Headache, Blurred Vision, Convulsions, Loss of Consciousness or Elevated Blood Pressure

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Headache, Blurred Vision, Convulsions, Loss of
Consciousness or Elevated Blood Pressure

• Advances in Maternal and Neonatal Health

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Session Objectives

• Discuss best practices for diagnosing and
  managing hypertension, pre-eclampsia and
  eclampsia
  
• Describe strategies for controlling hypertension
• Describe strategies for preventing and treating
  convulsions in pre-eclampsia and eclampsia

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Problem

• Pregnant or recently postpartum woman who
• Has elevated blood pressure
• Complains of headache or blurred vision
• Is found unconscious or convulsing

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Elevated Blood Pressure

• Classifications
• Chronic hypertension
• Pregnancy-induced hypertension
• Pregnancy-induced hypertension without
  proteinuria
  
• Mild pre-eclampsia
• Severe pre-eclampsia
• Eclampsia

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Pre-Eclampsia

• Woman over 20 weeks gestation with
• Diastolic blood pressure 90 mm Hg AND
• Proteinuria
• Predisposes woman to develop eclampsia

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Mild Pre-eclampsia

• Two readings of diastolic blood pressure 90-110
  mm Hg 4 hours apart after 20 weeks gestation
  
• Proteinuria up to 2
• No other signs/symptoms of severe pre-eclampsia

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Severe Pre-eclampsia

• Diastolic blood pressure 110 mm Hg
• Proteinuria 3

• Other signs and symptoms sometimes present
• Epigastric tenderness
• Headache
• Visual changes
• Hyperreflexia
• Pulmonary edema
• Oliguria

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Predicting Pre-eclampsia Using Risk Factors
Study Objective and Design

• Objective To determine if risk factors for
  pre-eclampsia could be used to predict who
  develops it
  
• Design Combined retrospective and prospective
  analysis

Saudan et al 1998.
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Predicting Pre-eclampsia Using Risk Factors
Study Definitions

• Gestational hypertension was defined as the onset
  of hypertension (systolic blood pressure 140 mm
  Hg and/or diastolic blood pressure 90 mm Hg)
  after 20 weeks gestation
• Pre-eclampsia was diagnosed by standard criteria

Saudan et al 1998.
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Predicting Pre-eclampsia Using Risk Factors
Results

• No significant difference in age, parity,
  gestational age, diastolic blood pressure at
  presentation or history of diabetes.

Saudan et al 1998.
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Predicting Pre-eclampsia Using Risk Factors
Conclusion

• Those women who developed gestational
  hypertension at an earlier gestational age were
  more likely to progress to pre-eclampsia.

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Gestational Hypertension and Predicting
Pre-eclampsia Objective and Design

• Objective To determine if there is a cut off
  level of blood pressure which can be used to
  predict pre-eclampsia
  
• Design Cohort study Blood pressure was recorded
  in 1000 consecutive pregnancies at each antenatal
  visit until delivery and at the postpartum visit

Moutquin et al 1985.
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Gestational Hypertension and Predicting
Pre-eclampsia Results
Moutquin et al 1985.
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Gestational Hypertension and Predicting
Pre-eclampsia Conclusions

• Approximately 1525 of women initially diagnosed
  with gestational hypertension will develop
  pre-eclampsia
  
• It is difficult to predict who will develop
  pre-eclampsia
  

Moutquin et al 1985 Saudan 1998.
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Eclampsia

• Convulsions occurring after 20 weeks gestation in
  a woman without a previously known seizure
  disorder
  
• A small proportion of women with eclampsia have
  normal blood pressure

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Strategies for Preventing Eclampsia

• Antenatal care and recognition of hypertension
• Identification and treatment of pre-eclampsia by
  skilled attendant
  
• Timely delivery

• 3.4 of women with severe pre-eclampsia will have
  a convulsion
  
• Eclampsia is the number one cause of in-hospital
  maternal death in Nepal

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Predicting Eclampsia Study Objective and Design

• Objective Investigate potential usefulness of
  average mean arterial pressure, maximum mean
  arterial pressure and maximum diastolic pressure
  in the second trimester to predict the
  development of pre-eclampsia
• Design Retrospective analysis

Chesley and Sibai 1987.
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Predicting Eclampsia Study Results

• 207 nulliparas and 20 multiparas developed
  eclampsia
  
• Average mean arterial pressure in 2nd trimester ?
  90 mm Hg
  
• 22 of nulliparas
• 30 of multiparas
• Maximum mean arterial pressure in 2nd trimester ?
  90 mm Hg
  
• 34 nulliparas
• 35 multiparas
• Maximum diastolic pressure ? 80 mm Hg
• 8.2 nulliparas
• 30 multiparas
• Maximum diastolic pressure ?90 mm Hg
• 0 nulliparas
• 5 multiparas

Chesley and Sibai 1987.
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Predicting Eclampsia Study Conclusions

• Cannot use 2nd trimester mean arterial pressure
  or diastolic pressure to predict eclampsia
  
• Eclampsia is abrupt in onset, without warning
  signs in about 20 of women

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Initial Assessment and Management of Eclampsia

• Shout for help - mobilize personnel
• Rapidly evaluate breathing and state of
  consciousness
  
• Check airway, blood pressure and pulse
• Position on left side
• Protect from injury but do not restrain
• Start IV infusion with large bore needle
  (16-gauge)
  
• Give oxygen at 4 L/minute

DO NOT LEAVE THE WOMAN UNATTENDED
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Antihypertensive Drugs

• Hydralazine
• Labetolol
• Nifedipine

• Principles
• Initiate antihypertensives if diastolic blood
  pressure 110 mm Hg
  
• Maintain diastolic blood pressure 90-100 mm Hg to
  prevent cerebral hemorrhage

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Management During a Convulsion

• Give magnesium sulfate IM
• Gather emergency equipment (O2, mask, etc)
• Position on left side
• Protect from injury but do not restrain

DO NOT LEAVE THE WOMAN UNATTENDED
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Anticonvulsive Drugs

• Magnesium sulfate
• Diazepam
• Phenytoin

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Post-convulsion Management

• Prevent further convulsions
• Control blood pressure
• Prepare for delivery (if undelivered)

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Studies to be Reviewed

• For severe pre-eclampsia
• Magnesium sulfate vs. placebo
• For eclampsia
• Magnesium sulfate vs. diazepam
• Magnesium sulfate vs. phenytoin
• Magnesium sulfate and outcome of labor

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Magnesium Sulfate

• Use magnesium sulfate in
• Women with eclampsia
• Women with severe pre-eclampsia necessitating
  delivery
  
• Start magnesium sulfate when decision for
  delivery is made
  
• Continue therapy until 24 hours after delivery or
  the last convulsion, whichever occurs last
  

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Magnesium Sulfate vs. Placebo in Women With
Pre-Eclampsia Objective and Design

• Objective To evaluate the effectiveness of
  magnesium sulfate vs. placebo
  
• Design Double-blinded prospective randomized
  controlled trial
  
• Tertiary referral obstetrics unit in South
  Africa
  
• 822 women with severe pre-eclampsia necessitating
  delivery randomly assigned to placebo or
  magnesium sulfate
  
• Data from 699 women evaluated

Coetzee, Domisse and Anthony 1998.
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Magnesium Sulfate vs. Placebo in Women With
Pre-Eclampsia Results

• In women with severe pre-eclampsia, eclampsia
  occurred 11 times less often in women receiving
  magnesium sulfate than in women receiving placebo

Coetzee, Domisse and Anthony 1998.
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Magnesium Sulfate vs. Placebo in Women With
Pre-Eclampsia Results (continued)
RR 0.09, 95 CI (0.010.69)
Coetzee, Domisse and Anthony 1998.
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Magnesium Sulfate vs. Placebo in Women With
Pre-Eclampsia Results (continued)

• No significant difference in
• Need for antihypertensive therapy
• Number of cesarean sections performed
• Number of Live births vs. stillbirths
• Average gestational age
• Birthweight at delivery
• Number of maternal deaths

Coetzee et al 1998.
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Magnesium Sulfate vs. Diazepam for Eclampsia
Study Objective and Design

• Objective To assess effects of magnesium sulfate
  compared with diazepam when used for the care of
  women with eclampsia
  
• Design Randomized controlled trial

Duley and Henderson-Smart 2000a.
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Magnesium Sulfate vs. Diazepam Recurrence of
Convulsions
RR 0.45, 95 CI 0.35-0.58
No differences in maternal morbidity and
borderline decrease in maternal mortality
Duley and Henderson-Smart 2000a.
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Magnesium Sulfate vs. Phenytoin for Eclampsia
Study Objective and Design

• Objective To assess the effects of magnesium
  sulfate compared with phenytoin when used for the
  care of women with eclampsia
  
• Design Randomized controlled trial

Duley and Henderson-Smart 2000b.
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Magnesium Sulfate vs. Phenytoin Results

• 4 trials, 823 women
• Magnesium sulfate was associated with a reduction
  in the recurrence of convulsion when compared to
  phenytoin (RR 0.30, 95 CI 0.200.46)
  
• Magnesium sulfate was also associated with
  reduced risks of pneumonia (RR 0.66, 95 CI
  0.490.90) and intensive care unit stay (RR 0.67,
  95 CI 0.500.89)
• Magnesium sulfate reduced the need for babies
  admission to intensive care unit, reduced
  duration of stay or death in intensive care unit

Duley and Henderson-Smart 2000b.
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Magnesium Sulfate vs. Phenytoin Recurrence of
Convulsions
RR 0.30 95 CI 0.200.46
Duley and Henderson-Smart 2000b.
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Magnesium Sulfate vs. Phenytoin Pneumonia
RR 0.44 95 CI 0.240.79
Duley and Henderson-Smart 2000b.
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Magnesium Sulfate vs. Phenytoin Admission to
Neonatal Intensive Care Unit
RR 0.67 95 CI 0.500.89
Duley and Henderson-Smart 2000b.
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Magnesium Sulfate vs. Phenytoin for Eclampsia
Conclusion

• Magnesium sulfate appears to be substantially
  more effective and safer than phenytoin for
  treatment of eclampsia

Duley and Henderson-Smart 2000b.
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Magnesium Sulfate and Outcome of Labor Objective
and Design

• Objective To evaluate the outcome of labor in
  women receiving magnesium sulfate vs. phenytoin.
  
• Design 2138 women were randomly assigned to
  magnesium sulfate or phenytoin for prevention of
  eclampsia
  
• 905 nulliparous women met the inclusion
  criteria
  
• 480 women received phenytoin
• 425 women received magnesium sulfate

Leveno et al 1998.
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Magnesium Sulfate and Outcome of Labor Results
Leveno et al 1998.
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Magnesium Sulfate and Outcome of Labor Conclusion

• There is no clinical evidence that magnesium
  sulfate given for intrapartum management of
  pregnancy-induced hypertension had any effect on
  the outcome of labor

Leveno et al 1998.
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Magnesium Sulfate and Effect on Labor Objective
and Design

• Objective Evaluate effect of magnesium sulfate
  on labor
  
• Design
• Study period March 1995 to June 1996 randomized
  term mildly pre-eclamptic women to receive
  magnesium sulfate 6 g bolus then 2 g/hour or
  saline
• Cervical ripening agents/oxytocin at physicians
  discretion
  
• Women taken off protocol if developed severe
  pre-eclampsia

Witlin, Friedman and Sibai 1997.
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Magnesium Sulfate and Effect on Labor Results

• Outcome Length of labor, duration of latent and
  active phases, first and second stages
  
• Results
• No difference in duration of oxytocin magnesium
  sulfate group 14.1 hours vs. 13.5 hours
  
• Slightly higher dose of oxytocin required in
  magnesium sulfate group 13.9 mU/min vs. 11.0
  (p0.036)
  
• No significant postpartum hemorrhage or side
  effects

Witlin, Friedman and Sibai 1997.
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Magnesium Sulfate and Effect on Labor Conclusion

• Slightly higher doses of oxytocin required in
  magnesium treated groups, but no difference in
  labor and no adverse effects

Witlin, Friedman and Sibai 1997.
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Monitoring Hourly
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Monitoring Hourly
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Principles of Management

• Timing and route of delivery condition of mother
  vs. maturity of fetus
  
• Assessment of fetus evidence of fetal
  compromise
  
• Control of convulsions
• Control of hypertension
• Referral due to other organ complications
  pulmonary, renal, central nervous system
  

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Summary

• There are many manifestations of increased blood
  pressure in pregnancy
  
• It is not possible to predict which patients are
  at risk for severe pre-eclampsia or eclampsia
  
• Vigilant care is needed to make the diagnosis
• Once the diagnosis is made, appropriate treatment
  can reduce morbidity and mortality
  
• Anticonvulsants should be used, with magnesium
  sulfate being the first line
  
• Antihypertensives should be employed as needed
• Close monitoring is needed for side effects

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References

• American College of Obstetricians an
  Gynecologists. 1996. Technical Bulletin
  Hypertension in Pregnancy. 219.
  
• Chesley LC and BM Sibai. 1987. Blood pressure in
  mid-trimester and future eclampsia. Am J Obstet
  Gynecol 157(5) 12581561.
  
• Coetzee E, J Dommisse and J Anthony. 1998. A
  randomised controlled trial of intravenous
  magnesium sulphate versus placebo in the
  management of women with severe pre-eclampsia. Br
  J Obstet Gynaecol 105 300303.
• Duley L and D Henderson-Smart. 2000a. Magnesium
  sulphate versus diazepam for eclampsia (Cochrane
  Review), in The Cochrane Library, Issue 4. Update
  Software Oxford.
• Duley L and D Henderson-Smart. 2000b. Magnesium
  sulphate versus phenytoin for eclampsia (Cochrane
  Review), in The Cochrane Library, Issue 4. Update
  Software Oxford.

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References (continued)

• Leveno KJ et al. 1998. Does magnesium sulfate
  given for prevention of eclampsia affect the
  outcome of labor? Am J Obstet Gynecol 178(4)
  707712.
• Moutquin J et al. 1985. A prospective study of
  blood pressure in pregnancy Prediction of
  preeclampsia. Am J Obstet Gynecol 151 191196.
  
• Saudan P et al. 1998. Does gestational
  hypertension become pre-eclampsia? Br J Obstet
  Gynaecol 105 1177-1184.
  
• Szal SE, MS Croughan-Minihane and SJ Kilpatrick.
  1999. Effect of magnesium prophylaxis and
  preeclampsia on the duration of labor. Am J
  Obstet Gynecol 180 14751479.
• Villar MA and BM Sibai. 1989. Clinical
  significance of elevated mean arterial blood
  pressure in second trimester and threshold
  increase in systolic and diastolic blood pressure
  during third trimester. Am J Obstet Gynecol 160
  419423.
• Witlin AG, SA Friedman and BM Sibai. 1997. The
  effect of magnesium sulfate on the duration of
  labor in women with mild preeclampsia at term a
  randomized, double-blind, placebo-controlled
  trial. Am J Obstet Gynecol 176(3) 623627.