Shock: Pathophysiology and Management

Shock is a serious clinical condition in which tissue perfusion is inadequate to meet oxygen demand, resulting in tissue hypoxia. Shock is categorized based on the primary process leading to hemodynamic instability. There are five main classifications: cardiogenic, distributive, hypovolemic, obstructive, and dissociative. Regardless of etiology, the diagnosis and initial care of patients with shock must be prompt and directed towards reversing the tissue ischemia and preventing its consequences. Often initial evaluation, diagnosis, and resuscitation occur simultaneously. The first goal is to accurately identify the etiologic cause and initiate therapy before there is irreversible damage to end vital organs. This review focuses on the pathophysiology and management of shock and addresses a number of new developments that have profoundly altered the treatment paradigms.  A number of protocols have been developed in the arena of shock resuscitation. Focused ultrasonography is recommended for the prompt recognition of complicating physiology in patients with hypotension and shock, especially in unstable patients. Tables outline classification systems for different types of shock as wel