PREGNANCY INDUCED HYPERTENSION AND HELLP SYNDROME

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PREGNANCY INDUCED HYPERTENSIONAND HELLP SYNDROME

• DENNIS STEVENS CRNA, MSN, ARNP
• JANUARY 2006
• FLORIDA INTERNATIONAL UNIVERSITY
• PRICIPLES ANESTHESIOLOGY NURSING II
• NGR 6093

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OBJECTIVES

• Discuss pathophysiology and manifestations
  associated with preeclampsia including
  predisposing risk factors.
• Explain complications associated with PIH and how
  body systems are affected.
• Describe current treatment modality for PIH
  including use of magnesium sulfate therapy.
• Construct an anesthetic care plan for the
  parturient with HELLP syndrome receiving a
  cesarean section secondary to breech presentation.

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REFERENCES

• Chestnut, D.H. (1999). Obstetric Anesthesia. (2nd
  Ed.).
• St. Louis, MO Mosby.
• Morgan, G.E., Mikhail, M.S., and Murray, M.J.
  (2002).
• Clinical Anesthesiology. (3rd Ed.). New York,
  NY
• McGraw-Hill.

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HYPERTENSIVE DISORDERS OF PREGNANCY

• PIH also known as preeclampsia
• Eclampsia present when seizures superimposed on
  preeclampsia
• HELLP syndrome
• (H) hemolysis, (EL) elevated liver enzymes, (LP)
  low platelet count

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INTRODUCTION

• PIH (preeclampsia) refers to the triad of
  hypertension, proteinuria, and edema occurring
  after the 20th week of gestation and resolving
  within 48 hours after delivery
• PIH defined as SBP gt 140 mmHg or DBP gt 90 mmHg
• Eclampsia is present when seizures are
  superimposed on preeclampsia. Occurs in 5 of
  parturients who develop PIH
• Preeclampsia and eclampsia complicate 7-10 of
  pregnancies
• Severe PIH significantly increases both maternal
  and fetal morbidity and mortality. May be
  associated with HELLP syndrome
• PIH not preventable. Treatment essentially
  restricted to addressing manifestations and side
  effects

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PATHOPHYSIOLOGY AND MANIFESTATIONS

• Several predisposing factors associate with
  preeclampsia
• Inadequate uterine perfusion has an important
  role in the etiology of PIH and HELLP syndrome
• Appears to be related to abnormal prostaglandin
  metabolism and endothelial dysfunction leading to
  vascular hyperreactivity
• Patients with preeclampsia develop an imbalance
  between plasma thromboxane and prostacyclin,
  allowing thromboxanes effects to predominate
• Other manifestations of PIH

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PATHOPHYSIOLOGY AND MANIFESTATIONS

• Severe PIH defined by a blood pressure gt 160/110
  mmHg, proteinuria in excess of 5 g/d, oliguria,
  pulmonary edema, CNS manifestations, hepatic
  tenderness, or HELLP syndrome
• Patients with severe preeclampsia or eclampsia
  have differing hemodynamic profiles. Most
  patients have low-normal cardiac filling
  pressures with high systemic vascular resistance,
  CO may be low, normal, or high
• In HELLP syndrome striking hepatic changes occur
• Hemolysis associated with HELLP syndrome is
  consistent with microangiopathic hemolytic anemia
• Low platelet count associated with HELLP syndrome
  appears to be due to increased peripheral
  vascular destruction

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COMPLICATIONS OF PIH

• Neurologic
• Pulmonary
• Cardiovascular
• Hepatic
• Renal
• Hematologic

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TREATMENT

• Restricted to addressing manifestations and side
  effects associated with this disease
• Treatment consists of bed rest, sedation,
  antihypertensive medications, and magnesium
  sulfate therapy
• Invasive arterial, central venous, and possibly
  pulmonary artery monitoring may be indicated in
  patients with severe hypertension, pulmonary
  edema, or refractory oliguria
• Definitive treatment is delivery of the fetus and
  placenta!

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ANESTHETIC MANAGEMENT

• Patients with severe disease require
  stabilization prior to the administration of any
  anesthetic. Hypertension should be controlled and
  hypovolemia corrected. In the absence of
  coagulopathy, continuous epidural anesthesia is
  the anesthetic of choice for most patients with
  PIH
• Platelet count and coagulation profile should be
  checked prior to initiation of regional
  anesthesia in patients with severe PIH
• Intra-arterial blood pressure monitoring
  indicated for severe hypertension. Central venous
  line may guide volume replacement. Pulmonary
  artery may also be indicated
• Magnesium sulfate potentiates muscle relaxants

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SUMMARY

• Preeclampsia is a multi-system disorder producing
  maternal morbidity and mortality
• Magnesium sulfate remains the agent most often
  used to prevent seizures in the preeclamptic
  patient. If convulsions occur, they should be
  immediately treated with intravenous
  benzodiazepines or thiopental
• Indications for invasive monitoring include
  severe oliguria, pulmonary edema, and severe
  hypertension unresponsive to aggressive
  pharmacologic management
• Epidural anesthesia provides numerous maternal
  and fetal benefits to the preeclamptic patient