NON-INVASIVE POSITIVE PRESSURE VENTILATION FOR MANAGEMENT OF PATIENTS WITH MODERATE TO SEVERE ACUTE EXACERBATION OF ASTHMA

Background and Objectives: Noninvasive ventilation (NIV) is increasingly used for management of acute asthma attacks but evidence supporting its optimal efficacy is scarce. This study aimed to assess the efficacy of noninvasive positive-pressure ventilation (NIPPV) in patients presenting with moderate to severe acute asthma attacks.

Materials and Methods: Thirty-four patients presenting to the emergency room of Masih Daneshvari Hospital due to asthma attack with confirmed diagnosis of asthma were randomly divided into two groups (n=17) and subjected to baseline assessments including physical examination, assessment of dyspnea by Borgscale, arterial blood gas analysis, spirometry, electrocardiography and chest X ray. After standard treatment, according to the global initiative for asthma (GINA) protocol, group 1 received NIPPV using bilevel positive airway pressure (BIPAP) for 120 minutes with inspiratory positive airway pressure (IPAP) of 12 cmH2O and expiratory positive airway pressure (EPAP) of 4 cmH2O via a facemask. Group 2 (sham) received a face mask without pressure for 120 minutes while the BIPAP was off. The afore-mentioned assessments were repeated at 1, 3, 8 and 24 hours after treatment. The results were compared between the two groups.

Results: Patients in both groups showed significant changes in heart rate, oxygen saturation rate, peak expiratory flow, forced vital capacity (FVC) and degree of dyspnea after treatment (P<0.05). In the control (sham) group, significant change also occurred in respiratory rate (P<0.05). The difference between NIPPV and sham group after treatment was significant in some parameters (P<0.05): FVC was 47% and 42% at one hour (P=0.02) and 53% and 44% at three hours (P=0.006) post-treatment in NIPPV and sham groups, respectively. FEV1/FVC predicated was 77% and 66% in NIPPV and sham groups, respectively at eight hours post-treatment (P=0.02). The arterial pH was 7.43 and 7.40 at one hour post-treatment (P=0.01). The NIPPV group showed significantly lower degree of dyspnea post-treatment compared to the sham group (P=0.01).

Conclusion: Patients who received NIV in addition to standard medical therapy for management of acute asthma exacerbation showed greater improvement in their degree of dyspnea and pulmonary function tests.