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Pressure Ulcers: Cause

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Pressure ulcers are a common problem in the field of nursing, often seen in patients with decreased mobility such as those living with paralysis or the elderly. Colloquially referred to as bedsores, pressure ulcers can occur whenever the body has been set in the same position for too long causing a loss of blood flow to an area. This condition presents a challenge to nursing staff due to the lack of warning signs involved. Patients can often not feel a pressure ulcer developing or are unable to communicate that they are in pain. It falls to the nursing staff to enact protocols aimed at decreasing the incidence of pressure ulcers (Chou et al., 2013).

These guidelines aim to address four main topics regarding nursing care and pressure ulcers: causes, types, treatment options, and prevention. Understanding the causes allows nurses to identify certain warning signs that might indicate a patient is at a high risk for developing a pressure ulcer. The various types allow readers to understand the severity of pressure ulcers and how they develop. Treatment options are reactive measures taken to handle an ulcer once it has begun to develop. These are necessary measures but are not as effective as prevention, which avoids the development of pressure ulcers altogether. It is the goal of any nurse to engage in preventative medicine first, but also to be educated on care should prevention fail (Llano, Bueno, Rodriguez, Bagües, & Hidalgo, 2013).


Nurses must be educated on the causes of pressure ulcers, effective methods to prevent them, and the treatment options for people with pressure ulcers. This effort must be pervasive throughout the nursing field affecting administrators, nurses working directly with patients, and educators. A multifaceted approach utilizing knowledge of nutrition’s effect on bodily tissues, information technology for patient tracking, and supportive technologies for posture must be used to reduce the impact pressure ulcers have in clinical settings.

Cause of Pressure Ulcers

According to an analysis of available data conducted in 2013 by Coleman et al., there is no one indicator that pressure ulcers may be likely to develop in a patient, but rather there is a “complex interplay of factors” which indicate a patient’s risk for developing a pressure ulcer. This is due to the fact that certain underlying physiological mechanisms can cause tissue to be more likely to become ischemic even under the same pressure. Medical conditions such as infection, diabetes, and multiple sclerosis can affect tissue strength and the nervous system’s ability to respond to damage and initiate healing.

Pressure ulcers can be best said to be caused by weight on a certain part of the body for a long enough time that it becomes ischemic and leads to tissue death. This is the underlying mechanism behind all pressure ulcers, however, little more can be correlated with their risk regarding pre-existing medical conditions. Hence, the primary causes of prolonged pressure on an area of the body must be examined, which are an inability to move and a loss of sensation. This section will also discuss elderly patients as they experience both prerequisite conditions for being at risk for pressure ulcers.

Common points of pressure


Inability to Move

According to Bradford (2016), one of the most disturbing facts about the development of pressure ulcers is that many people who have them can feel them developing but cannot do anything to prevent them on their own. People with partial paralysis, loss of motor control, locked-in syndrome, certain cases of morbid obesity, and simply being elderly can inhibit one’s ability to move and can lead to the development of one or more pressure ulcers. For this reason, nurses working with these patients need to be careful to monitor them for early signs of ischemia and to help them shift into different positions periodically.

Loss of Sensation

The second major contributing factor to the formation of pressure ulcers is the loss of sensation, which many patients with nerve damage can experience. Sensation is carried by a different set of axons than motor control, and therefore, the loss of sensation must be treated differently than an inability to move. People will often experience variations in their ability to control their muscles and feel pain and pressure. Hence, no two patients can be treated the same in this regard (Coleman et al., 2013).

Nerve damage can be caused by a number of conditions, many of them already mentioned such as multiple sclerosis and diabetes. The actual pressure of a patient lying in a position can cause nerve damage. So a patient who is heavily sedated may rest long enough in one position to lose sensation in an area to the point that they will not entirely regain the sensation even after coming out of their anesthetized state. For this reason, all preoperative patients can be seen as at risk for developing pressure ulcers. Pressure ulcers can have a cumulative effect on nerve damage, wherein the more damage that occurs to the tissue, the less sensation the patient will have that damage has occurred (Coleman et al., 2013).

Elderly Patients

Elderly patients present a particular challenge in managing pressure ulcers due to the fact that there is often nothing medically wrong with them other than the fact that their bodies are beginning the process of shutting down. There are many variables at play and they can show any level of sensation or motor control often for no clear reason. Additionally, since elderly people have lived the longest, they are the most likely to have been injured, which means that any small nerve damage that may have occurred to them during their lives will now have an amplified effect as their bodies transition into a less functional state (Llano, Bueno, Rodriguez, Bagües, & Hidalgo, 2013).

Due to the constant transitionary nature of aging, elderly people can never be considered truly stable or “recovering.” People cannot recover from age, and therefore, their condition is one of gradual and continuous deterioration. This means that a patient who is not at risk for developing pressure ulcers one day may become at risk the next day due to the natural course of deterioration in the patient’s tactile functions and mobility. Thus, nurses working with the elderly population must be ever vigilant for the signs of pressure ulcers (Pham et al., 2011).


According to Sullivan and Schoelles (2013), pressure ulcers occur in four stages. Similar to measurements of burn severity, each stage of pressure ulcer severity indicates a different depth and a new layer of tissue affected.

Stage One

At the first stage, which is the least severe, the ulcer has only affected the outer layer of skin. This stage is the most common due to nursing staff catching many ulcers before they become to severe. A patient experiencing a stage one pressure ulcer can expect to make a full recovery with minimal lasting tissue damage but with some scarring (Centers for Disease Control and Prevention [CDC], 2015).

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Stage Two

Pressure ulcers at stage two have moved beyond the outer layers of the skin and have reached the dermis but that have not gone all the way through. Ulcers at this stage are similar to stage one ulcers but may have a worse appearance due to the depth of tissue affected. Recovery without damage to tissue function can be expected, but scarring will be evident. Some function of skin pores in the area may be lost (CDC, 2015). Stage one and two pressure ulcers are accepted to a certain degree in the medical community. The United States Department of Health and Human Services (UDHHS) (2016) does not list stage one and stage two pressure ulcers as never events, meaning that they can be reimbursed by Medicare and Medicaid.

Stage Three

Pressure ulcers reaching stage three are ones that have moved completely through the skin and have begun to penetrate the underlying tissue, but that have not made it entirely through the fascia. The risk for infection is very high with these since the skin is completely penetrated, as is the risk of introducing other pathogens into the body or to create infections other than at the sight of the wound. Any patient with a stage three pressure ulcer is at risk of developing sepsis as a secondary result of the condition (CDC, 2015).

Stage Four

A stage four pressure ulcer is the most severe form and indicates that the lesion has passed completely through the fascia and into the underlying muscle and / or bone tissues. These type of ulcers are extremely dangerous and will most likely result in permanent tissue loss and impairment of function when they heal. Due to the muscles and bones affected, the loss of function will not be restricted to the tissue itself but to the patient’s ability to move that part of the body. Nerve damage is also possible which can affect any distal parts of the body from the wound site (CDC, 2015). Stage three and stage four pressure ulcers denote a degree of neglect on the part of nursing staff and are not an acceptable condition to occur in a clinical setting. According to the UDHHS (2016), pressure ulcers occurring while in medical or nursing care that are of stage three or stage four severity are considered never events, and the hospital will not receive reimbursement from Medicare or Medicaid for their treatment.


Bradford, N. K. (2016). Repositioning for pressure ulcer prevention in adults-A Cochrane review. International Journal of Nursing Practice, 22(1), 108-109. doi:10.1111/ijn.12426

Centers for Disease Control and Prevention (2015). Pressure ulcers among nursing home residents: United States. Retrieved November 13, 2016 from

Chou, R., Dana, T., Bougatsos, C., Blazina, I., Starmer, A. J., Reitel, K., & Buckley, D. I. (2013). Pressure ulcer risk assessment and prevention. Annals of Internal Medicine, 159(1), 28. doi:10.7326/0003-4819-159-1-201307020-00006

Coleman, S., Gorecki, C., Nelson, E. A., Closs, S. J., Defloor, T., Halfens, R., . . . Nixon, J. (2013). Patient risk factors for pressure ulcer development: Systematic review. International Journal of Nursing Studies, 50(7), 974-1003. doi:10.1016/j.ijnurstu.2012.11.019

Cullum, N. A., Mcinnes, E., Bell-Syer, S. E., & Legood, R. (2015). Support surfaces for pressure ulcer prevention. Cochrane Database of Systematic Reviews. doi:10.1002/14651858.cd001735.pub2

Fossum, M., Alexander, G. L., Ehnfors, M., & Ehrenberg, A. (2011). Effects of a computerized decision support system on pressure ulcers and malnutrition in nursing homes for the elderly. International Journal of Medical Informatics, 80(9), 607-617. doi:10.1016/j.ijmedinf.2011.06.009

Llano, J. X., Bueno, O., Rodriguez, F. J., Bagües, M. I., & Hidalgo, M. (2013). Prevention & treatment of pressure ulcers and nutritional status in elderly population. International Journal of Integrated Care, 13(7). doi:10.5334/ijic.1406

Pham, B., Teague, L., Mahoney, J., Goodman, L., Paulden, M., Poss, J., . . . Krahn, M. (2011). Early prevention of pressure ulcers among elderly patients admitted through emergency departments: A cost-effectiveness analysis. Annals of Emergency Medicine, 58(5). doi:10.1016/j.annemergmed.2011.04.033

Sullivan, N., & Schoelles, K. M. (2013). Preventing in-facility pressure ulcers as a patient safety strategy: a systematic review. Annals of Internal Medicine, 158(5), 410-416.

United States Department of Health and Human Services (2016). Never Events. Retrieved October 21, 2016 from

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