ABSTRACT
Physiological variable Direction of change Degree/timing of change
Cardiac output ↑↑ 40%
Stroke volume ↑↑
Heart rate ↑↑ 10-20 b.p.m.
Blood pressure ↓↓ First and second trimesters
→↑ Third trimester
Central venous pressure →→
PCWP →→
SVR and PVR ↓↓ 25%–30%
Serum colloid osmotic pressure
↓↓ 10%–15%
■ Those women with cardiovascular compromise are, therefore, most at risk of pulmonary oedema during the second stage of labour and the immediate postpartum period.
