Subtenon versus intravenous Dexmedetomidine injection for postoperative analgesia in infantile cataract surgery: double-blind randomized clinical trial

Abstract

ABSTRACT Background Subtenon block (SB) is one of the optimal opioid-free modalities for pain alleviation in cataract extraction surgery. Dexmedetomidine can be used as an adjuvant to local anesthetic regional blocks offering better analgesia. Our primary novel goal is to study the effect of dexmedetomidine-bupivacaine SB versus intravenous dexmedetomidine upon the number of infants who require postoperative analgesia after congenital cataract extraction. Methods: 80 infants undergoing cataract extraction were randomly allocated into two groups. SB group (n = 40) SB block done with a mixture of 0.05 ml/kg of 0.5% bupivacaine and 0.5 ug/kg dexmedetomidine, and IV group (n = 40) received 1 ug/kg dexmedetomidine intravenously after anesthesia inductions included the number of infants required rescue analgesia and CRIES pain score during the 1st four hours postoperatively. Results: The incidence of rescue analgesia need was significantly lower in the SB group 2 infants versus 11 in SB and IV groups in consequence (p = 0.006). CRIES score was of significantly lower values in SB group than IV group post-arousal at 20th and 40th min., and 1st,2nd, and 3rd hours (p-values; 0.01, 0.019, <0.001, <0.001, 0.001 in consequence). Limitation: No control group was included. Limitations: Lack of control group and short follow-up period. Conclusion: Subtenon block with a mixture of 0.5 ml kg of 0.5% bupivacaine and 0.5 ug/Kg dexmedetomidine offers advantages of being safe and more effective for postoperative analgesia over intravenous dexmedetomidine in infants undergoing cataract extraction surgery during the early postoperative period.