Optimizing breast pocket irrigation: An in vitro study and clinical implications

Subclinical infections have been implicated in the etiology of capsular con tracture. Intraoperatively, breast pocket irrigation with providone-iodine or other antibiotic solutions has been popularized; however, detrimental ef fects on wound healing for these agents have been reported and their effica cy against common organisms found around breast implants has not been studi ed. The purpose of this study was to compare the in vitro efficacy of seria l dilutions of povidone-iodine and two double antibiotic solutions DAB-1 (g entamicin/polymyxin B) and DAB-2 (gentamicin/cefazolin), against organisms most commonly found around breast implants. In phase I trials, serial dilut ions of povidone-iodine and DAB were combined 1:1 with cultures of five com mon organisms found around implants. In phase II, povidone-iodine was seria lly diluted in DAB-1 rather than saline. In phase III, povidone-iodine was serially diluted with DAB-2. Efficacy for all phases was determined by plat ing the mixture onto agar plates and incubating at 37 degrees C for 48 hour s. Povidone-iodine was 100 percent effective at a dilution of 12.5% against Staphylococcus epidermidis and 25% against Staphylococcus aureus but relat ively ineffective against Escherichia coli and Pseudomonas; DAB-1 was found to be ineffective against S. epidermidis but effective against S. aureus, Propionibacterium acnes, E. coli, and Pseudomonas. In phase II trials, a co ncentration of 12.5% povidone-iodine in DAB was effective at killing all ex perimental bacteria. In phase III trials, 10% povidone-iodine in DAB-2 was effective at killing all bacteria tested. In conclusion, to maximize bacter ial control of common breast implant organisms and to minimize the detrimen tal effects on wound healing, 10% povidone-iodine in gentamycin/cefazolin m ay be used with excellent results and its use clinically may reduce the inc idence of capsular contracture.