Objectives Describe hypertension disorder in pregnancy •Discuss complication of hypertension disorder •Administer right anesthetic management to hypertensive mother

1. Jimma University
By. Mohammednur Husen
(BSc, MSc In Anaesthesia And MBA Student)

2. Hypertensive Disorders in Pregnancy
Objectives
At the end of the class the students
will be able to
•Describe hypertension disorder in pregnancy
•Discuss complication of hypertension disorder
•Administer right anaesthetic management to
hypertensive mother

3. Patterns
1. PRE-EXISTING (CHRONIC)
HYPERTENSION
2. PRE-ECLAMPSIA
4. ECLAMPSIA
3Hypertension disorder in pregnancy

4. Pre-existing (chronic) hypertension:
– It exist before pregnancy, detected in early
pregnancy (before 20 weeks in absence of vesicular
mole) and postpartum.
– Examples:
• Essential hypertension,
• Secondary to chronic renal disorders e.g.
– Pyelonephritis and renal artery stenosis,
– Coarctation of the aorta, systemic lupus
erythematosus and pheochromocytoma.
4Hypertension disorder in pregnancy

5. • Essential hypertension: of unknown aetiology.
Glomerulonephritis.
Hydronephrosis.
Pyelonephritis.
Renal artery stenosis.
Coarctation of the aorta
Polyartheritis nodosa.
Systemic lupus erythematosus
Primary aldosteronism.
Phaeochromocytoma.
Adrenocortical tumours.
Diabetes mellitus.
Secondary to chronic renal disorder
Causes
5Hypertension disorder in pregnancy
Secondary to cardiovascular disease
Secondary to endocrine disorder

6. Predisposing factors
• Primigravidae more than multigravidae.
• Pre-existing hypertension.
• Previous pre-eclampsia.
• Family history of pre-eclampsia.
• Being over 35 years old
• It having been at least 10 years since the last pregnancy
• Hyperplacentosis i.e. excessive chorionic tissue as in
hydatidiform mole, multiple pregnancy, uncontrolled
diabetes mellitus and foetal haemolytic diseases.
• Obesity (BMI) of 35 or over
• If she has two or more of these together, then her chances
are higher.
Hypertension disorder in pregnancy 6

7. Cont…
• HTN :Blood pressure falls by the second trimester in most of
cases, but rises during the third trimester to a level some
what above that in early pregnancy.
• Deterioration of the underlying disease.
Maternal: superimposed pre-eclampsia/ eclampsia in 15-20% of
cases
Feotal:Intrauterine growth retardation and Intrauterine foetal
death.
7Hypertension disorder in pregnancy
Effect of Pregnancy on Chronic Hypertension
Effect of Chronic Hypertension on Pregnancy

8. Pregnancy-induced hypertension (PIH):
Transient hypertension:
• Late onset hypertension, without proteinuria or pathologic
oedema
Pre-eclampsia:
• Hypertension with proteinuria and / or oedema after 20
weeks of pregnancy, but may be earlier in vesicular mole.
Eclampsia:
• Pre-eclampsia + convulsions.
Superimposed pre-eclampsia or eclampsia:
• Development of pre-eclampsia or eclampsia in pre-existing
hypertension detected by a further increase of 30 mmHg
or more in systolic blood pressure or 15 mmHg or more in
diastolic blood pressure.
8Hypertension disorder in pregnancy

9. Preeclampsia
• Hypertensive disorders, which occur in
approximately 7-10% of all late pregnancies, are a
major cause of maternal mortality.
• Preeclampsia is diagnosed with the development of
hypertension with proteinuria.
• Preeclampsia–eclampsia is a disease of unknown
etiology but is unique to human pregnancy.
9Hypertension disorder in pregnancy

10. • Symptoms appear after the 20th week of
gestation, earlier than that with a hydatidiform
mole.
• The condition requires the presence of a
trophoblast but not a fetus.
• It is characterised by:
• Hypertension SBP > 140mmHg
• DBP 90mmHg
10Hypertension disorder in pregnancy

11. Severe- pre eclampsia is characterised by:
Severe hypertension
• Systolic blood pressure of 160 mm Hg
• Diastolic blood pressure of 110 mm Hg
Severe proteinuria of 5 g/24 hr
• Evidence of severe end-organ damage
– Refractory oliguria (400 mL/24 hr)
– Cerebral or visual disturbances
– Pulmonary edema or cyanosis
– Epigastric pain
– Intrauterine growth retardation
11Hypertension disorder in pregnancy

12. • Eclampsia is further complicated by
tonic/clonic convulsions which may lead to
coma in addition to those sign and symptom
of pre eclampcia
12Hypertension disorder in pregnancy

13. Cont...
• The underlying cause is not known but it is thought it
may be due to substances released from the placenta
affecting endothelial cells that cause maternal
endothelial dysfunction by one or more mechanisms.
• May result from an imbalance in placental
production of prostacyclin and Thromboxane.
• During normal pregnancy the placenta produces
equivalent quantities of these prostaglandins,
whereas in preeclamptic pregnancy, there is 7 times
more Thromboxane than prostacyclin.
13Hypertension disorder in pregnancy

14. Cont…
1. The released factors are directly toxic to
endothelial cells
2. The factors stimulate maternal oxidative
stress
3. The factors stimulate/activate inflammatory
cytokines
14Hypertension disorder in pregnancy

15. How the factors are directly toxic to
endothelial cells?
• Decreased
production of
vasodilators
(prostacyclin and
nitric oxide)
• Inactivation of
circulating nitric
oxide (vasodilator).
• Poor tissue
perfusion
to all maternal
organs
• Increases total
peripheral
resistance
resulting in
elevated blood
pressure
VASOSPASM
Gilbert & Harmon (2003) p
451-452
15
Hypertension disorder in pregnancy

16. Cont…
• In summary, maternal endothelial damage causes
vasospasm.
• Vasospasm causes:
– Leaky capillaries resulting in tissue and organ
edema
– Poor tissue perfusion to all maternal organs,
resulting in organ dysfunction
– Increased peripheral resistance resulting in
elevated blood pressure
16Hypertension disorder in pregnancy

17. Cont…
• Decreased perfusion to the kidney results in
• Decreased glomerular filtration,
• Allowing protein, mainly albumin, to be lost into
the urine.
• Oliguria develops as the disease worsens.
• Notice, the effects of vasospasm are not
confined to edema and to elevated blood
pressure…
• Thus Vasospasm is evident in other clinical
signs…
17Hypertension disorder in pregnancy

18. Arachidonic Acid
↓
Endo peroxide
↓
↓Vasoconstriction
↓Pt aggregation
↓ Uterine activity
↑Uteroplacental BF
↓
18
⇄
Prostacyclin
Hypertension disorder in pregnancy
Normal placental
production

19. Arachidonic Acid
↓
Endo peroxide
↓
↓Vasoconstriction
↓Pt aggregation
↓ Uterine activity
↑Uteroplacental BF
19
⇘
1/7x
Prostacyclin
Hypertension disorder in pregnancy

20. Sign and symptoms
• Mother with preeclampsia has,
• Placental ischemia,
• Systemic vasoconstriction,
• Increased platelet aggregation
• Oedema secondary to leaky capillaries and salt
retention
20Hypertension disorder in pregnancy

21. Cont...
• Platelet function may be impaired.
• HELLP Syndrome (Haemolysis, elevated liver
enzymes, low platelets).
• There is hyper-excitability and hyper-reflexia.
• Visual symptoms and headache suggest severe pre-
eclampsia and the possibility of an impending
convulsion (eclampsia).
• Intra-uterine growth retardation and increased
incidence of foetal distress.
21Hypertension disorder in pregnancy

22. General management
The goals of therapy in preeclampsia
– Control of hypertension
– Seizure prevention & control
– Fluid management
– Correct clotting abnormalities
– Anaesthetic management
22Hypertension disorder in pregnancy

23. Management of hypertension
– Antihypertensive therapy in preeclampsia is used to
lessen the risk of cerebral hemorrhage while
maintaining & improving, tissue perfusion.
– Plasma volume expansion combined with
vasodilation fulfills these goals
– Hydralazine and labetalol are commonly used
antihypertensive.
– Other agents include nitroglycerin, nifedipine, and
esmolol.
– Sodium nitroprusside may also be used, but only in
the short term because of a risk of cyanide toxicity in
the fetus.
23Hypertension disorder in pregnancy

24. Table.1 Comparison of Properties of Hydralazine and Labetalol
for Treatment of Hypertension
Drug Hydralazine Labetalol
Mode of action Vaso dilator α and β blockers
Speed of onset Gradual Quick
Dose 5-10mg IV slowly 10-20 mg IV slowly
Interval Repeat after 20 min Titrate to effect
Infusion rate (2-20mg)/hr (20-160 mg)/hr
Effect on heart rate Compensatory
tachycardia
No effect
24Hypertension disorder in pregnancy

25. Prevention & control of Seizure
• Magnesium sulfate is the drug of choice for
seizure control and prevention of recurrent
eclamptic seizures.
• The patient usually receives an intravenous
loading dose of 4 g in a 20% solution over 5
minutes.
• Therapeutic blood levels are maintained by
continuous infusion of 1 to 2 g/hr.
25Hypertension disorder in pregnancy

26. Cont…
• Magnesium may cause mild peripheral arterial
vasodilation.
• Magnesium ions cross the placenta readily, and
may lead to fetal and neonatal hypermagnesemia.
• In the presence of renal failure, the rate of
infusion should be modified by evaluating serum
magnesium levels.
• Magnesium has a narrow therapeutic index, with
serum levels between 2 and 3.5 mmol/L being
safe and effective.
26Hypertension disorder in pregnancy

27. Cont…
• Serum magnesium Levels should be monitored for
toxicity (respiratory depression and reduced or
absent tendon reflexes).
• If toxicity is present, 10 mL of 10% calcium
gluconate given by slow intravenous injection should
counteract its effects.
• MgSO4 potentiates the duration and intensity of
action of depolarizing and NDMRs by decreasing the
amount of Ach liberated from the motor nerve
terminals.
27Hypertension disorder in pregnancy

28. Cont…
• Diminishing the sensitivity of the end plate to
acetylcholine, and depressing the excitability of the
skeletal muscle membrane.
• Magnesium may also increase the severity of
hypotension under RA and make it more difficult to
treat.
• Judicious hydration with a balanced salt solution
may be required .
28Hypertension disorder in pregnancy

29. Cont…
• In all cases, careful monitoring of BP & UO should be
started as soon as possible.
• In severe cases, CVP monitoring may be required.
• A pulmonary artery catheter is preferred in patients
with pulmonary edema, refractory hypertension, or
oliguria.
• Monitoring should be extended to the postpartum
period.
29Hypertension disorder in pregnancy

30. Correct clotting abnormalities
– Consumption coagulopathy may require
• Infusion of fresh whole blood
• Platelet concentrates
• Fresh-frozen plasma and
• Cryoprecipitate.
– Neuraxial anesthesia is contraindicated in patients
with severe coagulopathy because of the increased
risk of an intraspinal hematoma.
30Hypertension disorder in pregnancy

31. Fluid management
• Although preeclampsia is accompanied by
exaggerated retention of water and sodium,
hypovolemia may be present because of a shift of
fluids and proteins into the extra vascular
compartment.
• There is an inverse relationship between
intravascular volume and the severity of
hypertension, patients with very elevated diastolic
pressure can be expected to have negative central
venous pressure readings.
31Hypertension disorder in pregnancy

32. Cont…
• Careful intravascular volume expansion may result in
improved maternal tissue perfusion.
• Fluid administration is accompanied by a significant
increase in pulmonary capillary wedge pressure and
cardiac index and a decrease in SVR and maternal
heart rate.
• In the presence of severe hypertension, central
venous pressure may not be an acceptable
measurement of right-sided preload.
32Hypertension disorder in pregnancy

33. Cont...
• The fluid management is guided by urine output to
maintain a urine output of 1ml/kg/hr.
• Careful IV hydration with Hartmann’s solution (or
0.9% saline) is used to maintain an adequate urine
output.
• These patients are at higher risk of developing
pulmonary oedema, therefore their fluid
management must be frequently reassessed.
33Hypertension disorder in pregnancy

34. Anaesthetic management
• Anesthetic management of a preeclamptic patient
includes a detailed preanesthetic assessment that
focuses on
– The severity of the condition
– Associated features and systemic involvement
– Evaluation of the airway
– Fluid status, and blood pressure control.
• Investigations should include
CBC, RFT and LFT.
34Hypertension disorder in pregnancy

35. Cont…
• If coagulopathy is suspected clinically, coagulation
studies should be performed.
• However, before considering neuraxial analgesia or
anesthesia, a recent P. count should be evaluated.
• DIC may require the administration of
• Whole blood, platelets
• Fresh frozen plasma and
• Cryoprecipitate.
• Initiation of neuraxial analgesia during DIC is
contraindicated.
35Hypertension disorder in pregnancy

36. Cont….
• Epidural, spinal, or CSE analgesia should no longer
be considered contraindicated, provided there is no
severe clotting abnormality or plasma volume
deficit.
• The total maternal body clearance of lidocaine may
be prolonged in preeclampsia, and repeated
administration can lead to higher blood
concentrations than in normotensive patients.
• women with severe preeclampsia appear to be at
lower risk of hypotension than normotensive
women having cesarean delivery.
36Hypertension disorder in pregnancy

37. Cont…
• Spinal anesthesia is emerging as a suitable
alternative to epidural anesthesia for cesarean
delivery in severely preeclamptic women.
• It is important to note that severely preeclamptic
women need to be adequately prepared prior to
neuraxial anesthesia with judicious hydration and
control of blood pressure.
• General anesthesia in preeclamptic patients has its
particular hazards.
37Hypertension disorder in pregnancy

38. Cont…
• Rapid-sequence induction of anesthesia and
intubation of the trachea are occasionally difficult
because of a swollen tongue, epiglottis, or pharynx.
• In p/ts with impaired coagulation, laryngoscopy
and intubation of the trachea may provoke profuse
bleeding.
• Marked systemic and pulmonary htn occurring at
intubation and extubation enhance the risk of
cerebral hemorrhage and p.edema .
38Hypertension disorder in pregnancy

39. Cont…
• However, these hemodynamic changes can be
minimized with appropriate management of HTN
• The use of ketamine and ergot alkaloids should be
avoided.
• GA may be necessary in emergencies, such as
abruptioplacenta , and in p/ts who do not meet the
criteria for neuraxial anesthesia.
39Hypertension disorder in pregnancy

40. References
1. Different website
2. Morgan and Mikhail's clinical anesthesiology
5th edition
Hypertension disorder in pregnancy 40

41. Wanci Volcanic lake
41Hypertension disorder in pregnancy