Combination of dexmedetomidine with retrobulbar block in pediatric patients undergoing enucleation of eyeballs

Objective To evaluate effects of retrobulbar block combined with dexmedetomidine(Dex) on intraoperative management, postoperative pain, and recovery quality in pediatric patients undergoing enucleation of eyeballs. Methods Forty five pediatric patients(1-6 years) scheduled for enucleation of eyeballs were enrolled and randomly assigned into 3 groups(n=15), respectively received retrobulbar block combined with Dex(group ND), retrobulbar block(group N), and Dex(group D). In group ND, 0.5 μg/kg Dex was infused within 10 min after induction of anesthesia, and retrobulbar nerve block was achieved by surgeon before enucleation of eyeballs. In group N, retrobulbar nerve block was achieved before enucleation of eyeballs. In group D, 0.5 μg/kg Dex was administrated after induction of anesthesia. The MAP and HR were recorded before (T1), during (T2), and after (T3) the placement of orbital implant, and immediately after the removal of laryngeal mask airway(T4) and leave from PACU(T5). The pain scales, postoperative analgesics usage, nausea, and vomiting were assessed 2, 6 h and 24 h after operation. The perioperative adverse events were also recorded. Satisfaction regarding sleeping and pain condition was rated by parents 24 h after operation. Results The incidence of bradycardia during orbital implant placement was lower in group ND(8.3%) and group N(0) than in group D(41.7%, P<0.05). Pain scales in group ND[0(1), 0(1)] were lower than those in group N [2(2), 2(1)] and group D [3(1), 2(1)] 2 h and 6 h after operation(P<0.05), but not 24h after operation. In group ND, patients used less anal acetaminophen compared with other two groups. The severity of nausea and vomiting(no less than 2) in group ND and group N was significantly lower than that in group D. Satisfactory scores were the highest in group ND. Conclusions Retrobulbar block combined with Dex decreased oculocardiac reflex during enucleation of eyeballs in pediatric patients, and provided more satisfactory analgesic effects with fewer incidences of nausea and vomiting. Key words: Pediatric; Eye enucleation; Dexmedetomidine; Retrobulbar block