Pain Following the Use of Anesthesia Formulation Among Individuals Undergoing Cataract Surgery: A Randomized Controlled Trial

In ocular tissue, arachidonic acid is metabolized by cyclooxygenase to prostaglandins which are the most important lipid derived mediators of inflammation. Presently nonsteroidal anti-inflammatory drugs (NSAIDs) which are cyclooxygenase (COX) inhibitors are being used for the treatment of inflammatory disorders. NSAIDs used in ophthalmology, topically, are salicylic-, indole acetic-, aryl acetic-, aryl propionic- and enolic acid derivatives. NSAIDs are weak acids with pKa mostly between 3.5 and 4.5, and are poorly soluble in water. Aqueous ophthalmic solutions of NSAIDs have been made using sodium, potassium, tromethamine and lysine salts or complexing with cyclodextrins/solubilizer. Ocular penetration of NSAID demands an acidic ophthalmic solution where cyclodextrin could prevent precipitation of drug and minimize its ocular irritation potential. The incompatibility of NSAID with benzalkonium chloride is avoided by using polysorbate 80, cyclodextrins or tromethamine. Lysine salts and α-tocopheryl polyethylene glycol succinate disrupt corneal integrity, and their use requires caution. Thus a nonirritating ophthalmic solution of NSAID could be formulated by dissolving an appropriate water-soluble salt, in the presence of cyclodextrin or tromethamine (if needed) in mildly acidified purified water (if stability permits) with or without benzalkonium chloride and polyvinyl alcohol. Amide prodrugs met with mixed success due to incomplete intraocular hydrolysis. Suspension and ocular inserts appear irritating to the inflamed eye. Oil drop may be a suitable option for insoluble drugs and ointment may be used for sustained effect. Recent studies showed that the use of colloidal nanoparticle formulations and the potent COX 2 inhibitor bromfenac may enhance NSAID efficacy in eye preparations.

Purpose To evaluate postoperative pain and early recovery in cataract patients. Patients and methods A total of 201 patients who underwent elective first eye cataract extraction surgery were enrolled, and 196 were included in the final analysis. The study design was a single-center, prospective, follow-up study in a tertiary hospital in eastern Finland. Postoperative pain was evaluated with the Brief Pain Inventory at four time points: at baseline, and at 24 hours, 1 week, and 6 weeks postsurgery. Results Postoperative pain was relatively common during the first hours after surgery, as it was reported by 67 (34%) patients. After hospital discharge, the prevalence decreased; at 24 hours, 1 week, and 6 weeks, 18 (10%), 15 (9%) and 12 (7%) patients reported having ocular pain, respectively. Most patients with eye pain reported significant pain, with a score of ≥4 on a pain scale of 0–10, but few had taken analgesics for eye pain. Those who had used analgesics rated the analgesic efficacy of paracetamol and ibuprofen as good or excellent. Other ocular irritation symptoms were common after surgery; as a new postoperative symptom, foreign-body sensation was reported by 40 patients (22%), light sensitivity by 29 (16%), burning by 15 (8%), and itching by 15 (8%). Conclusion Moderate or severe postoperative pain was relatively common after cataract surgery. Thus, all patients undergoing cataract surgery should be provided appropriate counseling on pain and pain management after surgery.