Target-controlled infusion of propofol for sedation in patients with non-invasive ventilation failure due to low tolerance: a preliminary study

Non-invasive ventilation (NIV) in critically ill patients is associated with a high failure rate. This prospective study assessed the feasibility and safety of target-controlled infusion (TCI) of propofol for conscious sedation during NIV in patients with NIV failure due to low tolerance. Ten patients with NIV failure due to discomfort, agitation and/or refusal to continue with this ventilatory support were included; seven had acute respiratory failure and three had acute hypercapnic respiratory failure. Patients were sedated by TCI of propofol during NIV sessions. Blood gas analysis, cardiorespiratory and ventilatory parameters, propofol concentration (Cpt) required, comfort and adverse events were recorded. Patients received a total of 85 NIV sessions, totalling 180 h of NIV under TCI of propofol (mean Cpt, 0.82 +/- A 0.25 mu g/ml). NIV under TCI of propofol significantly improved arterial blood gas analyses: mean Pa/FiO(2) ratio increased from 167 +/- A 68 pre-session to 195 +/- A 68 post-session (p < 0.05), mean PaCO(2) decreased from 57.8 +/- A 15.3 to 49 +/- A 9.8 mmHg (p < 0.05) and mean pH increased from 7.36 +/- A 0.04 to 7.4 +/- A 0.03 (p < 0.05). Three patients required endotracheal intubation, two due to evolution of underlying disease and one because of a seizure disorder. Eight patients were discharged from the intensive care unit and two died. This preliminary study shows that in a selected population, TCI of propofol can facilitate acceptance of NIV. Within the limits of a pilot study, TCI of propofol seems to be safe and effective for the treatment of NIV failure due to low tolerance.