Comparison of Bispectral Index Values in Patients With and Without Down's Syndrome

Overview

About 1 in every 700 babies born in the United States has Down's Syndrome (DS; Trisomy 21), 99% of whom have some degree of intellectual disability. Recent advances in medicine have resulted in a dramatically improved lifespan of about 25 to 60 years of age. Yet, there is limited data about anesthetic management in this increasing patient population. The bispectral index (BIS) monitor is a non-invasive monitoring device that reports a value between 0 and 100correlating to level of consciousness of an individual. A value of 0 indicates lack of brain activity while 100 indicates an awake/alert state. This monitor can be used to assess the depth of anesthesia. Patients with intellectual disability from congenital neurological diseases have lower BIS values compared to patients without any neurological impairment (Valkenburg 2009). The results may suggest that DS patients would require less anesthetic drugs compared to patients without any neurological impairment. To date, there are no studies in DS patients.

Based on the Valkenburg group's study (2009), one might hypothesize that if the BIS value is fixed for all patients, then a patient with an intellectual disability such as a patient with DS would require less anesthetic drugs compared to a control patient without any neurological disability. However, if one is only using a clinical sedation scale, the DS patient may receive more anesthetic drugs in order to achieve the same level of clinical unconsciousness as a patient without DS. This project seeks to elucidate the effect of anesthetic techniques and agents on patients with DS compared to those without DS and any intellectual disability. The goal of this project is to compare BIS values in patients with DS to those without DS undergoing a standardized general anesthetic technique. The investigators hypothesize that patients with DS would have lower (\>25%) BIS values compared to those without DS. Known potential sources of artifact signals that could change BIS values include electromyographic activity, electric devices, hypothermia, hypoglycemia, and the timing and type of anesthetics used (Duarte 2009, Dahaba 2005). These potential sources will be identified and reported during the study, and those patients will be excluded from the study