Enhanced healing of diabetic foot ulcers using local heat and electrical stimulation for 30 min three times per week

Abstract

Background: Electrical stimulation (ES) with heating is effective in healing chronic wounds. However, it this effect due to ES alone or both heating and ES? The aim of the present study was to deduce the individual roles of heat and ES in the healing of chronic wounds. Methods: The study was performed on 20 patients (mean age 48.4 ± 14.6 years) with non‐healing diabetic foot ulcers (mean duration 38.9 ± 23.7 months) who received local dry heat (37°C; n = 10) or local dry heat + ES (n = 10) three times a week for 4 weeks. Patients were given ES using biphasic sine wave stimulation (30 Hz, pulse width 250 μs, current approximately 20 mA). Results: Skin blood flow in and around the wound was measured with a laser Doppler flow imager. In the ES + heat group, the average wound area and volume decreased significantly by 68.4 ± 28.6% and 69.3 ± 27.1%, respectively (both P < 0.05), over the 1‐month period. During the average session, blood flow increased to 102.3 ± 25.3% with local heat and to 152.3 ± 23.4% with ES + heat. In the group receiving treatment with local heat only, wounds that had not healed for at least 2 months showed 30.1 ± 22.6% healing (i.e. a decrease in wound area) after 1 month. Although this level of healing was significant, it was less than that observed in the ES + heat group (P < 0.05). Conclusions: Local dry heat and ES work well together to heal chronic diabetic foot wounds; however, local heat would appear to be a relevant part of this therapy because ES alone has produced little healing in previous studies.

Effect of low-intensity direct current on expression of vascular endothelial growth factor and nitric oxide in diabetic foot ulcers

“…The use of low-intensity ES can be effective in promoting wound closure by mimicking the internal bioelectric system within the wound site. There are some reports that ES promotes blood perfusion and wound closure in diabetic patients [30][31][32]. The results of the present study coincide with previous studies.…”

“…Despite the strong evidence supporting the useful effects of ES for managing chronic wounds [29][30][31][32], the mechanisms of these effects are not yet fully understood. VEGF, as an important angiogenic factor, and NO, as a vasodilator, play a potent role in the formation of new vessels (angiogenesis) in the wound healing process [8][9][10][11]17].…”

Electrical Stimulation Therapy and Wound Healing: Where Are We Now?

“…18 This study used biphasic symmetrical pulsed current with low-current flow, 20 mA) delivered using three electrodes (one active and two reference). However, this study has significant shortcomings, in the small sample size (n = 10 in each group), the short follow-up period (1 month), and the lack of an ES alone control.…”

Does physical therapy and rehabilitation improve outcomes for diabetic foot ulcers?

“…Studies in the literature used different protocols of electrical stimulation for diabetic foot ulcers since. In two, treatment with electrical stimulation was compared to sham treatment [45,46] while in another two studies electrical stimulation was compared to infrared heat lamp [32,41] . Another study compared electrical stimulation to two different control groups, one receiving electrical current at a very low dose (4-mA intensity) and the other not receiving electrical stimulation [47] .…”

“…Electrical stimulation may also stimulate the migration of various wound-modifying cells including keratinocytes, fibroblasts, macrophages, and neutrophils via various signaling mechanisms [40] . Electrical stimulation is typically administered at 30-Hz frequency, at a pulse every 250 microseconds, and 20-milliampere current, using 5 cm × 5 cm disposable carbonized electrodes, for 30 min three times weekly [41] . This treatment modality should not be used in patients with a cardiac pacemaker [39] .…”