Preeclampsia – Symptoms, Complications and Management

Preeclampsia is a multisystem disorder of unknown etiology characterized by the development of hypertension in pregnancy with proteinuria (protein in urine) after the 20th week in previously normotensive and proteinuric women.

Hypertension in pregnancy is defined as blood pressure above 140/90 mmHg measure 2 times with at least a 6 hr interval within 7 days. Or blood pressure above 160/110 mmHg measured even 1 time.

Proteinuria (protein in urine) defined as at least

• 300 mg protein/24 hr
• 100 mg protein /L
• 1+ on dipstick if urine specific gravity less than 1.03 or 2+ if not.

Preeclampsia accounts for 5-10% of all pregnancy. Typically it occurs after 20 weeks of gestation to 12 weeks postpartum. But if it appears before 20 weeks of gestation, suspect one of those conditions.

• Molar pregnancy
• Multiple pregnancies
• severe RH isoimmunization
• Chronic renal failure
• Antiphospholipid Ab syndrome

What are the Risk Factors of Preeclampsia?

Many risk factors make some patients prone to have preeclampsia than others. Some of these risks are

• Primigravid (first pregnancy)
• Family history of preeclampsia
• Previous history of preeclampsia
• Placental abnormality like hyperplacentosis or placental ischemia
• Obesity
• preexisting vascular disease like HTN, renal disease, collagen vascular disease, antiphospholipid syndrome, and so on.
• Diabetes, renal disease
• Age extremities < 20 and > 35
• Multiple pregnancies
• Cigarette, alcohol use
• Lack of exercise

What is the Pathophysiology of Preeclampsia?

The exact pathophysiology is not known. But there are many different theories.

Immunologic Theory

Sperm cells from the father believed to be antigen for the mother so toxin was released from the placenta to the body. That will result in an immunologic reaction and manifest as preeclampsia.
There have been researches that support this theory. A baby from a new partner/ husband has been associated with higher maternal preeclampsia prevalence.

Abnormal Placental Invasion

According to this theory, preeclampsia has 2 steps. The first step is an abnormal placental invasion and the second one is a reaction to abnormal invasion.
Normally there are 2 waves of placental development. The first wave occurs before 12 weeks of gestation. At this stage, the placenta invades the endometrial spiral artery.

The second wave occurs between 16 – 20 weeks. At this stage, the placenta invades the myometrial spiral artery. So normally, blood vessels increase its diameter which makes it lower resistance and low capacitance to accommodate increased blood flow to the fetus.
According to this theory, there is no 2nd wave in preeclampsia due to increasing thrombin and endothelin and decreased prostacyclin and nitric oxide.

Other theories

• Coagulation abnormality theory
• Abnormal angiogenesis
• Exajurated inflamation
• CVS maladaption
• Genetic predispostion
• Oxidative stress

What Impact Does Preeclampsia Has On Body Organs?

Impact On Liver – Hepatocelluallr Necrosis and Periportal Hemorrhage

If the liver is injured, the patient might have nausea, vomiting, right upper quadrant (epigastric) pain usually not respond to antiacid.
Glison capsules might be distended and rupture in 80% of cases.
It might be presented as a liver (subcapsular) hematoma. The patient will have increased liver enzymes if there is 60 – 80% of liver damage.

Impact on CVS

Preeclampsia can result in hyperdynamic ventricular function, hemoconcentration and due to vasospasm, preload will be decreased and afterload will be increased.

Impact on the Kidney

It results in glomerular endothelosis which results in protein urea.
Ischemic injury to the kidney can also happen which results in increased BUN, increased creatinine, oliguria (<500ml urine in 24 hours), or anuria (<150 ml urine in 24 hours).

Impact on the Lung

Preeclampsia results in noncardiogenic pulmonary edema on the lung because of different reasons like by causing endothelial damage, due to decreased protein in the blood, and increased hydrostatic pressure in the body.
Pulmonary edema can result in left-side heart failure.
The patients usually presented as shortness of breath in the supine position, cough, and sputum. On physical examination, we will find a bilateral fine reputation on the basal lung field.

Impact on CNS

Preeclampsia can affect CNs in two main ways.

• Ischemic and/or
• Vasogenic shock
  The ischemic attack occurs due to vasoconstriction and platelet aggregation. And vasogenic shock occurs due to edema which results in a headache that does not respond to antipain in 50 – 70% of them.
  The patient will be presented by
• severe headache,
• Visual symptoms like temporal visual loss, blurred vision, and diplopia – Due to decreased cerebral perfusion of the occipital cortex.
• Bleeding into the brain which progress to eclampsia (manifested by tonic-clonic generalized seizure)

Impact on Vascular system – Microangiopathic Hemolysis

Preeclampsia affects the vascular system as it results in leakage of fluid which causes edema.
It also increases platelet aggregation because of increased thromboxane and increased vascular damage. Platelet aggregation will result in thrombocytopenia (when platelet count <100,000).
In preeclampsia, peripheral blood vessels will be constricted and RBC hemolyzed while trying to pass through constricted vessels which are called microangiopathic hemolysis.
If there is hemolysis, we expect low hg, high LDH, high bilirubin, abnormal shaped RBC in the peripheral smear, and sometimes due to low plasma volume, hemoconcentration might be there despite hemolysis.

Classification of Preeclampsia

Depend on the severity of the symptoms we classify preeclampsia into mild and severe.

Mild preeclampsia is when blood pressure is between 140/90 and 160/110 (not included) + proteinuria. And severe preeclampsia is when either one or more of those criteria (severity features) are fulfilled.

These are: –

• BP > or = 160/110 mmHg
• Result abruption placenta, DIC
• Proteinuria > 5 gm/24 hr (> or = 3 – 4+ on dipstick)
• Oliguria
• Platelet count < 100,000/mm2
• HELLP syndrome (partial or complete)
• Cerebral or visual disturbance – headache, blurring of vision
• Severe persistent epigastric pain, severe nausea, and vomiting
• Retinal hemorrhage, exudate, or papilledema
• Intrauterine growth restriction
• Pulmonary edema – cough and shortness of breath

What are Signs & Symptoms?

Depend on the affected organ there can be different signs and symptoms. Some of them are –

• Edema on ring finger or ankle
• Headache
• Disturbed sleep
• Eye symptoms like blurred vision and vision loss due to retinal detachment, retinal infraction, vasogenic occipital edema.
• Epigastric pain, nausea, and vomiting
• Decrease urine output
• Abnormal weight gain more than >5lb / month or > 1lb per week
• yellowish discoloration of eye and skin due to increase bilirubin due to hemolysis
• Oligohydramnios
• Chronic IUGR

What Laboratory Tests Needed

• CBC – hemoglobin might be elevated due to hemoconcentration (due to plasma loss) and platelet might be < 100,000 incase of HELLP syndrome.
• Renal function test
• Liver enzyme test – AST and ALT will elevate more than 2X the normal value. ALP value is not used here because ALP will be produced by the placenta during pregnancy.
• PT, PTT – if we suspect HELLP syndrome.
• Ultrasound – Amniotic fluid volume might decrease due to placental insufficiency.
• Biophysical profile – to assess the fetus.
• Urine analysis – to check if there is a protein in the urine. To differentiate gestation hypertension with preeclampsia
• Serum LDH
• Bilirubin
• Red blood cell smear

What is the Natural Course of Preeclampsia

If the patient left untreated,

• Preeclampsia feature might remail stationary till delivery in some of the patients.
• It might progress to acute fulminating preeclampsia.
• Eclampsia may occur
• In some of the patients, spontaneously remission might occur.

What are Complications?

Preeclampsia has many complications. Some of them are –

• Hepatocellular Necrosis and Periportal Hemorrhage
• Pulmonary edema
• Eclampsia – tonic-clonic seizure in Severe preeclampsia
• Microangiopathic Hemolysis
• IUGR
• Bleeding disorder
• HELLP syndrome

What is HELLP Syndrome?

One of the severity feature in preeclamptic patients. Occur in 10-15% of complications of preeclampsia.
it is an abbreviation of 3 abnormalities.

• H stands for Hemolysis. (lab findings are LDH >600IU/L, BILIRUBIN > 1.2mg/dl)
• EL stands for Elevated liver enzyme (AST and ALT will elevate more than 2X the normal value.)
• LP stands for Low platlete (platlete < 100,000/mm3)

What is the Management of Preeclampsia

Management classified into conservative and aggressive management (termination of the pregnancy) depends on the severity of the disease.

If it is mild preeclampsia

• Deliver if GA is > 37 weeks
• if <37 weeks, follow the patient once or twice weekly with BP, urine analysis, and Ultrasound.

If it is severe preeclampsia

• Deliver if GA > 34 weeks
• Conservative management up to 34 weeks the delivery after giving steroids (dexamethasone) for 48 hours.

Medications

• magnesium sulfate to decrease seizure attack
• standing antihypertensives like methyldopa
• if bp is more than160/110, fast-acting antihypertensives like hydralazine will be given.

Terminate the pregnancy immediately if there is

• organ failure
• HELLP
• eclampsia
• abruption placenta
• nonreassuring fetal heart rate pattern
• persistent severity feature, and
• elevated hypertension even after antihypertensive and magnesium sulfate administration.

Vaginal delivery is preferable than C/s in preeclamptic patients unless there is any indication.