The importance of controlling [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] throughout long-term noninvasive ventilation

• Published in: Respiratory care 2014-11, Vol.59 (11), p.1671
• Main Authors: Tsuboi, Tomomasa, Oga, Toru, Sumi, Kensuke, Machida, Kazuko, Ohi, Motoharu, Chin, Kazuo
• Format: Article
• Language: English
• Subjects: Artificial respiration; Care and treatment; Patient outcomes; Respiratory insufficiency
• ISSN: 0020-1324
• DOI: 10.4187/respcare.02829

BACKGROUND: The significance of changes in [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during long-term noninvasive ventilation (NIV) on prognosis remains unclear. We aimed to clarify whether stabilizing [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during NIV had a favorable prognostic effect. METHODS: Data from 190 subjects with restrictive thoracic disease and who received long-term NIV were studied retrospectively. The annual change in [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during NIV was determined using a simple linear regression method for each subject who had at least 4 6-month intervals of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] data. Annual changes in [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during long-term NIV and possible confounders were analyzed with discontinuation of long-term NIV as the main outcome. RESULTS: One hundred and twenty-five subjects who had > 4 6-month intervals of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] data were included in the study. [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during long-term NIV decreased in 41 subjects (group 1; < 0 mm Hg/y), increased slightly in 42 subjects (group 2; between 0 and 1.85 mm Hg/y), and increased significantly in 42 subjects (group 3; > 1.85 mm Hg/y). Smaller annual changes in [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] (P < .001) and a control ventilator mode (P = .008) were associated with a significantly higher probability of continuing NIV, compared with decreased [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] 3-6 months after the start of long- term NIV (P = .11). The 10-y probability of continuing NIV was 69% in group 1, 39% in group 2, and 12% in group 3. CONCLUSIONS: A decrease in the annual change of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] during long-term NIV was shown to be a significantly prognostically favorable factor. Efforts to reduce [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] should be made if [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] increases at a greater rate during long-term NIV. Key Words: chronic respiratory failure; hypercapnia; home mechanical ventilation; noninvasive ventilation; [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII]; restrictive thoracic disease.