Physiopathology of shock

Area of Science:

• Cardiovascular Medicine
• Critical Care Medicine
• Pathophysiology

Background:

• Shock syndromes represent a critical state of circulatory dysfunction.
• Understanding the distinct pathophysiological mechanisms of different shock types is crucial for effective management.
• Existing classifications differentiate shock based on primary etiological factors.

Purpose of the Study:

• To delineate the specific initial macro-hemodynamic derangements characterizing cardiogenic, hemorrhagic, and inflammatory shock.
• To highlight the primary site of circulatory insult in each shock subtype.

Main Methods:

• Review of established physiological principles of shock.
• Analysis of macro-hemodynamic variables affected in each shock type.
• Distinguishing between primary microcirculatory and macrocirculatory derangements.

Main Results:

• Hemorrhagic shock is characterized by initial derangements in blood volume and venous return.
• Cardiogenic shock presents with primary pump failure, affecting cardiac output and mean arterial pressure.
• Inflammatory shock primarily impacts the microcirculation, with systemic inflammatory response affecting total peripheral resistance.

Conclusions:

• Shock syndromes exhibit distinct initial hemodynamic profiles.
• Differentiating shock types based on primary affected variables aids in understanding their pathophysiology.
• Inflammatory shock uniquely involves initial microcirculatory compromise alongside macrocirculatory changes.