The Effect of Different Wound Irrigation Solutions on Reduction of Bacterial Bioburden in Real World Data

Aim: The influence of different irrigation solutions by using with a wet-to-moist cleansing on the reduction of sessile, non-planktonic bacteria has not been investigated so far. In this study, the antibacterial effect of different irrigation solutions, during a 20-minute wet-to-moist cleansing, has been evaluated in chronic wounds.

Method: This study was designed as a prospective cohort study with 12 study arms and was conducted during a five-year period of time. Patients with chronic wounds (> three months) were recruited. Quantitative wound swabs were obtained before and after a 20-minute, wet-to-moist cleansing, using different wound irrigation solutions. Sterile 0.9% saline solution was used as control.

Results / Discussion: 260 patients with 299 chronic wounds were eligible for analysis. Staphylococcus aureus was the most common recovered (25.5%) microorganism, of which 8% were methicillin-resistant Staphylococcus aureus (MRSA) strains. Although 0.9% saline supported cleansing of the wound bed, it did not significantly reduce the bacterial burden. The highest reduction of bacterial burden was achieved with an aqueous solution containing betaine, zinc, iron and the preservative polyhexamethylene biguanide (polihexanide; ln RF=3.72), followed by a 3% saline solution containing 0.2% sodium hypochlorite (ln RF=3.40).
Except a 0.9% NaCl solution as well as a 0.1% PHMB and undecylenamidopropyl-betaine solution and aqueous lithium-magnesium-sodium-silicate oxygen, all investigated solutions achieved measurable and significant bacterial reduction over 20 minutes’ application time.

Conclusion: If a reduction of bacterial burden is warranted, wound irrigation solutions containing a combination of hypochlorite/hypochlorous acid or antimicrobials/antiseptics such as polihexanide, octenidine or povidone-iodine, should be considered. According to the considerable number of products containing sodium hypochlorite/hypochlorous acid, a selection has to be made due to the different preservative effects of different presentation forms.