A retrospective review of the medical records of all patients admitted to the CVICU at Lucile
packard children 's hospital at stanford,California from October 16, 2010, through January 31 , 2011,was conducted. The investigation reviwed electronic medication administeation records to determine the frequency and timing of as-needed medicattion usage to treat pain and achieve sedation. Data collection included surgical date and the time of as-needed sedative and analgesic drug administeation for each patient during the study period. Doses were separated on the basis of time of day , administered and categorized as given during the day (7 am-7 pm) or the night shift (7 pm -7 am ). The institutional review board found found this investigation be exempt from approval.