Autotitrating Versus Standard Non-invasive Ventilation (NIV) in Newly Diagnosed Patients

Autotitrating Non-invasive Ventilation (NIV) Versus Standard NIV; a Randomised Crossover Trial in Patients With Newly Diagnosed Hypoventilation

The aim of the study is to compare the efficacy and tolerance of autotitrating non-invasive ventilation (NIV) versus standard NIV in patients with newly diagnosed nocturnal hypoventilation who have never experienced nocturnal, home NIV.

The aim of the study is to compare the effect of two types of noninvasive ventilator (a small machine that assists breathing) in patients newly diagnosed with nocturnal hypoventilation who are inexperienced in the use of noninvasive ventilation (NIV). NIV is standard therapy for patients with nocturnal hypoventilation. The most common type of NIV is bilevel pressure support which assists patient breathing by delivering different levels of air pressure during inspiration and expiration via a mask covering the nose or nose and mouth. Standard bilevel NIV (VPAP™) has been further developed to create a new automatically adjusting NIV (AutoVPAP™). Automatically adjusting NIV varies the inspiratory air pressure according to the airflow rates generated by the patient. This may improve patient comfort, hours of NIV use and recovery time. Patients over the age of 18 referred to, or under follow up at, the Royal Brompton Hospital who require domiciliary NIV but are inexperienced with use of NIV will be considered for entry into this randomised crossover study. If eligible for inclusion and willing to take part patients will be setup on automatically adjusting NIV or standard NIV, assigned in random order. At the end of one month the patient will be swapped to the alternative NIV for a further one month of domiciliary NIV treatment. At the end of each one month treatment period the patient will undergo overnight polysomnography, transcutaneous CO2 monitoring and 24 hour Holter monitoring.

Respiratory insufficiency, Hypercapnia, Hypoventilation, Sleep, Polysomnography, Hypoxia, Titration, Non Invasive Ventilation

Automatically titrated non-invasive ventilator, with target gross alveolar ventilation and back up respiratory rate determined by learn function. Nocturnal use for one month in patient's home.

Standard non-invasive ventilator with pressure and respiratory rate settings determined by healthcare professional. Nocturnal use for one month in the patient's home.

Overnight oximetry (SaO2) and transcutaneous capnography (PtcCO2) (TOSCA, Linde Medical Sensors, Switzerland) were performed during a sleep a on NIV at the end of each month's NIV therapy.

Overnight oximetry (SaO2) and transcutaneous capnography (PtcCO2) (TOSCA, Linde Medical Sensors, Switzerland) were performed during a sleep a on NIV at the end of each month's NIV therapy.

Overnight oximetry (SaO2) and transcutaneous capnography (PtcCO2) (TOSCA, Linde Medical Sensors, Switzerland) were performed during a sleep a on NIV at the end of each month's NIV therapy.

Overnight oximetry (SaO2) and transcutaneous capnography (PtcCO2) (TOSCA, Linde Medical Sensors, Switzerland) were performed during a sleep a on NIV at the end of each month's NIV therapy. ODI is the number of events per hour that SaO2 drops by >4%.

A full PSG was performed during a sleep a on NIV at the end of each month's NIV therapy. Standard polysomnography analysis was performed by two team members blinded to patient identity and ventilator mode (REP/JJ). Sleep quality was assessed by the Arousal Index (no of arousals/hour)

Summary data from the ventilators were downloaded after each month's therapy, including adherence (hours of use), and ventilator output (nightly mean pressure support, minute ventilation (MV), RR and leak).

Summary data from the ventilators were downloaded after each month's therapy, including adherence (hours of use), and ventilator output (nightly mean pressure support, minute ventilation (MV), RR and leak).

Summary data from the ventilators were downloaded after each month's therapy, including adherence (hours of use), and ventilator output (nightly mean pressure support, minute ventilation (MV), RR and leak).

Summary data from the ventilators were downloaded after each month's therapy, including adherence (hours of use), and ventilator output (nightly mean pressure support, minute ventilation (MV), RR and leak).

Summary data from the ventilators were downloaded after each month's therapy, including adherence (hours of use), and ventilator output (nightly mean pressure support, minute ventilation (MV), RR and leak).

Subjective tolerance of ventilator modes was assessed by 10cm visual analogue scales (VAS) in response to questions on comfort of breath, ease of falling asleep, use of ventilator, and mode preference. VAS was scored from 0-100 for each question (0 - negative and 100 -s positive)

Subjective tolerance of ventilator modes was assessed by 10cm visual analogue scales (VAS) in response to questions on comfort of breath, ease of falling asleep, use of ventilator, and mode preference. VAS was scored from 0-100 for each question (0 - negative and 100 -s positive)

Subjective tolerance of ventilator modes was assessed by 10cm visual analogue scales (VAS) in response to questions on comfort of breath, ease of falling asleep, use of ventilator, and mode preference. VAS was scored from 0-100 for each question (0 - negative and 100 -s positive)

Subjective tolerance of ventilator modes was assessed by 10cm visual analogue scales (VAS) in response to questions on comfort of breath, ease of falling asleep, use of ventilator, and mode preference. VAS was scored from 0-100 for each question (0 - negative and 100 -s positive)

Subjective tolerance of ventilator modes was assessed by 10cm visual analogue scales (VAS) in response to questions on comfort of breath, ease of falling asleep, use of ventilator, and mode preference. VAS was scored from 0-100 for each question (0 - negative and 100 -s positive)

Inclusion Criteria: new clinical diagnosis of nocturnal hypoventilation requirement for long-term domiciliary non-invasive ventilation no previous experience with domiciliary non-invasive ventilation Exclusion Criteria: uncontrolled cardiac failure acute exacerbation of respiratory failure daytime resting PaO2 < 7.5kPa moderate or severe bulbar weakness inability to understand rationale and/or consent form for study