Polarized currents inhibit in vitro growth of bacteria colonizing cutaneous ulcers

Area of Science:

• Biomedical Engineering
• Infectious Diseases
• Wound Healing

Background:

• Pressure ulcer infections are frequently caused by Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli.
• Polarized current therapy is being investigated as a method to control bacterial proliferation in wound environments.

Purpose of the Study:

• To evaluate the efficacy of fixed diphasic - Bernard (FD-B) and high voltage monophasic pulsed (HVMP) currents in inhibiting the growth of S. aureus, P. aeruginosa, and E. coli.
• To assess the impact of these currents on bacterial colony-forming units (CFU) in vitro.

Main Methods:

• Bacterial strains (S. aureus, P. aeruginosa, E. coli) were cultured and suspended in saline.
• Cultures were exposed to FD-B current (3-9 mA, 100 Hz, 15-30 min) and HVMP current (32-95 V, 100 Hz, 30-60 min).
• Bacterial viability was quantified by CFU counts post-stimulation; pH and temperature were monitored.

Main Results:

• Both FD-B and HVMP currents significantly reduced bacterial CFU counts.
• FD-B current exhibited a more pronounced inhibitory effect on bacterial proliferation compared to HVMP.
• Current application maintained stable temperature, with pH changes observed at the electrodes (acidic at positive, alkaline at negative).

Conclusions:

• In vitro application of FD-B and HVMP currents effectively inhibits the proliferation of key wound pathogens.
• These polarized current modalities show potential as adjunctive therapies for enhancing wound healing by controlling bacterial load.