Hypertensive disorders Flashcards
Quickly outline the normal mechanism of blood pressure control
Risk factors associated with hypertensive disorders
Gestational HTN
PE
- nulliparous
- multiple gestation
- AMA 35
- past history of HTN
- diabetes
- obesity
- family Hx of PE
- high PAPP A
Describe the pathophysiological changes which occur in women experiencing hypertension in pregnancy
Outline the classification of hypertensive disorders of pregnancy and differentiate between them
Chronic hypertension
- essential hypertension or hypertension secondary to another condition
- BP meeting HT measures before 20 weeks gestaton
- may be diagnosed before pregnancy
Gestational hypertension
- new onset of hypertension after 20 weeks gestation
- no involvement of organ systems and no fetal impact
- typically returns to normal BP by 3 months post party
Preeclampsia
- hypertension diagnosed after 20 weeks
- with the involvement of one or more organ systems or the fetus
- eg. renal, neuro, haematological, liver, pulmonary oedema, FGR
- proteinuria is common but not mandatory for diagnosis
Explain the pathophysiology behind the development of pre-eclampsia/eclampsia
PE
Abnormal placentation is main cause
- spiral artery remodelling is poor (they fail to vasodilator and lose tone)
- trophoblastic invasion is shallow, leading to a poor development of uteroplacental circulation
- this creates a high flow low resistance model - poor perfusion to placenta and foetus
Hypoperfused placenta –> proinflammatory proteins –> mothers circulation –> causes endothelial cell dysfunction = vasospasm and vasoconstriction
result = HYPERTENSION
malperfusion to other parts of body creates other signs
KIDNEY - oliguria and proteinuria
RETINA - blurred vision, flashing lights
LIVER -
Vascular injury makes them more permeable
- generalised oedema
- pulmonary oedema = cough, SOB
- cerebral oedema - headaches, confusion, SEIZURES
Eclampsia
- the development of preeclampsia to seizures
Describe the potential complications to both mother and foetus/neonate
Maternal complications
- eeclampsia
- HELLP
- placental abruption
Fetal
- hypoxia
- FGR
- stillbirth
- preterm birth
Chronic and gestational HT
- superimposed PE
Describe treatment options recommended for women experiencing hypertension in pregnancy
Medications - dose, MOA, side effects
Nifedipine 20-60mg once a day
- CCB
Labetalol 100-400mg TDS
- Beta blocker
Methyldopa - 250-750mg TDS
low dose aspirin - PE prophylaxis
Mag Sulf - prevents seizures CNS depressant
IV loading 4gm over 20 mins
maintenance 1g IV
Describe the type of testing and diagnostic criteria used to identify hypertension in pregnancy
- BP completed within a few hours of each other
- S+S assessment
- urinalysis
- LFT, Renal function test, investigation of other symptoms
Describe the signs and symptoms which may be displayed (maternal and fetal) if a woman is experiencing pre-eclampsia or eclampsia
- RUQ pain
- Blurred vision
- Headache or dizziness
- Proteinuria
- nausea and vomiting
Midwifery assessment of a woman presenting with hypertension
- Urinalysis and send urine off
- FBE
- urea, creatinine, electrolytes, LFT
- abdo palp
- reflexes and clonus
- S+S of PE
- fetal movement and CTG
- Ultrasound and dopplers
What is the minimum requirement for consultation and referral for a woman with a hypertensive disorder
What level hospital can care for these women
Midwifery management of chronic HT across the continuum
Antenatal
- consider taking first line antihypertensives
- obstetric management
- preeclampsia screen with sudden increase in Bp or new proteinuria
- Increased US for growth
- CTG if growth or movement is abnormal
Birth
- similar timing of birth and monitoring for gestational hypertension
Postnatal
Midwifery management of GHTN across the continuum
Antenatal
- continue monitoring for preeclampsia - urgent admission with any S+S
- 28-30 and 30-32 week US for growth
- medication management
- plan timing of birth indicated by blood pressure and gestation
Birth
- severe HT - continuous BP monitoring
- <160/110 - hourly BP
- consider epidural
- plan for instrumental delivery
Postnatal
- continue assessing for PE as can develop postpartum too
Midwifery management of PE across the continuum
Antenatal
- prophylactic low dose aspirin nocte
Birth - CONTROL BP
>37 weeks delivery is indicated
<37 weeks - consider mag sulf and stabilisation first, then delivery
<34 weeks - delay delivery 24-48 hours for corticosteroids, mag sulf
Postnatal
- Hourly obs (if caesar routine post-op obs as usual)
- Urine output
- Strict fluid balance - can ease off once diuresis has occurred and things settle down approx 24 hours
- 1:1 in Bs until diuresis and BP have settled
- Baby Lactates and FGR assessments
-Facilitating normal care
-Skin to skin
-BF or expressing to establish supply
Reflexes and clonus
Deep tendon reflex - tap knee tendon below knee cap on lax leg
- hyperactivity with clonus is a sign of neuromuscular irritability
Clonus - when leg is held in midwives hand and she pushes to hyperextend the foot, the foot beats under the hand
Both indicate severe PE and impending seizure
Mag sulf management
During loading dose
- 5 minutely BP, pulse and RR
- At completion of loading dose, record BP, pulse and RR, and deep tendon reflexes
- Observe for adverse effects
During maintenance dose
- Hourly BP, pulse and RR
- Hourly urine balance
- Hourly deep tendon reflexes
- Maintain accurate fluid balance (may involve catheter with burette collector) (restrict mothers fluid intake to prevent fluid overload eg. sips or ice for comfort)
Before discontinuing
- BP should be stable (consistently below 150/100)
- Adequate diuressi
- Observation of clinical improvement, with no headache or epigastric pain
