Comparison of normal saline with tap water for wound irrigation

This study compared irrigation with tap water versus saline for removing bacteria from simple skin lacerations. The study was conducted in an animal model with a randomized, nonblinded crossover design using 10 500-g laboratory rats. Two full-thickness skin lacerations were made on each animal and inoculated with standardized concentrations of Staphylococcus aureus broth. Tissue specimens were removed before and after irrigation with 250 cc of either normal saline from a sterile syringe or water from a faucet. Bacterial counts were determined for each specimen and compared before and after irrigation. There was a mean reduction in bacterial counts of 81.6% with saline and 65.3% with tap water (P = .34). One tap water specimen had markedly aberrant bacterial counts compared with others. Excluding this specimen, the mean reduction for tap water was 80.2%. In this model, reduction in bacterial contamination of simple lacerations was not different comparing tap water with normal saline as an irrigant.