Obesity hypoventilation syndrome treated with non-invasive ventilation: Is a switch to CPAP therapy feasible?

BACKGROUND AND OBJECTIVE: Obesity hypoventilation syndrome (OHS) can be treated with either continuous positive airway pressure (CPAP) or non-invasive ventilation (NIV) therapy; the device choice has important economic and operational implications. METHODS: This multicentre interventional trial investigated the safety and short-term efficacy of switching stable OHS patients who were on successful NIV therapy for ≥3 months to CPAP therapy. Patients underwent an autotitrating CPAP night under polysomnography (PSG); if the ensuing parameters were acceptable, they were sent home on a fixed CPAP for a 4-6-week period. It was hypothesized that blood gas analysis, PSG parameters and lung function tests would remain unchanged. RESULTS: A total of 42 OHS patients were recruited, of whom 37 patients were switched to CPAP therapy. All patients had a history of severe obstructive sleep apnoea syndrome; chronic obstructive pulmonary disease (COPD) (Global Initiative for Obstructive Lung Disease (GOLD) I/II) was present in 52%. Regarding the primary outcome, 30 of 42 patients (71%, 95% CI: 55-84%) maintained daytime partial pressure of carbon dioxide (PaCO2 ) levels ≤45 mm Hg after the home CPAP period. There was no further impairment in quality of life, sleep parameters or lung function. Interestingly, 24 patients (65%) preferred CPAP as their long-term therapy, despite the high pressure levels used (mean: 13.8 ± 1.8 mbar). After the CPAP period, 7 of 37 patients were categorized as CPAP failure, albeit only due to mild hypercapnia (mean: 47.9 ± 2.7 mm Hg). CONCLUSION: It is feasible to switch most stable OHS patients from NIV to CPAP therapy, a step that could significantly reduce health-related costs. The auto-adjusted CPAP device, used in combination with the analysis of the PSG and capnometry, is a valid titration method in OHS patients.

Is Outpatient Control of Long-Term Non-Invasive Ventilation Feasible in Chronic Obstructive Pulmonary Disease Patients?

BACKGROUND: Long-term non-invasive ventilation (NIV) is an established and increasingly used treatment option for patients with chronic hypercapnic chronic obstructive pulmonary disease (COPD). Following inpatient NIV establishment, inpatient control visits regularly occur thereafter. However, it remains unclear whether such control visits can also be performed in an outpatient setting, which, in turn, would reduce costs, patient burden and the complications related to hospitalization. OBJECTIVES: To investigate an outpatient setting with predefined criteria for hospitalization for patients with chronic hypercapnic COPD. METHODS: An outpatient clinic located within the hospital in the vicinity of the respiratory care unit provided predefined criteria for hospitalization of COPD patients receiving long-term NIV therapy. The results of this setting were retrospectively analysed. RESULTS: A total of 130 outpatient visits (80 patients) were analysed. In 93 cases (71.5%), hospital admission was not necessary, while hospitalization was performed in 37 cases (28.5%). Out of these, 7 cases with acute conditions required prompt hospitalization. Patients without hospitalization had better PaCO2 values (45.40 ± 5.27 vs. 50.05 ± 8.04, p = 0.002) and Severe Respiratory Insufficiency Questionnaire Summary scores (55.54 ± 19.74 vs. 41.82 ± 19.59, p = 0.012). CONCLUSION: Outpatient control of long-term NIV in a hospital setting is feasible and has the capacity to identify stable COPD patients in whom NIV therapy is sufficient according to predefined criteria. These patients may not require hospitalization and may account for more than two thirds of cases.

Assessment of Sleep in Patients Receiving Invasive Mechanical Ventilation in a Specialized Weaning Unit.

INTRODUCTION: A restful sleep is essential for regenerative processes and remains crucial for patients recovering from stressful periods in the intensive care unit. The current study aimed to assess sleep quality in critically ill patients receiving invasive mechanical ventilation within a specialized weaning unit in hospital. METHODS: Tracheotomized subjects undergoing prolonged weaning from mechanical ventilation were included in the study. Polysomnography and gas exchange monitoring was performed during nocturnal ventilation. Subjective evaluation of sleep quality and health-related quality of life were also assessed. RESULTS: Nineteen subjects completed the study protocol. Sleep architecture was highly heterogeneous across individual subjects. Mean total sleep time (TST) was 273 ± 114 min, sleep efficacy 70 ± 23%, slow-wave sleep 25.7 ± 18.4%/TST, rapid eye movement sleep 9.6 ± 7.5%/TST, and arousal index 18.7 ± 12.4/h. No significant difference in sleep quality was found between subjects with successful (N = 7) or unsuccessful (N = 12) weaning. Bicarbonate levels were negatively correlated both with sleep efficacy and sleep quality, that latter of which was subjectively assessed by the subjects using a visual analogue scale. CONCLUSION: Subjects who were undergoing prolonged weaning from mechanical ventilation and admitted to a specialized weaning unit, showed reduced sleep quality with preservation of high amounts of slow-wave sleep.