Clinical Impact of Patient-ventilator Asynchrony

Chronic respiratory failure (CRF) is an advanced stage of many respiratory diseases marked by an inability of the respiratory system to ensure vital gas exchange. It affects approximately 3.6 million people in France.

Non-invasive ventilation (NIV) remains the reference treatment in hypercapnic respiratory failure because it reduces inspiratory muscles's work and promotes alveolar ventilation.

The establishment of the NIV is carried out most of the time following an episode of acute decompensation revealing an underlying CRF. It is carried out and supervised in hospital departments to optimize the understanding and adherence of the patient to his illness and his treatment.

Thus, monitoring is a key to measure the tolerance and effectiveness of ventilation. Classically, it is based on multi-year medical consultations, blood gases and nocturnal oximetry. In recent years, the reading of detailed data from software integrated into NIV machines has been increasingly used in current practice in association with the monitoring tools already recommended. It provides additional detailed information on compliance, leaks, apnea-hypopnea index (AHI), obstructive events and asynchrony between the patient and their ventilator.

Many patient-ventilator asynchronies have been described in studies with a negative impact on the quality of ventilation, the quality of sleep under NIV and an increased risk of mortality. However, not all asynchronies have the same consequences and are not all felt by the patient

Inclusion criteria

• Women and Men aged of at least 18 years old.
• NIV equipment since 6 months ( at least)
• Chronic respiratory failure requiring NIV equipment defined by clinical symptoms (asthenia, excessive daytime sleepiness, headache, dyspnea) and:

In case of obstructive diseases :

Daytime hypercapnia (PaCO2 > 55 mmHg) or Daytime hypercapnia between 50-54 mmHg associated with nocturnal desaturations (at least 5 min below 88% saturation) or episodes of frequent hypercapnic exacerbations (at least 2 over the last 12 months)

In case of restrictive diseases :

Daytime hypercapnia (PaCO2>6 kPa (kilopascal) or 45 mm Hg) or Nocturnal desaturation (SaO2 < 88%) for at least 5 minutes without obstructive sleep apnea syndrome (OSAS) found or Marker of progression of neuromuscular damage (Maximum inspiratory pressure < 60 cm H2O and forced vital capacity (FVC) less than 50% of theory)

• NIV's start from at least 6 months.
• Patient who did not object to being included in the study.
• Patient in stable condition without exacerbation (for at least 3 months)

Exclusion criteria

• Minor patient
• Pregnant or breastfeeding women
• Adult patient subject to enhanced protection, deprived of liberty by judicial or administrative decision.
• Patient who is physically or psychologically unable to follow the protocol in an informed manner.
• Patient with chronic respiratory failure requiring mechanical ventilation by tracheotomy
• Patient having changed center or service provider (data not available).
• Patient who objected to being included in the study