Release of sodium pyruvate from sacral prophylactic dressings: A computational model

The use of sacral dressings for pressure ulcer prevention is growing rapidly. In addition to their passive biomechanical role in pressure and shear reduction, in the near future, prophylactic dressings may also provide active tissue protection by releasing preventive agents or drugs into skin and deeper tissues. We investigated delivery of sodium pyruvate (NaPy) from an active dressing to potentially protect the sacral skin and underlying tissues in addition. We used four finite element model variants describing different skin roughness levels to determine time profiles of NaPy diffusion from the dressing into the skin layers. The NaPy concentrations for the different modelled cases stabilised after 1 to 6.5 hours from the time of application of the dressings, at 1% to 3% of the NaPy concentration in the dressing reservoir, which is considered potent. We conclude that prophylactic sacral dressings have the potential to deliver NaPy into skin and subdermally, to potentially increase soft tissue tolerance to sustained bodyweight-caused cell and tissue deformations. The time durations to achieve the steady-state potent NaPy dermal concentrations are clinically feasible, for example, for preparation of patients for surgery or for use in intensive care units.