Rocuronium versus dexmedetomidine as an adjuvant to local anesthetics in peribulbar block: A double blind randomized placebo controlled study

Objective
To compare the use of rocuronium with that of dexmedetomidine as an adjuvant to the local anesthetic mixture in peribulbar anesthesia for cataract surgery.
Design
A double blind, prospective, randomized controlled study.
Methods
Ninety patients with cataract in the age group 18–80 years of American Society of Anesthesiologists (ASA) physical status I–III scheduled for elective cataract surgery under regional anesthesia were randomly divided into three groups; Group C (control) received peribulbar anesthesia using a mixture of 4 ml lidocaine 2%, 4 ml bupivacaine 0.5%, and 1 ml normal saline. Group R received a mixture of 4 ml lidocaine 2%, 4 ml bupivacaine 0.5%, and 0.06 mg/kg rocuronium (maximum 5 mg) in 1 ml saline. Group D received a mixture of 4 ml lidocaine 2%, 4 ml bupivacaine 0.5%, and dexmedetomidine 50 μg (1 ml). Patients were assessed for onset and duration of corneal anesthesia and globe akinesia, postoperative pain using visual analog score (VAS), intraocular pressure (IOP), and sedation level using modified Ramsay sedation score (RSS). Patient and surgeon satisfaction score were also assessed.
Results
Corneal anesthesia was achieved more rapidly in groups D and R than group C ( < 0.01). Akinesia was achieved more rapidly in the group R than both group D and group C. Akinesia was achieved more rapidly in group D than the control group. Intraocular Pressure was significantly lower in group D compared to both the control group and group R. Ramsay sedation score was significantly higher in group D compared to both the control group and D. Patient and surgeon satisfaction was significantly higher in group R and D compared to the control group.
Conclusion
Adding 5 mg rocuronium to local anesthetic mixture provides more rapid onset of corneal and globe akinesia than 50 μg dexmedetomidine. Adding dexmedetomidine decreases IOP and provides sedation.