Why pressure injuries happen
When a person lies or sits in one position for long, the skin and tissue over bony areas, such as the sacrum, heels and hips, are squeezed between bone and mattress. Blood flow drops, and within hours the tissue can start to die. These pressure injuries, also called pressure ulcers or bedsores, are painful, slow to heal and largely preventable. The Braden scale, developed by nurses Barbara Braden and Nancy Bergstrom in 1987, identifies who needs prevention most.
The six subscales
| Subscale | What it measures | Score |
|---|---|---|
| Sensory perception | Ability to feel and report discomfort | 1–4 |
| Moisture | How often the skin is wet from sweat, urine or drainage | 1–4 |
| Activity | Bedfast, chairfast, walks occasionally or frequently | 1–4 |
| Mobility | Ability to change and control body position | 1–4 |
| Nutrition | Usual food intake pattern | 1–4 |
| Friction and shear | Sliding in bed or chair, need for help to move | 1–3 |
The total ranges from 6 to 23. Lower is worse.
Worked example
An older patient recovering from a hip fracture can feel pain but has trouble reporting it (sensory 3), is occasionally damp (moisture 3), sits in a chair most of the day (activity 2), makes slight changes of position alone (mobility 3), eats most meals (nutrition 3) and slides down in the chair from time to time (friction 2). The score is 16: at risk. The lowest subscales, activity and friction, show where to act: a pressure-redistributing cushion, a repositioning schedule and help to sit back without dragging.
Risk levels
- 19 to 23: no particular risk.
- 15 to 18: mild risk.
- 13 to 14: moderate risk.
- 10 to 12: high risk.
- 9 or less: very high risk.
Many facilities start prevention at a score of 18 or less. The score supports, rather than replaces, a nurse’s judgment and a daily look at the skin.
Prevention
- Reposition regularly; every two hours is a common starting point in bed, more often for very high risk.
- Support surfaces: pressure-redistributing mattresses and cushions.
- Offload the heels with a pillow under the calves.
- Manage moisture: clean promptly after incontinence and use barrier creams.
- Nutrition and hydration: protein, calories and fluids; a dietitian for poor intake.
- Avoid friction and shear: lift sheets, keep the head of the bed as low as is safe.
Check the skin daily, especially the sacrum, heels, hips and the back of the head. Redness that does not fade when pressed is an early warning sign.
This calculator is for general information and education. It is not medical advice and does not replace the judgment of a doctor, nurse or pharmacist who knows the full clinical picture.