A condition in pregnancy characterised by abrupt hypertension (a sharp rise in blood pressure), Proteinurea (leakage of large amounts of the protein into the urine) and edema (swelling) of the hands, feet, and face.

Preeclampsia is the most common complication of pregnancy. It affects about 5% of pregnancies. It occurs in the third trimester (the last third) of pregnancy.

The hypertension component of the disease is present when the systolic blood pressure is greater than 140 mm Hg or the diastolic blood pressure is greater than 90 mm Hg in a woman known to be normotensive prior to pregnancy. The diagnosis requires 2 such abnormal blood pressure measurements recorded at least 6 hours apart.

Proteinuria is present when the urinary protein concentration is greater than 300 mg during a 24-hour period. The 24-hour urine collection is the definitive test to diagnose proteinuria; however, if it is not available, then a concentration of at least 30 mg/dL (at least 1+ on dipstick testing) in at least 2 random urine samples collected at least 6 hours apart may be used.

Preeclampsia can be classified as mild or severe. Severe preeclampsia is characterized by

(1) a systolic blood pressure greater than 160 mm Hg or diastolic blood pressure greater than 110 mm Hg on 2 occasions at least 6 hours apart in a woman on bed rest and

(2) the presence of significant proteinuria.

Marked proteinuria is defined as 5 g or more of protein in a 24-hour urine collection.

Severe preeclampsia, at times, may be associated with oliguria, cerebral or visual disturbances, pulmonary edema or Cyanosis, epigastric or right upper quadrant abdominal pain, impaired liver function, thrombocytopenia, or intrauterine growth restriction.

In mild preeclampsia, hypertension and proteinuria are present, but not to these extreme levels, and the patient has no evidence of other organ dysfunction.

History:

• Seizures, coma, headache, focal neurologic symptoms, and visual disturbances in pregnant women can be evidence of the development of preeclampsia or a suggestion of cerebral hemorrhage, edema, vasospasm, or thrombosis.

• Clients report decreased urine output and abdominal pain.

Physical:

• Asymptomatic hypertension is discovered during the routine prenatal examination.

• Diffuse oedema has a high specificity for preeclampsia.

• Neurologic findings such as papilledema and hyperreflexia must be addressed quickly because they can herald the onset of eclampsia.

• Petechiae and bruising can suggest coagulopathy.

• Right upper quadrant or midepigastric tenderness (chest pain) develops as a result of hepatocellular necrosis.

Causes:

The exact cause of preeclampsia has not been elucidated. Current research uses the known risk factors to help develop theories about the exact etiology of preeclampsia.

• Four times the relative risk - Being the daughter or sister of a woman who has had preeclampsia

• Three times the relative risk - Young maternal age

• • Nulliparity: Of preeclampsia cases, 85% occur in primigravid women.

• • Twin pregnancies

• As high as twice the relative risk

• • Multiparity and conception with a new partner

• • Black race (there is evidence to suggest black women are twice as likley to develop preeclampsia than white women)

• Additional risk factors

• • Diabetes: Women with Gestational Diabetes have a 15% increased risk; women with pregestational diabetes have a 30% risk of preeclampsia.

• • Hypertension

• • Renal disease

• Decreased risk - Smoking

Treatment

Medical Care

The only definitive treatment for preeclampsia is delivery of the fetus and placenta. This is a reasonable choice for viable fetuses or in cases in which the mother's health is at significant risk. Examples of significant health risk include eclampsia, pulmonary oedema, compromised renal function, abruptio placentae, platelet count less than 100,000/mL, a ratio of serum alanine aminotransferase to serum aspartate aminotransferase that is twice the reference range with concomitant epigastric and right upper quadrant tenderness, persistent severe headache or visual changes, and uncontrolled severe hypertension. In these cases, glucocorticoids can be administered to women with preterm pregnancies, with delivery postponed for 48 hours to allow the steroids to improve fetal lung maturity.

However, preeclampsia often can be treated in women with preterm pregnancies if symptoms are mild to moderate. Examples of this type of preeclampsia include proteinuria of any amount, oliguria (<0.5 mL/kg/h) that resolves with fluid intake, an alanine aminotransferase/aspartate aminotransferase ratio higher than twice the reference range, no abdominal tenderness, and controlled hypertension. In patients with controlled hypertension, the treatment is to lower blood pressure.

Medical management focuses on antihypertensive treatment and anticonvulsant prophylaxis.

In summary, a client with severe preeclampsia must be admitted to the hospital. The disposition of the preterm patient with mild preeclampsia is less certain. These clients have traditionally been admitted and placed on bed rest for the duration of the pregnancy. Recent studies have suggested that most of these clients can be safely treated at home or in a day-unit as long as frequent maternal and fetal evaluation can be performed.

Surgical Care

Failure of medical management necessitates iatrogenic vaginal delivery. Maternal or fetal deterioration requires emergent caesarian delivery.

Consultations

An obstetrician must be consulted regarding the initial treatment of a woman with preeclampsia. The specialist's familiarity with the complications of pregnancy and their treatment makes him or her uniquely suited to make decisions regarding antihypertensive and anticonvulsant therapies. Additionally, obstetricians can best weigh the risks and benefits of continuing a preterm pregnancy.

References

http://www.medterms.com/script/main/art.asp?articlekey=11892

http://www.emedicine.com/med/topic1905.htm#section~workup