The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts

A PROSPECTIVE STUDY OF CLINICAL OUTCOME AND CORRELATES FOR SUCCESS OF NONINVASIVE POSITIVE PRESSURE VENTILATION IN ACUTE RESPIRATORY FAILURE

Saumy Johnson1, Anitha Shenoy2



Background: Noninvasive ventilation (NIV) is increasingly being used in the treatment of acute respiratory failure in patients with various causes. It has fewer complications compared to invasive ventilation. The effect of NIPPV in acute respiratory failure is less clear.

Aim: To analyze the clinical outcome in patients treated with noninvasive positive pressure ventilation and to identify the determinants which predict the success and failure of this technique

Patients and methods: This prospective study included 41 patients who presented to our Multidisciplinary Intensive Care Unit (MICU) in acute respiratory failure due to various causes during the period 2006 to 2007 and considered eligible for noninvasive positive pressure ventilation (NPPV) were treated on NPPV.

Arterial blood gases, changes in chest radiograph, total duration of NIV treatment, duration of stay in the intensive care unit (ICU) and the hospital were compared. Clinical outcomes were analyzed considering each NIV treatment as successful or failure according to survival and need for endotracheal intubation.

Results: A total of 41 patients admitted during 12-month period with acute respiratory failure between the period of 2006 to 2007 were eligible for noninvasive ventilation. Noninvasive mechanical ventilation was successful in 26 (63.4%) patients with acute respiratory failure (Group I). 15 patients (36.6 %) failed NPPV (Group II), which was defined by the need for endotracheal intubation. The overall mortality was 34.1% (14 out of 41 patients).

Patients managed successfully on NIV showed a significant increase in PaO2, at 1hr and at 6hrs, their duration of ICU stay was shorter than those who failed NIV and they had significant chest x-ray changes. Changes in PaCO2, pH, and hospital stay were similar between the two groups

Conclusion: A trial of NPPV may be offered to eligible patients with acute respiratory failure An improvement in PaO2 after 1-2 h and 6 h of NPPV is associated with a successful outcome. NPPV when successful (63%) is associated with shorter ICU stay. Failure of NPPV is associated with high mortality. The effectiveness of NPPV in improving PaO2 in the initial hours could be used to predict whether the patients with acute respiratory failure could be successfully treated with NPPV and also to avoid unnecessary delay in intubation of those who deteriorate on NPPV.