Purpose: To determine the microbial contamination of the irrigating fluids at the time of phacoemulsification after the use of topical povidone-iodine and antibiotics prophylaxis.
Methods: A total of 119 patients undergoing cataract surgery were enrolled in this prospective study. All patients received 5 mg/mL levofloxacin starting from the day prior to surgery and topical and 5% povidone-iodine drops starting from 30 minutes before the surgery. At the end of each surgery, 2 samples of drainage liquids were sterilely collected from the drainage bags (DBL) and from the peristaltic pump single-cassettes (PCL) of the phacoemulsification machine. Search for aerobic and anaerobic bacteria and fungi was performed.
Results: Seventy-five patients (31.5%) revealed a growth of at least one microbial species (53 DBL and 22 PCL, 44.5% vs 18.5%; p<0.001). Sixty-six patients (55.5%) had at least one positive intraoperative solution. Overall, 111 microbial strains were collected: 82 (74%) Gram-positive bacteria, 20 (18%) fungi, and 9 (8%) Gram-negative bacteria. Thirteen staphylococcal isolates from PCL, compared with 52 out of DBL (11% vs 43.7%, p<0.001), fungi were essentially isolated from PCL. No significant correlation was found between microbial isolation and risk factors. No postsurgical infective complication occurred in the follow-up.
Conclusions: Evaluation of intraoperative fluids can provide evidence on sources or vehicles of postsurgical infections. Antibiotic prophylaxis and topical povidone-iodine can significantly contribute to minimize the risk of endophthalmitis.