Pregnancy Induced Hypertention

Pregnancy Induced Hypertention

Pregnanncy induced hypertantion (PIH) is spasm of arterial vessels during pregnancy manifested by hypertantion, edema, and albuminuria

1. Preeclampsia

Aetiology

It remains obscure. It only occurs after 20 weeks of gestation &is uncommon before the 30 weeks.

Pathological changes

Whilst cardiac out put appears to decrease as preeclampsia worsens, generalized vasoconstriction occurs when it affects much of the physiological activity of the tissues with in the body.

Capillary permeability increases and the fluid which escapes contribute to the oedema with in the tissues. The presence of excessive fluid retention producing generalized oedema.

The uterus is also affected, particularly the vessels supplying the placental bed. Vasoconstriction and DIC reduce the uterine blood flow and vascular lesions occur in the placental bed. Placental abruption can be the result.

The liver is affected in sever cases where intracapsular hemorrhages and necrosis occur. Oedema of the liver cells produces epigastric pain and impaired liver function may result in jaundice.

The brain becomes oedematous and this, in conjuction with D/C, can produce thrombosis and necrosis of the blood vessel walls resulting in cerebrovascular accident.

The lungs become congested with fluid in severe cases oxygen is impaired and cyanosis occurs.

Diagnosis of pre eclampsia

Symptoms are rarely experienced by the mother until the disease has arrived at an advanced state. It is possible to identify the onset by the following which are known as the cardinal signs.

Blood pressure – A rise of 15-20 mmHg above the normaldiastolic pressure or an increase above 90 mmHg on two occasions.

Proteinuria in the absence of urinary tract infection isindicative of renal damage. The amount of protein in the urine is frequently taken as an index of the severity of pre eclampsia.

Oedema It may appear rather suddenly and be associatedwith a rapid rate of weight gain. Generalized oedema is significant and be classified as occult or clinical. Occult oedema may be suspected if there is a marked increase in weight. Clinical oedema may be mild or sever in nature and the severity is related to the worsening of the pre-eclampsia. The oedema pits on pressure and may be found in:

·                 Feet, ankles and pre-tibial region

·                 The hands –it may be noticed by that the mother’s rings are tight.

·                 The lower abdomen

·                 The vulva

·                 Sacral oedema

Facial oedema – may be mild resulting in puffiness of the eye lids In the presence of two of the cardinal signs a provisional diagnosis of pre eclampsia may be made. Proteinaria is considered to be the most serious manifestation.

Classification

Mild – is diagnosed when, after resting, the mother’s diastolicblood pressure rises 15-20 mmhg above the basal blood pressure recorded in early pregnancy or when the diastolic blood pressure rises above 90 mmHg. Oedema of the feet, ankles and pretibial region may be present.

Moderate – Preeclampsia is usually diagnosed when there isa marked rise in the systemic and diastolic pressure, when proteinuria is present in the absence of a urinary tract infection and when there is evidence of a more generalized edema.

Severe – Preeclampsia is diagnosed when the blood pressureexceeds 170/110mmhg, when there is an increase in the protein uria and where oedema is marked. The mother may complain of frontal head aches and visual disturbances.

Effects on the mother

·                 The condition may worsen and eclampsia may occur

·                 Placenta abruption may occur with all the complications

·                 Hematological disturbance can occur and the kidneys lungs, heart and liver may be seriously damaged.

·                 The capillaries with in the fundus of the eye may be irreparably damaged and blindness can occur.

Effects on the fetus

·                 Reduced placental function can result in low birth weight.

·                 There is an increased incidence of hypoxia in both the antenatal and intranatal periods

·                 Placental abruption, if minor, will contribute to fetal hypoxia, if major, intra uterine death will occur.

Management

Depending up on the severity of the disease a mother may be admitted to the hospital. Treatment is symptomatic because the cause of pre eclampsia is unknown.

Bed rest

Diet: As for any pregnant woman a diet rich in protein, fiberand vitamin may be recommended fluid should be encouraged.

Weight: Should be estimated and recorded twice weekly if themother is ambulant and oedema should be observed daily. Urine: should be tested for protein and ketenes.

Fluid intake and out put should be continuously measured. Blood pressure is ascertained 4- hourly in moderate preeclampsia but will be taken 2 hourly or more frequently if the mother is severely affected.

Abdominal examination will be carried out, any discomfort,tenderness or pain experienced by the mother should be recorded and reported immediately. The fetal heart rate and fetal wellbeing is also recorded. Sedation – may be prescribed

Management during labour

The nurse/midwife should remain with the mother throughout the course of labour. Preeclampsia can suddenly worsen at any time and it is essential to document the presence of oedema, the blood pressure, and urinary out put. Positioning the mother on her left side will prevent supine hypo tension.

Care of the bladder is essential and the mother should be encouraged to void urine regularly.

When the second stage commences the obstetrician and pediatrician should be notified. The latter will be present at the delivery in case the baby requires resuscitation.

Occasionally a short second stage is prescribed and in this instance the obstetrician will perform a forceps (vacuum) delivery.

Care after delivery

The blood pressure will be recorded after delivery and at least 4-hourly for 24 hours. If protein uria has been present the urine should be tested once or twice daily until it is clear and urinary out put should be recorded.

Postnatal care will be as need strict follow up especially first 24-48 hours.

Signs of impending eclampsia

The nurse must be vigilant in monitoring the maternal condition and be alert to the following signs and symptoms which signal the onset of eclampsia:

·        A sharp rise in blood pressure

·        Diminished urinary out put (oliguria)

·        Increase in protein uria

·        Head ache which is usually sever, persistent and frontal or occipital in location

·        Drowsiness or confusion

·        Visual disturbances such as blurring of vosion or flashing lights due to retinal oedema

·        Nausea and vomiting

·        Epigastric pain

The midwife/nurse who observed any one of these signs in a woman with pre-eclampsia must make a full examination in order to establish if other are present and report for urgent action.

2. Eclampsia

Eclampsia is rarely seen. Usually pregnancy induced hypertension is diagnosed and treatment is instituted in order to prevent eclampsia. The incidence of eclampsia is approximately 1 in 1500 pregnancies and of these about 20% occurs in the antenatal period, 25% occur intrapartum and 35% with in the first few hours after delivery. Eclampsia is characterized by convulsions and coma.

The stages of an eclamptic fit 

Premonitory stage (lasts 10-20 seconds)

The mother is restless and rapid eye movements can be noted.

·                 The head may be drawn to one side and twitching of the facial muscles may occur

·                 The mother has no perception of the impending fit and shows altered awareness.

Tonic stage (lasts 10-20 seconds)

·                 The muscles of the mother’s body go into spasm and become rigid and her back may become arched.

·                 Her teeth will become tightly clenched and her eyes staring

The clonic stage (lasts 60-90 seconds)

·                 Violent contraction and intermittent relaxation of the mother’s muscles produces conversions movements

·                 Salivation increases and foaming at the mouth occurs.

·                 The mother’s face becomes congested and bloated and the features become distorted.

·                 She is unconscious, her breathing detorous and her pulse full and bounding. -Gradually the convulsion subsides.

Stage of coma

·                 Stertorous breathing continues and coma may persist for minutes or hours.

·                 Further convulsions may occur before the mother regains consciousness.

Emergency Care of a mother with eclampsia

·                 Clear and maintain the mother’s air way (suction)

·                 Administer oxygen and prevent severe hypoxia

·                 Prevent the mother from being insured during the clonic stage.

·                 Monitor vital signs

Treatment may be given as follows:

Intravenous therapy will be commenced to maintain adequate hydration. The regimen will be prescribed according to the mother’s needs and ketoacidosis must be prevented. Dextrose 5% will be used for intravenous drug administration.

·                 Sedatives to control convulsion

Where the hypertension is sever and requires rapid reduction, intravenous hydrallazine may be given.

·                 The volume of urine and the albumin uria need to be monitored.

·                 Monitor intake and output

·                 Avoid disturbance (noise, light, etc)

·                 Keep emergency drugs ready

N.B. General management of eclampsia

·                 control convulsion

·                 Control blood pressure

·                 Deliver the baby

Complications of eclampsia

·                 Cerebral: hemorrhage, thrombosis and mental confusion

·                 Renal: acute renal failure

·                 Hepatic: liver necrosis

·                 Cardiac; myocardial failure

·                 Respiratory: asphyxia, pulmonary oedama, broncho-pneumonia

·                 Visual: temporary blindness

·                 Injuries: bitten tongue, fractures

·                 Fetal: hypoxia and still birth