Tag Archives: pressure injury

Pressure Injury Prevention: Managing Shear and Friction

Let us start off this post with a typical scenario. You walk into any facility or institution and you see a patient slouched in their wheelchair, with no wheelchair cushion. You notice part of their brief hanging out of the top of their pants, so you assume the patient may be incontinent. So let’s think about this for a minute. We most likely have friction, shear, and moisture going on with this patient.

This scenario is the perfect recipe for a pressure injury. So what can we do to help this patient and prevent a pressure injury from developing? We must first identify the cause, and then remove the cause. The cause in this example is shearing, friction, moisture, and pressure. We will remove the pressure injury causes with interventions such as using a 4 inch viscoelastic wheelchair cushion, Dycem® non-slip matting to keep the patient in place, and offloading the patient every hour while up in wheelchair.

The NPUAP pressure injury definition states that the ability of soft tissue to tolerate shear and pressure may also be affected by the factors of microclimate, nutrition, perfusion, comorbidities, and condition of the soft tissue. We still do not know whether shear damages muscle more than fat, the relationship between external and internal shear, or the affect of postural changes (frequency of speed or changes have on shear force).

Identifying signs of shearing and friction

Many times you may identify signs of shearing stresses within a wound that presents an irregular shape and undermining. There may even be evidence of excoriation and blistering on areas in contact with support surfaces. Friction usually, but not always, accompanies shear. Friction is the force of rubbing two surfaces against one another. Shear is a gravity force pushing down on the patient’s body with resistance between the patient and the chair or bed.

What can we do to reduce friction and shearing in managing our patients?

  1. Pad and protect vulnerable areas (transparent, hydrocolloid, composite, foam dressings) as per facility protocol.
  2. Use heel or elbow protectors for hospice/palliative patients.
  3. Educate caregivers and nursing staff about how to identify key factors for pressure injuries.
  4. Ensure that support surfaces provide for individual’s particular needs: pressure redistribution, shear reduction, and or microclimate control.
  5. Utilize positioning devices in wheelchairs or chairs to reduce shearing.
  6. Establish a risk assessment per facility protocol.
  7. Use draw sheets to pull up, transfer and position your patient. DO NOT DRAG.

via Wound Source

Frequently asked questions about support surfaces

The National Pressure Ulcer Advisory Panel (NPUAP) describes support surfaces as “specialized devices for pressure redistribution designed for management of tissue loads, microclimate, and/or other therapeutic functions.” These devices include specialized mattresses, mattress overlays, chair cushions, and pads used on transport stretchers, operating room (OR) tables, examination or procedure tables, and gurneys. Some support surfaces are part of an integrated bed system, which combines the bed frame and support surface into a single unit.

Support surfaces must be used in conjunction with other interventions, such as nutritional support, skin care, repositioning, pressure redistribution, risk identification, and patient and caregiver education. Although studies have shown that support surfaces can help decrease the incidence of pressure injuries (PIs), there is no evidence showing one brand or type of support surface is better than another.

What does it mean when a support surface is described as reactive or active?

Reactive surfaces, also called reactive/continuous low pressure, may be powered or not powered and can adjust pressure redistribution only when a load (such as the weight of a patient) is applied to it.

An active surface is always powered. Pressure distribution is adjusted mechanically, even when there is no patient on the surface.

What materials are used in support surfaces?

Materials include foam, gel, fluid, and silicone beads. Australian medical-grade sheepskin is also used, but has limited availability in the United States. Some support surfaces have covers made of Gore-Tex® or another material that helps reduce friction.

What do the terms immersion, envelopment, and bottoming out mean?

Pressure redistribution with support surfaces is achieved through immersion and envelopment.

Immersion refers to the fact that as the body sinks into the surface, pressure is redistributed over the entire area of contact and not just the bony prominences. Envelopment is the ability of the support surface to conform evenly to irregularities, such as body contours, linens, and the patient’s clothing, without causing excessive pressure on the body.

Bottoming out refers to the patient’s body sinking in so deeply on the support surface that it rests against the bed frame or another surface, such as a gurney, that lacks sufficient cushioning.

What is microclimate control?

Microclimate control (control of temperature and moisture) is achieved by:

controlling the airflow against the skin by pumping air through minute perforations in the surface cover

increasing the exchange of air between the skin and the surface through the use of porous covers that allow moisture evaporation and body heat dissipation.

This feature keeps the skin cool and dry.

Microclimate control is beneficial for patients who are constantly moist (for example, diaphoretic or incontinent). Excess moisture raises the risk of friction and shear, which can result in skin breakdown. The coolness feature helps avoid higher skin temperature, a risk factor for PIs.

What do the features lateral rotation, alternating pressure, low air loss, and air fluidized mean?

These features are the functional or therapeutic components of a support surface. They can be used singly or in combination.

With continuous lateral rotation, or simply lateral rotation, the surface provides rotation longitudinally (head-to-toe), turning the patient to a set degree, in a set duration, and at a set frequency. Rotation is limited to 40 degrees or less to each side. Lateral rotation does not replace repositioning the patient to address skin issues, nor does it provide pressure redistribution or offloading. Instead, surfaces with this feature help facilitate pulmonary hygiene among patients with acute respiratory conditions.

NPUAP defines alternating pressure as “a feature of a support surface that provides pressure redistribution via cyclic changes in loading and unloading as characterized by frequency, duration, amplitude, and rate of change parameters.” Surfaces with alternating pressure may be mattresses or overlays and are always powered. They can change distribution of load with or without applied load—even when no patient is in the bed. These surfaces have air cells that cyclically inflate and deflate, thus changing the areas of the body under pressure.

Low air loss means that the surface provides flow of air to help manage the microclimate of the patient’s skin.

Air-fluidized surfaces provide pressure redistribution by immersion and envelopment, using a fluid-like medium created by forcing air through silicone beads. Air-fluidized surfaces are expensive and difficult to maintain; beds with these surfaces are usually rented instead of purchased. They are heavier than a standard bed, so are not always suitable to place in older homes.

Air-fluidized beds are often used for patients with multiple full-thickness wounds or who have undergone myocutaneous procedures. They are not typically recommended for a patient with an unstable spine or pulmonary disease. The fluid-like surface doesn’t provide sufficient support for a patient with an unstable spine, and for patients with pulmonary disease, the lack of firm support makes it difficult for patients to cough effectively.

What are general considerations for matching patients to appropriate support surfaces?

It’s important to base the choice of support surface on individual patient needs. (See Determining type of support surface.) For example, consider the patient’s weight, height, and shape. (Bariatric patients must use bariatric surfaces; be aware of the weight limitation of the surfaces.)

Other considerations include:

risk for new PIs

number of current PIs, including severity and location

patient’s activity, mobility (for example, avoid surfaces that might make it difficult to get a patient out of bed), and moisture

risk for falls and entrapment in the bed

appropriateness for the setting (for example, powered surfaces can’t be used in a home without a reliable power source).

Consider contraindications when choosing a support surface. For example, reactive/constant low pressure, reactive/constant low pressure with low air loss, active surfaces with alternating pressure feature, and air-fluidized surfaces are contraindicated for patients with unstable cervical, thoracic, and lumbar spines, and patients with cervical or skeletal traction.

Assess the appropriateness of the choice on a regular basis. For example, a patient with multiple stage 3 PIs that have healed may no longer need the surface with low air loss but can now be placed on a reactive/ constant low pressure surface. If a patient experiences pain or discomfort with a particular surface, consider alternatives.

What are important points to remember when using support surfaces?

Education is key to promote optimal use of these surfaces. Staff such as nurses, certified nursing assistants, and other team members who handle the surfaces, including housekeeping and maintenance staff, all need information on how to use the support surface correctly. Education should extend to families, caregivers, and patients in the home setting.

Although the manufacturer may state an expected lifespan for a product, staff must be taught that the lifespan can be shorter, depending on use. Staff need to be aware of indicators of wear and tear; discoloration; any change in height or thickness of the surface; any break in the seams, cover, zippers, flaps; breakdown of internal components; or presence of foul odor. Deficient products must be repaired or replaced.

Other important points related to using support surfaces include the following:

Ensure the appropriate type and number of linens or liners are used with the surfaces. For example, a liner with a plastic bottom is not ideal with low air loss surfaces because the non-breathable feature of the plastic will not allow the air from the support surface to go through.

Clean surfaces as specified by the manufacturers. If the correct cleaning process is not used, the surface poses an infection risk. Incorrect use of agents, for example using products that destroy the integrity of the cover, also increases the risk of cross-infection.

Most importantly, remember that patients must still be repositioned even if they are in a support surface. An active support surface should be used when frequent manual repositioning is not possible. When possible, avoid positioning a patient with an existing PI on the affected area.

What should facilities use as support surfaces in the OR, ED, and procedure areas?

Support surface options for the OR include air, gel, and high-specification foam mattresses. Consider the patient position required for the procedure when making a selection. There are also pads with pressure redistribution properties that can be used for transport and on ED beds. More research is needed to determine the effectiveness and proper use of these support surfaces. When selecting products to use in these special situations, consider safety, care, and costs.

Understanding support surfaces

Support surfaces are an integral part of PI prevention and treatment. When selecting a surface, the patient’s individual needs, including past experiences with the surfaces, must be taken into consideration. It’s important for clinicians to continuously assess patients for the appropriateness and the functionality of the surface.

Armi S. Earlam is the lead certified wound, ostomy, and continence nurse at Lutheran Medical Center in Wheat Ridge, Colorado.

Selected references

Centers for Medicare and Medicaid Services. National Coverage Determination (NCD) for air-fluidized bed (280.8).

Mackey D, Watts C. Therapeutic surfaces for bed and chair. In Doughty D, McNichol L, eds. Core Curriculum: Wound Management. Philadelphia, PA: Wolster Klower; 2016:362-83.

McNichol L, Watts C, Mackey D, et al. Identifying the right surface for the right patient at the right time: generation and content validation of an algorithm for support surface selection. J Wound Ostomy Continence Nurs. 2015;42(1):19-37.

Moore Z, Stephen Haynes J, Callaghan R. Prevention and management of pressure ulcers: support surfaces. Br J Nurs. 2014;23(6):S36-S43.

National Pressure Advisory Panel. Terms and definitions related to support surfaces. 2007.

National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel, & Pan Pacific Pressure Injury Alliance. Prevention and treatment of pressure ulcers: clinical practice guidelines. Osborne Park, Australia: Cambridge Media; 2014.

A pressure ulcer by any other name

Just when we think we’ve figured out pressure ulcer staging, it changes again. In April 2016, the National Pressure Ulcer Advisory Panel (NPUAP) held a consensus conference on staging definitions and terminology. The purpose: to analyze and discuss the rationale for the panel’s changes. One of the key changes is replacing the term “pressure ulcer” with “pressure injury.” So instead of calling it a pressure ulcer staging system, NPUAP will refer to it as a pressure injury staging system. The panel explained that the new terminology “more accurately describes pressure injuries to both intact and ulcerated skin.” Other changes include:

use of Arabic rather than Roman numerals in the stage names

modified descriptions of each individual stage (although the underlying definition of each stage remains the same.)

The revised staging guidelines, along with new schematic artwork for each stage, are available for free download.

More than 400 people attended the conference. (I assume most were experienced in wound care.) I wasn’t able to attend, so I reached out to several clinicians who did and found that their reactions were mixed.

Here are some of their responses:”

“I was surprised the updated pressure injury guidelines were released so soon.”

“This was presented by industry experts. I preface what I am about to say with this comment because of the concern I had with the updated staging system by end of the meeting.”

“During a picture review of wounds, incorrect responses were greater than 40%. What became frightfully obvious to me was that if the experts were having trouble identifying the wounds correctly, [it would be even more difficult for nonexperts].”

“I thought the process would serve to simplify and clarify. I’m not so sure it accomplished either.”

“Was any thought given to how the changes will affect the conflicts between clinician documentation and the various mandatory reimbursement tools used in different healthcare settings?”

Obviously, comments were all over the board, but I did note a common theme: confusing. Based on attendees’ feedback, I urge wound care clinicians to read the new guidelines carefully and take care in implementing them. And keep in mind what Shakespeare said: “A rose by any other name would smell as sweet.” So pressure ulcers, now called pressure injuries, will still require the skilled care of expert clinicians.

Donna Sardina, RN, MHA, WCC, CWCMS, DWC, OMS

Editor-in-Chief, Wound Care Advisor

Cofounder, Wound Care Education Institute