The influence of high-voltage electrical stimulation on edema formation after acute injury: a systematic review.

CONTEXT Electrical stimulation is often used to control edema formation after acute injury. However, it is unknown whether its theoretical benefits translate to benefits in clinical practice. OBJECTIVES To systematically review the basic-science literature regarding the effects of high-voltage pulsed stimulation (HVPS) for edema control. EVIDENCE ACQUISITION CINAHL (1982 to February 2010), PubMed (1966 to February 2010), Medline (1966 to February 2010), and SPORTDiscus (1980 to February 2010) databases were searched for relevant studies using the following keywords: edema, electrical stimulation, high-volt electrical stimulation, and combinations of these terms. Reference sections of relevant studies were hand-searched. Included studies investigated HVPS and its effect on acute edema formation and included outcome measures specific to edema. Eleven studies met the inclusion criteria. Methodological quality and level of evidence were assessed for each included study. Effect sizes were calculated for primary edema outcomes. EVIDENCE SYNTHESIS Studies were critiqued by electrical stimulation treatment parameters: mode of stimulation, polarity, frequency, duration of treatment, voltage, intensity, number of treatments, and overall time of treatments. The available evidence indicates that HVPS administered using negative polarity, pulse frequency of 120 pulses/s, and intensity of 90% visual motor contraction may be effective at curbing edema formation. In addition, the evidence suggests that treatment should be administered in either four 30-min treatment sessions (30-min treatment, 30-min rest cycle for 4 h) or a single, continuous180-min session to achieve the edema-suppressing effects. CONCLUSIONS These findings suggest that the basic-science literature provides a general list of treatment parameters that have been shown to successfully manage the formation of edema after acute injury in animal subjects. These treatment parameters may facilitate future research related to the effects of HVPS on edema formation in humans and guide practical clinical use.