Study on immediate postoperative pain following cataract surgery: intraoperative endovenous administration of dipyrone

Abstract Objectives: Evaluate the effect of intraoperative endovenous administration of dipyrone on postoperative pain in patients submitted to phacoemulsification by correlating pain scores with duration of surgery and the amount of cumulative dissipated energy (CDE) delivered to the eye. Methods: The sample consisted of 104 eyes from 52 patients submitted to phacoemulsification under topic anesthesia and sedation. In each patient, one eye was treated intraoperatively with 1g dipyrone. Information was collected on cataract grade/type, duration of surgery and CDE. Postoperative pain was scored on a visual analog scale at 15 min and 24 hours. Results: Between 15 min and 24 hours, pain decreased significantly (p=0.004) among patients not treated with dipyrone, but no change was observed in patients receiving dipyrone. Caratact severity was positively associated with postoperative pain (p=0.046). Conclusion: The absence of a measurable effect of dipyrone on pain scores matched the literature. The decrease in pain scores at 24 hours among patients not treated with dipyrone may be explained by the influence of subjective psychological factors on pain perception. Higher grades of cataract were associated with greater postoperative pain.