is worth noting that patients with cardiovascular disorders may be at risk if the NMSS technique is applied, since there was an increase in SBP and sympathetic activation during its application in both groups. <![CDATA[The temporal stability of recurrence quantification analysis attributes from chronic atrial fibrillation electrograms]]> Abstract Introduction The temporal behavior of atrial electrograms (AEGs) collected during persistent atrial fibrillation (persAF) directly affects ablative treatment outcomes. We investigated different durations of AEGs collected during persAF using recurrence quantification analysis (RQA). Methods 797 bipolar AEGs with different durations (from 0.5 s to 8 s) from 18 patients were investigated. Four RQA-based attributes were evaluated based on AEG durations: determinism (DET); recurrence rate (RR); laminarity (LAM); and diagonal lines’ entropy (ENTR). The Spearman correlation (ρ) between each duration versus 8 s was calculated. AEG classification was performed following the CARTO criteria (Biosense Webster) and receiving operating characteristic (ROC) curves were created for the RQA variables. Results The RQA variables successfully discriminated the AEGs: the area under the ROC curves were as high as 0.70 for AEGs with 3.5 s or greater. Three types of AEGs were found using these variables: normal, fractionated and temporally unstable. The number of unstable AEGs decreased with longer AEG segments. Different AEG durations significantly affected the RQA variables (P&lt;0.0001), with no statistical difference between the durations 6 s, 7 s and 8 s for DET, LAM and ENTR, and no difference between 7 s and 8 s for RR (P&lt;0.0001). AEGs with 3 s or longer have shown ρ ≥ 80% for all variables. Conclusion The RQA variables have been shown effective in the characterization of AEGs collected during persAF with a shorter duration than current recommendations, which motivates their use for the characterization of atrial substrate during persAF ablation. <![CDATA[FTIR study of Achilles tendinopathy: protein secondary structure changes in tendon post injury]]> Abstract Introduction Tendinopathy, a disease involving tendon inflammation and damage, results in considerable productivity and economic losses for the patient and the society. Currently available diagnosis/ treatment monitoring modalities are less efficacious and highly subjective, underlying the need for better tools. Previously, we have shown that Fourier Transform Infrared (FTIR) spectroscopy has potential in tendinopathy diagnosis/ monitoring, when combined with multivariate statistical analysis. The current study explores the spectral range that gave the best results in statistical analysis, to discover protein secondary structures associated with tendon injury and recovery that can act as markers of disease. Methods Animals (n=60) underwent a surgery in which Achilles tendon were injured by dropping a 20g weight. Rats were divided into three groups (n=20) – control (C), Achilles tendon injury (I) and Achilles tendon injury treated with amniotic membrane fragment treated (T). FTIR spectra were obtained from each group 3, 7, 14, and 28 days post injury/ treatment. Results Triple helix, β-turn, and disordered structure levels differ between control, injured and treated tendons over the time period studied. Parallel β-sheets increase steadily over time in treated tendons compared to control and injured. Conclusion Combined analysis of Triple helix, β- sheets, β-turn, and disordered structure levels may be useful for tendinopathy diagnosis and treatment monitoring. However, further studies in this area are required to confirm the findings. <![CDATA[Impact of regulations on innovation in the field of medical devices]]> Abstract Introduction The regulatory framework and standardized assay methods for classical biomaterials and implantable devices are harmonized at the international level, based on the risk assessment. However, innovative products need the development of more appropriate assay methods and streamline regulatory and scientific evaluation to encourage innovation and ensure more expedite delivery of novel, safe and effective innovative medical devices to patients. The aim of this work is to review the latest focus on the conflicting issues that are involved in the evaluation of recently developed biomaterials and medical devices. Methods This paper is based on a review of the relevant academic literature regarding the field of medical devices over the last ten years (2008-2017). A systematic search was conducted in Medline data base for articles using “medical devices” + “regulations” + “innovation” in the title or abstract. Discussion There is the widespread perception that research and marketing of innovative medical devices are moving swifter, even more so than the issues concerning evaluation methods and regulations. Collaboration among all the stakeholders could contribute to overcome the existing problems in medical device innovation. <![CDATA[From the past to the future of therapeutic orthoses for upper limbs rehabilitation]]> Abstract Introduction The expansion of assistive technologies has been increasing significantly, involving almost all the daily activities, performed by disabled people. One of the highlights to be mentioned is the robotic orthoses, which are being used to amplify movements, to replace amputated limbs, and for a variety of rehabilitation therapies, among others. This study aims to present a review about upper limbs’ orthoses, discussing their weaknesses, potentialities, and pointing out for future perspectives under the motor rehabilitation. Methods For this research, it had been identified 161 papers, based on the bibliographic bases from IEEE and Science Direct, which were filtered by the keywords orthoses, hand, upper-limbs and technology. After the appropriate exclusions, 22 papers were analyzed. Results This review indicates that most of the orthoses have been developed for rehabilitation therapies to be employed by people who have suffered stroke, cerebral palsy or spinal cord injury. This research summarized that the upper limbs movements are effectively produced by electric or pneumatic actuators, having a variety of degrees of freedom. Conclusion This review has shown that, although there are many orthoses styles, ranging from electric to pneumatic actuators; also there are some technical restrictions that prevent their use by most people. However, upper limb orthoses seem to be a great solution for the rehabilitation of people who have suffered a stroke.