Presentation on hypertension in pregnancy. includes types of hypertension, management, and treatment.

1. Hypertensive in Pregnancy
Alcaraz, Adrian F.

2. Objectives
• To define the different hypertensive disorders of
pregnancy
• To identify the diagnostic criteria of these
disorders
• To briefly discuss their pathophysiology
• To determine the appropriate management of each
disorders

3. Definition of Terms

4. Hypertension
• Systolic BP ≥ 140mmHg or Diastolic BP ≥ 90mmHg
Proteinuria
• ≥ 300mg protein per 24-hour urine collection
• urine protein : creatinine ratio ≥ 0.3
• or persistent 30 mg/dL (1+ dipstick) protein in random urine
samples

5. Hypertensive Disorders of
Pregnancy

6. Chronic Hypertension
Gestational Hypertension
Preeclampsia
Eclampsia

7. Chronic Hypertension
• BP ≥ 140/90 mm Hg before pregnancy or
diagnosed before 20 weeks’ gestation not
attributable to gestational trophoblastic disease
OR
• Hypertension first diagnosed after 20 weeks’
gestation and persistent after 12 weeks
postpartum

8. Chronic Hypertension
Before Pregnancy
Pregnancy
After Pregnancy
20 weeks of
pregnancy
12 weeks after
pregnancy

9. Chronic Hypertension
Caused by:
• Essential Hypertension
• Secondary to other medical conditions (ie: renal disease)

10. Gestational Hypertension
• Hypertension for first time during pregnancy
• No proteinuria
• BP normalize before 12 weeks postpartum
• Final diagnosis made only postpartum
• May have other signs or symptoms of
preeclampsia, for example, epigastric discomfort
or thrombocytopenia

11. Gestational Hypertension
Before Pregnancy Pregnancy After Pregnancy
12 weeks after
pregnancy

12. Gestational Hypertension
Risk Factors
• maternal factors
• Primigravida (80-90% of gestational Hypertension)
• First conception with a new partner
• PMHx or FHx of gestational HTN
• DM, chronic HTN, or renal insufficiency
• Antiphospholipid syndrome
• Extremes of maternal age (<18 or >35 yr)
• fetal factors
• IUGR or oligohydramnios, multiple gestation, fetal hydrops
• Previous stillbirth or intrauterine fetal demise

13. Chronic and Gestational Hypertension
Management
• Labetalol 100-300 mg PO BID/TID; nifedipine, 30-50 mg PO
daily or α-methyldopa 250-500 mg PO TID/QID
• no ACE inhibitors, diuretics or propanolol (teratogens)

14. Preeclampsia
• BP ≥ 140/90 mm Hg after 20 weeks’ gestation
• Proteinuria ≥ 300 mg/24 hours or ≥ 1 + dipstick

15. Preeclampsia
• Increased certainty
• BP ≥ 160/110 mm Hg
• Proteinuria 2.0 g/24 hours or ≥ 2+ dipstick
• Serum creatinine ≥ 1.2 mg/dL unless known to be previously
elevated
• Platelets < 100,000/μL
• Microangiopathic hemolysis—increased LDH
• Elevated serum transaminase levels—ALT or AST
• Persistent headache or other cerebral or visual disturbance
• Persistent epigastric pain

16. Preeclampsia
Before Pregnancy
Pregnancy
After Pregnancy
20 weeks of
pregnancy
+ Proteinuria

17. Preeclampsia

18. Eclampsia
• Preeclampsia + Seizure
• Cannot be attributed to other causes in a woman
with preeclampsia
• Generalized Tonic – Clonic Seizure
• Designated as antepartum, intrapartum,
postpartum depending on the onset of convulsion
• Common on the 3rd trimester

19. Eclampsia
Before Pregnancy
Pregnancy
After Pregnancy
20 weeks of
pregnancy
+ Proteinuria
+ Seizure

20. Risk Factor

21. Incidence and Risk Factor
• Incidence: 5 - 10% (wide variation)
• Influence by
• Parity, race, ethnicity, genetic predisposition
• Nulliparous
• Total:7.6% and severe: 3.3% (Hauth, 2000)
• Risk factor
• Chronic hypertension, multifetal gestation, maternal old
age (>35 yrs), obesity, African-American ethnicity
Williams Obstetric 22 edition, Chapter 34: Hypertensive Disorders in Pregnancy

22. Incidence and Risk Factor
BMI (Kg/m2) Morbidity (%)
<19.8 4.3
>35 13.3
Gestation
twin 13
single 5
• Maternal weight and the risk of preeclampsia is progressive.
• Smoking during pregnancy reduced risk of hypertension during
pregnancy (Bainbridge,2005 ; Zhang, 1999)
• Placenta previa also reduced the risk of hypertension
Williams Obstetric 22 edition, Chapter 34: Hypertensive Disorders in Pregnancy

23. Pathogenesis

24. Pathogenesis
Abnormal Trophoblastic
Invasion
• Abnormally narrow spiral
arteriolar lumen
• Impaired placental blood flow
• Hypoxia
• Release of placental factors

25. Pathophysiology
Abnormal
Trophoblastic
Invasion

26. Pathophysiology
Abnormal Trophoblastic
Invasion
Immunological maladaptive
tolerance between maternal,
paternal (placental), and fetal
tissues
Maternal maladaptation to
cardiovascular or
inflammatory changes of
normal pregnancy
Genetic factors including
inherited predisposing
genes.

27. Pathophysiology
Inflammatory changes
• Release of cytokines (TNF-α, IL)
• ↑ ROS and free radicals
• Injury to endothelial cell

28. Pathophysiology
Endothelial Cell Activation
• Vasospasm
• Activation of Microvascular
coagulation
(Thrombocytopenia)
• ↑ Capillary Permeability

29. Pathophysiology
Preeclampsia
• Edema
• Proteinuria

30. Pathophysiology
Cardiovascular System
• Decrease cardiac output
• Decrease plasma volume
• Increase natriuretic factor
• Pulmonary edema
• Increase systemic vascular resistance
• Increase blood pressure
• Increase angiotensin II sensitivity

31. Pathophysiology
Renal System
• Proteinuria
• Decrease glomerular filtration rate →
increase creatinine
• Decrease renal blood floe
• Decrease urinary sodium, uric acid, and
calcium excretion
• Decrease plasma renin activity

32. Pathophysiology
Hemodynamic
• Decrease blood volume compare to
normal pregnancy
• Vasoconstriction and increase endothelial
permeability.
• Hemoconcentration is usually not as
marked.

33. Pathophysiology
Coagulation and platelet
• Thrombocytopenia
• Severe disease: < 100,000/uL
• Platelet count continues to decrease →
indication of delivery →the platelet count
increases progressively after delivery
(within 3 to 5 day)
• HELLP syndrome: hemolysis, elevated liver
enzymes, and low platelets

34. Pathophysiology
Liver
• Periportal hemorrhagic necrosis in
the periphery of the liver lobule
• RUQ or mid-epigastric pain and
tenderness
• Serum liver enzyme is elevated – AST
and ALT
• Hepatic hematoma (may rupture)

35. Pathophysiology
Brain
• Gross intracerebral hemorrhage –
60% (fetal in half)
• Headache, visual symptoms,
convulsions, behavioral changes

36. Predictive

37. Placental Perfusion/Vascular Resistance-
Related Tests (Provocative Pressor Tests)
“Roll-over test”
• measures the hypertensive response in women at 28 to 32 week
• resting in the left lateral decubitus position
• then “roll over” to assume a supine position
Isometric Exercise Test
• employs the same principle by squeezing a handball
Angiotensin II Infusion Test
• giving incrementally increasing doses intravenously,
• hypertensive response is quantified
sensitivities of all three tests to range from 55 to 70 percent with
specificities of approximately 85 percent

38. Placental Perfusion/Vascular Resistance-Related
Tests (Uterine Artery Doppler Velocimetry)
Doppler ultrasound in the first or mid trimester
Increased uterine artery velocimetry
Provide indirect evidence of abnormal placental
implantation

39. Renal Dysfunction-Related Tests
Serum Uric Acid
• ↓ glomerular filtration, ↑ tubular reabsorption, ↓ secretion
• reduced uric acid clearance
• ensitivity ranged from 0 to 55 percent and specificity from 77
to 95 percent

40. Endothelial Dysfunction and Oxidant
Stress-Related Tests
• Fibronectins
• Coagulation Activation
• Thrombocytopenia and platelet dysfunction
• Oxidative Stress
• Increased levels of lipid peroxides with decreased antioxidant
activity

41. Prevention

42. Dietary Manipulation
Low-Salt Diet
• Ineffective in preventing preeclampsia
Calcium Supplementation
• Low dietary calcium intake were at significantly increased risk
for gestational hypertension
• Unless women are calcium deficient, supplementation has no
salutary effects

43. Low dose Aspirin
• Suppression of platelet thromboxane synthesis
• Sparing of endothelial prostacyclin production
• Studies have shown no beneficial effect on
preeclampsia

44. Antioxidants
• Thus antioxidants have shown to be elevated on
preeclampsia
• Antioxidants have no effect

45. Management
(Preeclampsia)

46. Basic management
• Termination of Pregnancy with the least possible
trauma to mother and fetus
• Birth of an infant who subsequently thrives
• Complete restoration of health of mother

47. Prenatal Surveillance
• Until 28 weeks – prenatal every 4 weeks
• >28 weeks to 36 weeks – every 2 weeks
• > 36 weeks – every week
• For early detection of preeclampsia
• Women with hypertension are frequently admitted for
2 to 3 days to evaluate severity of new-onset
pregnancy hypertension
• Diastolic BP 81 -89 or sudden weight gain (>2lb per
week) – return visits every 2-4 days

48. Hospitalization
• For persistent or worsening hypertension or
development of proteinuria
• Evaluation:
• Detailed examination followed by daily scrutiny for clinical
findings such as headache, visual disturbance, epigastric pain,
and rapid weight gain
• Daily weight monitoring
• Analysis for proteinuria every 2 days
• BP monitoring in sitting position every 4 hours, except
between midnight and morning

49. Hospitalization
• Measurements of plasma or serum creatinine, hematocrit,
platelets and serum liver enzymes – frequency to be determined
by severity of hypertension
• Frequent evaluation of fetal size and amniotic fluid volume
• Reduce physical activity throughout much of the day
• Ample protein and calories on diet
• Sodium and fluid intake should not be limited or
forced

50. Hospitalization
• Measurements of plasma or serum creatinine, hematocrit,
platelets and serum liver enzymes – frequency to be determined
by severity of hypertension
• Frequent evaluation of fetal size and amniotic fluid volume
• Reduce physical activity throughout much of the day
• Ample protein and calories on diet
• Sodium and fluid intake should not be limited or
forced

51. Preterm Pregnancy with Preeclampsia
Glucocorticoids
• enhance lung maturation

52. Home Health Care
• Mild-to-moderate hypertension and without
proteinuria
• Reduce physical activities
• Home BP and urine protein monitoring

53. Home Health Care
• Mild-to-moderate hypertension and without
proteinuria
• Reduce physical activities
• Home BP and urine protein monitoring

54. Termination of Pregnancy
• Delivery is the cure for preeclampsia
• Headache, visual disturbance, epigastric pain or
oliguria indicate that convulsions are imminent
• Anticonvulsants are indicated for severe preeclampsia
• Moderate or severe preeclampsia that does not
improve hospitalization, delivery is advisable
• Induced by IV oxytocin
• Preinduction cervical ripening – prostaglandin or osmotic dilator
• CS indicated for more severe preeclampsia

55. Eclampsia

56. Clinical Features
• Seizures may be violent
• Typically lasting 60-75 s
• One of the signs of an impending seizure is hyperreflxia
• Symptoms that may occur before the seizure include
persistent frontal or occipital headache, blurred vision,
photophobia, right upper quadrant or epigastric pain, and
altered mental status
• Upto one third of cases, there is no proteinuria or
hypertension prior to the seizure
• After seizure usually postictal, but in some, coma may follow

57. Management (Major Component)
• Control of convulsion
• Control of hypertension
• Avoidance of diuretics unless with pulmonary
edema; limitation of IVF unless with severe blood
loss; avoidance of hyperosmotic agents
• Delivery

58. Control of convulsion
• Magnesium Sulfate as IV/IM
• Given during labor and for 24 hours postpartum
• Schedule (Continuous IV infusion):
• Loading dose: 4 to 6 g diluted in 100mL IVF over 15-20 mins
• Begin 2 g/hr in 30mL IV maintenance infusion
• Measure serum magnesium level at 4-6 hr and adjust infusion to
maintain levels between 4 and 7 mEq/L (4.8-8.4 mg/dL)
• Discontinued 24hr after delivery

59. Control of convulsion
• Schedule (Intermittent IM injections):

60. Antihypertensive Therapy
Hydralazine
• IV if SBP ≥160mmHg or DBP ≥110mmHg
• 5 to 10 mg doses at q15 to 20mins until stable (DBP: 90-100)
• More effective than labetalol
Labetalol
• IV, more rapid and associated tachycardia is minimal
• 10mg IV initially, not stable in 10mins? then 20mg is given
• Not stable in 10mins? Give 40mg

61. Antihypertensive Therapy
Hydralazine
• IV if SBP ≥160mmHg or DBP ≥110mmHg
• 5 to 10 mg doses at q15 to 20mins until stable (DBP: 90-100)
• More effective than labetalol
Labetalol
• IV, more rapid and associated tachycardia is minimal
• 10mg IV initially, not stable in 10mins? then 20mg is given
• Not stable in 10mins? Give 40mg

62. Intravenous Fluid Therapy
Lactated Ringer solution is administered routinely at
the rate of 60 to 125mL per hour unless indicated

63. Thank you