02/04 Preeclampsia and Hypertension Notes

Definitions of Hypertension and Related Terms

• Hypertension:

  • Defined as a systolic blood pressure of 140 mmHg or more, or diastolic blood pressure of 90 mmHg or more.

  • Diagnosis requires measurements on two or more consecutive occasions, at least four hours apart.

• Chronic Pre-existing Hypertension:

  • Refers to hypertension confirmed before conception or diagnosed during booking (first appointment) if it occurs before 20 weeks of pregnancy.

• Gestational Hypertension:

  • New onset hypertension occurring after 20 weeks in a woman with previously normal blood pressure.

  • Blood pressure criteria are met (systolic 140 or diastolic 90) with no preeclampsia abnormalities.

  • Normal blood pressure returns within three months postpartum.

Risk Factors for Preeclampsia

• Major Risk Factors:

  • Antiphospholipid antibodies

  • Previous history of preeclampsia

  • Use of artificial reproductive technology

  • Egg donation

  • Renal disease

  • Chronic hypertension

  • Family history of preeclampsia

  • Pre-existing diabetes or previous HELLP syndrome

• Risk Assessment:

  • Women with major risk factors have approximately 20\% risk of developing preeclampsia and should be considered high risk.

  • Consultation with a specialist is advised even if no major risk factors are present.

Management and Obstetric Referral

• Initial Steps:

  • Refer any woman with major risk factors to an obstetric care provider during booking.

  • Discuss the use of aspirin for prevention and calcium supplementation as warranted.

• Lifestyle Recommendations:

  • Encourage optimal weight gain, nutrition, exercise, and stress reduction.

  • Emphasize foods that promote vascular health, such as green vegetables (e.g., broccoli and Brussels sprouts) known to increase nitric oxide.

• Diagnostic Imaging:

  • The obstetric team may perform a uterine artery Doppler scan at 20 weeks in high-risk patients with a history of severe preeclampsia or small-for-gestational-age (SGA) babies.

Preeclampsia Diagnosis

• Defined as a multisystem disorder unique to pregnancy characterized by hypertension and involvement of one or more organ systems after 20 weeks gestation.

• Diagnostic Criteria Include:

  • New hypertension after 20 weeks, and at least one of the following:

  • Proteinuria

  • Renal impairment (creatinine, oliguria)

  • Thrombocytopenia (low platelet count)

  • Elevated liver enzymes and epigastric pain

  • Neurological symptoms (headaches, visual disturbances, seizures)

  • Fetal growth restriction (SGA)

Signs and Symptoms of Preeclampsia

• Common signs include:

  • Headaches

  • Blurry vision

  • Upper abdominal pain

  • Swelling in face/hands

  • Reduced fetal movement

• Other atypical symptoms may include:

  • Neck pain, dizziness, flu-like symptoms, etc.

Investigations for Preeclampsia

• Common Laboratory Tests:

  • Serum creatinine, liver function tests, full blood count, ultrasound scan, urine protein creatinine ratio, blood pressure

• Protein Creatinine Ratio Test:

  • Measures protein levels to assess renal function. A normal range is under 30 mg per unit of creatinine; significant proteinuria may indicate impaired renal function due to endothelial damage in preeclampsia.

• Serum Creatinine:

  • Levels rising above 90 μmol/L indicate renal impairment and are concerning. Normal values generally drop during pregnancy due to increased blood volume. Elevated levels may indicate preeclampsia.

• Platelets:

  • A platelet count below 100 is a diagnostic marker for preeclampsia.

• Liver Function:

  • Elevated liver enzymes (ALT, AST) can indicate liver damage from preeclampsia.

HELLP Syndrome Overview

• Components of HELLP:

  • Hemolysis

  • Elevated Liver enzymes

  • Low Platelets

• Diagnosis: Indicated by lab findings of low platelets (< 100), elevated liver enzymes, and hemolytic anemia (red cell fragments on blood film).

• Signs and Symptoms:

  • Similar to preeclampsia with potential rapid onset and associated complications, including DIC (disseminated intravascular coagulation).

Conclusion:

• Preeclampsia and related syndromes require careful diagnostic criteria consideration and multidisciplinary coordination for proper management and outcomes. This may include discussions about prevention, intervention strategies, and monitoring of maternal-fetal health.

• Definition: HELLP syndrome is a severe form of preeclampsia characterized by a triad of symptoms: Hemolysis, Elevated Liver enzymes, and Low Platelets.

• Components of HELLP:

  • Hemolysis

  • Elevated Liver enzymes

  • Low Platelets

• Diagnosis:

  • Diagnosed when lab findings indicate low platelets (< 100), elevated liver enzymes, and hemolytic anemia (presence of red cell fragments in blood film).

• Signs and Symptoms:

  • Symptoms are similar to those of preeclampsia and can present with a rapid onset, potentially leading to complications such as DIC (disseminated intravascular coagulation).