Effect of combining conjunctival fornix irrigation with lid scrubs as a method of pre-operative preparation in cataract surgery-

Abstract

Background: Endopthalmitis following intraocular surgery, although rare (0.1%) could cause visual loss or loss of the eye. In most of the cases of post-operative endophthalmitis follow"cataract surgery, the source of infection has been demonstrated to be the flora on the ocular adnexae. Povidone iodine 5% (PI) has been shown to reduce the conjunctiva and lid flora load. The method of PI application has also been shown to have a direct bearing in the reduction of adnexae flora. Some surgeons prefer to clean the eye lid alone while others combine lid cleaning and irrigation of the fornices, but there is no data to support either preference. Objective: To determine the pre operative efficacy of 5% PIon the conjunctival flora when used in different ways in the preparation of patients for cataract surgery. The indices used were organisms cultured from the lower fornices pre and post intervention. Methodology: This was a randomized controlled trial. A total of a 100 patients who were to undergo cataract surgery were randomly allocated to two arms of fifty patients each. 92 patients were analyzed. 49 (53.30/0)were male while 43 (46.7%) were female (p value 0.531). The age range was 7- 88years. The pre intervention samples were taken from the lid margin and fornix using sterile cotton tipped applicator and inoculation done directly. In the intervention group, 5% povidone iodine was used both on the lid and for irrigation of the fornix. In the control group, only the lid margin was cleaned. The post intervention sample was taken after 2 minutes. Samples were delivered to the laboratory within 3 hours. Incubation for aerobic and anaerobic organisms was done for 24 hours. If no growth obtained, re-incubation was done for further 24 hours up to 72 hours. The colonies were counted manually and identification done appropriately then pre and post intervention colonies were compared. Results: Before intervention, organisms were obtained in 38(82.6%) and 27(58.7%) eyes from the lid and conjunctiva respectively while lid plus fornix irrigation, the positive yield was 42(91.3%) from the lid and conjunctiva 34(73.9%). Heavy growth was noted on the lids. The post intervention positive cultures were 13(65.7% drop) and 14(48.1% drop) on the lid and conjunctiva respectively on the method of lid cleaning only. On the lid plus forinx irrigation the positive cultures which persisted were 13(69% drop) and 5(85.3% drop) on the lid and conjunctiva respectively and same organism persisted. Comparing the conjunctiva cultures, pre and post intervention, the lid cleaning combined with fornix irrigation showed a greater drop in positive culture compared to the lid cleaning method only. Odd ratio of 3.6(1.1- 12.9) 95% CI. Conclusion: lid cleaning combined with fornix irrigation is more effective in decreasing the number of conjunctiva bacteria than the lid cleaning only method.