Effects of non-invasive ventilation on renal and endothelial function in patients with respiratory failure.

Non-invasive positive pressure ventilation (NIV) is now an indispensable safeguard in the management of many pathologies. However, sometimes the positive end-expiratory pressure (PEEP) showed harmful effects on renal function, although effects on renal hemodynamic are unclear. We aimed at evaluating the effects of NIV on renal and endothelial function, in patients with chronic or acute respiratory failure. We performed a longitudinal, prospective, interventional study. We enrolled 17 hospitalized and non-hospitalized patients (11 males) with indication to NIV and stable hemodynamic parameters. Patients were treated with NIV and followed up at T0, at T1 (at the end of the NIV cycle) and at T2 (fifteen days after). 17 patients (11 males) with a mean age of 71.94 ± 14.89 years were enrolled. A significant increase in flow mediated dilation (FMD) was found (p = 0.004). We showed a significant improvement, after NIV, in the values of pH (p = 0.0002), pCO2 (p = 0.0001), pO2 (p = 0.04), lactates (p = 0.04), sO2 (p = 0.02) and in the P/F Ratio (p = 0.004). We also showed a significant reduction of serum glucose (p = 0.01) and a significant increase of serum chlorine (p = 0.047), while we did not report a significant increase of creatinine (p = 0.297) or a significant change in diuresis. In our study NIV has no significant effects on renal function in patients with respiratory failure. Probably these patients required low PEEP values, which were less harmful to lung parenchyma and not effective on systemic hemodynamic. Furthermore, NIV has improved endothelial function in the short term, likely by reducing oxidative stress, as improvements of the gas-analysis parameters showed. Therefore, NIV could help to reduce cardiovascular risk of patients improving endothelial function.