Eradication of Wound Biofilms by Electrical Stimulation - Antibiofilm Agents: From Diagnosis to Treatment and Prevention - page 425

population. In this study, 70 mA/cm 2 LIDC was applied for 1 h in order to target the
persister cells.

8 Low-Intensity Direct Current Contraindications

One of the primary problems associated with using DC against biofilms includes the
potential production of toxic compounds at the electrode interface causing collat-
eral tissue damage. Since DC cannot be generated by insulated electrodes, the
production of these toxic derivatives remains a long-term problem (Giladi
et al. 2010 ). Additionally, such currents may stimulate nerve or muscle cells
resulting in pain and muscular contractions in the patient. Due to these inherent
problems, it comes as no surprise that only 10 % of polled physical therapists use
LIDC on a weekly basis (Robinson and Snyder-Mackler 1988 ). Other electrical
stimulation modalities, with HVPC on the top of the list, are utilized by clinicians
and are the subject of research efforts.

9 High-Voltage Pulse Current Background

HVPC devices create pulsed current with maximum capacity ranging from 100 to
250 V. HVPC electricity displays a twin-peaked wave form (Fig. 1B ) and lasts for a
very short time (5-100 s). The electricity generated in HVPC can be either DC

(monophasic) or AC (biphasic), although DC is the primary electrical source
utilized. The idea behind HVPC is that it allows higher voltages to be utilized in
such fast pulses that nerve or other human cells are not excited and damaged. HVPC
was explored in the 1980s following the successful clinical application of LIDC to
wound infections in the early 1970s. The initial popularity of HVPC was linked to
the finding that electrodes from HVPC devices did not cause thermal or chemical
reactions and thus eliminated many of the unwarranted side effects associated with
LIDC (Alon and De Do-minico 1987 ). Pulsed current has been the most frequently
utilized form of ESTHR by physical therapists in the USA, with a reported 2/3 of
the polled therapists utilizing HVPC on a daily basis (Robinson and Snyder-
Mackler 1988 ).

μ

10 High-Voltage Pulse Current Clinical Studies

One of the initial HVPC studies was conducted by Feeder and Kloth in 1988 where
they conducted a single-blinded RCT with 16 patients suffering from Stage IV
decubitus ulcers (Kloth and Feedar 1988 ). The patients were randomly assigned
into a SWC + ESTHR-treated group ( n ¼

9) or a control group only receiving