Prevention of pressure-induced deep tissue injury using intermittent electrical stimulation

Abstract

Pressure ulcers develop due to morphological and biochemical changes triggered by the combined effects of mechanical deformation, ischemia, and reperfusion that occur during extended periods of immobility. The goal of this study was to test the effectiveness of a novel electrical stimulation technique in the prevention of deep tissue injury (DTI). We propose that contractions elicited by intermittent electrical stimulation (IES) in muscles subjected to constant pressure would induce periodic relief in internal pressure; additionally, each contraction would also restore blood flow to the tissue. The application of constant pressure to the quadriceps muscles of rats generated a DTI that affected 60 +/- 15% of the compressed muscle as assessed by magnetic resonance imaging. In contrast, in the groups of rats that received IES at 10- and 5-min intervals, DTI of the muscle was limited to 16 +/- 16 and 25 +/- 13%, respectively. Injury to the muscle was corroborated by histology. In an experiment with a human volunteer, compression of the buttocks reduced the oxygenation level of the muscles by approximately 4%; after IES, oxygenation levels increased by approximately 6% beyond baseline. Concurrently, the surface pressure profiles of the loaded muscles were redistributed and the high-pressure points were reduced during each IES-induced contraction. The results of this study indicate that IES significantly reduces the amount of DTI by increasing the oxygen available to the tissue and by modifying the pressure profiles of the loaded muscles. This presents a promising technique for the prevention of pressure ulcers in immobilized and/or insensate individuals.

Effects of electrical stimulation-induced gluteal versus gluteal and hamstring muscles activation on sitting pressure distribution in persons with a spinal cord injury

“…Muscle contractions induced by electrical stimulation (ES) might help prevent PUs as they improve both the intrinsic risk factors for developing PUs, because ES may reduce atrophy, 5 improve blood flow and oxygenation, 6,7 and sitting pressure distribution as it redistributes pressure away from the IT area. 8 Levine et al [6][7][8] found that surface ES of the gluteal (g) muscles produces a sizeable pressure reduction below the ITs.…”

Effects of Intermittent Electrical Stimulation on Superficial Pressure, Tissue Oxygenation, and Discomfort Levels for the Prevention of Deep Tissue Injury

“…53 In this approach, electrical stimulation is applied for a short duration (on the order of seconds) with several minutes of recovery between stimulations. The muscle contractions produced by the intermittent bursts of stimulation mimic the natural repositioning movements subconsciously performed by able-bodied individuals in response to discomfort while sitting.…”

Gluteal blood flow and oxygenation during electrical stimulation-induced muscle activation versus pressure relief movements in wheelchair users with a spinal cord injury

“…Solis et al found that superficial ES delivered every 10 min is sufficient to greatly reduce the extent of damage in the deep tissue exposed to constant external pressure. 19,20 When the external load decreases, the internal load decreases as well, but more insight into the relationship between IT pressure and deep tissue injury is needed to provide information on the validity of external interface pressure measurements.…”