Perioperative Stroke: Comment

The review by Vlisides and Moore¹  did not mention a recently identified group of genetic disorders posing a significant risk for stroke, the most common of which is CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy).^2,3  CADASIL is caused by an autosomal dominant defect in the NOTCH3 gene, causing abnormal, fragile vascular smooth muscle and resulting in early stroke and dementia in a genetic pattern similar to Huntington disease: 1 per 10,000 prevalence with 50% of offspring affected in mid-adulthood. Although a large hospital will likely encounter several CADASIL patients each year, the disease is rarely diagnosed or reported.⁴ 

CADASIL is readily identified by the history, and so I have added two questions to my preoperative questionnaire: “Do you have blood relatives with stroke and dementia before the age of 60?” (positive in 85% of CADASIL patients), and “Do you have adult-onset migraine headaches with aura?” (positive in 50%).²  When CADASIL is suspected, a preoperative neurology consult may aid perioperative management. Laboratory studies to confirm the diagnosis include genetic testing, brain MRI showing diffuse white matter disease, and abnormal vasculature observed by skin biopsy or fundoscopic exam. Once the diagnosis is established, no further studies are recommended.⁴ 

There are no published guidelines on anesthetic management of CADASIL. These patients are at increased risk for stroke, thus performing surgery at a hospital with a stroke unit may be prudent. Project OrphanAnesthesia suggests maintaining “cerebral perfusion pressure through systemic arterial pressure, and volume replacement. If needed, direct vasopressors are preferred, but the indirect ones have been used without problems (low dose). Both hypo- and hypercapnia should be avoided because the limits of autoregulation of the diseased vessels are not known.”⁴  General anesthesia in the sitting position, which has been associated with decreased cerebral blood flow and rare perioperative strokes,⁵  should be used judiciously or avoided. Postoperatively, CADASIL patients should be monitored as described by Vlisides and Moore. Awareness of CADASIL may reduce perioperative morbidity in this vulnerable population.

The author declares no competing interests.