An evaluation of noninvasive mechanical ventilation application in intensive care

Aims: Noninvasive mechanical ventilation (NIMV) is a positive pressure treatment applied with a mask without the need for endotracheal intubation in patients with acute and chronic respiratory failure. C-reactive protein (CRP), procalcitonin (PCT), albumin, red blood cell distribution width (RDW), and mean platelet volume (MPV) are frequently used markers in clinical practice. Arterial blood gas (ABG) analysis is a standard method in clinical practice in intensive care, which is known to have a higher risk of complications than venous blood gas (VBG) analysis. Studies have shown a strong correlation between ABG and VBG with regard to pH, partial arterial carbon dioxide pressure (PCO2), and serum bicarbonate (HCO3). In this study, we aimed to evaluate the relationship between CRP, PCT, albumin, MPV, and RDW and in-hospital mortality and acute respiratory failure in patients undergoing NIMV. Our secondary aim was to evaluate the relationship between these parameters and VBG values. Methods: Patients with acute hypoxemic and hypercapnic respiratory failure that underwent NIMV in intensive care unit (ICU) were evaluated retrospectively. Results: The study included 99 patients with a mean age of 69.39±9.79 years. In-hospital mortality occurred in 5 (5.1%) patients. Hypercapnic respiratory failure was detected in 66 (66.7%), hypoxemic respiratory failure in 19 (19.2%), and hypoxemic + hypercapnic respiratory failure in 14 (14.1%) patients. PCT was significantly higher in patients with acute hypoxemic respiratory failure and MPV was significantly higher in patients with acute hypercapnic respiratory failure compared to other patients (p<0.05 for both). Both MPV and RDW were significantly higher in patients with in-hospital mortality (p<0.05). The baseline and 24-h PO2/FiO2 ratios were significantly lower in patients with acute hypoxemic + hypercapnic respiratory failure (p<0.05). The 24-h PO2/FiO2 ratio was significantly lower in patients with in-hospital mortality compared to patients without mortality (p<0.05). Conclusion: Both RDW and MPV should be employed in predicting mortality in patients undergoing NIMV due to acute respiratory failure. Further multicenter, prospective studies are needed to evaluate the PaO2/FiO2 ratio particularly in VBG in patients receiving NIMV due to acute respiratory failure.