Blanching of the skin in response to light finger point-pressure being applied to an area of reactive hyperaemia, indicating that the microcirculation is intact.

The point at which pressure on the capillary exceeds blood pressure and the structural strength of the vessel and causes capillary collapse.

Systematically developed statements about care for specific clinical conditions that are based on the best available scientific evidence.

Can be used to quantify the magnitude and direction of a relation. Scores range from -1.00 to +1.00. The closer to -1.00 or +1.00 the greater the reliability of the tool.

Non-specific redness of the skin which may be localised or general in nature. It may be associated with cellulitis, infection, prolonged pressure or reactive hyperaemia.

Dead, dry, thickened, black tissue.

A force created by two contact surfaces moving across one another.

New tissue formed during wound repair consisting of connective tissue and new blood vessels.

Persistent redness when light finger point-pressure is applied to an area of reactive hyperaemia, indicating a disruption to the microcirculation. In lightly pigment in individuals this would be classified as a Stage 1 PU.

The forces created by non-permeating protein molecules within plasma that results in osmosis of water molecules from interstitial fluid into the capillary.

Percentage of occasions in which different people using the same instrument obtain the same result.

Percentage of those at risk who actually develop the condition.

A perpendicular load or force exerted on a unit of area.

Support surfaces that reduce pressure at the surface interface below that found within the basic hospital mattress.

Any lesion caused by unrelieved pressure resulting in damage of underlying tissue.

The number of existing cases of a particular disease or condition in a given population at a designated time.

The number of people with a disease or condition in a given population within a defined time period.

The number of people with a disease or condition in a given population at a specific point in time.

Observable pressure related alteration of intact skin whose indicators as compared to the adjacent or opposite area of the body may include changes in one or more of the following: skin temperature, tissue consistency, and/or sensation.

Partial thickness skin loss involving epidermis and/or dermis. The ulcer is superficial and presents clinically as an abrasion, blister or shallow crater.

Full thickness skin loss involving damage or necrosis of subcutaneous tissue that may extend down to but not through underlying fascia. The ulcer presents clinically as a deep crater with or without undermining of adjacent tissue.

Full thickness skin loss with extensive destruction, tissue necrosis or damage to muscle, bone, or supporting structures. Undermining and sinus tracts may be present.

A normal compensatory mechanism following an episode of reduced perfusion from localised pressure. Relief of this pressure results in a sudden increase in blood flow to the affected tissue.

The degree to which results obtained by a measurement procedure can be replicated.

An aspect of a person's condition, lifestyle or environment which increases the probability of occurrence of a disease. In this case any factor which exposes the skin to excessive pressure, or diminishes its tolerance to pressure.

The accuracy in predicting those who develop the condition.

A parallel load forcing the skeleton to slide forward against a resistance created between the skin and its contact surface. The epidermis and dermis remain relatively anchored to the contact surface while the deep fascia moves with the skeleton. The blood vessels between the dermis and deep fascia may be distorted resulting in thrombosis and capillary occlusion.

The accuracy in predicting those who do not develop the condition.

The pressure applied to the epidermis by the surface that is supporting it.

Tissue destruction which occurs below the level of visible wound bed. The tunnel may extend perpendicularly or obliquely to the visible wound bed.

Area of tissue destruction extending in a parallel plane under the intact skin at the wound margins.

The degree to which a result (of measurement or study) is likely to be true and free of bias (systematic errors).