The Geneva Lake Study Update : An Overview of Home Non-Invasive Ventilation 15 Years Later

Study Overview
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Brief Summary
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A multicenter cross-sectional observational study was conducted in the counties of Geneva and Vaud (1'271'957 inhabitants in 2016 and 1'288'090 inhabitants in 2017 ) and included all subjects under home NIV followed by the two university hospitals of Geneva and Lausanne (HUG and CHUV), one private regional general hospital (La Tour Hospital), one pulmonary rehabilitation center (Rolle Hospital) and 38 pulmonologists in private practice (for a total of 43, 18 in Geneva and 20 in Vaud). In Switzerland home NIV can be prescribed, initiated and followed by a pulmonologist in private practice without referring to a hospital center. The coordinating institution for this project was the Geneva University Hospital (HUG). The investigator's goals were to update the prevalence of home NIV, the description of the population involved, the devices used, their settings, compliance, and a large array of technical data to provide a complete photography of home NIV in an area with 30 years of experience in this field. We also aimed to collect data regarding pursuit or interruption of NIV and survival during observation period.

Official Title
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The Geneva Lake Study Update : An Overview of Home Non-Invasive Ventilation 15 Years Later

Conditions
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Home Non-Invasive Ventilation

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients aged over 18 years old undergoing long term home NIV for at least 3 months and living in the Cantons of Geneva or Vaud were eligible for the study. Exclusion Criteria: The only exclusion criteria was invasive ventilation (tracheostomy).
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Adaptive servo-ventilation patients<br>All patients under adaptive servo-ventilation in the Geneva Lake area and details of the specifics indications, population treated and venitator settings | Other: No intervention<br>* No Intervention<br>|
| Barometric and Volumetric patients<br>All patients under barometric and volumetric ventilation in the Geneva Lake area and details of the specifics indications, population treated and venitator settings | Other: No intervention<br>* No Intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnosis | Diagnosis leading to NIV. 5 disease categories with identification of the percentage of patients with SRBD, COPD, Overlap syndrome, OHS, NMD, restrictive chest wall and lung disorders. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Baseline characteristics | Comorbidities, age, gender. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Survival | Analyze short-term mortality rate and risk factors. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-01.05.2021 | 
| Leaks | Investigate modifiable and non-modifiable risk factors asssociated with non intentional air leaks during home non invasive ventilation (NIV). Air leaks are identified by the built in software of the ventilator and clinicians download these data onto a computer. Leaks are expressed in ml or liters. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Implementation of NIV | Is NIV implemented electively or urgently (yes versus no), in an outpatient or input setting (yes vs no), by liberal pulmonologist or hospital center (yes vs no). Data with binary outcome. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Follow-up modalities | Arterial blood gas (ABG): pH, pCO2 (kPa), pO2 (kPa), HCO3 (mmol/l), base excess (mmol/l), SpO2 (%), spirometry: FEV1/FVC % of predicted, FEV1 % of predicted, FVC % of predicted, pulsoxicapnometry: SpO2 (%), time with SpO2 < 90% (%), desaturation index > 3 (%), pCO2 (kPa). All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Ventilators | Home ventilators used (ASV vs barometric vs volumetric), settings: minimal and maximal pressure support (cmH2O), fixed EPAP (cmH20), minimal and maximal EPAP (cmH2O), back-up respiratory rate (cycles/min), data downloaded from the device software: EPAP (cmH2O), IPAP (cmH2O), EPAP 90% (cmH2O), mean pressure support (cmH2O), tidal volume (ml), minute ventilation (L/min), leaks (L/min), apnea index (N/hour), apnea-hypopnea index (N/hour), mean daily use (min/day), interfaces (facial vs nasal vs prongs masks), duration to therapy (expressed in hours). All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). | 01.06.2016-10.07.2018 | 
| Prevalence of home non invasive ventilation (NIV) | Prevalence of home non invasive ventilation. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Barometric and volumetric ventilation versus adaptive servo-ventilation (ASV) | Sub-analysis groups depending on the type of home NIV (barometric and volumetric ventilation versus ASV). All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 | 
| Medical follow-up | To study if there is a statistical significance in the outcomes listed above (diagnostic groups, comorbidities) depending if the medical follow-up is done by a liberal pulmonologist or a hospital center. All data were analyzed using descriptive statistics. Qualitative parameters were described as frequencies and percentages and quantitative parameters were described as mean and standard deviation (SD) or as median and interval interquartile (IQR). Comparisons between groups were performed using chi-square tests or Fisher exact tests for qualitative parameters and analysis of variance (one-way ANOVA) or Kruskal-Wallis tests for quantitative parameters, as appropriate. | 01.06.2016-10.07.2018 |