1. Hypertension in Pregnancy

2. OBJECTIVES List criteria for the diagnosis of preeclampsia
List criteria for the diagnosis of severe preeclampsia/HELLP syndrome
Discuss current management considerations

3. Hypertension Sustained BP elevation of 140/90 or greater
Proper cuff size
Measurement taken while seated
Use 5th Korotkoff sound

4. Forms of HTN in Pregnancy
Gestational Hypertension
Formerly called Pregnancy-Induced Hypertension
No proteinuria

5. Forms of HTN in Pregnancy
Gestational Hypertension
Preeclampsia
Hypertension with proteinuria
May have other evidence of end-organ disease
Edema
Visual changes
Headache
Epigastric pain
Laboratory changes

6. Older Criteria for Gestational HTN
30/15 increase in BP over baseline levels
No longer appropriate
73% of patients will exceed 30 mm systolic and 57% will exceed 20 mm diastolic

7. Patient Categories
25%

8. Forms of HTN in Pregnancy
Gestational Hypertension
Preeclampsia
Chronic Hypertension
As a group these occur in 12 to 22% of pregnant patients and are directly responsible for approximately 18% of maternal mortality nationally.

9. Chronic Hypertension Pre-existing hypertension
Hypertension before 20 weeks in the absence of gestation
If hypertension persists beyond 6 weeks postpartum

10. Preeclampsia Hypertension after 20 weeks of gestation
Proteinuria- 300mg
Edema

11. Preeclampsia Hypertension after 20 weeks of gestation
Proteinuria- 300mg
Edema
BP > 160 systolic or >110 diastolic
5grams of protein in 24 hour urine
Oliguria
Cerebral of visual distrubances
Pulmonary edema or cyanosis
Epigastric or RUQ pain
Impaired liver function
Thrombocytopenia
IUGR

12. Risk Factors FACTOR RISK RATIO Nulliparity 3:1 Age > 40
African American
1.5:1
Chronic hypertension
10:1
Renal disease
20:1
Antiphospholipid syndrome

13. Risk Factors FACTOR RISK RATIO Family history of PIH 5:1
Diabetes mellitus
2:1
Twin gestation
4:1

14. Prevention Low dose ASA ineffective in patients at low risk
Calcium supplementation is ineffective (2.0 g of calcium gluconate per day)
No compelling evidence that either are harmful
Recent study done with antioxidant (1,000mg VitC and 400mg VitE).
Small study that needs to be confirmed.

15. Cardiovascular Effects
Hypertension
Increased cardiac output
Increased systemic vascular resistance
Hypovolemia

16. Neurologic Effects Seizures-eclampsia Headache Cerebral edema
Hyper-reflexia

17. Pulmonary Effects Capillary leak Reduced colloid osmotic pressure
Pulmonary edema

18. Hematologic Effects Volume contraction Elevated hematocrit
Low platelets
Anemia due to hemolysis

19. Renal Effects Decreased glomerular filtration rate
Increased BUN/creatinine
Proteinuria
Oliguria
Acute tubular necrosis

20. Fetal Effects Increased perinatal morbidity Placental abruption
Fetal growth restriction
Oligohydramnios
Fetal distress

21. Severe Preeclampsia BP > 160-180 systolic or 110 diastolic
Proteinuria > 5 g per day
Pulmonary edema
Oliguria
Elevated liver enzymes
Low platelets
Growth restriction
Decreased AFV
Headache
Epigastric pain

22. Management The ultimate cure is delivery Assess gestational age
Assess cervix
Fetal well-being
Laboratory assessment
Rule out severe disease!!

23. Gestational HTN at Term
Delivery is always a reasonable option if term
If cervix is unfavorable and maternal disease is mild, expectant management with close observation is possible

24. Mild Gestational HTN not at Term
Rule out severe disease
Conservative management
Serial labs
Twice weekly visits
Antenatal fetal surveillance
Outpatient versus inpatient

25. Indications for Delivery
Worsening BP
Nonreassuring fetal condition
Development of severe PIH
Fetal lung maturity
Favorable cervix

26. Unfavorable Cervix No contraindication to prostaglandin agents
If < 32 weeks, consider cesarean
When favorable, oxytocin

27. Hypertensive Emergencies
Fetal monitoring
IV access
IV hydration
The reason to treat is maternal, not fetal
May require ICU

28. Criteria for Treatment
Diastolic BP >
Systolic BP > 200
Avoid rapid reduction in BP
Do not attempt to normalize BP
Goal is DBP < 105 not < 90
May precipitate fetal distress

29. Characteristics of Severe HTN
Crises are associated with hypovolemia
Clinical assessment of hydration is inaccurate
Unprotected vascular beds are at risk, eg, uterine

30. Key Steps Using Vasodilators
cc of fluid, IV
Avoid multiple doses in rapid succession
Allow time for drug to work
Avoid over treatment

31. Acute Medical Therapy Hydralazine Labetalol Nifedipine Nitroprusside
Diazoxide
Clonidine

32. Hydralazine Dose: 5-10 mg every 20 minutes Onset: 10-20 minutes
Duration: 3-8 hours
Side effects: headache, flushing, tachycardia, lupus like symptoms
Mechanism: peripheral vasodilator

33. Labetalol
Dose: 20mg, then 40, then 80 every 20 minutes, for a total of 220mg
Onset: 1-2 minutes
Duration: 6-16 hours
Side effects: hypotension
Mechanism: Alpha and Beta block

34. Nifedipine Dose: 10 mg po, not sublingual Onset: 5-10 minutes
Duration: 4-8 hours
Side effects: chest pain, headache, tachycardia
Mechanism: CA channel block

35. Clonidine Dose: 1 mg po Onset: 10-20 minutes Duration: 4-6 hours
Side effects: unpredictable, avoid rapid withdrawal
Mechanism: Alpha agonist, works centrally

36. Nitroprusside Dose: 0.2 – 0.8 mg/min IV Onset: 1-2 minutes
Duration: 3-5 minutes
Side effects: cyanide accumulation, hypotension
Mechanism: direct vasodilator

37. Seizure Prophylaxis Magnesium sulfate 4-6 g bolus 1-2 g/hour
Monitor urine output and DTR’s
With renal dysfunction, may require a lower dose

38. Magnesium Sulfate Is not a hypotensive agent
Works as a centrally acting anticonvulsant
Also blocks neuromuscular conduction
Serum levels: 6-8 mg/dL

39. Toxicity Respiratory rate < 12 DTR’s not detectable
Altered sensorium
Urine output < cc/hour
Antidote: 10 ml of 10% solution of calcium gluconate 1 v over 3 minutes

40. Treatment of Eclampsia
Few people die of seizures
Protect patient
Avoid insertion of airways and padded tongue blades
IV access
MGSO4 4-6 bolus, if not effective, give another 2 g

41. THE FIRST THING TO DO AT A SEIZURE IS TO TAKE YOUR OWN PULSE!

42. Alternate Anticonvulsants
Diazepam 5-10 mg IV
Sodium Amytal 100 mg IV
Pentobarbital 125 mg IV
Dilantin mg IV infusion

43. After the Seizure Assess maternal labs Fetal well-being
Effect delivery
Transport when indicated
No need for immediate cesarean delivery

44. Other Complications Pulmonary edema Oliguria Persistent hypertension
DIC

45. Pulmonary Edema Fluid overload Reduced colloid osmotic pressure
Occurs more commonly following delivery as colloid oncotic pressure drops further and fluid is mobilized

46. Treatment of Pulmonary Edema
Avoid over-hydration
Restrict fluids
Lasix mg IV
Usually no need for albumin or Hetastarch (Hespan)

47. Oliguria 25-30 cc per hour is acceptable
If less, small fluid boluses of cc as needed
Lasix is not necessary
Postpartum diuresis is common
Persistent oliguria almost never requires a PA cath

48. Persistent Hypertension
BP may remain elevated for several days
Diastolic BP less than 100 do not require treatment
By definition, preeclampsia resolves by 6 weeks

49. Disseminated Intravascular Coagulopathy
Rarely occurs without abruption
Low platelets is not DIC
Requires replacement blood products and delivery

50. Anesthesia Issues
Continuous lumbar epidural is preferred if platelets normal
Need adequate pre-hydration of 1000 cc
Level should always be advanced slowly to avoid low BP
Avoid spinal with severe disease

51. HELLP Syndrome
He-hemolysis
EL-elevated liver enzymes
LP-low platelets

52. HELLP Syndrome Is a variant of severe preeclampsia
Platelets < 100,000
LFT’s x normal
May occur against a background of what appears to be mild disease

53. Conservative Management
Controversial
Steroids
Requires tertiary care
Must have stable labs and reassuring fetal status
May use antihypertensives

54. SUMMARY Criteria for diagnosis Laboratory and fetal assessment
Magnesium sulfate seizure prophylaxis
Timing and place of delivery