Predictors of Mortality in Patients With Advanced Lung Disease in Home Oxygen Therapy

The advanced chronic lung disease (PAD) is characterized by the development of several structural abnormalities, and pulmonary and systemic functional with low potential for reversibility, in spite of the treatment. It is defined DPA whole lung non-neoplastic chronic in its final phase. Most people with DPA consists of elderly people who have lung function and quite compromised gas exchange. These conditions determine chronically limitations in activities of daily living, negative impact on mental and social state, frequent exacerbations of the disease and numerous hospitalizations, recognized risk factors for increased morbidity and mortality (MACHADO, 2006).

Clinically, patients with APD may have one or more of the following signs and symptoms: dyspnea; cough; intolerance efforts; hypoxemia and / or hypercapnia; malnutrition and / or cachexia; anxiety and / or depression (BTS 2004).

According Garden 2004, the DPA affects millions of people worldwide and it is estimated that in Brazil there are two million individuals with APD. The most prevalent lung diseases, which in the final stage, fall under the DPA definition are classified as obstructive, restrictive, vascular and hypoventilation syndromes. Obstructive chronic respiratory insufficiency are part individuals with COPD, bronchiectasis and other bronchiolitis. Already restrictive covers patients with interticiais diseases and neuromuscular diseases. And the pulmonary vascular diseases fit patients with primary pulmonary hypertension and secondary and chronic pulmonary thromboembolism (MACHADO, 2006; PAUL, 2005).

Within the restrictive diseases with high prevalence we find the interticiais diseases are heterogeneous disorders, grouped according to clinical, radiological and functional similar. In the group of conditions that account for the majority of advanced pulmonary diseases are idiopathic pulmonary fibrosis, hypersensitivity pneumonitis and sarcoidosis. The etiology is unknown in many situations; and any known causes that stand out are the tobacco-related diseases (Guidelines interticiais lung diseases, 2012).

Vascular diseases also fits in advanced lung disease and presents significant pulmonary and systemic changes in patients. Before insulting stimuli of different nature, the pulmonary vessels undergo changes, known as pathological remodeling of the circulation. The vessel is tougher and reactive, causing pulmonary vascular diseases. Morphologic lesions in the arterial tree leads to local changes in the pattern of blood flow, that flow slowly added to the changes detected in the endothelial surface and abnormalities of the coagulation system proteins provide local thrombus formation. Pulmonary hypertension is a pathological condition that is present when the mean pulmonary artery pressure above 25 mmHg (CONSENSUS, 2009).