压疮的原因（Causes of pressure sores）.doc

压疮的原因（Causes of pressure sores） Key words: bedsore; etiology; nursing Also called the bedsore bedsore, due to local tissue body prolonged pressure, blood circulation, tissue deficiency causing skin to lose normal function, tissue necrosis caused by skin ulcer, nursing three major complications, once the pressure sore, not only bring pain to the patient, increased economic burden, increasing the workload of the nursing staff but, will aggravate the disease, prolong the time of rehabilitation. In severe cases, it can be life-threatening because of secondary infection [1]. 1 the cause of pressure sores At present, there are 4 main factors that cause pressure sores, that is, pressure, shear force, friction and humidity. The main reason is stress, and is related to the length of duration. Landls found that the capillary pressure of normal skin was 2.7 kPa, Melenna and so on. The capillary pressure was 2.1 to 4.3 kPa using a plethysmography. The changing of up to 4 h under 4.67 kPa pressure or under pressure, even 25.3 kPa up to 1 h will not appear to change, but if the pressure of 9.3 kPa for 2 h cells may cause irreversible changes. This suggests the need for less stress at intervals (2). The shear force is more dangerous than the vertical pressure, and the shear force is increased in the sacrum, such as when the head is supine or the head is raised or tilted. Friction is the mechanical force on the epithelial tissue, can protect the skin keratosis removal of the outer layer, increase the sensitivity of skin pressure ulcers, wrinkles, rough bed debris or move the patient drag, pull, pull, pull all have bigger friction. Dampness is another reason. In a humid environment, the risk of sore pressure increases by 5 times [3]. Incontinence and sweating caused by moist stimulation, resulting in skin maceration and soft, easily wound by shear and friction. Systemic malnutrition, negative nitrogen balance, dry skin and poor elasticity are prone to pressure sores. Inadequate care