Anesthetic Considerations for the Patient with Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Syndrome)

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Anesthetic Considerations for the Patient with Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Syndrome) Powered By Docstoc
					Anesthetic Considerations for the Patient
with Hereditary Hemorrhagic Telangiectasia
(Osler-Weber-Rendu Syndrome)

Kathleen M. Z. Peiffer, CRNA, MSN

 Hereditary hemorrhagic telangiectasia (HHT), Osler-           organ systems. Anesthetic care of patients with HHT
 Weber-Rendu Syndrome, is an uncommon disease but              involves very specific interventions with regard to
 may be present in many people who remain undiag-              control of bleeding, maintaining adequate oxygena-
 nosed. It is an autosomal dominant disorder charac-           tion, and balancing hemodynamic values to optimize
 terized by multiple arteriovenous malformations               perfusion without compromising anesthetic depth.
 (AVMs) and telangiectases that affect multiple organ
 systems. Hereditary hemorrhagic telangiectasia
 patients have a propensity for bleeding, especially           Keywords: Arteriovenous malformations, hereditary
 from the oropharynx, nasopharynx and gastrointesti-           hemorrhagic telangiectasia, Osler-Weber-Rendu syn-
 nal tract, as well as from rupture of AVMs of other           drome, telangiectasia.



             ereditary hemorrhagic telangiectasia (HHT),       (41% incidence).1 Up to 15% of individuals have at least



H            also known as Osler-Weber-Rendu syndrome,
             is an autosomal dominant vascular dysplasia
             that affects multiple organ systems. The con-
             dition is characterized by the lack of commu-
nicating capillaries connecting arteries and veins resulting
in multiple arteriovenous malformations (AVMs) and
telangiectases.1 Telangiectases are small AVMs that lie just
                                                               1 cerebral AVM and although the incidence of hepatic
                                                               AVMs is unknown, those reported are quite large.1,3
                                                               Pulmonary arteriovenous malformations (PAVMs) may
                                                               occur in as many as 50% of patients with HHT and are a
                                                               significant cause of morbidity.1,4
                                                                   Pulmonary arteriovenous malformations are often of
                                                               such significance to cause a right-to-left shunt resulting in
beneath the surface of mucous membranes and skin and           hypoxemia and/or heart failure.3,5 In normal lungs the
are easily ruptured with resultant bleeding.                   capillary matrix connecting the arteries and veins acts as
    Arteriovenous malformations are arteries and veins that    a filter for thrombi, air, and bacteria. In the absence of this
are connected without the usual capillary bed.2 Without        filtering network they pass directly into arterial circula-
normal growth, the arterial vessels become thinner causing     tion. If this material becomes lodged in small arterioles, it
shunting of arterial blood to the venous system, from high     may result in dyspnea, hypoxemia, and pulmonary hem-
pressure to low pressure without the capillary network that    orrhage, as well as ischemic strokes and brain abscesses
predisposes them to rupture. Arteriovenous malformations       with subsequent neurological deficits.
have the capacity for rupture and resultant hemorrhage re-         Hepatic AVMs also impose a great risk to the patient
gardless of their location.                                    with HHT. Liver complications are noted in up to 31% of
    Although this condition is considered to be uncom-         HHT cases including hepatic fibrosis and cirrhosis.6
mon, it is not rare. As many as 1:5,000 individuals are af-    Hepatic AVMs cause shunting to occur and may allow
fected and many more are thought to be living with this        thrombi, bacteria, and other infiltrates from the enteric
disease undiagnosed.1 Diagnostic criteria include (1) a        circulation into the systemic circulation.1,3 Loss of the
first-degree relative (parent, sibling, or child) with the     downgrade of pressure from arteries to veins creates a
disorder, (2) telangiectases of lips, nose, oral cavity,       high pressure blood flow through the hepatic portal
and/or fingers, (3) any of the internal AVMs discussed         system and vena cava. This high-pressured blood flow re-
above or gastrointestinal (GI) telangiectasia, and (4) re-     turning to the right side of the heart may result in right
current, spontaneous epistaxis. The presence of 3 of the       heart failure from hyperdynamic circulation.3 Likewise,
above symptoms is definitive for a diagnosis of HHT. The       portal hypertension may occur subsequent to a throm-
patient with 2 of these symptoms is likely to have HHT         botic event in the liver resulting in esophageal varices. A
and shoul
				
DOCUMENT INFO
Description: Hereditary hemorrhagic telangiectasia (HHT), Osler-Weber-Rendu Syndrome, is an uncommon disease but may be present in many people who remain undiagnosed. It is an autosomal dominant disorder characterized by multiple arteriovenous malformations (AVMs) and telangiectases that affect multiple organ systems. Hereditary hemorrhagic telangiectasia patients have a propensity for bleeding, especially from the oropharynx, nasopharynx and gastrointestinal tract, as well as from rupture of AVMs of other organ systems. Anesthetic care of patients with HHT involves very specific interventions with regard to control of bleeding, maintaining adequate oxygenation, and balancing hemodynamic values to optimize perfusion without compromising anesthetic depth.
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