Is there a difference in outcome according to etiology of COPD exacerbation in patients admitted to an ICU?

Objective: The aim of our study was to detect the impact of the etiology of severe COPD exacerbations admitted to a respiratory intensive care unit (RICU). Methods: Retrospective study evaluating all episodes of severe COPD exacerbations admitted from Jan/2005 to Sept/2010 in our RICU. Patients with lung cancer were excluded. Regarding the etiology of exacerbation we divided into three groups: heart failure, respiratory infection, others/undefined. Different parameters were analyzed: APS, APACHE II, TISS, length of stay in RICU, days on invasive mechanical ventilation, mortality. In the comparative analysis, episodes with more than one cause of exacerbation were excluded. Results: Data were collected from 141 out of 184 episodes admitted to RICU. Mean age was 70±10, 76% were male. Mean APACHEII was 24.6±7.9 and mortality during the RICU admission was 30%. Comparative analysis between different etiology of severe COPD exacerbation Heart failure Respiratory infection Others/undefined p (n=29) (n=67) (n=40) Age (years) 73.2±8.7 69.6±10.6 67.2±10.1 0.0480 APS 16±6.5 14.4±6.8 15.4±9.3 0.3289 APACHE II 25.9±7.0 23.9±7.1 24.6±9.9 0.2654 TISS 22.4±5.8 23.3±5.5 21.4±7.3 0.2622 Duration of stay in RICU (days) 17.6±16.4 12±8.8 9.5±12.3 0.0041 Days on invasive mechanical ventilation 6.5±10.1 6.6±9.0 3.8±10.8 0.0151 Mortality 51.7% 28.3% 20% 0.0156 Conclusions: In our study we found higher mortality, longer duration of stay in the RICU for patients with severe COPD exacerbations caused by heart failure.