Preemptive dexmedetomidine to prevent propofol injection pain in children

Abstract

Background: The incidence of propofol injection pain is high in children, but no methods have been found to suppress it completely. This study intends to evaluate the efficacy of dexmedetomidine-midazolam in preventing propofol injection pain in children.

Methods: One-hundred ASA I patients, aged 3-12 years, weighing 15-53 kg, undergoing elective surgery were randomized into two groups of 50 each, using computer-generated random numbers. Normal saline 0.15 ml/kg in Group C or dexmedetomidine 0.6 μg/kg in Group D was infused IV over 10 min. Then midazolam 0.06 mg/kg was administered immediately; 2 min after aforementioned treatments in each group, all patients received propofol 2 mg/kg (propofol was mixed with lidocaine 1 mg/ml in Group C) at an average rate of 0.2 ml per 1 s. Another anesthesiologist, blind to the pretreatment, recorded the occurrence of injection pain using a four-graded pain scale: 1 = no pain (no reaction to injection), 2 = slight pain (minor verbal/facial response or motor reaction to injection), 3 = moderate pain (clear verbal/facial response or motor reaction to injection) and 4 = severe pain (the patient both complained of pain and withdrew the arm).

Results: Forty (80 %) patients in Group C (control) had injection pain; however, none of patients in Group D had any injection pain. The total incidence of profol-induced pain in Group C was significantly higher (P < 0.01). There were no instances of bradycardia or low blood pressure with either treatment in this study.

Conclusions: Pretreatment with dexmedetomidine 0.6 μg/kg, then midazolam 0.06 mg/kg could suppress propofol injection pain in children.