Flashcards in Hypertensive disorders in pregnancy Deck (70)
Describe the normal pattern of changes to blood pressure in pregnancy
Normally in pregnancy blood pressure begins to fall in the first trimester, reaches its lowest point (DBP) in the second trimester and then rises towards preconception levels by term.
What is the definition of hypertension in pregnancy?
Systolic blood pressure greater than or equal to 140 mmHg and/or Diastolic blood pressure greater than or equal to 90 mmHg as confirmed with repeated readings over several hours
a rise of more than 30/15 mmHg above pre-pregnancy baseline may be significant for some women
What is the definition of severe hypertension in pregnancy?
Systolic blood pressure greater than or equal to 160 mmHg and/or Diastolic blood pressure greater than or equal to 110 mmHg
women > 170/110 require urgent treatment to prevent complications
List 4 factors are important to ensure you take an accurate blood pressure reading?
- positioning (comfortably seated, feet resting on a flat surface not crossed, arm supported at the level of her heart, not supine)
- equipment - manual rather than automatic assessment, correctly calibrated
- correct cuff size
- rate of deflation of cuff should be less than 2mm/sec
- if questioning check on opposite arm
What is preeclampsia?
is a multisystem disorder unique to human pregnancy, characterised by hypertension (usually developing >20/40 gestation) and involvement of one or more organ systems and/or the fetus
Which 6 body systems are often involved in diagnoses of preeclampsia?
What 3 factors indicate renal involvement in diagnoses of preeclampsia?
- a spot protein/creatinine ratio (PCR) greater than or equal to 30mg/mmol showing proteinuria
- serum or plasma creatinine >90 umol/L
What factor indicates haematological involvement in diagnoses of preeclampsia?
- thrombocytopenia (low platelets)
What 2 factors indicate liver involvement in diagnoses of preeclampsia?
- raised serum transaminases
- severe epigastric and/or right upper quadrant pain
What 5 factors indicate neurological involvement in diagnoses of preeclampsia?
- convulsions (eclampsia)
- hypereflexia with sustained clonus
- visual disturbances (flashes, aura, blind spots, loss of vision)
What factor indicates cardiac involvement in diagnoses of preeclampsia?
- pulmonary oedema
What factor shows the baby is impacted in diagnoses of preeclampsia?
- intrauterine growth restriction (IUGR)
What are the most important clinical features of severe preeclampsia?
- uncontrolled blood pressure
- HELLP syndrome
- impending eclampsia
- worsening thrombocytopenia
- worsening fetal growth restriction
Which circulating angiogenic factors may be useful in diagnosing preeclampsia?
- soluble fms like tyrosine kinase-1 (sFlt1)
- soluble endoglin
-reduced placental growth factor (PlGF)
What is the earliest gestation that preeclampsia would usually present at?
20 weeks gestation
rarely presents earlier but may in women with predisposing factors like hydatidiform mole, multiple pregnancy, fetal triploidy, severe renal disease or antiphospholipid antibody syndrome.
What level of proteinuria on dipstick is considered significant and an indication that further testing is required?
++, +++ or repeated +
What are the clinical features of HELLP syndrome?
- raised Liver enzymes (transaminases)
- Low Platelets
with or without other preeclamptic features, often only two of these features is recognisable
What is the definition of fetal growth restriction and what are three factors that are often associated with it?
- where a fetus fails to achieve its growth potential in utero
- often associated with small for gestational age fetus, abnormal umbilical artery dopplers or oligohydramnios in the absence of alternate reasons for these occuring.
What is superimposed preeclampsia?
- development of preeclampsia in women with chronic (i.e. prepregnancy or
what three clinical features may be indicative of superimposed preeclampsia?
- diagnosis of superimposed preeclampsia requires the presence of oligohydramnios, abnormal umbilical artery doppler flows or other evidence of maternal system involvement.
What clinical features are unreliable as criteria for diagnosing super-imposed preeclampsia?
- worsening hypertension
- small for gestation age
- proteinuria in women for whom this was preexisting
What is gestational hypertension?
- the new onset of hypertension after 20 weeks gestation without any maternal or fetal features of preeclampsia, followed by return to normal within 3 months postpartum.
- includes some women who will go on to develop preeclampsia or chronic hypertension (continuing after 3 months postpartum)
- often associated with adverse pregnancy outcomes particularly when it develops at earlier gestations or is more severe
What is chronic hypertension?
- hypertension before pregnancy or before 20 completed weeks gestation
- may be essential, secondary to another cause or white coat
What are important secondary causes of hypertension?
- kidney disease
- systemic disease with renal involvement e.g. diabetes mellitus or lupus
- endocrine disorders
What investigations are required for a woman who presents with new onset hypertension after 20 weeks gestation?
- assess for signs/symptoms of preeclampsia (severe hypertension, headache, epigastric pain, oliguria, nausea/vomiting, concerns about fetal wellbeing)
- spot urine PCR
- full blood count
- creatinine, electrolytes, urate
- liver function tests
- ultrasound to assess fetal growth, amniotic fluid volume and umbilical artery doppler assessment
- some facilities may measure PlGF and/or sFlt1
What ongoing assessments are important for women with pregnancy induced hypertension?
- urinalysis by dipstick followed by spot urine PCR if >1+ for proteinuria
(each visit for chronic hypertension, 1-2x weekly for gestational hypertension, daily for non-proteinuric women with developing preeclampsia)
- preeclampsia bloods (FBC, Electrolytes, creatinine, LFT and coagulation studies if indicated)
(for chronic hypertension assessed if increase in BP or new proteinuria, weekly in gestational hypertension and twice weekly or more if unstable in women with signs of developing preeclampsia)
What is generally the recommendation for women who develop preeclampsia before 23-24 weeks gestation?
- high risk: high maternal morbidity and perinatal mortality
- depending on individual clinical situation, wishes of parents and institution may advise termination of pregnancy
- prolonging pregnancy means risk to mum, but improves prognosis for baby
What is key in terms of place of birth for women who develop preeclampsia between 24-36 weeks?
- tertiary hospital
- appropriate paediatric care (NICU)
What is expectant care for women with preeclampsia (usually 24-34 weeks)?
- prolong pregnancy where possible
- antenatal corticosteroids for lung maturation if possible
- magnesium sulphate for neuroprotection
- depends on maternal clinical condition, often not advisable