Objective: To determine the etiology of Pseudomonas aeruginosa surgical-site infections following cardiac surgery.
Setting: University teaching hospital.
Patients: Those with wound cultures that grew P. aeruginosa after cardiac surgery performed from 1999 to 2001.
Methods: Medical records and operating room (OR) records of patients with P. aeruginosa cardiac surgical-site infections from 1999 to 2001 were reviewed. Healthcare workers involved with two or more cases were interviewed and examined. Specimens for environmental cultures were obtained from the ORs and cardiac surgical equipment. Cardiac surgery cases were observed and postoperative care and the cleaning of surgical instruments were investigated. OR air handling system records during the epidemic period were reviewed. Molecular fingerprinting of available P. aeruginosa isolates from infected patients and a healthcare worker was done.
Results: There were five P. aeruginosa cardiac surgical-site infections from January to August 2001, compared with no such infections from 1999 to 2000. All were adult patients. One cardiac surgeon with onychomycosis operated on all five cases. He did not routinely double glove. The involved fingernail grew P. aeruginosa. Three P. aeruginosa patient isolates were available for pulsed-field gel electrophoresis; two were identical to the isolate from the involved surgeon's onychomycotic nail. No environmental OR cultures grew P. aeruginosa. The surgeon's culture-positive nail was completely removed. There have been no P. aeruginosa surgical-site infections among cardiac surgery patients since this intervention.
Conclusion: At least two cases of a cluster of P. aeruginosa surgical-site infections resulted from colonization of a cardiac surgeon's onychomycotic nail.