Definition: Local skin pressure or friction and shear force for a long time, the pressure on the site of blood circulation disorders and cause local skin and subcutaneous tissue ischemia, necrosis.
Mechanism of occurrence: persistent compression, capillary occlusion when the skin is pressed to a certain degree, local tissue is blocked by blood and metabolic disorders and small vessel thrombosis and secondary tissue necrosis.
Preferred sites
1, the paralyzed area of spinal cord injury, the bony prominence.
2.Sacrococcygeal region, greater trochanter, sciatic tuberosity, heel bone, scapula, posterior occipital region
3, thoracic 4 above the high injury, because the trunk support is low, the more superior the injury the easier to take the pelvis posterior tilt sitting position, so focus on the posterior sciatic.
4. The sacrococcygeal region is most likely to occur during bed rest, while the sciatic tuberosity region is the most likely to occur after riding a wheelchair, and the areas prone to occur differ depending on the wheelchair.
Types of pressure sores.
(a) Typology
1. Ulcer type: Pressure sores involve the superficial layer of the skin and gradually develop deeper, resulting in tissue necrosis and ulceration.
2. Bursitis type: It mainly occurs in the bursal area of the sciatic tuberosity. The early stage is local congestion and swelling, and yellow or blood-colored fluid can be drawn out, manifesting as bursitis. The skin surface is not obviously ulcerated in the early stage, but the deep subcutaneous tissue necrosis is more extensive and the internal cavity is very large, which is also called “closed pressure sore”. This type of pressure sore can form sinus tracts, and poor drainage can be combined with serious infection.
3. Turtle crack type: This pressure sore is near the anus, easily contaminated, turtle cracked, deeper, and the traumas are in contact with each other, easily combined with purulent dermatitis, and is a particularly difficult pressure sore to treat.
(I) Grading
Grade Ⅰ: There is non-resolving erythema, but the skin is intact.
Grade II: The skin is partially broken, involving the epidermis or dermis, with locally visible blisters, shallow depressions or abrasions.
Grade III: The skin is damaged up to the fascial layer with subcutaneous tissue necrosis and localized deeper wounds on the skin.
Grade IV: The whole skin is damaged deep to the muscular layer and bone, and there is a large amount of necrosis of the involved tissues.
Treatment of pressure sores
The first step in the treatment of pressure sores is to identify and remove the cause of the pressure sore. The principles of treatment are systemic and local prevention and management, especially systemic management is very important.
(i) Systemic treatment
This includes improving systemic conditions such as anemia and hypoproteinemia, and treating urinary tract infections. Antibiotic therapy should be given only if there is a systemic infection or if there is local cellulitis in the pressure ulcer. Antibiotic treatment should be combined with surgical debridement for soft tissue infection or osteotomy for osteomyelitis. As serum zinc is significantly lower in patients with spinal cord injury, zinc sulfate should be given internally, oral vitamin C can promote collagen synthesis, and hyperbaric oxygen therapy.
(B) local treatment: in principle, decompression until cure
1. Trauma dressing change: No or less topical drugs are used locally, and it is important to keep the trauma surface clean. Dressings should be changed each time the trauma is cleaned, and foreign bodies, local residual drugs, dressings, trauma exudates and metabolic wastes should be removed from the trauma. Necrotic tissue, if any, should also be removed. The number of dressing changes should be decided according to the amount of exudate.
2.Anti-infection: The main method to control infection is to strengthen local dressing change, if necessary, 2% boric acid solution, 3% hydrogen peroxide solution to rinse the wound, according to the systemic condition and bacterial culture results, you can consider the systemic use of sensitive antibiotics.
3.Physical treatment of trauma: ultraviolet light, ultrasound, infrared, microwave ultra-short wave, etc.
4.Surgical treatment: Although grade Ⅲ Ⅳ pressure sores can be cured by non-surgical treatment, it takes a long time, so surgical treatment should be taken for those who do not heal by long-term non-surgical treatment, have aging trauma granulation, have scar tissue formation at the edges, and have combined bone and joint infection or deep sinus tract formation.
Prevention of pressure sores
(I) Local management
1.Remove local compression
2.Local insulation and massage
3.Keep the skin clean and dry
4. Educate patients and their families about pressure sore prevention, instruct them to learn how to manage their own skin, and learn to use mirrors for self-observation.
(II) Systemic management
1. Strengthen nutrition to prevent anemia and hypoproteinemia
2. Leave the bed, perform active functional training, and encourage exercise, which helps prevent pressure sores.
3.Bathing and showering frequently to improve blood circulation throughout the body.
4.Control muscle spasm
5.Prevent occasional accidents, such as smoking, cooking, hot water, etc., from damaging the skin.