Voices From The Community | Spinal Cord Injury & Paralysis

​Thinking Differently About the Causes of Pressure Injury Part 1

Written by Nurse Linda | Jun 8, 2022 4:00:00 AM

A pressure injury is an issue for individuals with paralysis from any disease or trauma. Individuals with less sensation are at the highest risk; however, individuals with sensation also have the risk of developing a pressure injury as well. Suppose you have sensation issues on just one side of your body. In that case, you can develop pressure injury in areas where sensation is challenged and body areas where sensation is present if moving is difficult. Individuals with diabetes or poor circulation can develop pressure injury as sensations and responses may not be messaged well to the brain.

Pressure injury can even affect individuals who have complete sensation. It is often seen under casts, prosthesis, and equipment that have rubbed. Some people get a pressure injury from shoes that rub their feet. Changes in body metabolism can increase the risk of pressure injuries such as dehydration, malnutrition, and skin texture and integrity changes. Wet skin from incontinence, sweat, or poorly drying after bathing can lead to pressure injury.

Other words for pressure injury include pressure sore, bedsore, decubitus ulcer or decub, skin breakdown or ‘a spot’. Pressure injury (P.I.) is the current choice of name in healthcare today. This occurs when pressure from inside the body pushes on blood vessels disrupting circulation or blood flow to the inner tissue. You may not know when a pressure injury begins because you cannot see it forming. Individuals will first notice a pressure injury starting with the outer skin changing color from lack of circulation inside the body. But the injury has already been created inside the body. Many compare a pressure injury to an iceberg, you see a bit of it on top of the skin, but there is much, much more going on underneath the surface of the skin.

A pressure injury is often caused by a hard pointy bone being pressed on internal blood vessels, blocking blood flow. These include arteries, veins, and capillaries. Arteries carry oxygen and nutrients from the blood to the cells of the body. These are the largest and have the thickest blood vessels' walls. The heart’s greatest pumping pressure of blood is directly through the arteries. Pressure in the arteries depends on how your heart beats and the resistance of the artery wall. Arteries can become thicker and less elastic with cardiac issues such as atherosclerosis (hardening of the arteries), so failure or rupture can occur with artery changes which increase pressure injury risk.

Veins have less pressure as they carry blood away from the cells of the body, returning the blood to pick up oxygen from the heart. The arteries and veins connect to each other by capillaries. This is where the switch from carrying blood to the cells to carrying blood away from the cells occurs. Capillaries are the smallest and most delicate blood vessels. It takes very little pressure for a short amount of time to compress the capillaries, which can quickly collapse, interrupting blood flow. Lack of blood flow to the cells of the body leads to little or no oxygenation or nutrients delivered to the cells causing them to die. When the capillaries fail, veins and arteries quickly follow, leading to pressure injury.

Pressure injuries are the results of this interruption in body circulation. The signs of a pressure injury on the outside of the body are changes in skin tone, swelling, pain or referred pain, tenderness, changes in skin temperature including feeling cooler or warmer to touch than the surrounding area, skin loss, pus, odor, and drainage.

By the time you see changes in your skin, a pressure injury already has a good grip inside your body. Pressure injuries are classified in stages. Stage one is a change in pigmentation on the outside of your body. The change in pigmentation may be darker or white (ashy) in individuals with more melanin in their skin. Individuals with less melanin may have a pink, red, or purple area. Noticing this change, especially over a pointy bone or boney prominence, is critical as more damage is below the surface of the skin in your tissues, so stage one should be taken very seriously.

Stage two is the change in pigmentation, but also the skin surface may be blistered or even open if the top layer of skin is removed. If the skin is intact, keep it as it is. Opening the skin can lead to infection. If the skin is open on its own, keep the area covered to prevent infection with a nonstick bandage. You do not want the skin to be removed by changing a bandage that has stuck to this delicate top layer. The top layer of skin is very resilient and can heal quickly if pressure is no longer applied to the area. However, healing the pressure injury inside the body will take more time.

Stage three is a deep wound, including an opening where you can see the fat that is under your skin. The wound may be infected, contain pus, have drainage, and may have a foul odor. This wound needs to be covered to prevent infection or further infection and to contain drainage until you can see a health professional for further instruction.

Stage four is a very deep wound, down to the bone. You may see the bone when you look inside the opening. It is very prone to infection. Infection in the bone is life-threatening.

Unstageable wounds are open, but you see a white, black, or yellow covering when you look inside the wound. This is the body’s way of temporarily closing the wound, but it can be the source of infection, or infection can be under the covering. Since you cannot see inside the wound, the stage cannot be estimated. Do not disturb this injury. Instead, get instructions on how to care for this wound.

Removing pressure in the area of injury is the way to allow the body to heal. This means not sitting, laying or otherwise allowing any pressure. Do not rub this area or press it, as this adds more pressure from the outside of the body and the pressure already present inside the body.