Clinical trials for elderly patients with multiple diseases (CHROMED) pilot study

The problem COPD (Chronic Obstructive Pulmonary Disease) is a significant socioeconomic burden which, particularly when associated with comorbidities such as Chronic Heart Failure (CHF), markedly affects patient outcomes. Care models based on telemedicine systems that enable early diagnosis and treatment of exacerbations are advocated to reduce the impact of chronic diseases on patient outcomes and health service costs. CHROMED (www.chromed.eu) is an international EU-funded project aimed at developing a multi-centre clinical trial to evaluate the impact of a new integrated home care approach to reduce care costs and improve quality of life in COPD. The approach We collaborated in a pilot study prior to the main trial which will include 300 patients from seven European countries (Italy, Spain, UK, Estonia, Slovenia, Sweden and Norway) with nine partners. The home monitoring system includes a novel forced oscillation technique (FOT) device for self-measurement of lung mechanics (RESMONPRO DIARY, Restech srl, Italy), a touch screen for collecting patients' symptoms and, where COPD is associated with CHF, by a device for measuring heart rate (HR), blood pressure (BP), pulse oximetry (SpO2) and body temperature (WRIST CLINIC, Medic4all, Israel). Findings The pilot included 16 patients (n=11 COPD, 5 COPD+CHF). The average monitoring period was 48.3±23.4 days resulting in a total of 504 patient days. The percentage of data correctly received within the period was: lung impedance and breathing pattern 90.0%; HR 91.7%, BP 91.7%; SpO2 74.0% and body temperature 71.4%. During the pilot, one patient was treated pharmacologically for an exacerbation of COPD. Offline processing demonstrated that the system identified warning of an exacerbation five days prior to admission. We also analysed qualitative data from patients and professionals about the acceptability of the telemedicine system and the interaction between patients, professionals and the monitoring system. Consequences The data suggest good acceptability and short-term compliance among patients with COPD. Lung function, HR and BP provided the most reliable data. The full RCT is currently under way and will be completed in August 2015

Telemonitoring in Chronic Obstructive Pulmonary Disease (CHROMED). A Randomized Clinical Trial

Rationale: Early detection of COPD exacerbations using tele-monitoring of physiological variables might reduce the frequency of hospitalisation. Objectives: To evaluate the efficacy of home monitoring of lung mechanics by the forced oscillation technique (FOT) and cardiac parameters in older COPD patients with co-morbidities. Methods: This multicentre, randomized clinical trial recruited 312 GOLD grade II-IV COPD patients (median age 71 years [IQR:66-76], 49.6% grade II, 50.4% grade III-IV), with a history of exacerbation in the previous year and at least one non-pulmonary co-morbidity. Patients were randomised to usual care (n=158) or tele-monitoring (n=154) and followed for 9 months. All tele-monitoring patients self-assessed lung mechanics daily and in a subgroup with congestive heart failure (n=37) cardiac parameters were also monitored. An algorithm identified deterioration, triggering a telephone contact to determine appropriate interventions. Measurements and Main results: Primary outcomes were time to first hospitalisation (TTFH) and change in EQ-5D utility index score. Secondary outcomes included: rate of antibiotic/corticosteroid prescriptions, hospitalisation, CAT, PHQ-9 and MLHF questionnaire scores, quality-adjusted life years and healthcare costs. Tele-monitoring did not affect TTFH, EQ-5D utility index score, antibiotic prescriptions, hospitalization rate and questionnaire scores. In an exploratory analysis, tele-medicine was associated with fewer repeat hospitalizations (-54%, p=0.017). Conclusions: In older COPD patients with co-morbidities remote monitoring of lung function by FOT and cardiac parameters did not change TTFH and EQ-5D. Clinical trial registration available at www.clinicaltrials.gov, ID NCT01960907

Effect of stimulating waveform and of data processing on respiratory impedance measurement

Several commercial and custom-made forced oscillation technique (FOT) devices are used to assess respiratory system impedance. The impulse oscillometry system (IOS) is a widespread device, which yields similar, but not identical results to those provided by other FOT systems. Differences may be related to the forcing waveform, the device hardware, or the data processing algorithms. We evaluated the agreement between resistance (Rrs) and reactance (Xrs) measurements while alternating between different forcing waveforms and data processing algorithms

Optimizing positive end-expiratory pressure by oscillatory mechanics minimizes tidal recruitment and distension : an experimental study in a lavage model of lung injury

INTRODUCTION: It is well established that during mechanical ventilation of patients with acute respiratory distress syndrome cyclic recruitment/derecruitment and overdistension are potentially injurious for lung tissues. We evaluated whether the forced oscillation technique (FOT) could be used to guide the ventilator settings in order to minimize cyclic lung recruitment/derecruitment and cyclic mechanical stress in an experimental model of acute lung injury. METHODS: We studied six pigs in which lung injury was induced by bronchoalveolar lavage. The animals were ventilated with a tidal volume of 6 ml/kg. Forced oscillations at 5 Hz were superimposed on the ventilation waveform. Pressure and flow were measured at the tip and at the inlet of the endotracheal tube respectively. Respiratory system reactance (Xrs) was computed from the pressure and flow signals and expressed in terms of oscillatory elastance (EX5). Positive end-expiratory pressure (PEEP) was increased from 0 to 24 cm H2O in steps of 4 cm H2O and subsequently decreased from 24 to 0 in steps of 2 cm H2O. At each PEEP step CT scans and EX5 were assessed at end-expiration and end-inspiration. RESULTS: During deflation the relationship between both end-expiratory and end-inspiratory EX5 and PEEP was a U-shaped curve with minimum values at PEEP = 13.4 ± 1.0 cm H2O (mean ± SD) and 13.0 ± 1.0 cm H2O respectively. EX5 was always higher at end-inspiration than at end-expiration, the difference between the average curves being minimal at 12 cm H2O. At this PEEP level, CT did not show any substantial sign of intra-tidal recruitment/derecruitment or expiratory lung collapse. CONCLUSIONS: Using FOT it was possible to measure EX5 both at end-expiration and at end-inspiration. The optimal PEEP strategy based on end-expiratory EX5 minimized intra-tidal recruitment/derecruitment as assessed by CT, and the concurrent attenuation of intra-tidal variations of EX5 suggests that it may also minimize tidal mechanical stress

Optimizing positive end-expiratory pressure by oscillatory mechanics minimizes tidal recruitment and distension : an experimental study in a lavage model of lung injury

INTRODUCTION: It is well established that during mechanical ventilation of patients with acute respiratory distress syndrome cyclic recruitment/derecruitment and overdistension are potentially injurious for lung tissues. We evaluated whether the forced oscillation technique (FOT) could be used to guide the ventilator settings in order to minimize cyclic lung recruitment/derecruitment and cyclic mechanical stress in an experimental model of acute lung injury. METHODS: We studied six pigs in which lung injury was induced by bronchoalveolar lavage. The animals were ventilated with a tidal volume of 6 ml/kg. Forced oscillations at 5 Hz were superimposed on the ventilation waveform. Pressure and flow were measured at the tip and at the inlet of the endotracheal tube respectively. Respiratory system reactance (Xrs) was computed from the pressure and flow signals and expressed in terms of oscillatory elastance (EX5). Positive end-expiratory pressure (PEEP) was increased from 0 to 24 cm H2O in steps of 4 cm H2O and subsequently decreased from 24 to 0 in steps of 2 cm H2O. At each PEEP step CT scans and EX5 were assessed at end-expiration and end-inspiration. RESULTS: During deflation the relationship between both end-expiratory and end-inspiratory EX5 and PEEP was a U-shaped curve with minimum values at PEEP = 13.4 ± 1.0 cm H2O (mean ± SD) and 13.0 ± 1.0 cm H2O respectively. EX5 was always higher at end-inspiration than at end-expiration, the difference between the average curves being minimal at 12 cm H2O. At this PEEP level, CT did not show any substantial sign of intra-tidal recruitment/derecruitment or expiratory lung collapse. CONCLUSIONS: Using FOT it was possible to measure EX5 both at end-expiration and at end-inspiration. The optimal PEEP strategy based on end-expiratory EX5 minimized intra-tidal recruitment/derecruitment as assessed by CT, and the concurrent attenuation of intra-tidal variations of EX5 suggests that it may also minimize tidal mechanical stress

Response to bronchodilation in children by oscillatory impedance and admittance

Background: when using oscillometry, theoretical reasons support the use of admittance (Y) instead of impedance (Z) for assessing changes in lung mechanics within the same patient (Farré, ERJ,2022), as changes in Y are not affected by upper airway shunt. The current study aims to compare changes in both Y and Z with changes in spirometry due to bronchodilation (BD) in children with persistent asthma. Methods: we retrospectively analyzed data collected on children (6–12 y). Oscillometry (RESMON PRO FULL, Restech srl, Italy) followed by spirometry was performed pre and post 400 mcg salbutamol. A positive response to BD was defined as an increase in FVC or FEV1 >10%predicted (Stanojevic, ERJ, 2022). We computed the AUC of the ROC curve considering absolute and relative (ºseline) changes of oscillometry parameters at 5Hz from Z (module, resistance (R5) and reactance (X5)) and Y (module, conductance (G5) and susceptance (B5)). Results: we included 56 children (Table 1), with 17 showing a positive response to BD. Conclusion: in these subjects with normal baseline FEV1, the agreement with spirometry was similar using Y or Z. The impact of using Y should be evaluated in smaller or more obstructed children, where the impact of the upper airway shunt is higher