Wound management TIME principle
The preparation and optimization of the wound bed for functional healing may not always result in complete healing, despite clinicians’comprehensive team efforts.It is important to treat the whole patient and not just the“hole” in the patient. It is also important to recognize that some wounds may remain in the static or “stalled” phase of the wound-healing trajectory.
Chronic wounds are often recalcitrant to healing and they often do not follow the expected trajectory (30% smaller in 12 weeks). They are disabling and constitute a signifcant burden on patients’ activities of daily living and the healthcare system. Of persons with diabetes, 2–3% develop a foot ulcer annually, while the lifetime risk of a person with diabetes developing a foot ulcer is as high as 25 percent. It is estimated that venous leg ulcers affect 1% of the adult population and 3.6% of people over 65 years old. As our society continues to age, the problem of pressure ulcers is growing.
Guide: Preparing the Wound Bed
|SI No.||Recommendation||Level of evidence|
|Identify and Treat the Cause|
|1||a. Determine if there is adequate blood supply to heal
b. Identify the cause(s) as specifically as possible or make appropriate referrals
c. Review cofactors/comorbidities (systemic disease, nutrition, medications) that may delay or inhibit healing
d. Evaluate the person’s ability to heal: healable, maintenance, non-healable
|2||a. Develop an individualized plan of care IV
b. Treat the cause(s) related to specific wound etiology/diagnosis
|Address Patient-centred Concerns|
|3||Assess and support individualized concerns
b. Activities of daily living
c. Psychological well-being
e. Access to care, financial limitations
|4||Provide patient education and support to increase adherence to treatment plan.||IV|
|Provide Local Wound Care|
|5||Assess and monitor the wound history and physical characteristics (location + MEASURE*). Measure, Exudate, Appearance, Suffering, Undermining, Re-evaluate and Edge||IV|
|6||Debride healable wounds by removing non-viable, contaminated or infected tissue
(through surgical, autolytic, enzymatic, mechanical or larval [biologic] methods). Non-healable wounds should have only non-viable tissue removed; active debridement to bleeding tissue is contraindicated.
|7||a.Gently cleanse wounds with low-toxicity solutions: saline, water and acetic acid (0.5–1.0%)
Topical antiseptic solutions should be reserved for wounds that are non-healable or those in which the local bacterial burden is of greater concern than the stimulation of healing. Do not irrigate wounds where you cannot see where the solution is going or cannot retrieve (or aspirate) the irrigating solution
|8||Assess and treat the wound for superficial critical colonization/deep infection/abnormal persistent inflammation (mnemonic IIa
NERDS), deep infection (mnemonic STONEES) or persistent inflammation: any 3 NERDS – treat topically: non-healing,
Exudate, Red-friable tissue, Debris, Smell; any 3 STONEES – treat systemically: ↑ Size, ↑ Temperature, Os, New breakdown,
↑ Exudate, ↑ Erythema/edema (cellulitis), Smell; persistent inflammation (non-infectious): topical and/or systemic anti-inflammatories
|9||Select a dressing to match the appropriate wound and individual person characteristics
Healable wounds: autolytic debridement: alginates, hydrogels, hydrocolloids, acrylics
Critical colonization: silver, iodides, PHMB, honey
Persistent inflammation: anti-inflammatory dressings
Moisture balance: foams, Hydrofibers, alginates, hydrocolloids, films, acrylics
Nonhealable, maintenance wounds: chlorhexidine, povidone-iodine
|10||Evaluate expected rate of wound healing: healable wounds should be 30% smaller by week 4 to heal by week 12
Wounds not healing at the expected rate should be reclassified or reassessed, and the plan of care revised
|11||Use active wound therapies (biological agents, skin grafts, adjunctive therapies) when other factors have been corrected and healing still does not progress.||Ia–IV
|Provide Organizational Support|
|12||For improved outcomes, education and evidence base must be tied to interprofessional teams with IV
the co-operation of health-care systems
The holistic approach to healable wound management stresses an accurate diagnosis and successful treatment with a team approach. For wounds that do not have the ability to heal, the approach is different . In these individuals, the inability to heal (nonhealable wound) may be due to an inadequate blood supply and/or the inability to treat the cause or wound-exacerbating factors. The second category, a maintenance wound, occurs when the patient refuses the treatment of the cause (e.g. will not adhere to compression therapy) or there is a health system error or barrier (e.g. no plantar pressure redistribution is provided in the form of footwear or the patient cannot afford the device). These may change, and periodic re-evaluation may be indicated.
Identify and treat the causes of the wound
Determine if there is adequate blood supply to heal
This is often important, especially for ulcers on the leg or foot. It is important to inspect the foot and lower leg for signs of arterial compromise (dependent rubor, pallor on elevation and loss of hair on the foot or toes), as well as palpating for a plantar pulse (dorsalis pedis or posterior tibial). Practitioners need to remember that a small percentage of patients may have an anomalous or anatomical variance resulting in absence of the dorsalis pedis artery. A palpable pulse indicates a foot arterial pressure of 80 mmHg or higher. . However, a palpable pulse may not always exclude an arterial etiology. Ankle brachial pressure index (ABPI) is indicated if the pulse is not palpable or to assess the appropriateness of high or modified compression bandaging for venous ulcers .The audible Doppler signals may also be useful diagnostically: a triphasic normal sound, a biphasic sound indicative of arterial compromise and the monophasic or absent signal with advanced ischemia. Complete segmental lower-leg arterial Doppler examinations. are needed if there is a possibility of a proximal lesion or arterial restriction or blockage that is amenable to surgical bypass or endovascular dilatation. If the blood supply is inadequate or cannot be immediately determined, dressing selection should be based on a maintenance wound program with moisture reduction and bacterial reduction until further assessments are performed. Toe pressures are useful because about 80% of people with diabetes and 20% of the nondiabetic population have calcified large leg arterial vessels that are nonpliable and stiff, leading to falsely high ABPI levels, often greater than 1.3.
Arterial status is related to vascular results
|>0.5||>50||>0.4||Biphasic/monophasic||30–39||Some arterial disease:
|<0.4||<30||<0.2||Monophasic||<20||High risk for
Review cofactors/comorbidities (systemic disease, nutrition, medications) that may delay or inhibit healing
Wound healing can be delayed or interrupted in persons with a coexisting systemic disease and the multiple comorbidities associated with chronic wounds. In the case of diabetes, excess glycosylation of hemoglobin due to poor diabetic glucose control can result in a prolonged inflammatory phase in addition to decreased neutrophil and macrophage phagocytosis of bacteria. Furthermore, diabetes affects the ability of erythrocytes to deliver oxygen to the wound, a fundamental step in collagen synthesis and tissue proliferation along with numerous other important factors in wound healing. A low protein intake or relative deficiency can prevent the production of granulation tissue and will contribute to a stalled healing environment for the wound. A given albumin measurement in a patient implies the nutritional status over a few months, and these levels are a gross indicator of long-term nutritional deficit. Albumin levels measure the large reservoir of amino acids that serve as the fundamental building blocks for wound healing.
Evaluate the person’s ability to heal: Healable,maintenance, nonhealable
Categorizing a wound according to its ability to heal (healability) assists the clinician in determining an accurate diagnosis along with a realistic individualized treatment approach. Adequate tissue perfusion is necessary for a healable wound. In order to be classified as a healable wound, the wound should have several attributes including an adequate blood supply; the cause of the wound must be corrected; and existing cofactors, conditions or medications that could potentially delay healing must be optimized or ideally corrected. A maintenance wound is a wound that may be healable but that either healthcare system factors or patient-related issues are preventing from healing. A nonhealable wound is a wound that does not have an adequate blood supply to support healing or the cause cannot be corrected. In nonhealable wounds, moist interactive healing is contraindicated and debridement should be a conservative basis only. Its been estimated that 70% of wounds are healable 25% in maintenance and 55% non healable. In general, advanced active therapies are not indicated for maintenance or nonhealable wounds.
When a healable wound does not progress at the expected rate, a chronic and stalled wound results. These wounds are more prevalent in older adults and are attributed to the aged skin and comorbidities such as neuropathy, coexisting arterial compromise, edema, unrelieved pressure, inadequate protein intake, coexisting malignancy and some medications. Persistent inflammation may be the cause of a stalled wound and in some cases may not be correctable. For nonhealable or maintenance wounds, pain and quality of life may be indicated as the primary goals of care. Palliative wound care often includes nonhealable wounds, but patients undergoing palliative care may have maintenance or even healable wounds.
Causes and Management of Pain
|Causes of Pain
|Pain at rest (related to wound Treat the underlying etiology of the wound and associated
etiology, infection, ischemia) pathologies.
|Provide analgesic and non analgesic options
per WHO Pain Ladder.
|Pain during day-to-day activities
(coughing, friction, dressing slippage)
|Pain from routine procedures Preparation and planning of the procedure are key to
(dressing removal, application) preventing pain.
|Analgesics per WHO Pain Ladder
should be administered before a procedure and may Dressing selection is key to
that would require an anaesthetic pain management with dressing removal and application.
|Pain associated with an intervention be required post procedure. (cutting of tissue or prolonged manipulation)|
Preparing the Wound Bed: Clinical and Physiological Mechanisms of Action
|Clinical Actions||Effect of Clinical Actions||Clinical Outcome|
|Tissue management/Debridement||Denatured matrix and
cell debris impair healing
or continuous) autolytic,
sharp surgical, enzymatic,
mechanical or biological
in wound base
|Viable wound base|
|Infection, inflammation||High bacteria, cause
↑ inflammatory cytokines
↓ growth factor activity
↓ healing environment
|Low bacteria, cause
↑ growth factor activity
↑ healing environment
|Bacterial balance and reduced inflammation|
|Moisture imbalance||Desiccation slows
epithelial cell migration
Excessive fluid causes
maceration of wound
Excessive fluid controlled
|Edge of wound –
cells, abnormalities in
extracellular matrix or
|Re-assess cause, refer
or consider corrective
• bioengineered skin
• skin grafts
• vascular surgery
|Responsive fibroblasts and keratinocytes
present in wound
All chronic wounds contain bacteria and the presence of bacteria obtained from a surface swab does not defne infection. In fact, the mean number of bacterial species per chronic ulcer has been found to range from 1.6 to 4.4. Critical to wound healing is whether bacterial balance is achieved (contamination or colonisation) or bacterial damage (critical colonisation or infection). The risk of infection is determined by the number and nature of invading bacteria as well as host resistance.
Host resistance is the most important factor and it refers to the host immune response to resist bacterial invasion and prevent bacterial damage.
Systemically, we need an adequate blood supply to heal and a decreased or inadequate blood supply favours bacterial proliferation and damage that may prevent or delay healing.
Uncontrolled oedema, smoking, poor nutrition, alcohol abuse, drugs that interfere with the immune system or immunodefciency diseases may all delay or prevent wound healing. Local factors inhibiting healing may include a large wound size, the presence of foreign bodies (prosthetic joints, a thread of gauze or a retained suture) and an untreated deeper infection such as osteomyelitis. External contamination of the wound bed by micro-organisms can occur from the environment, dressings, the patient’s secretions and hands along with the hands of healthcare provider.
Bacteria and chronic wounds.
alcohol rinse and hand washing
By using this superfcial and deep separation, the clinician can identify wounds with increased bacterial burden that may respond to topical antimicrobials and deep infection that usually requires the use of systemic antimicrobial agents.
The bacterial damage or infection mnemonic NERDS
|Letter||Description||Key information to know||Comments|
|The wound is non-healing despite appropriate interventions (healable
wound with the cause treated and patient centered concerns addressed)
Bacterial damage has caused an increased metabolic load in the
chronic wound creating a pro-infammatory wound environment that
|Wound size should decrease 30% after 4 weeks of appropriate
treatment to heal by week 12.
If the wound does not respond to topical antimicrobial therapy consider a biopsy after 4 to 12 weeks to rule out an unsuspected diagnosis such as vasculitis, pyoderma gangrenosum or malignancy
| An increase in wound exudate can be indicative of bacterial imbalance
and leads to periwound maceration
Exudate is often clear before it becomes purulent or sanguineous
|Increased exudate needs to trigger the clinician to assess for subtle
signs of infections
|When the wound bed tissue is bright red with exuberant granulation
tissues and bleeds easily bacterial imbalance can be suspected.
|Granulation tissue should be pink and firm. The exuberant granulation
tissue that is loose and bleeds easily refects bacterial damage to the
forming collagen matrix and an increased vasculature of the tissue
|D||Debris in the
|Necrotic tissue and debris in the wound is a food source for bacteria and
can encourage a bacterial imbalance
|Necrotic tissue in the wound bed will require debridement
Debridement choice needs to be determined based on wound type,
clinician skill and resources
|Smell from bacterial byproducts caused by tissue necrosis associated
with the infammatory response is indicative of bacterial damage.
Pseudomonas has a sweet characteristic smell /green color and
anaerobes have a putrid odor due to the breakdown of tissue.
|Clinicians need to differentiate the smell of bacterial damage from
the odour associated with the interaction of exudate with different
dressing materials particularly some hydrocolloids
The deeper infection mnemonic STONEES
|Letter||Description||Key information to know||Comments|
|S||Size is bigger||An increased size from bacterial damage is due to the bacteria spreading
from the surface to the surrounding skin and the deeper compartment.
This indicates that a combination of bacterial number and virulence has
overwhelmed the host resistance
|Size as measured by the longest length and the widest width at right
angles to the longest length. Only very deep wounds need to have
depth measured with a probe
|With surrounding tissue infection there is an increased temperature. This
may be performed crudely by touch with a gloved hand or by using an
infrared thermometer or scanning device, there is >3 degrees F difference
in temperature between two mirror image sites.
|Temperature differences can also be attributed to:
A difference in vascular supply (decreased circulation is colder) Extensive deep tissue destruction (acute Charcot joint)
|O||Os (probes to
|There is a high incidence of osteomyelitis if there is exposed bone or you
can probe to the bone in a person with a neurotrophic foot ulcer
|X-rays, bone scans and MRIs of underlying bone to confirm
|New satellite areas of skin breakdown that are separated from the main
ulcer can be indicative of deep infection.
It is important to remember this may also be due to the inability to correct
the cause of the wound or local factor leading to persistent damage
|Search for the cause of the satellite areas of breakdown and the
need to correct the cause
Check for local damage and consider infection, increased exudate or
other sources of trauma
|Increased exudate, erythema and oedema are due to the infammatory
response. With increased bacterial burden, exudate often increases in
quantity and transforms from a clear or serous texture to frank purulence
and may have a haemorrhagic component. The infammation leads to
vasodilatation (erythema) and the leakage of fuid into the tissue will
result in oedema.
|Match the absorbency of the dressing (none, low, moderate, heavy) to amount of exudate from the wound.|
|S||Smell||Bacteria that invade tissue have a “foul” odour. There is an unpleasant
sweet odour from pseudomonas /gm. Negative organisms and anaerobe
organisms can cause an putrid smell from the associated tissue damage.
|Systemic antimicrobial agents are indicated that will treat the causative
organisms and devitalised tissue should be aggressively debrided in
wounds with the ability to heal.
Do not use topical or systemic antibacterial agents long-term without weighing the benefts and the risk. Discontinue antibacterial agents after the wound is in bacterial balance unless the patient is prone to re-infection due to local or systemic factors such as immunecompromise.
Deep tissue infection may penetrate to bone and produce osteomyelitis. Ulcers probing to bone or exposed bone in persons with diabetic foot ulcers is a reliable and valid sign of osteomyelitis in the majority of patients. Surrounding tissue infection is referred to as cellulitis and classically pain is associated with increased temperature, edema and erythema. Cellulitis greater than 2 cm, on the leg or foot in a person with diabetes can be associated with limb threatening infection. Systemic antimicrobial therapy depends on local practice. In general chronic wounds are first affected by gram positive bacteria in the first month and after that time gram negatives and anaerobes invade the tissue as well. The diagnosis of infection is made clinically and swab results are used to identify organisms and their antimicrobial sensitivity.
Appropriate moisture is required to facilitate the action of growth factors, cytokines, and migration of cells including fibroblasts and keratinocytes. Moisture balance is delicate act. Excessive moisture can potentially cause damage to the surrounding skin of a wound leading to maceration and skin breakdown. Conversely, inadequate moisture in the wound environment can impede cellular activities and promote eschar formation resulting in poor wound healing. A moisture-balanced wound environment is maintained primarily by ‘modern dressings’ with occlusive, semi-occlusive, absorptive, hydrating and haemostatic characteristics, depending on the drainage of the wound bed.
It is noted that a 20 to 40% reduction in two and four weeks is likely to be a reliable predictor of healing.A 50% reduction at week four was a good predictor for persons with diabetic foot ulcers. One measure of healing is the clinical observation of the edge of the wound. A non healing wound may have a cliff like edge between the upper epithelium and the lower granulation in comparison to a healing wound with tapered edges like the shore of a sandy beach. If the wound edge is not migrating after appropriate wound bed preparation (debridement, bacterial balance, moisture balance) and healing is stalled, then advanced therapies should be considered. The first step prior to initiating the edge effect therapies is a reassessment of the patient to rule out other causes and co-factors. Clinicians need to remember that wound healing is not always the primary outcome. Consider other wound related outcomes such as: reduced pain reduced bacterial load, reduced dressing changes or an improved quality of life. Several edge effect therapies support the addition of missing components: growth factors, fbroblasts or epithelial cells or matrix components.
In summary, the concept of wound bed preparation includes the treatment of the whole patient before the hole in the patient (treat the cause and patient-centered concerns).The steps of wound bed preparation Tissue management, Infection control, Moisture balance and Epithelization( TIME) are key to wound healing. Support in the way of “other products,” services and nutrition is also needed. Finally, always remember that education is the scaffold for practice. Without it, clinicians cannot advance practice and improve patient wound healing outcomes