Pregnancy-induced hypertension (PIH) is one of the most common complications of pregnancy. This occurs during the 20th week of gestation or late in the second trimester of pregnancy. This is a health condition wherein there is a rise in the blood pressure and disappears after the termination of pregnancy or delivery. PIH was formerly called toxaemia or the presence of toxins in the blood. This is because its occurrence was not well understood in the clinical field. Its common manifestations are hypertension, proteinuria (presence of protein in the urine), and edema. There are 2 main types of pregnancy-induced hypertension namely: pre-eclampsia and eclampsia.
- Pre-eclampsia—this is the non-convulsive form of PIH. This affects 7% of all pregnant women. Its incidence is higher in lower socio-economic groups. It may be classified either mild or severe.
- Eclampsia—this is the convulsive form of PIH. It occurs with 5% of all pre-eclampsia cases. The mortality rate among mothers is nearly 20% and fetal mortality is also high due to premature delivery.
NORMAL ANATOMY AND PHYSIOLOGY
There are a lot of bodily changes that happen during a normal pregnancy. There are external changes that are noticeable, and there are internal changes that can only be appreciated through thorough clinical examinations. Most of the changes are the body’s response to the changes in levels of hormones and the growing demands of the fetus.
The two dominant female hormones, estrogen and progesterone, change in a normal level. Along with this, a significant rise/appearance of 4 more major hormones take place; these are 1. human chorionic gonadotropin (HCG), 2. human placental lactogen, 3. prolactin, and 4. oxytocin. All these 6 hormones interact with each other simultaneously to maintain a normal pregnancy as it progresses.
The following are the major effects of these hormones in the body:
The exact cause of pregnancy-induced hypertension is unknown; however, it is highly linked to angiotensin gene T235 and the existence of other risk factors. Malnutrition and inadequate prenatal care are the greatest risk factors. The history and presence of diabetes mellitus (DM), multifetal gestation (twin pregnancies), polyhydramnios (excessive amniotic fluid), and renal diseases are also among the major contributory factors in the development of PIH. In the past, the mystery revolving around PIH postulated a lot of theories on its true origin, most of them were believed to be of toxic nature. Among these are placental infarcts, autointoxication, uremia, pyelonephritis, and maternal sensitization to total proteins.
The incidence of PIH among pregnant women is very high (8%), costing hundreds and thousands of lives of both mothers and fetus around the world. This commonly affects first-time pregnancies due to the presence of functioning tropoblasts (develops after the 20th week of gestation and stays evident until after 48 hours after delivery. Age is also an important indicator in the development of PIH. Too early, as in teenage pregnancies and old primigravidas (first-time pregnancy) as in over 35 years of age put a woman higher chances of having pregnancy-induced hypertension.
SIGNS AND SYMPTOMS
The signs and symptoms of the type of PIH present in a pregnant woman are based on the presentation of evident clinical manifestations. These are shown in the table below:
Hypertension: Systolic- a rise of more than 30 mmHg
Diastolic- a rise of more than 15 mmHg
Proteinuria: 1 g/day
Edema: digital and periorbital
Weight gain: 2nd trimester-3 lbs/week
3rd trimester-1 lb/week
Hypertension: Systolic- a rise of more than 50 mmHg
Diastolic- a rise of more than 30 mmHg
Proteinuria: 5 g/day
Other signs and symptoms:
*Urine-oliguria (less than 400 ml/day)
-severe frontal headache
–Vision: blurred, halo, dimness, blind spot
*HELLP syndrome-hemolysis, elevated liver enzymes, and low platelet count
*all manifestations of both pre-eclampsias are magnified plus the following:
*convulsions (tonic and clonic)
*stillbirth*renal failure (oliguria and anuria)
Based on the severity of the PIH present to a person or the extent of damage left/occurred, a list of possible complications can be drawn.
- Abruption placenta
- Disseminated intravascular coagulation (DIC)
- Intrauterine growth retardation (IUGR)
- HELLP syndrome
- Maternal and/or fetal death
The changes of the mother and/or fetus to survive after an episode of convulsion or until delivery depends on the threshold on the effects of PIH and its complications. This can be:
- Good—if the symptoms are mild or those that are with mild pre-eclampsia and is responding well to the treatment regimen
- Poor—if there are multiple and long episodes of convulsions that are associated or lead to the development of persistent coma, hyperthermia, cyanosis, tachycardia, and liver damage.
- Terminal—if there is a development of one or more of the following complications:
- Congestive heart failure (CHF)
- Pulmonary edema
- Cerebral hemorrhage
- Renal failure
Diagnostic evaluations are performed after episodes of convulsions or after the client has been rushed to a health care facility. These are routinely done to assess the damages and will serve as the basis for the plan of treatment.
- 24-hour urine-protein— health problem through protein determination from the involvement of the renal system.
- Serum BUN and creatinine—to evaluate renal functioning.
- Ophthalmic examination—to assess spasm, papilledema, retinal edema/detachment, and/or hemorrhages.
- Ultrasonography with stress and non-stress test—to evaluate fetal well-being after.
- Stress test—fetalheart tone (FHT) and fetal activity are electronically monitored after oxytocin induction which causes uterine contraction.
- Non-stress test—fetal heart tone (FHT) and fetal activity are electronically monitored during fetal activity (no oxytocin induction).
- Fluid volume excess related to altered blood osmolarity and sodium/water retention.
- Altered nutrition, less than body requirements related to loss through damaged renal membrane.
- Altered tissue perfusion related to increased peripheral resistance and vasospasm in renal and cardiovascular system.
- Altered urinary elimination related to hypovolemia.
- Sensory/perceptual alterations: visual related to cerebral edema and decreased oxygenation of the brain.
- Diversional activity deficit related to decreased time for rest and sleep from stimulating environment.
- Risk for injury related to seizure episodes.
- Anxiety-related to fear of the unknown.
The overall goal of management in pregnancy-induced hypertension is directed towards the control of hypertension and the correction of developed health problems that might leadto other serious complications. Among the specially-designed treatment course for PIH are the following:
- Bed rest
- Use of antihypertensive drugs (hydralazine-drug of choice)
- Diet-high protein, high calories
- Magnesium sulphate (MgSO4) treatment
- Diazepam and amobarbital sodium (if convulsions don’t respond to MgSO4)
- Beta-adrenergic blockers (used for acute hypertension)
- Delivery (if all treatment regimen don’t work)
- Monitor blood pressure in sitting or side-lying position.
- Monitor fetal heart tone (FHT) and fetal heart rate (FHR).
- Check for deep tendon reflexes (DTR) and clonus.
- Monitor intake and output (I&O) and proteinuria.
- Monitor daily weight and edema.
- Assess for signs of labor (possibility of abruption placenta).
- Assess for emotional status.
1. Fluid balance
- Maintain patent and regulated IVF
- Strict I&O monitoring
- Monitor hematocrit level
- Vital signs monitoring every hour
- Assess breath sounds for signs of pulmonary edema
2. Tissue perfusion
- Position on left-lateral position
- Monitor fetal activity (stress and fetal activity)
3. Preventing injury
- Monitor cerebral signs and symptoms (headache, visual disturbances, and dizziness)
- Lie on left-lateral position if cerebral symptoms are present
- Secure padded side rails
- Keep oxygen suction set, tongue blade, and emergency medications (diazepam and magnesium sulphate) at all times
- Never leave an unstable patient
Discuss the health condition and planned treatment
- PIH is not lifetime
- PIH is only for the first pregnancy
- All medications and its maternal and fetal effects
Allow to ask questions and answer it truthfully
Provide emotional support to the client and family
- Reinforce the importance of rest and sleep
- Encourage family cooperation with the treatment course
- Discuss the laboratory procedures and alternative managements
- Include medical team, client, and significant others in the discussion
- Be realistic in discussing the possibilities of premature delivery
- No sign of pulmonary edema
- Adequate urine output
- No episode of seizure
- Stable and normal heart rate