Severe pre-eclampsia. - PowerPoint PPT Presentation

Loading...

PPT – Severe pre-eclampsia. PowerPoint presentation | free to download - id: 6bc790-YzdhY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Severe pre-eclampsia.

Description:

Severe pre-eclampsia. Tom Archer, MD, MBA Director, OB Anesthesia UCSD Hillcrest March 28, 2012 * * Pre-eclampsia complication: pulmonary edema Fluid overload ... – PowerPoint PPT presentation

Number of Views:33
Avg rating:3.0/5.0
Slides: 66
Provided by: Tom1193
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Severe pre-eclampsia.


1
Severe pre-eclampsia.
  • Tom Archer, MD, MBA
  • Director, OB Anesthesia
  • UCSD Hillcrest
  • March 28, 2012

2
Hypertension in pregnancy
  • Pre-eclampsia (HBP, proteinuria, edema, after 20
    weeks ega)
  • Gestational hypertension (HBP after 20 weeks ega,
    no proteinuria). Old term pregnancy-induced
    hypertension.
  • Chronic hypertension (HBP antedating pregnancy).
  • Superimposed pre-eclampsia pre-eclampsia on
    top of chronic hypertension

3
Three causes of death in pregnancy
  • 1 Pulmonary thromboembolism
  • 2 Hemorrhage
  • 3 Hypertensive disorders / pre-E
  • Stroke
  • Seizures
  • DIC

4
Pre-eclampsia variants
  • Eclampsia pre-eclampsia with seizures
  • HELLP syndrome (hemolysis, elevated liver enzymes
    and low platelets)

5
Severe pre-eclampsia
  • SBP gt 160 or DBP gt 110, X2, 6 hours apart.
  • Proteinuria gt 5 gm / 24 hours (Hence 24-hour
    urine collection)
  • Oliguria lt 500 mL / 24 hours

6
Severe pre-eclampsia
  • Cerebral or visual disturbances HA, blurred
    vision or altered consciousness.
  • Pulmonary edema (or low Sp02).
  • Epigastric or RUQ pain (liver edema or rupture)

7
Severe pre-eclampsia
  • Increased liver enzymes-- common.
  • Prolonged PT or PTT or decreased fibrinogen
    implies DIC fortunately rare.
  • Thrombocytopenia
  • Fetal growth restriction

8
Traditional pre-eclampsia triad
  • Hypertension
  • Proteinuria
  • Edema

9
New understanding of traditional pre-eclampsia
triad
  • Hypertension? arteriolar constriction
    (endothelial dysfunction).
  • Proteinuria? leaky glomerulus (capillary)
    (endothelial dysfunction).
  • Edema? leaky capillaries in skin, muscle, liver,
    brain, airway, nose. (endothelial dysfunction).

10
4th component of endothelial dysfunction in
pre-eclampsia
  • Muscular artery spasm? increased arterial wave
    reflection back to heart?
  • Increased augmentation index (AIx)
  • Increased AIx? extra work for heart muscle?
  • LVH, increased BNP release? CHF.

11
Modern concept of pre-eclampsia symptoms are due
to arterial, arteriolar and capillary
endothelial damage.
  • Q Damage by what?
  • A Chemical mediators from placenta

12
Toxemia of pregnancy
  • The old-fashioned term is actually very
    descriptive!
  • The ischemic placenta gives off toxins which
    damage the mothers vascular endothelium
    throughout her body.

13
Pre-eclampsia ischemic chorionic villi release
pre-E mediators into maternal blood.
Say OUCH!
Pre-E mediators
Poor placentation
www.siumed.edu/dking2/erg/images/placenta.jpg
14
Pre-E endothelial damage
  • Deranged smooth muscle function, due to damaged
    endothelium overlying smooth muscle.
  • Leaky capillary endothelium (no smooth muscle).

15
Endothelial cells send molecular signals to
surrounding smooth muscle
Insulin makes endothelium produce
Pre-eclampsia mediators (and glucose) make
endothelium produce
vasodilatory signals (NO, prostacyclin)
Vessel lumen
vasoconstrictive signals (thromboxane, endothelin)
Archer TL 2006 unpublished, Idea from Dandona P
2004
16
Endothelial factors in pre-E
  • In health, there is a balance between
  • vasodilatory factors NO, PGI2 (Prostacyclin) and
  • vasoconstrictive factors thromboxane,
    endothelin.
  • This normal balance is messed up in pre-E.

17
Obesity, hyperglycemia, sepsis and pre-eclampsia
all activate (damage) endothelium, white cells
and platelets, leading to white cell adhesion and
infiltration, thrombosis and edema (inflammation).
WBC
WBC
Obesity, hyperglycemia, sepsis or pre-eclampsia
Platelet
Platelets
Capillary endothelium (no underlying smooth
muscle)
Protein (edema)
Archer TL 2006 unpublished
18
Endothelial damage causes problems in 3 sizes of
blood vessels
  • Muscular arteries? increased wave reflection
    (heart work, augmentation index).
  • Arterioles? increased SVR
  • Capillaries? proteinuria and tissue edema
    (glomerulus, liver, skin, muscle, brain)

19
Figure 1. Pt HB, PreE for CS, superimposed on
CHTN and CRF, 33 weeks. Hemodynamic parameters
before and after treatment with antihypertensive
medication A. Labetalol 25 mg and hydralazine 5
mg, B. Nicardipine 250 µ total in divided doses
20
Posterior reversible encephalopathy syndrome
(PRES) Occipital-parietal cortical and white
matter changes in pre-eclampsia. Is this due to
capillary damage in the brain?
Port JD, Beauchamp RadioGraphics 1998
18353-36i
21
Figure 1b
22
Figure 1c
23
Edema imagine same process in liver and brain!
24
Pre-eclampsia
  • Probably a
  • disorder of placentation.

25
(No Transcript)
26
Poor-placentation theory of pre-E Synciotrophobla
st invades myometrium but does not denervate
spiral arteries of mother properly. Hence,
intervillous flow is sub-optimal. Chorionic villi
are ischemic and release mediators (VEGF, etc)
which damage maternal endothelium.
http//pharyngula.org/images/preeclampsia_model.jp
g
27
Pre-eclampsia ischemic chorionic villi release
pre-E mediators into maternal blood.
Say OUCH!
Pre-E mediators
Poor placentation
www.siumed.edu/dking2/erg/images/placenta.jpg
28
Hemodynamic review
MAP SVR x CO. We ignore CVP since it is small
compared to MAP.
29
Hemodynamic issues in pre-eclampsia
  • We could work on CO or SVR, since
  • MAP CO x SVR.
  • We usually work on both CO and SVR, but different
    drugs affect the two components to different
    degrees.

30
SAB / epidural cause sympathectomy
www.cvphysiology.com/Blood20Pressure/BP019.htm
31
Post-partum BP control
  • Hydralazine arteriolar vasodilator. Decreases
    SVR. Tendency is to cause tachycardia. 5 mg IV
    q15 minutes
  • Labetalol alpha and beta blocker. Dilates
    arterioles (dec SVR) and slows heart rate and
    reduces contractility (dec CO). 10-20 mg IV q 10
    minutes.

32
Why treat BP in pre-eclampsia?
  • Decrease stroke, CHF, renal damage?
  • This has never been proven by RCT.
  • But we do it anyway!
  • Goal is modest decrease in BP. DBP 90-100 mm Hg.

33
Other BP meds in pre-eclampsia
  • Nitroglycerin venodilator, can be given
    sublingually or IV.
  • Sodium nitroprusside IV. Needs arterial
    line.Primarily arteriolar dilator.
  • Nifedipine Ca channel blockers. Arteriolar
    dilator. Can be used for BP control and also as a
    tocolytic. Caution should be used when used with
    Mg.
  • Esmolol sort acting beta blocker. Adjunct to
    decrease HR in BP control.

34
Pre-eclampsia complication pulmonary edema
  • Fluid overload / pulmonary edema
  • respiratory distress
  • Low SpO2 (low sats)
  • Rales on auscultation
  • Can progress to ARDS
  • May need intubation
  • Call anesthesia for evaluation

35
Pre-eclampsia complications pulmonary edema
  • Fluid overload / pulmonary edema
  • Albumin (oncotic pressure) decreases in normal
    pregnancy.
  • Lower in pre-eclampsia due to protein loss into
    interstitial space

36
Respiratory function in pre-eclampsia
  • Edema of the airway

37
Pre-eclampsia complications blindness and
seizures
  • Blindness / blurred vision
  • Edema in occipital cortex (retina is normal)
  • Disorientation / fear
  • Visual impairment usually resolves completely

38
Pre-eclampsia complications blindness and
seizures
  • Seizure neurological event but also a
    respiratory event!
  • Remember suction, oxygen, ambu bag, IV access,
    call anesthesiologist to help.
  • Ante-partum, fetal oxygenation is at risk.

39
MgSO4 seizure prophylaxis
  • Mg in severe pre-E reduces seizures by about
    60 (from 1.9? 0.8)
  • Mg use in mild pre-eclampsia is controversial
    but it is used at UCSD.

40
Magnesium toxicity
  • 1.7-2.4 mg / dL Normal
  • 5-9 mg / dL therapeutic range for seizure
    prevention
  • Loss of patellar reflexes (but watch out for
    epidural) 12 mg / dL
  • Respiratory arrest 15-20 mg / dL
  • Asystole 25 mg / dL
  • Mg levels OK, but try clinical assessment!

41
Magnesium toxicity
  • Multiple blood draws think central or arterial
    line or blue valve from IV catheter. Avoid
    repeated sticks?
  • Treatment
  • Stop Mg
  • Give Ca (1 gm Ca gluconate or 300 mg CaCl2
  • Assist ventilation (Ambu bag). Intubation if
    necessary.

42
Magnesium toxicity
  • Uterine atony (Mg is a uterine relaxant)

43
Hematologic aspects of pre-E
  • Exacerbated normal hypercoagulability of normal
    pregnancy.
  • If DIC occurs, fibrinolysis will occur as well (
    Fibrin dimer test)
  • Platelet activation and adhesion / consumption.
  • We commonly follow trend of platelets.
  • Regional OK if gt 50-100K.

44
Prolongation of PT / PTT or decreased fibrinogen
in pre-E
  • Uncommon (thrombocytopenia is common).
  • Low fibrinogen implies DIC.
  • Liver damage? decreased synthesis of fibrinogen
    and clotting factors?
  • Bottom line if fibrinogen or PT/PTT are
    abnormal, patient has a more serious problem than
    just thrombocytopenia.

45
Pre-eclampsia complications
  • Disseminated intravascular coagulation (DIC)
  • Consumption of platelets and clotting factors d/t
    damaged endothelium
  • Diffuse ooze from incision, IV sites
  • Major emergency
  • IV access, pRBCs, FFP, cryoprecipitate
  • Will need ICU, ?intubation, arterial line

46
Hemolysis from fibrin stands
www.nejm.org/.../2005/20050804/images/s19.jpg
47
Liver in pre-eclampsia
  • Elevated liver enzymes (AST, ALT)
  • Edema swelling epigastric / RUQ pain
  • Hemorrhage into liver (hematoma)
  • Rupture of hematoma through liver capsule (liver
    rupture).

48
Factitious thrombocytopenia
  • Platelet clumping due to EDTA anticoagulant or
    cold

www.nejm.org/.../2005/20050804/images/s19.jpg
49
Renal function in pre-eclampsia
  • Normal pregnancy involves increased GFR and
    decreased creatinine, e.g. 0.8?0.6 mg/dL.
  • Renal dysfunction in pre-eclampsia may be
    associated with a normal creatinine, eg. 1.0.
  • Increased uric acid in pre-eclampsia

50
Renal failure after pre-E
  • Oliguria almost always gets better after
    delivery.
  • Renal failure due to pre-E is rare (unless there
    is pre-existing renal disease).

51
Oliguria
  • Urine output less than 30 mL / hr for more than 3
    hours, despite crystalloid boluse(s) of 300-500
    mL.
  • Is the Foley in the bladder? Is it kinked?

52
Summary
  • Pre-eclampsia is associated with endothelial
    dysfunction.
  • Normal balance between vasodilation and
    vasoconstriction tips toward constriction.
  • Capillaries become leaky edema (and proteinuria)
    everywhere.

53
Summary
  • Old-fashioned term toxemia of pregnancy is very
    accurate!
  • Placenta is ischemic because implantation has not
    gone well.
  • Pre-eclampsia a disorder of implantation.

54
Summary
  • Pre-eclampsia may involve an early hyperdynamic
    phase (increased CO), followed by a
    vasoconstrictive phase (high SVR).
  • Later on, pre-eclampsia involves intense
    arteriolar constrictive, with high BPs and
    reflected pressure waves leading to heart strain
    and possible CHF.

55
Summary
  • The endothelial damage of pre-eclampsia can
    activate the coagulation system.
  • Thrombocytopenia occasionally occurs but
    hypofibrinogemia and prolonged PT/PTT are rare
    and very worrisome.

56
Overall management
  • Seizure prophylaxis
  • Hemodynamic stateinvasive monitoring
  • Fluid restriction (but boluses for oliguria).
  • Review of platelets, PT, PTT, fibrinogen
  • Evaluation of airway (swelling) and pulmonary
    status (edema)
  • Pulmonary edema most common after delivery
    (mobilization of edema fluid).

57
Neonatal issues in pre-eclampsia
  • IUGR
  • Prematurity
  • Hypoxia
  • Mother will be afraid for the baby!

58
Maternal CNS issues in pre-eclampsia
  • Confusion or somnolence due to cerebral edema
  • Somnolence due to MgSO4 therapy
  • Post-ictal state (has patient had a seizure?)
  • Is patient afraid?

59
Summary care for patient with severe pre-eclampsia
  • Emotional support anxiety for self, neonate, CNS
    changes due to disease and therapy.
  • Pain from surgery helped by neuraxial anesthesia
    and neuraxial opioids.

60
Summary of care for patient with severe
pre-eclampsia
  • Follow BP may increase as spinal wears off. This
    is normal.
  • Goal of BP control is high normal dont
    overshoot.
  • Treat pain, not just give antihypertensives.

61
Summary of care for patient with severe
pre-eclampsia
  • Judicious fluid restriction (unless post-partum
    hemorrhage).
  • Continue magnesium sulfate.
  • Monitor urine output.

62
Summary of care for patient with severe
pre-eclampsia
  • Monitor for post-partum hemorrhage
  • Prolonged labor, MgSO4 can predispose to uterine
    atony.
  • Monitor for DIC. Oozing at IV and other
    venipuncture sites.

63
How can anesthesiologist help the patient in the
PACU?
  • IV access central line or arterial line for
    repeated blood draws and BP monitoring?
  • IV med assistance what to give? How fast will it
    work?
  • Monitor for pulmonary / cardiac dysfunction
    rales, low Sp02.

64
How can anesthesiologist help the patient in the
PACU?
  • Manage seizing patient airway, vomiting.
  • Have suction, ambu bag, crash cart nearby.

65
The End
About PowerShow.com