tokens: Any pain during the reduction was rated by the orthopaedic surgeon treating the patient according to the Children ' s Hospital of Eastern Ontario Pain Scale ( CHEOPS ). RESULTS : The average time from intravenous administration of ketamine to manipulation of the fracture or dislocation was one minute and thirty - six seconds ( range , twenty seconds to five minutes ), and the average time from intramuscular administration to manipulation was four minutes and forty - two seconds ( range , sixty seconds to fifteen minutes ). The average score according to the Children ' s Hospital of Eastern Ontario Pain Scale was 6 .