Chapter 28, Problem 1CCS

38-Year-Old Female with Preeclampsia

Ms. Johansen, 38, is 26 weeks pregnant with her first child. She was diagnosed with preeclampsia (see p. 1114) three weeks ago. Antihypertensive drugs (p. 724) and daily home care monitoring were initiated. However, her blood pressure is continuing to rise and is now 162/108 mm Hg. She complains of a constant headache, exhibits edema, and her urinalysis is positive for protein.

Her doctor has her admitted and orders further blood tests to assess Ms. Johansen's platelet level and liver function. "We may have to deliver because that’s the only cure for preeclampsia." she says to you during your clinical rotation in obstetrics. “But if we do, then the baby will have problems. It’s a tough decision because we have to balance both the mother's and the baby’s health.”

1. Although blood volume increases during pregnancy, blood pressure normally decreases. You know that blood pressure depends on cardiac output (CO) and total peripheral resistance (TPR) (Figure 19.10, p. 719). How does increased blood volume affect CO, and what factor(s) must change so that blood pressure decreases?