Introduction to the Anatomy and Physiology of Pulmonary Circulation.

In the United States, venous thromboembolism is associated with high mortality and morbidity affecting as many as 900 000 people (1-2 per 1000) each year. Estimates suggest that 60 000 to 100 000 Americans die of deep venous thrombosis/pulmonary embolism and 10% to 30% die within 1 month of diagnosis, with sudden death being the first symptom in approximately 25% of population with pulmonary embolism. One-half of the patients with deep venous thrombosis will have postthrombotic syndrome, which includes swelling, pain, discoloration, and scaling in the affected limb.

Management of Respiratory Failure.

The management of acute respiratory failure varies according to the etiology. A clear understanding of physiology of respiration and pathophysiological mechanisms of respiratory failure is mandatory for managing these patients. The extent of abnormality in arterial blood gas values is a result of the balance between the severity of disease and the degree of compensation by cardiopulmonary system.

Pathophysiology and Classification of Respiratory Failure.

Respiratory failure is a condition in which the respiratory system fails in one or both of its gas exchange functions. It is a major cause of morbidity and mortality in patients admitted to intensive care units. It is a result of either lung failure, resulting in hypoxemia, or pump failure, resulting in alveolar hypoventilation and hypercapnia.