Study Objective
To estimate the minimum dose and total sedation time of rapidly infused ketamine that achieves 3-5 minutes of effective sedation in children undergoing forearm fracture reduction in the emergency department.
Methods
We used the Up-Down method to estimate the median dose of intravenous ketamine infused over ≤ 5 sec that provided effective sedation in 50% (ED50) and 95% (ED95) of healthy children aged 2-5, 6-11 or 12-17 years undergoing forearm fracture reduction. Most were pretreated with opioids. Three investigators blinded to ketamine dose independently graded sedation effectiveness by viewing a video recording of the first 5 minutes of sedation. Recovery was assessed by Modified Aldrete score.
Results
We enrolled 20 children in each age group. The estimated ED50 was 0.7, 0.5 and 0.6 mg/kg and the estimated ED95 was 0.7, 0.7 and 0.8 mg/kg for the 2-5, 6-11 and 12-17 years age groups, respectively. For the 2-5 years age group, an empirically derived ED95 was 0.8 mg/kg. All who received the empirically derived ED95 in the 2-5 years group or the estimated ED95 in the 6-11 and 12-17 years group had effective sedation. The median total sedation time for the three age groups respectively, was 25, 22.5 and 25 minutes if one dose of ketamine was administered and 35, 25 and 45 minutes if additional doses were administered. No participant experienced serious adverse events.
Conclusions
We estimated ED50 and ED95 for rapidly infused ketamine for three age groups undergoing fracture reduction. Total sedation time was shorter than most previous studies.