Emeline Fresnel

Bio: Emeline Fresnel is an academic researcher from Institut national des sciences appliquées de Rouen. The author has contributed to research in topics: Medicine & Physics. The author has an hindex of 3, co-authored 9 publications receiving 48 citations.

Prediction of severe acute exacerbation using changes in breathing pattern of COPD patients on home noninvasive ventilation.

Abstract: Introduction Acute exacerbation of COPD (AECOPD) is associated with poor outcome. Noninvasive ventilation (NIV) is recommended to treat end-stage COPD. We hypothesized that changing breathing pattern of COPD patients on NIV could identify patients with severe AECOPD prior to admission. Methods This is a prospective monocentric study including all patients with COPD treated with long-term home NIV. Patients were divided in two groups: a stable group in which patients were admitted for the usual respiratory review and an exacerbation group in which patients were admitted for inpatient care of severe AECOPD. Data from the ventilator were downloaded and analyzed over the course of the 10 days that preceded the admission. Results A total of 62 patients were included: 41 (67%) in the stable group and 21 (33%) in the exacerbation group. Respiratory rate was higher in the exacerbation group than in the stable group over the 10 days preceding inclusion (18.2±0.5 vs 16.3±0.5 breaths/min, respectively) (P=0.034). For 2 consecutive days, a respiratory rate outside the interquartile limit of the respiratory rate calculated over the 4 preceding days was associated with an increased risk of severe AECOPD of 2.8 (95% CI: 1.4-5.5) (P 1.0845 was associated with an increased risk of severe AECOPD of 4.0 (95% CI: 1.5-10.5) (P=0.001). This assessment had the sensitivity, specificity, positive predictive, and negative predictive values of 81.0, 63.4, 53.1, and 86.7%, respectively. Conclusion Data from NIV can identify a change in breathing patterns that predicts severe AECOPD.

Realistic human muscle pressure for driving a mechanical lung

Abstract: An important issue in noninvasive mechanical ventilation consists in understanding the origins of patient-ventilator asynchrony for reducing their incidence by adjusting ventilator settings to the intrinsic ventilatory dynamics of each patient. One of the possible ways for doing this is to evaluate the performances of the domiciliary mechanical ventilators using a test bench. Such a procedure requires to model the evolution of the pressure imposed by respiratory muscles, but for which there is no standard recommendations. In this paper we propose a mathematical model for simulating the muscular pressure developed by the inspiratory muscles and corresponding to different patient ventilatory dynamics to drive the ASL 5000 mechanical lung. Our model is based on the charge and discharge of a capacitor through a resistor, simulating contraction and relaxation phases of the inspiratory muscles. Our resulting equations were used to produce 420 time series of the muscle pressure with various contraction velocities, amplitudes and shapes, in order to represent the inter-patient variability clinically observed. All these dynamics depend on two parameters, the ventilatory frequency and the mouth occlusion pressure. Based on the equation of the respiratory movement and its electrical analogy, the respiratory muscle pressure was simulated with more consistency in regards of physiological evidences than those provided by the ASL 5000 software. The great variability in the so-produced inspiratory efforts can cover most of realistic patho-physiological conditions.

Defining successful non-invasive ventilation initiation: Data from a real-life cohort.

Abstract: Background and objective: When home non-invasive ventilation (NIV) is initiated, five goals need to be achieved: a daily use >4 h/day, an improvement in gas exchange, health-related quality of life (HRQL) and sleep quality without side effects. Our aim was to assess how frequently these five goals were reached and the factors predictive of achievement. Methods: We conducted a monocentric cohort study that included patients electively established on home NIV over 2 years. HRQL was assessed at baseline and follow-up by the Severe Respiratory Insufficiency questionnaire. Adequate initiation was defined as the achievement of at least three of five goals and successful initiation as the achievement of all. Results: Two-hundred and fifty patients were included at baseline. NIV was initiated for: obesity hypoventilation syndrome (n = 95; 38%), neuromuscular disease (n = 70; 28%), chronic obstructive pulmonary disease (n = 66; 26%) and chest wall disease (n = 19; 8%). At follow-up, measures of all five goals were available in 141 (56%) patients. NIV initiation was adequate for 96 (68%) patients and successful for 12 (9%) patients. In multivariate analysis, a tidal volume ≥ 7.8 ml/kg of ideal body weight was associated with an increased likelihood of adequate NIV initiation (hazard ratio: 5.765 [95% CI:1.824–18.223], p = 0.006]. Improvement in daytime partial arterial carbon dioxide pressure (PaCO2) was not correlated to improvement in HRQL or sleep quality. Severe to very severe NIV-related side effects occurred in 114 (47%) patients and were associated with higher daytime PaCO2 (6.35 ± 1.08 vs. 5.92 ± 0.79 kPa, p < 0.001). Conclusion: Successful home NIV initiation is rarely achieved in real life. HRQL and NIV tolerance should be assessed to improve patient-centred outcomes.

NIV Is not Adequate for High Intensity Endurance Exercise in COPD.

Abstract: Noninvasive ventilation (NIV) during exercise has been suggested to sustain higher training intensity but the type of NIV interface, patient-ventilator asynchronies (PVA) or technological limitation of the ventilator may interfere with exercise. We assessed whether these parameters affect endurance exercise capacity in severe COPD patients. In total, 21 patients with severe COPD not eligible to home NIV performed three constant workload tests. The first test was carried out on spontaneous breathing (SB) and the following ones with NIV and a nasal or oronasal mask in a randomized order. PVA and indicators of ventilator performance were assessed through a comprehensive analysis of the flow pressure tracing raw data from the ventilator. The time limit was significantly reduced with both masks (406 s (197–666), 240 s (131–385) and 189 s (115–545), p 10% was significantly higher with nasal interface (0% versus 33.3%, p < 0.01). NIV did not effectively improve endurance capacity in COPD patients not acclimated to home NIV. This was due to a technological limitation of the ventilator for the oronasal mask and the consequence either of an insufficient pressure support or a technological limitation for the nasal mask.

Randomised crossover trial of telemonitoring in chronic respiratory patients (TeleCRAFT trial*): No impact on hospital admissions and quality of life (QOL)

Abstract: Objective: To assess the impact of home telemonitoring (TM) on health service use and QOL in severe chronic lung disease patients via a randomised crossover trial with 6 months standard clinical care (control group) and 6 months with additional TM (Philips Motiva). Method: Participants - 73 patients (47% male, (mean (SD)) age 63 (12) yrs. 39 with COPD FEV1 0.88(0.54)L and 34 with chronic respiratory failure due to other causes FVC 1.14(0.62)L, who had a hospital admission for an exacerbation within previous 6 months, and used domiciliary oxygen or had a SpO2 l90% during previous acute admission. Patients responded to daily symptom questionnaire and monthly questionnaires on health service use/health related QOL, plus recorded SpO2 daily. Results: Of 61 patients (32 COPD) completing the trial the time to acute admission did not differ between control and TM groups – mean (SD) Control 156 (52) v TM 147 (60) days, p=0.189, and was not affected by intervention order. EuroQol 5D scores, and self-efficacy did not differ between groups. In patients receiving TM first, hospital & home visits increased: self-efficacy decreased. In COPD and anxious patients receiving TM first, depression (HADS) score fell. Conclusion: Telemonitoring added to optimised standard care neither reduced acute admissions, nor improved QOL in severe chronic respiratory patients. In some health care activity increased on TM. Subgroups eg. COPD patients with depression, or anxious patients may benefit. A more nuanced, personalised approach to TM is advisable in chronic severe respiratory patients before a major roll-out. *Funded by NIHR CLAHRC NW London.

Technological advances in home non-invasive ventilation monitoring: Reliability of data and effect on patient outcomes.

Abstract: Home non-invasive mechanical ventilation (NIV) has become a well-established treatment for patients with chronic hypercapnic respiratory failure. NIV monitoring has been developed to evaluate the effectiveness of mechanical ventilation on patient outcomes, with built-in systems providing data on compliance, leaks and respiratory parameters. Although these data seem intuitively useful, two main concerns have been raised in the literature: (i) are they reliable and (ii) to what extent does their use improve patient outcomes. These two concerns are currently relevant since the very recent development of telemonitoring provides the possibility of adjusting ventilator settings remotely, based on the longitudinal assessment of NIV parameters and respiratory variables provided by the system. This may influence the future management strategies of health organizations for patients under home NIV. This narrative review describes technological advances in patient monitoring using home mechanical ventilation with a main focus on data provided by built-in NIV monitoring systems. The use of these systems is discussed, including their advantages and limitations in different clinical situations, and perspectives for long-term patient monitoring are discussed.

Non-Invasive Ventilation as an Adjunct to Exercise Training in Chronic Ventilatory Failure: A Narrative Review.

Abstract: Background Chronic ventilatory failure (CVF) may be associated with reduced exercise capacity. Long-term non-invasive ventilation (NIV) may reduce patients' symptoms, improve health-related quality of life and reduce mortality and hospitalisations. There is an increasing use of NIV during exercise training with the purpose to train patients at intensity levels higher than allowed by their pathophysiological conditions. Objective This narrative review describes the possibility to train patients with CVF and NIV use as a tool to increase the benefits of exercise training. Methods We searched papers published between 1985 and 2018 in (or with the summary in) English language in PubMed and Scopus databases using the keywords "chronic respiratory failure AND exercise," "non invasive ventilation AND exercise," "pulmonary rehabilitation" and "exercise training." Results Exercise training is feasible and effective also in patients with CVF. Assisted ventilation can improve exercise tolerance in different clinical conditions. In patients under long-term home ventilatory support, NIV administered also during walking results in improved oxygenation, decreased dyspnoea and increased walking distance. Continuous positive airway pressure and different modalities of assisted ventilation have been delivered through different interfaces during exercise training programmes. Patients with CVF on long-term NIV may benefit from exercising with the same ventilators, interfaces and settings as used at home. Conclusion We need more randomised clinical trials to investigate the effects of NIV on exercise training in patients with CVF and define organisation and setting.

Remote Patient Monitoring Technologies for Predicting Chronic Obstructive Pulmonary Disease Exacerbations: Review and Comparison.

Abstract: Background: Chronic obstructive pulmonary disease (COPD) is the third leading cause of death by disease worldwide and has a 30-day readmission rate of 22.6%. In 2015, COPD was added to the Medicare Hospital Readmission Reductions Program. Objective: The objective of this paper was to survey the current medical technologies for remote patient monitoring (RPM) tools that forecast COPD exacerbations in order to reduce COPD readmissions. Methods: We searched literature and digital health news to find commercially available RPM devices focused on predicting COPD exacerbations. These technologies were reviewed and compared according to four criteria: forecasting ability, cost, ease of use, and appearance. A rating system was developed to facilitate the evaluation process. Results: As of June 2019, a list of handheld and hands-free devices was compiled. We compared features and found substantial variations. Devices that ranked higher on all criteria tended to have a high or unlisted price. Commonly mass-marketed devices like the pulse oximeter and spirometer surprisingly fulfilled the least criteria. Conclusions: The COPD RPM technologies with most technological promise and compatibility with daily living appear to have high or unlisted prices. Consumers and providers need better access to product information to make informed decisions.

Adaptive Control for Mechanical Ventilation for Improved Pressure Support

Abstract: Respiratory modules are medical devices used to assist patients to breathe. The aim of this article is to develop a control method that achieves exact tracking of a time-varying target pressure, for unknown patient-hose-leak parameters and in the presence of patient breathing effort. This is achieved by an online estimation of the hose characteristics that enables compensation for the pressure drop over the hose. Stability of the closed-loop system is proven, and the performance improvement compared to the existing control strategies is demonstrated by simulation and experimental case studies.