The following information was furnished by Gaymar
Industries, Inc. For more information on this topic, you may contact them
Pressure ulcers may be a
complication of immobility. The major cause of pressure ulcers is generally
accepted to be an external pressure that occludes blood vessels.
Two mechanical forces that contribute to pressure ulcers are a
combination of direct downward pressure and shear pressure.
Direct downward pressure, or tissue interface pressure (TIP), can
occlude blood capillaries and cause ischemia to the area supplied by the
affected vessels (figure 1).
Prolonged ischemia leads to cell
and tissue death. Shear pressure
is a horizontal force that occurs when the skin and underlying subcutaneous
tissues are pulled taunt and over-stretched, causing tissue deformity,
obstructing blood flow, and tissue necrosis (figure 2).
Many investigators have measured
the relative contribution of shear and pressure in causing the occlusion of
blood flow. It has been suggested
that in the presence of shear, the amount of direct pressure required to
occlude blood flow is reduced by a factor of 4.
and shear will be higher in areas where soft tissue
lies over bony prominences (figure 3). Since
pressure and shear are major causes of pressure ulcers, it is paramount that
these forces over bony prominences be reduced. *
is subject to the mechanical forces of pressure and shear.
In healthy individuals, the effects of pressure and shear are balanced
by protective mechanisms that impact the body response to those forces.
The ability to move and be active may be impaired in certain
populations, due to underlying medical conditions.
With any degree of immobility, the protective mechanisms are less
effective in balancing out the detrimental effects of pressure and shear.
strategies exist to manage the effects of pressure and shear in individuals
who have impaired mobility. A plan of care is developed to compensate for the inherent
disability. Initially, patient
education includes the importance of frequent turning and repositioning.
If a person is not able to move him or herself, the caregiver is
charged with the task of moving the patient/resident.
Turning and repositioning is the single most effective way to
compensate for impaired mobility. Unfortunately,
turning and repositioning a patient every two hours may not be enough to
prevent the development of a pressure ulcer.
It may not be in the best interests of the patient to be moved on a
recommended schedule. Another
strategy is to use a special support surface to assist in the management of
pressure and shear force.
search for the perfect support surface will prove fruitless because support
surfaces are but one facet of a total approach to pressure ulcer prevention.
To be complete, the plan of care will integrate support surfaces as an
integral part of the approach to total care management of pressure ulcers. *
of support surfaces for clinical use has been a source of frustration in the
recent past. The healthcare community is challenged to establish standards;
criteria for evaluation that are evidence based.
Randomized, prospective, controlled clinical trials have been the gold
standard, but they are an unrealistic approach due to cost.
Tissue interface pressure measurement is another approach to
evaluation. Incorporating shear
force into the equation is yet another approach.
Today, support surfaces may be evaluated in terms of their performance.
The features and benefits that support surfaces provide effect the way
they can meet patient needs. Clinical
application of support surfaces begins with a methodological approach to
selection of the appropriate support surface. *
important part of the prevention and treatment of pressure ulcers is placing
people on an appropriate support surface.
Choosing the appropriate support surface is not an easy task as there
is no standard criteria to evaluate support surfaces. Therefore, it is
important to assess the performance of each type of support surface
accurately, identify individual patient needs and then select the most
appropriate option based on a well-informed, educated approach.
the past three decades hundreds of support surfaces have been developed.
Support surfaces used for the prevention and treatment of pressure
ulcers may be classified according to their physical form and function. *
The three physical forms are:
form may take on special functions and offer features and benefits for the
prevention and treatment of pressure ulcers in targeted groups of individuals.
These functions may include:
(air fluidized, water, gel)
Mattress overlay is a general term to describe a support surface that is
placed on top of a mattress. Overlays
may be constructed of foam, air, or gel. Depending
upon the primary component, the overlay may then function as static,
alternating, low air loss or immersion. Assessment
of patient needs is matched to the performance of the support surface.
Patient assessment indicates the function and features that a support
surface must perform to meet the identified needs of the patient.
Mattress replacement for pressure ulcer management is a general term to
describe a support surface that totally replaces the standard mattress.
Mattress replacements may be constructed of foam, air, gel, or water.
The mattress replacement may be designed to provide a function such as
static air, alternating air, low air loss or immersion.
Once again, patient assessment is matched to the performance of the
support surface. Another way to categorize a mattress replacement is:
Full-framed specialty bed is a general term to describe a pressure
management support surface that is a totally integrated bed system, consisting
of mattress and bed frame. The
full-framed specialty bed replaces the entire conventional bed.
The pressure management support surface is usually constructed of air,
gel or water, or a combination of ingredients.
Depending upon the composition, the function may be alternating, low air
loss, high air loss, lateral rotation or immersion.
APPLICATION OF SUPPORT SURFACES
application of support surfaces begins with a methodological approach to the
selection of the appropriate surface. Many
types of support surfaces have been devised to prevent and treat pressure
ulcers. These surfaces have evolved
to take on various forms and functions, with different features and benefits.
Rather than a case by case choice, the process is simplified by
determining a standardized method for decision making.
concerning support surfaces are made within the framework of the patient care
This process takes into consideration two factors;
for patient assessment may include determining the risk for development of
pressure ulcers. Several tools are
available which have been validated through clinical research.
method of assessment involves consideration of available patient turning/sleep
the patient assessment is based upon, the goal is to match the patient need with
the features provided by the support surface.
The next question is what form and function does the surface provide and
can it meet the needs of the patient.
example of a methodology is Select The Optimal
Patient Support Surface
this picture to see a much larger image.
today’s healthcare arena, other criteria may also influence the decision
making process. These criteria may
include cost, ease of use, and support and service provided by the manufacturer.
within certain clinical areas may present with specialized needs related to
clinical area that presents with specialized needs is the peri-operative
arena. Due to constraints imposed by
patient positioning on surfaces that may not address pressure and shear
there is the potential for tissue damage.
Surgical procedures of greater than 2 hours and procedures that
involve the cardiovascular systems may cause an otherwise low risk patient
to be at high risk. Any
patients undergoing procedures of longer than 2 hours may be considered to
be at risk for pressure ulcers.
department procedures and protocol may cause individuals to spend long
periods of time reclining on surfaces that do not reduce or relieve pressure
in intensive care units often have critical or life threatening conditions
and co-morbidities that increase their risk for pressure ulcer development.
Many of these patients are either immobilized to some degree or are
not able to be moved due to instability of vital signs.
in transitional care units and skilled nursing units may have special needs
due to immobility or existing chronic wounds.
patients may also have special needs for support surfaces.
Maintaining the highest level of comfort may be the primary objective
with the terminally ill. The
performance of a support surface related to pain management becomes the
of the care setting, each clinical area and each individual within those
clinical areas must be assessed and their needs must be matched to the
appropriate support surface. The
methodology is a universal one and can be applied in any care setting.
Pressure ulcer prevention and treatment must include support surfaces and
any plan of care that omits support surfaces is incomplete.
Call Gaymar Industries, Inc. for references
Other companies with support surface products include:
Mason Medical Products