Study to Find the Dose of Rapidly Administered Ketamine for Brief Painful Procedures in Children

The purpose of the study is to find the dose of rapidly administered ketamine in 3 different pediatric age groups (2-5, 6-11 and 12-17) for abscess drainage and fracture reduction. Ketamine is the most common drug administered to children to facilitate painful procedures in the emergency setting because it achieves potent sedation, pain relief and amnesia with minimal adverse cardiopulmonary effects.(1-5) However, the 1-2 hour recovery period (1,6) associated with standard ketamine administration guidelines(7) strains work flow because it requires bedside one-on-one nurse monitoring in a treatment room, tying up these limited and valuable resources. Consequently, a combination of two other drugs, propofol + fentanyl (P/F), with recovery of 20-30 minutes, is rapidly gaining popularity for procedural sedation despite more frequent respiratory depression, apnea and hypotension caused by this technique.(2,4,8,9) The investigators believe recovery associated with our novel method for administering ketamine is significantly shorter than with the standard larger dose more slowly administered ketamine technique(7). Through the investigators clinical experience, the investigators have found rapid infusion of smaller than standard doses of ketamine safely achieves the drug's sedative effect, with the benefit of more rapid recovery due to the use of a smaller dose. However, this novel technique challenges published beliefs that time of recovery from ketamine sedation does not differ significantly with the dose administered, within the usual dose ranges, and that rapid infusion may cause respiratory depression, similar to that seen with other classes of sedative-analgesic drugs.(7,10) the investigators believe the slow infusion recommended by standard guidelines(7) requires a larger ketamine dose necessary to achieve effective sedation, and, consequently, prolongs recovery. It is the prolonged recovery that has prompted increased use of other less safe but briefer sedatives,