Cardiorespiratory alterations during normal pregnancy.

Maternal cardiorespiratory changes can hinder satisfactory evaluation of gravid women. Alterations in the maternal cardiorespiratory system may be further modified by pain, labor, surgery, maternal posture, and gestational age. Critical illness during pregnancy demands an aggressive multidisciplinary approach by health care professionals who are familiar with these changes. This article reviews pertinent issues that should assist physicians treating complex medical complications during pregnancy.