Evaluation of Pain after Vitrectomy in Patients Receiving Rectal Diclofenac as Pre-emptive Analgesia

Post-operative pain is a frequent complication after surgery which can increase the risk of other post-operation complications and also the duration of hospital stay. In this study, we have tried to assess the effect of rectal diclofenac as pre-emptive analgesia to reduce post-operative pain after ophthalmic surgeries(vitrectomy).Patients and This study was designed and performed as a double-blind clinical trial. The patients who were candidates for vitrectomy in Rasool-e-Akram Hospital were included in the study according to some exclusion and inclusion criteria and divided into two groups of diclofenac and control. In diclofenac group,patients received a single dose of 100mg 2 hours before surgery.The pain scores were assessed in recovery room,4 and 12 hours after vitrectomy using the visual analogue scale(VAS). To compare qualitative and quantitative data of the two groups, provided that normal distribution existed, we used Chi-square test for qualitative variables and t-test for quantitative variables. Also, in order to determine confounding factors exactly and assess the effect of time, multiple regression analysis was used. A total of 97 patients were divided into two groups:51 persons in diclofenac group and 46 persons in the control group. The mean of pain intensity at the 4th hour after surgery in diclofenac group was lower than the control group(p<0.001). Pain intensity at the12th hour after surgery in diclofenac group was 2± 0.6 and in the control group was 3.3±0.8, which was statistically lower in diclofenac group than the control group(p<0.001). Multiple regression analysis revealed that two factors,i.e. increasing age and using diclofenac, were effective in reducing pain(p<0.05). Single dose of rectal diclofenac as pre-emptive analgesia is effective in reducing post-vitrectomy pain.