A Multi-layered Prophylactic Dressing Substantially Alleviates Facial Tissue Loads in Prone-position Surgeries

Background: Prone positioning is typically used where surgical access to the posterior head and spine is required, but this is known to involve a risk for facial pressure ulcers. In this work, we aimed at evaluating facial tissue exposures to mechanical loads during a prone surgical position, with and without multi-layered dressings applied as tissue protectors at primary face-support contact areas.

Methods: We employed a three-dimensional anatomically-realistic computational adult head model to which 5-layer bordered foam dressings had been applied, at the forehead and chin. We simulated prone positioning and calculated tissue stresses and strain energy densities (SEDs, a measure of the mechanical energy delivered to tissues) using the finite element method. The model has been validated against interface pressure measurements at the aforementioned facial sites (N=3 healthy subjects). We determined and compared effective stresses and SEDs at the forehead and chin tissues when dressings had been applied, versus a case where they had not been applied.

Results: Application of the 5-layer border foam dressings at the forehead and chin substantially alleviated exposures of facial skin and subdermal tissues to stresses and SEDs compared to the no-dressing case. Specifically, effective stresses at the chin tissues protected by this dressing were approximately halved with respect to values where no chin dressing was present.

Conclusion: Computer modeling revealed considerable biomechanical effectiveness in applying 5-layer bordered foam dressings to facial areas of patients undergoing surgery in a prone position.