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

a. Pain

b. Activities of daily living

c. Psychological well-being

d. Smoking

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



Toe pressure


Toe brachial



Ankle Doppler






>0.8  >80 >0.6 Normal/triphasic >40 No relevant

arterial disease

>0.5  >50 >0.4 Biphasic/monophasic 30–39 Some arterial disease:

modify compression


>0.4  >30 >0.2 Biphasic/monophasic 20–29 Arterial disease



<0.4  <30 <0.2 Monophasic <20 High risk for

limb ischemia




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


Characteristics  Management Strategies


Background 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.


Incident pain


Pain during day-to-day activities

(coughing, friction, dressing slippage)


Procedural pain


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.



Operative pain


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 Observations


Molecular and 

Cellular Problem

Clinical Actions Effect of Clinical Actions Clinical Outcome
Tissue management/Debridement Denatured matrix and

cell debris impair healing

Debridement (episodic

or continuous) autolytic,

sharp surgical, enzymatic,

mechanical or biological

Intact, functional

extracellular matrix

proteins present

in wound base

Viable wound base
Infection, inflammation High bacteria, cause

↑ inflammatory cytokines

↑ proteases

↓ growth factor activity

↓ healing environment




protease inhibitors

growth factors

Low bacteria, cause

↓inflammatory cytokines

↓ proteases

↑ growth factor activity

↑ healing environment

Bacterial balance and  reduced inflammation
Moisture imbalance Desiccation slows

epithelial cell migration

Excessive fluid causes

maceration of wound


Apply moisture-balancing


Desiccation avoided

Excessive fluid controlled

Moisture balance
Edge of wound – 

non-advancing or





Non-responsive wound

cells, abnormalities in

extracellular matrix or

abnormal protease


Re-assess cause, refer

or consider corrective

advanced therapies

• bioengineered skin

• skin grafts

• vascular surgery

Responsive fibroblasts and keratinocytes

present in wound

Advancing edge

of wound


Wound bed preparation TIME

Wound bed preparation TIME


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.

Level Bacterial status Treatment




Infection control:

alcohol rinse and hand washing




Critical colonisation


Topical antimicrobial

and deep


Infection Systemic agents
Systemic Sepsis Parenteral therapy


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
N Non-healing


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

delays healing

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

E Exudative


   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

R Red &



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

S Smell from

the wound

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

T Temperature


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

or exposed


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


N New areas



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

EE Exudate


and oedema

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.


Moisture balance

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