Children 4–18 years old who received intravenous morphine during a tonsillectomy and adenoidectomy at the Children’s Hospital of Philadelphia (CHOP) were identified using the Anesthesia Information Management system (CompuRecord, Phillips Medical Systems, Andover, MA). All surgeries were performed between November 1, 2001 and December 1, 2009. Exclusion criteria included obstructive sleep apnea, a combination of tonsillectomy and adenoidectomy with another procedure, or administration of other intraoperative anesthetics. While recovering in the Postanesthesia Care Unit (PACU), children received additional intravenous morphine (in 25–50 μg/kg increments) to control their pain. The CHOP IRB approved collection of these data.
