Physiology of pregnancy: clinical anaesthetic implications

Pregnancy causes anatomical and physiological changes that have implications for the anaesthe-tist not only for intrapartum management but also when surgery is required incidentally to pregnancy. These adaptations primarily occur, so that the metabolic demands of the growing fetus may be met. Cardiovascular Physiological changes occur very early in preg-nancy, leading to an overall hyperdynamic circu-lation. These early hormonal effects lead to the primary event of peripheral vasodilatation which causes a decrease in the systemic vascular resist-ance (SVR). This occurs as early as 8 weeks of gestation.