Chest
Original ResearchSleep DisordersImpact of Different Backup Respiratory Rates on the Efficacy of Noninvasive Positive Pressure Ventilation in Obesity Hypoventilation Syndrome: A Randomized Trial
Section snippets
Patients
Patients with OHS treated with long-term nocturnal NPPV, in stable clinical condition, and followed by the Division of Pulmonary Diseases of Geneva University Hospital were included in the study. OHS was defined as the association of morbid obesity (BMI > 30 kg/m2) and daytime hypercapnia without any other obstructive or restrictive pulmonary pathology.19 Exclusion criteria were age < 18 years, FEV1/FVC < 70%, history of an acute episode of cardiac and/or respiratory failure within the past 3
Results
Figure 2 shows the flowchart of patient inclusion. All 10 patients included (eight men) had been placed under NPPV after at least one episode of acute hypercapnic respiratory failure. Their characteristics and usual ventilator settings are summarized in Table 1. All had associated severe obstructive sleep apnea-hypopnea syndrome. Nine patients used a facial mask. Four patients used supplemental oxygen.
Based on an analysis of ventilator software over the 2 preceding weeks, the low median BURR
Discussion
This is, to our knowledge, the first study to analyze the impact on sleep structure and treatment efficacy of changes in BURR performed in a random order in a group of patients familiar with NPPV, all suffering from OHS and treated with the same bilevel NPPV device. No other ventilator setting was modified. Results show highly significant differences between the S mode and both S/T modes in terms of respiratory events, and, more specifically, of central and mixed events. Both the occurrence of
Conclusions
In summary, in a short-term trial of patients treated with long-term NPPV for obesity-hypoventilation, using the same NPPV device, changing BURR from an S/T mode with a high or low BURR to an S mode was associated with a highly significant increase in respiratory events, mainly central and mixed events. All respiratory events were lowest under the high-BURR S/T mode. Although our sample size precludes any definite conclusions as to the possible impact of these observations on sleep structure,
Acknowledgments
Author contributions: Dr Contal: contributed to the study design and protocol, recording and analysis of data, and writing and revision of the manuscript.
Dr Adler: contributed to the recording and analysis of data and revision of the manuscript.
Dr Borel: contributed to the recording and analysis of data and writing and revision of the manuscript.
Mr Espa: contributed to the recording and analysis of data and writing and revision of the manuscript.
Dr Perrig: contributed to the writing and
References (32)
- et al.
Changing patterns in long-term noninvasive ventilation: a 7-year prospective study in the Geneva Lake area
Chest
(2003) - et al.
Effect of sleep on patient/ventilator asynchrony in patients undergoing chronic non-invasive mechanical ventilation
Respir Med
(2007) - et al.
Respiratory patterns during sleep in obesity-hypoventilation patients treated with nocturnal pressure support: a preliminary report
Chest
(2007) - et al.
Upper airway obstruction during nasal intermittent positive-pressure hyperventilation in sleep
Lancet
(1991) - et al.
Frequency and volume thresholds for inhibition of inspiratory motor output during mechanical ventilation
Respir Physiol
(1996) - et al.
Effectiveness of controlled and spontaneous modes in nasal two-level positive pressure ventilation in awake and asleep normal subjects
Chest
(1997) - et al.
Impact of volume targeting on efficacy of bi-level non-invasive ventilation and sleep in obesity-hypoventilation
Respir Med
(2009) - et al.
Transcutaneous PCO2 to monitor noninvasive mechanical ventilation in adults: assessment of a new transcutaneous PCO2 device
Chest
(1998) - et al.
Long-term non-invasive ventilation increases chemosensitivity and leptin in obesity-hypoventilation syndrome
Respir Med
(2007) - et al.
Impaired objective daytime vigilance in obesity-hypoventilation syndrome: impact of noninvasive ventilation
Chest
(2007)
Benefits at 1 year of nocturnal intermittent positive pressure ventilation in patients with obesity-hypoventilation syndrome
Respir Med
Importance of ventilator mode in long-term noninvasive positive pressure ventilation
Respir Med
Patterns of home mechanical ventilation use in Europe: results from the Eurovent survey
Eur Respir J
Proposal for a systematic analysis of polygraphy or polysomnography for identifying and scoring abnormal events occurring during non-invasive ventilation
Thorax
Patient-ventilator asynchrony during assisted mechanical ventilation
Intensive Care Med
Susceptibility to periodic breathing with assisted ventilation during sleep in normal subjects
J Appl Physiol
Cited by (0)
Funding/Support: This study was supported by an unrestricted grant from the Pulmonary League of Geneva (www.lpge.ch), the Swiss Society of Pulmonology, and the Lancardis Foundation.
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.
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Drs Rodenstein, Pépin, and Janssens are from the SomnoNIV group