Subconjunctiva Bupivacaine as Analgesia in Intravitreal Silicone Oil Removal

The study aimed to investigate the effectivity of bupivacaine 0,5% as post-operative analgesia in intravitreal silicone evacutaion surgery

Approval from Ethical Committee of Faculty of Medicine Universitas Indonesia was acquired prior conducting the study. Subjects were given informed consent before enrolling the study and randomized into two groups. Intravenous (IV) cannule with Ringer Lactate fluid, non-invasive blood pressure monitor, electrocardiogram (ECG) and pulse-oxymetry were set on the subjects in the operation room. Co-induction was done with midazolam 0,05 mg/kg and fentanyl 2 mcg/kg. Induction was done with propofol 1-2 mg/kg, followed by Laryngeal Mask insertion facilitated by atracurium 0,5 mg/kg. Maintenance was done with sevoflurane 1-2 vol%, O2:H2O = 1:2, flow 2 liter/minute. Surgery started. After final stitching, Group 1 received subconjunctival bupivacaine 0,5% 2,5ml in between stitches; Group 2 received subconjunctival NaCl 0,9% in between stitches. Both groups received paracetamol 20 mg/kgBW IV as post-operative analgesics. Hemodynamic, pain degree (using Visual Analog Scale / VAS), and nausea/vomiting incidence, and the time for first requested additional analgesia were recorded. Data was analyzed using SPSS (Statistical Package for Social Scientist), for numerical data using unpaired T-test or Mann-Whitney-U test, for categorical data using Chi-square test or Fischer Exact's Test. Data normality was tested by Kolmogorov-Smirnov test. Significant value is p<0.05.

Bupivacaine 0,5% was given on the subconjunctiva, in between stitches by the surgeon after finishing the last stitches

NaCl 0,9% was given on the subconjunctiva, in between stitches by the surgeon after finishing the last stitches

The time for first requested post-operative additional analgesia was measured in minutes in the morning after the surgery

Inclusion Criteria: Subjects aged 18-60 years old, with ASA physical status I-II and BMI 18,5-30 kg/m2 who were planned to do intravitreal silicone evacuation surgery. Subjects have been explained about the study, have agreed to enroll and have signed the informed consent form Exclusion Criteria: Subjects with history of post-operative chronic pain Subjects with history of pre-operative long term use of analgesic Subjects with history of local anesthetics allergy, pregnant subjects Subjects with ambulation operation Subjects with glaucoma or ocular hypertension Subjects with cognition dysfunction or communication disturbance Subjects with additional surgery other than silicone oil removal Drop Out criteria: Subjects with intraoperative complications (e.g. shock, anaphylactic reaction, seizures, severe respiratory disturbance) Subjects with post-operative intraocular pressure > 22mmHg.

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