Pregnancy Induced Hypertension (PIH) and Preeclampsia
A. Discussion of disease/condition
Pregnancy Induced Hypertension (PIH) is a multi-organ disease process that develops as a result of pregnancy and regresses in the postpartum period. It usually develops after 20 weeks of gestation in a woman who had normal blood pressure. It is defined as an elevation of systolic and diastolic pressures equal to or above 140/90 mm Hg. In clinical practice, the terms PIH and preeclampsia are used interchangeable, but in preeclampsia the woman also has protein in her urine indicating that there is renal involvement as well. The only know cure for preeclampsia is delivery of the fetus. It is a relatively common problem of pregnancy and affects about 8% of all pregnancies. (Murray, p680)
2. Risk factors
There are many factors that increase a woman's risk. Those include women who are having their first baby, those under 17 years old, women who are obese, having diabetes mellitus, chronic hypertension, or preexisting vascular disease and women with multi-fetal gestation. Also a woman is more likely to have preeclampsia if the mother or sister has the disorder. (Murray, p681)
3. Etiology and Pathophysiology
Preeclampsia is due to generalized vasospasm. In natural pregnancy, vascular volume and cardiac output increase significantly, but despite these increases, blood pressure does not rise in normal pregnancy. This is because pregnant women resistance to the effects of vasoconstrictors such as angiotension. However, in preeclampsia, peripheral vascular resistance increase because some women are sensitive to angiotension
Vasospasm decrease the diameter of blood vessels which results in endothelia cell damage, impeded blood flow and elevated blood pressure. As a result of this circulation to all body organs, including the kidneys, liver, brain and placenta, is decreased. This will cause many changes such as decreased venal perfusion, glomerular damage, impaired liver function, small cerebral hemorrhages, pulmonary edema, dyspnea and decreased placental circulation. Decrease placental circulation can result in infarctions that increase the risk for abruptio placentae. Also when maternal blood flows through the placenta is decreased, the fetus is likely to experience intrauterine growth restriction and persistent fetal hypoxemia and acidosis (Murray, p679-681)
4. Signs and Symptoms
Hypertension, generalized edema and proteinuria are the three classic signs of preeclampsia. The first sign is that a pregnant women may notice is edema and a rapid weight gain which are due to fluid retention.
Hypertension is defined as sustained blood pressure equal to or above 140/90. Blood pressure should be taken in the sitting position with the arm supported in a horizontal position at hear level.
Proteinuria usually develops later than hypertension an edema. The combination of proteinuria and hypertension...