Background: Pain, anxiety and fear of needles make intravenous cannulation extremely difficult in children. We assessed the efficacy and safety of oral midazolam and a low-dose combination of midazolam and ketamine to reduce the stress and anxiety during intravenous cannulation in children undergoing computed tomography (CT) imaging when compared to placebo.
Methods: Ninety-two ASA I or II children (1-5 years) scheduled for CT imaging under sedation were studied. Children were randomized to one of the three groups. Group M received 0.5 mg x kg(-1) midazolam in 5 ml of honey, group MK received 0.25 mg x kg(-1) midazolam mixed with 1 mg x kg(-1) ketamine in 5-ml honey and group P received 5-ml honey alone, orally. In 20-30 min after premedication, venipuncture was attempted at the site of eutectic mixture of local anesthetics cream. Sedation scores and venipuncture scores were recorded. Primary outcome of the study was incidence of children crying at venipuncture (venipuncture score of 4).
Results: Significantly more children cried during venipuncture in placebo group compared to the other two groups (19/32 (59%) in group P vs 1 each in groups M and MK, (P < 0.001) (RR 2.37, 95% CI 1.55-3.63). In 20-30 min after premedication, group P had more children in sedation score 1 or 2 (crying or anxious) compared to the other two groups (P < 0.05). At this time, group MK showed more children in calm and awake compared to group M (P = 0.02). At venipuncture, group P had more children in venipuncture score 3 or 4 (crying or withdrawing) compared to group M or MK (P < 0.05), while groups M and MK were comparable.
Conclusion: A low-dose combination of oral midazolam and ketamine or oral midazolam alone effectively reduces the stress during intravenous cannulation in children undergoing CT imaging without any adverse effects. However, the combination provides more children in calm and quiet state when compared to midazolam alone at venipuncture.