Bacterial skin contamination and bacterial recolonization, after surgical preparation, in foot operations and prevalence of postoperative early wound infection: A prospective study

Effective presurgical preparation is an important step in limiting surgical wound contamination and prevention of surgical site infection. The purpose of this study is to evaluate bacterial skin contamination after surgical skin preparation in foot surgery prior to surgery and at the end of surgery, in order to determine if current techniques are satisfactory in eliminating harmful pathogens, and to compare the results of the cultures obtained pre- and postoperatively with infection rate. Twenty consecutive patients scheduled for hallux valgus procedures were studied. Each lower extremity was prepared in the regular method with a two-step technique, septal scrub (chlorhexidine gluconate 4%) followed by a alcohol chlorhexidine antiseptic solution. After preparation and draping, cultures were obtained at three locations: the hallux nailfold, first, second, third and fourth web spaces, and the anterior ankle (control). Prior to surgery, positive cultures were obtained from 80% of hallux nailfolds and 5% of web spaces. At the end of surgery, positive cultures were obtained from 80% of hallux nailfolds and 25% of web spaces. None of the control sites had positive culture. Five percent of all cases developed postoperative infection. Based on the findings of the current study, presurgical skin preparation with a two-step septal scrub (chlorhexidine gluconate 4%) followed by a alcohol chlorhexidine antiseptic solution is not sufficient in eliminating pathogens in foot and ankle surgery. No statistical correlation was found between the results of the cultures obtained pre- or postoperatively with postoperative infection rate. The unique environment of the foot and its resident organisms probably plays a role in the higher infection rates associated with surgery of the foot. Better methods of preparing the surgical site should be searched for.