Pressure Injury and Skin Care

A pressure injury (pressure ulcer) is localized damage to the skin and underlying soft tissue, usually over a bony prominence, resulting from sustained pressure or pressure combined with shear. In older and immobile adults it is a common, multifactorial geriatric syndrome that reflects the interaction of mechanical loading with impaired mobility, poor perfusion, malnutrition, moisture, and age-related skin fragility. Because most pressure injuries are considered preventable, risk assessment and skin protection are central to their study.

Definition

A pressure injury is localized damage to the skin and/or underlying soft tissue, usually over a bony prominence or related to a medical device, caused by intense or prolonged pressure or pressure in combination with shear, and graded by stage according to the depth and extent of tissue damage.

Scope

This topic covers how pressure injuries form and are staged, the mechanical and host factors that combine to produce them, the rationale for structured risk assessment, and the place of these injuries among geriatric syndromes. It is a reference and educational entry and does not provide wound-care protocols, dressing selection, or treatment instructions.

Core questions

• How does sustained pressure and shear produce tissue damage, and how are pressure injuries staged?
• Which host and mechanical factors combine to make older, immobile adults susceptible?
• Why is structured risk assessment central to pressure injury as a syndrome?
• What makes pressure injury a largely preventable geriatric syndrome?

Key concepts

• Pressure, shear, and friction as mechanical contributors
• Bony prominences and tissue tolerance
• Immobility and impaired sensory perception
• Malnutrition and impaired perfusion
• Moisture-associated skin damage
• Staging of pressure injuries
• Structured risk assessment

Mechanisms

Pressure injuries form when soft tissue between a bony prominence and an external surface is loaded for long enough to impair local blood flow, producing ischaemia, and, with shear, distortion of vessels and tissue planes. Whether a given load causes injury depends on tissue tolerance, which is reduced by impaired perfusion, malnutrition, moisture, advanced age, and sensory loss that removes the prompt to reposition. The damage often begins in deeper tissue and is staged by the depth and extent of injury. The syndrome is multifactorial because mechanical loading and several host vulnerabilities must coincide, which is why immobile, frail, and undernourished older adults are most affected.

Clinical relevance

Pressure injuries cause pain, infection, prolonged recovery, and substantial burden, and their occurrence is widely used as an indicator of care quality. This entry explains how pressure injuries are conceptualized, staged, and risk-assessed and how the preventive evidence is organized; it is educational and not a basis for individual assessment or treatment.

Epidemiology

Pressure injuries are most frequent among immobile, acutely ill, and frail older adults, with higher occurrence in intensive care, long-term care, and the perioperative setting. Reported prevalence and incidence vary widely by population and setting, but risk rises with immobility, malnutrition, and reduced tissue perfusion.

Evidence & guidelines

Systematic-review evidence on prevention (Reddy and colleagues, 2006) and clinical practice guidelines from the American College of Physicians on risk assessment and prevention (Qaseem and colleagues, 2015) and on treatment (Qaseem and colleagues, 2015) summarize the evidence base. These sources frame current understanding and are not individualized advice here.

History

Pressure sores have been recognized for centuries, but the modern reframing treats them less as inevitable consequences of severe illness and more as largely preventable events driven by identifiable mechanical and host factors. Standardized staging systems and structured risk-assessment tools, together with systematic reviews and clinical practice guidelines, established pressure injury as a measurable target for prevention and a marker of care quality.

Debates

Are all pressure injuries preventable?

While most pressure injuries are considered avoidable with appropriate risk reduction, there is debate about whether a subset is unavoidable in severely ill or dying patients despite optimal care, with implications for how the condition is used as a quality indicator.

Key figures

• Madhuri Reddy
• Amir Qaseem
• Paula A. Rochon

Seminal works

• reddy-2006
• qaseem-2015-risk
• qaseem-2015-treatment

Frequently asked questions

What causes a pressure injury?

Sustained pressure, often combined with shear, over a bony prominence reduces local blood flow and damages skin and underlying tissue; the risk rises when factors such as immobility, malnutrition, moisture, and poor perfusion reduce the tissue's tolerance to that load.

Why is pressure injury considered a geriatric syndrome?

Because it typically results not from a single cause but from mechanical loading combined with several host vulnerabilities — immobility, frailty, malnutrition, and skin fragility — that are common in older adults and act together.