Efficacy and Safety of Subtenon's and PeribulbarAnaesthesia in Manual Small Incision Cataract Surgery

Objectives: A single blinded prospective and randomized trial was carried out in our institute to evaluate efficacy and safety of subtenon's anaesthesia compared to peribulbar in manual small incision cataract surgery. Methods: This study was conducted in the Department of Ophthalmology, R L Jalappa Hospital and Research Centre, Tamaka, Kolar attached to Sri Devaraj Urs Medical College between January 2008 and June 2011. A total of 500 patients attending eye camps, who underwent Manual Small Incision Cataract Surgery (MSICS) with rigid Polymethyl Methacrylate (PMMA), Intra Ocular Lens (IOL) implantation were included in this study. Patients were randomly assigned to subtenon's group (Group A, n=250) who received 2.5ml of lidocaine (2%) with adrenaline in subtenon's route in inferonasal quadrant after dissecting conjunctiva and peribulbar group (Group B, n=250), who received 6 ml of local anaesthetic (equal quantitie s of 2% xylocaine and 0.5% bupivacaine) in peribulbar r egion. All surgeries were performed by the same surgeon. Results: Pain scores for administration of anaesthetic were significantly lower (P<0.001**) for subtenon's (mean=1.4) compared to peribulbar (mean=2.4). Peroperative pain scores were lower for subtenon's (mean=0.452) than peribulbar (mean= 1.16). Subtenon's produced good akinesia comparable to peribulbar. Subconjunctival haemorrhage (58.4%), chemosis (28%) were commonly noted in subtenon's while ptosis(5 cases) was noted in peribulbar. Moreover less anaesthetic solution and shorter interval from administration to surgery was required in subtenon's. Conclusion: Subtenon's is a better alternative to peribulbar in manual small incision cataract surgery