Methods of Anesthesia under Shock Conditions

Abstract

The use of anesthesia in patients in shock is associated with many problems and considerable risk. This is particularly true when only little time is available for adequate pretreatment because surgical intervention is urgent. In choosing a method of anesthesia for patients in shock, knowledge of the pathophysiology and treatment is of utmost importance.Le Dran first introduced the term “Shock” (French translation: “commotion”) to the medical nomenclature. The term has undergone alteration in later usage. In 1795, Latta defined shock as the condition arising from serious war injuries resulting from bullet wounds. He was the first to describe shock as “a short sojourn along the way to death.” During the First World War and the postwar period, the role of intra vascular volume deficiency in shock was clarified. Experience gained during the 1939-45 World War and the Korean War, together with the increased civilian accident rate, and research in the field of anesthesiology have led in recent years to considerble clarification of both pathogenetic and the therapeutic aspects. Today, shock can be defined as an acute reduction in tissue perfusion with consequent tissue hypoxia and metabolic acidosis, regardless of the causative factor.The organs are first functionally and then morphologically damaged. Four mechanisms can be involved in shock; 1) reduction of the volume of blood in circulation (hypovolemic shock); 2) disturbances of the vascular system (vascular shock, anaphylactic and toxic shock); 3) reduction in the functional capacity of the heart (cardiogenic shock); and 4) intrathoracic circulation impediment (shock emboli).