Objective: To compare the effectiveness of pressure support ventilation and proportional assist ventilation which is two modes of non-invasive mechanical ventilation used in the treatment of chronic obstructive pulmonary disease exacerbation.
Material and Methods: Total of 20 patients was included in the study. Mean age was 63±7 years. Patients were randomized as proportional assist ventilation and pressure support ventilation groups. Non-invasive mechanical ventilation was performed using BiPAP Vision (Respironics Inc., PA) ventilator via full face mask. Initial settings were arranged as 80% support in proportional assist ventilation group and 12 cmH2O of inspiratory, 6 cmH2O of expiratory pressure in pressure support ventilation group. Arranged settings were regulated according to patient’s requirements. Patients were evaluated with arterial blood gas analysis obtained at 30th min, 1st, 2nd, 6th and 24th hour after the initiation of non-invasive mechanical ventilation, respiratory rate, visual analog scale, duration of hospitalization, requirement for intubation and mortality.
Results: Initial respiratory rate was 34±7 and initial arterial blood gas analysis parameters were as follows; pH: 7.3±0.05, PaO2: 49.3±10 mmHg, PaCO2: 68.2±11 mmHg and PaO2/FiO2: 214±33. Before and after treatment values of the parameters were not different between the groups. Visual analog scale score was higher in proportional assist ventilation group than pressure support ventilation group, not statistically significant (7.1 vs 5.7, p>0.05).
Conclusions: It is suggested that non-invasive mechanical ventilation could be performed either pressure support ventilation or proportional assist ventilation modes in the exacerbation of chronic obstructive pulmonary disease, no superiority was observed between these two modes.
Key Words: COPD Exacerbation; Non-Invasive Mechanical Ventilation; Pressure Support Ventilation; Proportional Assist Ventilation.