Long-term domiciliary NPPV normalizes hypercapnia and markedly improves hypoxemia as well as polycythemia in OHS patients. In addition, NPPV leads to a significant reduction in restrictive ventilatory disturbance, predominantly by increasing ERV. Application of high inspiratory pressures and good adherence to therapy are presumed to be the basis for the beneficial effects of NPPV in OHS.

Background: Non-invasive positive pressure ventilation (NPPV) is an accepted treatment option for chronic ventilatory failure due to restrictive thoracic disorders. Objective: The impact of ventilation setting and the duration of ventilator use on changes in physiological and functional parameters has not yet been evaluated. Methods: Effects of NPPV on body plethysmographic parameters, blood gas tension and inspiratory muscle function up to 12 months were analyzed in 44 patients with thoracic cage abnormalities in a clinical stable condition. Furthermore, the influence of ventilator parameters and the duration of ventilator use on these changes was determined. Results: A significant improvement in blood gas parameters (PaCO₂, PaO₂ and base excess; p < 0.001), lung volumes (VC, TLC and FEV₁; p < 0.001) and inspiratory muscle function (PI_max, P_0.1; p < 0.01 and p < 0.05) was found after 3.8 ± 0.8 months of treatment. As shown by a subgroup analysis, changes were already achieved within the first 3 months of NPPV and then remained stable over time. Improvements in VC were positively correlated with IPAP (r = 0.55; p < 0.001). Reduction in PaCO₂ was positively correlated with the quotient (IPAP – EPAP)/weight (r = 0.55; p < 0.001). No correlation could be detected between changes in functional parameters and the duration of ventilator use. Conclusions: NPPV can improve blood gas parameters, lung volume and inspiratory muscle function in thoracic restrictive disorders. To best utilize the potential of NPPV treatment, it seems to be more effective to optimize pressure levels than to extend the duration of ventilation.

In severe hypercapnic stable COPD long-term nocturnal NPPV can reduce hyperinflation with sustained improved daytime blood gas parameters.

Fifty-nine patients with bronchogenic carcinoma and 21 patients with nonneoplastic lung diseases underwent intraoperative pleural lavage with 300-ml physiologic saline before (Lavage I) and after resection (Lavage II). The presence of tumor cells in the lavage fluid was established cytologically in 29 patients with bronchogenic carcinoma. Twenty-seven had positive findings in Lavage I and 23 of these also in Lavage II. Two patients had positive findings in Lavage II only. All controls were negative. In all 40% of patients with Stage I bronchogenic carcinoma had positive lavage results. The cumulative two-year survival rate of this group is 40%, which differs significantly (P less than 0.01) from the 97% survival rate of the patients with the same tumor stage whose lavage findings were negative. Detection of tumor cells in pleural cavity washings before resection proves that tumor cells have spread into the pleural cavity. Cytologic examination of an intraoperative pleural lavage should be done when assessing the tumor stage.