For people with stroke, spinal cord injuries, amputation, obesity and other conditions, the development of a pressure ulcer could be the beginning of a downward health spiral that could lead to death. As I was teaching this topic to university students studying Occupational Therapy, the need for community education for care givers became clear. In posting these risk factors I hope to share some basic info that will get caregivers thinking about what they could do to prevent this serious health issue.
Typically these ulcers originate when folks with limited mobility maintain static positions in their wheelchair or bed without relief. Sufficient pressure (either in duration or intensity) can alter blood flow compressing capillaries and depleting the skin and structures beneath of oxygen and essential nutrients. Metabolic wastes accumulate and the vascular and lymphatic systems are unable to evacuate them. As the tissues begin to die and inflammation occurs, infection and subsequently more cells die. The result is a pressure ulcer, defined as "any lesion caused by unrelieved pressure resulting in damage of underlying tissue." 1
Most people think that this breakdown starts at the skin surface, when in fact pressure ulcers typically develop at the subcutaneous level (muscle or bone). As pressure is translated through tissues to the bone the measure of pressure intensity may be significantly higher and the amount of external pressure required to prevent oxygenation is much less over the bone than over muscle. Common areas on the body which are prone to pressure ulcers from sitting are locations with boney prominences such as under the buttocks, the low back, shoulder blades. From lying in bed the heels, ankles, back, shoulders, elbows and hips.
Although healthcare professions are trained to spot the initial signs of pressure ulcer development, they are not with the disabled person day to day and the lack of education provided to caregivers and family is what sends these folks to the hospital with stage 3 or 4 ulcers because risks factors went unknown and undetected. The following are a list of 10 common pressure ulcer risk factors:
1. Perpendicular Pressure - Direct point pressure will ultimately result in compromised circulation and cell death. This is usually the result of inadequate pressure management either in intensity or duration.
2. Parallel Pressure (Shear) - When the body slides across a surface and friction is in effect, usually the result of improper positioning, movement or non-uniform pressure distribution.
3. Moisture - At the body surface can be due to incontinence, perspiration; insufficient drying after bathing which all can create friction and magnify the risk of shear.
4. Friction - Caused by repetitive movements, sliding transfers, spasticity, agitation, over high friction surfaces can result in the damage to superficial skin causing mild burn.
5. Increased Age - With normal aging there is a general atrophy of soft tissue such as fat and muscle, which normally acts as a protective cushioning barrier to external pressure.
6.Decreased Sensory Perception - Due to nervous system impairment impedes the person from receiving cues to change position.
7. Impaired Mobility - A person who is unable to physically reposition themselves.
8. Decreased Mental Status - A person who has an impaired responsiveness to their environment.
9. Circulation Impairment - blood vessels that are structurally compromised are more likely to become occluded due to pressure, shear and resulting tissue ischemia.
10. Poor Nutrition - Decrease nutritional status can result in weight loss and loss of protective soft tissue. Decrease protein intake as well as Vitamin C, impairs collagen formation.
Early signs of pressure ulcers include any areas of redness after exposure to pressure, hardening of the skin, bogginess and increased skin temperature at the suspected area. If caught early worsening of these pressure ulcers can be prevented. Knowing the risk factors and learning about prevention strategies could make the difference in saving someone from the deadly infections that often show up with aggressive pressure ulcers.
For more information on the prevention of pressure ulcers visit http://www.preventpressureulcers.ca
Marnie Courage, OT reg (MB)
1.Bergstrom,N.,Bennett,M.A.,&Carlson,Ce.E. (1994). Clinical practice guideline: Pressure ulcer treatment