Volume-targeted versus pressure-targeted noninvasive ventilation in patients with chest-wall deformity: a pilot study.

BACKGROUND: Long-term noninvasive ventilation (NIV) is an effective treatment for patients with chronic respiratory failure due to chest-wall deformity, but it is unknown if the time required for the patient to adjust to long-term NIV depends on whether the NIV is volume-targeted or pressure-targeted. OBJECTIVE: To determine whether volume controlled or pressure controlled NIV is easier to implement in patients with chronic respiratory failure due to chest-wall deformity. METHODS: We randomized 16 ventilator-naïve patients to receive either volume-targeted or pressure-targeted nocturnal NIV. The primary outcome was the number of days needed to successfully establish NIV, defined as adequate adjustment and effective ventilation, as measured with overnight arterial blood gas measurement. RESULTS: Two patients did not tolerate volume NIV, and switched to pressure NIV. NIV was successfully established in both groups after a median 6.0 days. There were no significant differences between the groups at any time point in P(aCO(2)) or P(aO(2)) improvement, nor in changes over time. CONCLUSIONS: There was no significant difference in days needed to successfully establish volume NIV versus pressure NIV in patients with chest-wall deformity. However, two patients switched successfully from volume NIV to pressure NIV, which suggests that they preferred pressure NIV.

Usage of positional therapy in adults with obstructive sleep apnea.

STUDY OBJECTIVES: Many positional therapy (PT) strategies are available for treating positional obstructive sleep apnea (OSA). PT is primarily supplied to selected patients as a secondary treatment option when other therapies have failed. To our knowledge this is the largest study to date to assess effectiveness and long-term compliance of PT (both commercial waistband and self-made constructions, mimicking the tennis ball technique) as primary treatment in patients with different positional OSA severities. METHODS: PT was used by 53 patients, of which 40 patients underwent a follow-up polygraphic evaluation under treatment after a median time interval of 12 weeks. Patients were routinely contacted regarding their clinical status and treatment compliance. RESULTS: PT was successful in 27 out of 40 patients (68%). Overall AHI reduced significantly from a median (interquartile range [IQR]) AHI of 14.5 (10.7-19.6) to 5.9 (3.1-8.5), p < 0.001. The commercial waistband and self-made constructions were equally effective (median (IQR) reduction in overall AHI (Δ9.6 (5.5-11.9) and Δ6.8 (3.2-11.3) respectively), p = 0.22). Short-term compliance was good as most patients used PT more than 7 hours/night (mean 7.2 ± SD 1.4) and more than 6 days/ week (mean 6.5 ± SD 1.3). However, after mean 13±5 months, 26 patients (65%) reported they no longer used PT, especially patients with moderate positional OSA (89%). CONCLUSIONS: On the short-term, PT using the tennis ball technique, is an easy method to treat most patients with positional OSA, showing significant reductions in AHI. Unfortunately, long-term compliance is low and close follow-up of patients on PT with regard to their compliance is necessary.