PHYSIOLOGY AND PATHOPHYSIOLOGY OF PREGNANCY FROM THE ANESTHESIOLOGICAL - POINT-OF-VIEW

During the course of a pregnancy, a number of physiological changes take place, which increase the anaesthesia-related risks to the expectant mother Both intravascular volume and its constituent elements, cardiac output, and cardiovascular parameters undergo changes. Additional changes that are of relevance to anaesthesia are those that take place in the respiratory system. As a result of changes in the gastrointestinal tract, pregnant women must be treated as non-fasting, irrespective of when they had their last meal. As a result of the various physiological changes occurring during pregnancy, anaesthetic requirements also change. The most important patho-physiological changes that occur during pregnancy are considered to be compression of the inferior vena cava and/or the abdominal aorta, together with pre-eclamptic toxaemia that affects almost every organ system.