Evaluating the hematoma block as an adjunct to procedural sedation for closed reduction of distal forearm fractures.

OBJECTIVES: Although procedural sedation using intravenous agents is highly effective for forearm fracture reduction, the process is both resource and time intensive. Our objective was to determine whether the use of a hematoma block as an adjunct to procedural sedation with ketamine and midazolam reduces (1) pain during the procedure (scored using the Observational Score for Behavioral Distress-Revised score) or (2) the excess sedation time, defined by the time between procedure completion and discharge from sedation. Our secondary outcome measure was total ketamine dose administered during the procedure.

METHODS: A randomized, double-blind, placebo-controlled clinical trial was conducted. Before fracture reduction, children 3 to 17 years of age randomly received 2% lidocaine (L) or normal saline (NS) into the hematoma of their fracture site during sedation with intravenous ketamine and midazolam.

RESULTS: Ninety patients were randomized: 50 to L and 40 to NS. The groups were similar with regard to age, sex, type of fracture, and prior administration of pain medication. Median Observational Score for Behavioral Distress-Revised scores were 1.11 and 1.69 for the L and NS groups, respectively (P = 0.23). Excess sedation time was not significantly different between the groups (P = 0.36), with a median excess sedation time of 33.0 and 36.0 minutes for the L and NS groups, respectively. Mean ketamine dose administered was not different between the groups (P = 0.42). The mean total dose administered was 1.00 mg/kg and 1.07 mg/kg in the L and NS groups, respectively. Mean midazolam dose was 0.05 mg/kg for both groups.

CONCLUSIONS: The use of a hematoma block as an adjunct to procedural sedation with ketamine and midazolam for forearm fracture reduction conferred no additional benefit and did not decrease observed pain scores, excess sedation time, or total ketamine dose administered.