PURPOSE:Non-invasive positive pressure ventilation (NPPV) is increasingly used to avoid invasive mechanical ventilation (IMV) among patients with acute respiratory failure (ARF). We proposed to study the utilization of NPPV at our MICU that predominantly serves an inner city population; where smoking, obesity, COPD, Obstructive Sleep-Apnea(OSA) are very common.
METHODS:A prospective observational study was performed including all patients admitted with COPD in ARF from January 2005 to December 2007. The setting was a university affiliated closed MICU staffed 24/7 by Intensivists. Commonly used variables used to predict outcomes and co-existent morbidities like obesity, CHF, OSA were recorded by an independent observer. Outcomes of patients treated with NPPV versus IMV were compared. Data was analyzed using stepwise logistic regression and a p-value < 0.05 was considered significant.
RESULTS:Out of 266 patients admitted during this period, 110 patients were treated with NPPV while 156 with IMV (Table-1). NPPV as initial mode of ventilation was used in 41% patients with ARF. There were no significant differences in APACHE II scores (13.7 vs. 16.4, p = NS), mean admission PaCO2 values (NPPV=70.4 versus IMV=67.9, p = ns) or admission pH (NPPV=7.28 versus IMV=7.27 p = NS). There was no significant difference in mortality (NPPV=0 versus IMV=3.2 p = NS). (6)5.45 % patients on NPPV needed subsequent intubation. Younger age, obesity and OSA correlated significantly with use of NPPV (p < 0.05), while there was no correlation with CHF favoring either form of ventilatory support.
CONCLUSION:High rates of utilization of NPPV were observed in this population. Younger age, coexistent obesity and OSA strongly favored the use of NPPV, while admission PaCO2 or arterial pH did not predict the utilization of either mode.
CLINICAL IMPLICATIONS:This is one of the largest reported series on utilization of NPPV in an inner-city minority population. Failure rates with use of NPPV are much lower compared to those reported in literature. Understanding risk factors and predictors of the utilization of NPPV can enhance care of these patients.
DISCLOSURE:Sonal Rachmale, No Financial Disclosure Information; No Product/Research Disclosure Information