Background: The human skin microbiome consists of colonizing and pathogen germs. The umbilical dimple is a humid environment prone to bacterial colonization and growth. In the laparoscopic era, the umbilicus has become the most common site of entrance into the peritoneum. The aim of this study was to describe the characteristics of umbilical microflora before antiseptic skin preparation.
Methods: Descriptive single-center study. A series of patients who underwent laparoscopic/open and elective/urgent abdominal surgery over a 2-month period were included. Patients were admitted the same day or the day before surgery. Before antiseptic skin preparation, microbiological samples were taken from the umbilicus, left upper abdominal quadrant, and nostril. A delayed referral time (>30 minutes) of the skin swabs to the microbiology laboratory was an exclusion criterion.
Results: Overall, 70 patients were included. The median age was 64 years (range 16-89) and a laparoscopic approach was used in 82.8% of cases. The most commonly performed operation was laparoscopic fundoplication for gastroesophageal reflux (25.8%). In the umbilicus, the most frequent colonizing bacteria were coagulase-negative Staphylococcus species and Corynebacterium. Opportunistic pathogens were found in 10 umbilical swabs compared with 8 in the left upper quadrant (14.2% versus 11.4%, p = .800). Overall, 50% of patients with umbilical opportunistic pathogens had a medium/high bacterial load compared with 62.5% in the left upper quadrant (p = .958). No postoperative surgical site infection was recorded in the study sample.
Conclusions: Both the umbilicus and the left upper quadrant appear to be safe entry sites in laparoscopic surgery. Meticulous hygiene of these anatomical areas is strongly recommended before surgery regardless of the type of antiseptic solution and the short-term antibiotic prophylaxis. In-hospital preoperative showers may be unnecessary for well-educated patients.
Keywords: laparoscopy; microflora; surgery; surgical site infection; umbilicus.