Inferior Vena Cava Collapsibility Index Guide for Preoperative Fluid Therapy in Preeclampsia

This trial is studying a way to guide how much IV fluid to give before cesarean section in pregnant patients with preeclampsia (a serious condition involving high blood pressure in pregnancy). It uses an ultrasound measurement of a large blood vessel in the abdomen (the inferior vena cava) to estimate whether the patient needs more or less fluid, with the goal of reducing dangerous blood pressure drops during surgery. **You may be eligible if...** - You are critically ill with preeclampsia and are scheduled for a cesarean section **You may NOT be eligible if...** - You refuse to participate - You have severe heart disease (low ejection fraction) or a leaky heart valve (tricuspid regurgitation) - You cannot safely receive spinal anesthesia - You have severe liver or kidney problems Talk to your doctor to see if this trial is right for you.