NPWT in Pressure Ulcers
                     PRESSURE ULCER MANAGEMENT
Pressure ulcer is the most prevalent health issue all around the world. For every 1,000,000  
patients who developed Pressure ulcer 65,000 die from complications which presents a major  
challenge worldwide. Medical research is constantly striving to identify efficient ways for  
managing this long prevailing issue and reduce the fatality caused due to mismanagement of the  
pressure ulcers.
Lets understand a little about what exactly are these pressure ulcers, how are they formed and  
what are the current methods in practice for management of pressure ulcers.
What are Pressure Ulcers?
Pressure Ulcer commonly known as bed sore is an area on the body where there is damage to the  
skin & underlying tissue due to prolonged pressure, sheer, friction or a combination of all these.
Fig1. Causes of Pressure Ulcer Development
Pressure ulcers are commonly observed in the patients with decreased mobility like patients  
suffering with paralysis or the elderly. The ulcers can occur whenever the body has been in the
same position for long duration causing loss of blood flow and skin thinning to the bony  
prominence area. Hence to maintain the blood flow pressure off loading is highly essential for  
immobile patients. Image below depicts the pressure points where the ulcers can surface if the  
body remains in that position for higher durations.
Fig2. Common Points subjected to pressure ulcer
Along with the immobility of the patient there are certain other factors that cause the tissue  
more likely to become ischemic even under the same pressure these factors include presence of  
comorbities such as diabetes, multiple sclerosis, infection. Presence of any of these comorbities
can minimize tissue strength with the ability of nervous system respond & to initiate the healing  
process of the wound.
Intrinsic contributing factors include:
 Malnutrition
 Dehydration
 Impaired mobility
 Chronic conditions
 Impaired sensation
 Decreased LOC
 Infection
 Advance age
 Steroid use
 Pressure ulcer present
External contributing factors include:
 Pressure
 Friction
 Moisture
 Incontinence
 Shear
Stages of Pressure Ulcer
A pressure ulcer can range from a little discoloration of the skin to deep cavity wounds.  
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.
Fig3. Stages of Pressure Ulcer as per Sullivan and Schoelles
However National Pressure Injury advisory panel provides a slightly advanced classification for  
the pressure ulcers. These six stages are as follows.
Stage1: Non blanch-able erythma  Stage2: Partial thickness skin 
loss  Stage 3: Full thickness skin loss  Stage 4: Full thickness 
tissue loss
Stage 5: Unstageable – Depth unknown  Stage 6: Deep tissue injury 
Depth unknown
Fig4. Stages of Pressure Ulcer as per NPUAP
Fig5. Brief description for different stages of Pressure Ulcers
Pressure Ulcer Prevention
Pressure injuries can be prevented if acted upon timely; few general methods to be used are as  
below:
1. Pressure Distribution- This can be done using pressure re-distribution surface, positioning 
 devices, prophylactic dressings etc.
2. Positioning devices- Pillows can be used for offloading the pressure points
3. Avoid Sheer or friction – While repositioning the patient avoid causing friction or sheer  
to the skin
4. Micro shifting – Perform Small repositioning of the patient, especially in case of non  
rotating beds
5. Prophylactic dressings – Use of silicon based foam dressings can be very effective in  
preventing the wound from further injury
Wound Assessment
PUSH tool is widely used tool for assessing the pressure ulcers.
Nutritional Evaluation
Despite the consensus that adequate nutrition is important in wound healing, documentation of  
its effect on ulcer healing is limited; recommendations are based on observational evidence and  
expert opinion. Nutritional screening is part of the general evaluation of patients with pressure  
ulcers. In patients who are malnourished, dietary consultation is recommended and a swallowing  
evaluation should be considered. Intervention should include encouraging adequate dietary  
intake using the patient's favorite foods, mealtime assistance, and snacks throughout the day.  
High-calorie foods and supplements should be used to prevent malnutrition. If oral dietary intake  
is inadequate or impractical, enteral or parenteral feeding should be considered, if compatible  
with the patient's wishes, to achieve positive nitrogen balance (approximately 30 to 35 calories
per kg per day and 1.25 to 1.5 g of protein per kg per day). Protein, vitamin C, and zinc  
supplements should be considered if intake is insufficient and deficiency is present,
Method for Pressure ulcer wound management
There are various options available for the management of the pressure ulcers. Depending on the  
wound stage the most suitable option can be selected for administration.
Fig6. Pressure ulcer management algorithm


Significance of Negative Pressure Wound Therapy in management of pressure ulcers
NPWT should be considered first line of defense in case of stage IV pressure ulcers and highly  
exudating stage III pressure ulcers. Using NPWT on deep pressure ulcers that are not responding  
to any other treatment can significantly promote wound healing.
Using NPWT has multiple benefits such as
 Stimulates growth of new granulation tissue
 Angiogenesis
 Reduction of edema
 Sterile wound healing environment
 Enhanced wound perfusion
 Decreased bacterial contamination
 Decreased anaerobic activity
 Reduces frequent dressing
 Faster wound healing
 Reduced healing time
 Easy & early patient mobilization
 Clean & exudates free wound management
 Enhances patient’s quality of life
 Reduced infection risk from patient to attendee & from hospital to patient
Treatment Goals with NPWT
 Provide a temporary wound cover
 Manage wound fluid and edema
 Accelerate patient mobility
 Improve pain management
 Prevent wound progression
 Increase dermal and wound perfusion
 Stimulate formation of granulation tissue
 Enhance wound bed epithelialization
 Improve matrix material availability
 Reduce bacterial load
 Provide moist wound environment
 Influence expression of genes involved in wound healing
However while choosing NPWT as method of treatment always consider the contraindication of  
NPWT is the presence of necrotic or fibrotic tissue, untreated osteomylytis, absence of  
appropriate blood supply etc.
NPWT is based on assumption that a uniform negative pressure event three-dimensionally  
creates tissue deformation and cell stretching, leading to metabolic activity and cell proliferation.  
The most common dressing material is the polyurethane foam sponge with a wide variation in  
the coarseness of the mesh. The PU foam sponge maintains suitable moisture, it is generally  
accepted that moisture balance is essential to all phase of wound healing exposed cells of the  
wound surface require surface moisture for viability while too little can cause cell death, exercise  
can cause maceration and damage to would edges and peri-wound skin.
Conclusion
Wound care clinicians have a wide array of treatment options available with which to manage and help  
heal pressure ulcers. Few of the methods have been discussed above however, the challenge is to
determine the most appropriate treatment strategy while considering many factors regarding the wound,  
the patient, and the cost of care to ensure that assessments, treatment pathways, and product selections 
are  both clinically and economically sound.