Beemer Lethal Malformation Syndrome

At a glance

Rapidly progressing, lethal genetic syndrome with cardiac, neurologic, hematologic, and skeletal anomalies.

Synonym

Beemer-van Ertbruggen Syndrome.

Incidence

Unknown, but surely exquisitely rare.

Genetic inheritance

Inheritance is most likely autosomal recessive with parental consanguinity as a risk factor.

Diagnosis

Based on the physical appearance, clinical course (lethal), radiologic imaging (dense bones), neuroradiologic imaging (hydrocephalus), echocardiography (double-outlet right ventricle, tetralogy of Fallot), and complete blood count (thrombocytopenia/leukocytosis).

Clinical aspects

Characterized by a variety of clinical abnormalities, which proved rapidly lethal in the reported cases. Craniofacial anomalies include wide cranial sutures with large anterior fontanel, down-slanting of the palpebral fissures, deep skin folds under the eyes, low-set and posteriorly rotated ears, broad nasal root and bulbous nose, long and deep philtrum and retrognathia. Urogenital anomalies include ambiguous external genitalia with enlarged clitoris, small scrotum without testes, and labioscrotal tumor. The bones appear abnormally dense on x-ray. The condition is associated with cardiac defects (double-outlet right ventricle, tetralogy of Fallot). Hydrocephalus, irritability, gasping, and generalized hypotonia have been described. A complete blood count may reveal severe thrombocytopenia and leukocytosis, which both seem to be transient with spontaneous recovery.

Precautions before anesthesia

No reports about anesthesia in these patients exist. Due to the dismal prognosis, these patients are unlikely candidates for anesthesia; however, anesthesiologists could be involved in the initial resuscitation attempts of these neonates born without an antenatal diagnosis of this syndrome. A thorough preoperative assessment is required to determine the extent of cardiac and neurologic anomalies. Recommended examinations to determine the appropriate management would include a cardiac consultation with electro- and echocardiogram, blood gas analysis to delineate the significance of the cardiac lesion and a complete blood count to rule out (or confirm) thrombocytopenia and leukocytosis. A neurologic investigation may include cranial CT- or MRI-scanning. Thrombocytopenia may require pre- or intraoperative platelet transfusions. The medical team and parents must have a clear treatment plan with realistic expectations.

Anesthetic considerations

The anesthetic technique must be tailored to the underlying cardiac lesion. Meticulous attention should be paid to avoid air bubbles in infusion-lines in patients with right-to-left shunts. In addition, induction and maintenance of anesthesia must take into consideration the potential for increased intracranial pressure in the presence of hydrocephalus. Early endotracheal intubation and mild hyperventilation will help to control intracranial pressure. Thrombocytopenia precludes the use of regional techniques. Preparations for prolonged postoperative ventilation and monitoring should be arranged.

Pharmacological implications

Care must be taken when sedative and narcotic agents are administered in the presence of hydrocephalus and raised intracranial pressure. Due to their dose-dependent myocardial depressant effects, intravenous and ...