Non invasive proportional assist ventilation in management of severe asthma exacerbation

Background: NIV could be beneficial in selected patients with severe asthma exacerbation (SAE). However, its role is still not well defined. Objective: To evaluate the efficacy of NIV using proportional assist ventilation (PAV) in severe asthma exacerbation after failure of conventional medical therapt (CMT). Patients and Methods: Thirty patients with severe asthma exacerbation were failed to respond on conventional medical therapy. NIV was applied via face mask as a last option before intubation and mechanical ventilation. Results: The mean age was 39.2 ± 9.7 with female predominance (19 females vs. 11 males). The successful outcome was achieved in 23/30 patients (76.6%). Follow up of the mean of respiratory distress and gasometric parameters before recruitment vs. 1 h after NIV in successful group showed statistically significant improvement after NIV application as follows: HR (125.4 vs. 107.4), RR (38.2 vs. 25.4), PH (7.28 vs. 7.36), PaCO2 (55.3 vs. 42.5), PaO2 (58 vs. 87) and PEFR% Predicted (39 vs. 64) respectively (P < 0.001 for all items). Also, the same improvement was in PEFR, tidal volume, peak inspiratory pressure and triggered breaths % in successful group vs. failure group. Conclusion: NIV can relieve respiratory distress and improve gas exchange in the majority of patients with severe asthma exacerbation who are candidate for intubation after failure of conventional medical therapy