Physiologic changes in pregnancy and their impact on critical care

Abstract

Several organ systems manifest significant change in function during pregnancy. The cardiovascular and pulmonary systems are the two most important with regard to critical care.

Outcomes of Pregnancy in Women With Hereditary Hemorrhagic Telangiectasia

“…This is most likely the result of an increased maternal blood volume to approximately 40% and increased cardiac output during pregnancy. 11,12 In our series, patients presenting with hemothorax during pregnancy were at risk of poor neonatal outcomes (stillborn neonate, low birth weight) and need for cesarean delivery. Given the survivor bias of our study, we cannot comment on maternal death.…”

Breathing for Two

“…The net effect is that pregnancy should be considered as a hypercoagulable state. 5,10 Leukocytosis and sometimes thrombopenia may also be present. 10…”

“…Despite the increased V T , vital capacity (VC) is unchanged and total lung capacity (TLC) is reduced by less than 5% 10 (Fig. 1).…”

“…10 Only in eclampsia is the blood volume not increased. Blood volume increases by up to 2 L by the end of gestation, representing an increase of 30% to 50% above normal intravascular volume.…”

“…This is due to the decrease in functional residual capacity (FRC) caused by the elevation of the diaphragm, pushed as far as 4 cm upwards by the augmented volume of the uterus. 10,12 The FRC may fall by up to 20%, mainly at the expense of a reduction in residual volume (RV) and expiratory reserve volume (ERV). 1,5 The increase in the transverse diameter of the chest compensates for the elevation of the diaphragm, helping to maintain TLC almost unchanged.…”