pre-eclampsia and eclampsia

see also Obstetrics

• nulliparity (3x) (but HELLP syndrome has a pre-dilection for multigravids)
• age > 40yrs (3x)
• African American race (1.5x)
• FH pregnancy-induced HT (5x)
• chronic HT (10x)
• chronic renal disease (20x)
• antiphospholipid syndrome (10x)
• diabetes (2x)
• twin gestation (4x)
• angiotensinogen gene T235 (HZ 20x, heterozygous 4x)

• HT (BP >= 140/90mmHg) present & observed before pregnancy or is Dx < 20th wk or 1st Dx during pregnancy & persists > 42nd day post-partum

• increased BP in pregnancy assoc. with proteinuria &/or generalised oedema
• NB. it is rare <20wks unless either:
  • multiple pregnancy
  • hydatidiform mole
  • foetal triploidy
  • antiphospholipid syndrome
  • severe renal disease

• as for chronic HT, with BP increase of > 30mmHg systolic, 15mmHg diastolic or 20mmHg MAP with roteinuria &/or generalised oedema

• elevated BP developing during pregnancy or in 1st 24h post-partum without signs of pre-eclampsia or chronic HT

• elevated BP:
  • sustained systolic BP >= 140mmHg or diastolic BP >= 90mmHg measured on 2 occasions >=6h apart
• AND EITHER:
  • significant proteinuria:
    • > 300mg/24h or >= 1g/ml measured on 2 separate occasions 6h apart (approx. 1+ on dipstick)
  • oedema:
    • generalised oedema or weight gain of at least 5lb in 1wk

• in addition to above criteria, any 1 of:
  • BP > 160-180mmHg systolic or > 110mmHg diastolic
  • proteinuria > 5g/24h
  • oliguria < 500ml/24h
  • cerebral or visual disturbances (eg. scotomata)
  • pulmonary oedema
  • IUGR or oligohydramnios
  • elevated serum creatinine
  • grand mal seizures (ie. eclampsia)
    • if occur > 20th wk gestation to 7 days post-partum (but reported up to 26th day puerperium)
    • assume all seizures in this period to be eclamptic until proven otherwise
    • up to 30% will not have HT, proteinuria or oedema
    • risk of eclampsia in pre-eclampsia is ~ 1 in 300
    • may be preceded by headache, blurred vision or decreased visual acuity
    • may be focal or generalised
    • usually are a single seizure lasting < 1min responding to IV MgSO4
  • any one feature of HELLP syndrome:
    • Haemolysis as manifest by microscopic features consistent with microangiopathic haemolytic anaemia on blood film (eg. presence of schistocytes)
      • NB. due to depleted intravascular volume, haematocrit may actually rise!!
    • Elevated Liver enzymes (hepatic transaminases) in absence of other causes
    • Low Platelets <100,000/mm3
    • epigastric or RUQ pain

• autoimmune thrombocytopenic purpura
• chronic renal disease
• pyelonephritis
• cholecystitis
• gastroenteritis
• hepatitis
• pancreatitis
• thrombotic thrombocytopenic purpura
• HUS
• acute fatty liver of pregnancy

• monitoring of maternal vital signs, initally every 15-30min
• place in left lateral recumbent position so that gravid uterus does not produce aortocaval compression
• ABC's:
  • oxygen if severe PET to maintain SaO2 > 90% (or > 95% if undelivered)
  • if resp. depression intubate & ventilate as indicated
• IV line & bloods for:
  • FBE, LFT, U&E, Group & hold with Ab screen
• IV fluid volume loading with 500ml:
  • prior to giving anti-hypertensives
  • prior to epidural Rx
  • if immediate delivery
  • as part of Mx of oliguria
  • NB. routine volume expansion in Rx of severe PET is NOT recommended except under certain circumstances 
    • pros:
      • volume depletion has been demonstrated in these pts
      • correction of this may improve maternal and uteroplacental circulation
      • volume expansion reduces the risk of hypotension during vasodilator Rx
    • cons:
      • risk of pulmonary oedema
      • effects are transient
      • may cause resistance to anti-hypertensives
      • not all pts are volume deplete
• strict fluid balance record
• consider CVC line if severe PET
• clean catch urine for semi-quantitative protein concentration
• if delivery not imminent, commence 24hr urine collection for protein & creatinine clearance & fluid balance charting

• if fetus is pre-viable (< 24wks) then intermittent fetal heart rate recording
• if fetus viable (> 24wks) then evaluate fetal well being & biophysical assessment:
  • ultrasound:
    • fetal number & biophysical profile (tone, movement, breathing pattens, anatomy, size, gestation, amniotic fluid volume), placental location
  • CTG monitoring:
    • continuous if severe PET ASAP
    • +/- oxytocin challenge test

• strict bed rest, quiet room

• expand maternal intravascular volume with crystalloid 500-1000ml, then,
• urgent IV hydralazine
  • 10mg slow IV boluses every 20min prn (max. 60mg)
  • NB. need to wait 10-20min for response
• if BP still high, add IV labetalol (not available in Australia as IV) 20mg stat then either:
  • 10-20mg slow IV doubling every 10-2min prn to max. 300mg, or,
  • infusion at 1-2mg/min titrated to response (decrease to 0.5mg/min or less once BP controlled) 
• NB. nitroprusside can be used for short periods but risks cyanide toxicity
• NB. GTN can be used but requires arterial line to monitor & risks metHb
• NB. ACEI's are C/I as may cause fetal anuria or renal failure

• indications:
  • eclampsia
  • severe PET with either:
    • decision to deliver baby has been made
    • hyper-reflexia with clonus
    • fundal vasospasm
    • visual disturbances
    • persistent headache
  • ??? all pts with severe PET:
    • see MJA 16 Feb 1998 Vol.(4) Mg in Rx of pre-eclampsia & eclampsia
• IV 50% magnesium sulphate:
  • from MAGPIE and Collaborative Eclampsia trials:
    • 4g load over 5min, then 1g/hr (if further seizure, give a further 2-4g IV over 5min)
    • monitor for toxicity looking for:
      • check BP, HR RR every 5min during load dose
      • loss of deep tendon reflexes (usually at 8-10mEq/L)
      • slurred speech, muscle weakness, hypotension
      • decreased resp. rate & cardiac depression (resp. then cardiac arrest usually at 13mEq/L)
      • decreased urine output
    • monitor serum levels (normal range in pregnancy 1.5-2mEq/L, Rx range 4-7mEq/L
      • if mild Mg toxicity, with-hold infusion
      • if severe Mg toxicity:
        • resp. support, O2, monitor ECG, SaO2
        • IV 10% calcium gluconate 10ml at rate`< 5ml/minute
        • consider giving loop diuretic to enhance excretion

• IV MgSO4 as above as well as Mx as for severe PET & deliver baby ASAP
• if ongoing seizures despite Rx levels of Mg, consider:
  • ensure U&E's, glucose checked
  • CT scan to exclude intracranial pathology
  • seizure Rx as for non-pregnant adults:
    • see seizures
    • diazepam (risks fetal resp. depression)
    • phenytoin 20mg/kg IV over 60min

• severe PET, deliver ASAP at any gestation
• mild PET:
  • ASAP if > 37wks (although some may wait if Cx unripe)
  • consider delivery if < 23-34wks (ie. pre-viable)
  • if 34-37wks consider amniocentesis to determine lung maturity

• if < 37wks, then:
  • admit for bed rest, or,
  • after D/W obstetric team, discharge home for bed rest with close F/U within 7 days & advised to contact hospital if:
    • headaches, scintillating scotomata or other visual changes, abdominal pain, bleeding PV, or decreased fetal movements
• if > 37wks, then admit for inducement of labor or C.S.

• admit for inducement of labor or C.S. & close monitoring & support as above, or,
• if stable & delivery not imminent, and pre-term fetus, consider transfer to tertiary obstetric centre with neonatal intensive care prior to delivery
• NB. C/I to immediate transport (ie. transfer neonate after delivery):
  • severe uncontrolled HT
  • uncontrolled eclamptic seizures
  • severe haemorrhage
  • impending delivery
  • significant fetal compromise

• Magpie Trial. Lancet 2002; 359:1877-90;
• Consensus Statement of the Aust. Soc. for the Study of HT in Pregnancy. Aust.NZ J. Obstet.Gynecol. 2000; 40:139-55;
• Pearlman, Tintinalli: Emergency Care of the Woman 1st Ed. 1998
• MJA 16 Feb 1998 Vol.(4) Mg in Rx of pre-eclampsia & eclampsia