BASIC PRINCIPLES OF
WOUND DRESSING
LEARNING OBJECTIVES
• At the end of the lesson : student will be able to ;
• define wound
• State the types of wound and how they are being
caused.
• State the importance of wound care.
• Enumerate the local and general signs and symptoms of
an infected wound.
• Describe the process of wound healing.
• Explain the phases of wound healing.
• State the classifications of wound.
• Discuss the factors that affects wound healing.
• List some of the factors that promote wound healing.
• Acquire knowledge on the types dressing to be applied
on different types of wounds
• State the properties of ideal dressing.
• Demonstrate activities nurse will consider or perform
prior to wound dressing .
• Demonstrate how to dress patient wound at the ward
aseptically.
• HOW DO YOU UNDERSTAND THE TERM WOUND.
WOUND is a break in the continuity of the skin. A wound
can also be explained as any injury to living tissues
(usually one in which the skin is broken) caused by a cut,
blow, or other impact.
It can also be described as break or disruption in the normal
integrity of the skin and tissues.
It may be superficial, affecting only the surface structures
or severe involving the blood vessels, muscles, nerves,
tendons and ligament.
Wounds may result from mechanical force (surgical incisions) or
physical injury (such as burn).
Types of wounds
Incised wound (Incision)
• It is an open wound which has its edges smooth and even. It is acquired as a
result of cutting from a sharp instrument. The wound edges are always in
close approximation and aligned. Example: an incision done on a patient
during operation or surgery which is called incisional wound. The wound
usually bleeds freely but heals quickly.
Contused wound (contusion)
• This is closed wound which occurs from a blow from a blunt instrument.
The skin appears bruised (ecchymosis) because of a release of blood into
tissues from a damaged blood vessel.
Abrasion wound
• It is considered as an open wound occurring as a result of friction such
as scrapped knee from a fall on a rough surface.
Punctured wound (stab wound)
• This is an open wound made by a sharp instrument that penetrates the
skin and underlying tissues e.g. nail prick or done intentionally by a
surgeon puncturing to insert drainage tube to tap fluid from a particular
cavity in the body. In this type of wound the depth is greater than the
length and there is danger of deep organs being damaged.
Lacerated wound (laceration)
• This occurs as result of tearing apart of a tissue, producing irregular
wound edges e.g. animal bite.
Why do we have to care for patient wound?
Importance of wound care
It prevents the entry of pathogenic organisms
It promotes healing
It protects the wound from further Injury
It reduces haemorrhage by applying pressure where there is
bleeding from the wound
It also prevents odour from the wound
It helps dressing materials to absorb exudates
Symptoms of wound infection
Foul smell
Discharge or filled with pus
Discolouration of the wound
Swelling after the inflammatory stages
Gaping of the wound
Local symptoms
Inflammation
Redness
Heat
Swelling
Pain
Loss of function
General symptoms
Elevation of body temperature
Increase in pulse rate and respiration
General malaise
Anorexia
Nausea
Chills
Wound healing process
• Healing is a process of cure; the restoration of
integrity to injured tissue.
• It is a process of rupturing to normal function of the
tissues after a period of injury.
• There are three types of wound healing process;
primary or first intention, secondary or second
intension and tertiary intention
• Primary intention: wounds healed by primary
intention are well approximated (skin edges are tightly
together).
• Intentional wounds with minimal tissue loss.
• Such as those made by surgical incision with sutured
approximated edges, usually healed by primary
intension.
• This is the union of the edges of a clean incised
wound leaving only a faint linear scar
CHARACTERISTICS OF WOUND THAT HEALS BY FIRST INTENTION
1.It only occur in healthy wounds, where there is no infections.
2. It is the quickest method for wound to heal.
3. It usually occurs within five to ten days.
4. The edges are brought together in two ways;
By stitching together, or clipping edges or adhesive dressing
The wound edges should be positioned so that it comes together
Secondary intention
• wounds healed by secondary intention have edges that are not well
approximated.
• Large open wounds. Such as from burns on major trauma, which require
more tissue replacement and are often contaminated usually heal by
secondary intention.
• If a wound that is healing by primary intention becomes infected, it will
heal by secondary intention.
• Wounds that heal by secondary intentions take longer to heal and form
more scar tissue.
• Healing by secondary intention is union by closure of a wound with
granulations.
• This is the slowest method of healing and occurs in lacerated and septic
wounds.
Tertiary intention
• wounds healed by tertiary intention or delayed
primary intention are those wounds
• left open for several days to allow oedema or
infection to resolve or exudate to drain, and then are
closed.
• It is the union of the skin several days after surgical
closure or injury.
• It exhibits signs of discharge. E.g. a gapped wound
after surgery.
Phases of wound healing
• It is referred to as regeneration (renewal) of tissues.
• It can be broken down into three phases
1.Inflammatory phase
2. Proliferative phase
3. Maturation phase
Inflammatory process
• The inflammation occurs immediately after injury
and last for 3 to 4 days.
• The immediate response of the body is to stop
bleeding and to prevent microorganisms from
entering the wound.
Two major processes occur during this phase:
• haemostasis and phagocytosis.
• Haemostasis (the cessation of blood), vasoconstriction occur
in the immediate areas around the wound to reduce the flow
of blood to the wound.
• This is triggered by the release of serotonin and other
chemical mediators from the platelets.
• Damage to blood vessels in the muscles and skins around the
wound causes the released platelets to become sticky and
clump together to form a platelet thrombosis or plug.
• This helps to reduce bleeding.
• Subsequently the inflammatory process is triggered.
• Chemical mediators including prostaglandins are
released to the wound.
• The chemical mediators cause capillary permeability
which further results in vasodilation.
• The permeability allows for migration of mediators
• such as neutrophils, monocytes, plasma proteins and antibodies
into the wound.
• These mediators, especially neutrophils and microphages
phagocytose dead tissues and microorganisms that may have
invaded the wound.
• This increase blood flow and inflammatory processes results in
redness, swelling, heat, pain and in some instance loss of function
of the part affected
Proliferative phase
• Second phase in healing,
• extends from day 4 to about day 28 post injury.
• Connective tissues known as fibroblasts migrate into the wound to synthesize
collagen.
• Collagen is a whitish protein substance that adds tensile strength to the wound.
• As the amount of collagen increases, so does the strength of the wound, thus the
chance that wound will open progressively decreases.
• During this time, a raise appears under the intact suture lines.
• In a wound that is not sutured, the new collagen is visible.
• Capillaries grows across the wound increasing the blood supply which brings
oxygen and nutrients needed for healing.
• As the capillaries network develops, the tissue becomes a translucent red colour
known as granulation
• granulation tissue. The granulation tissue is very fragile and bleeds
easily.
• When the skin edges of the wound is sutured, the area must be filled in
with granulation tissues.
• At maturation, the granulation tissue migrates to proliferate over the
connective tissue base to fill the wound.
• If the wound does not close and epithelial cells migrate to it (thus if the
wound is closed by epithelialization, the area becomes covered with
dried plasma protein and dead cells). This is called eschar.
• Initially the wound healing by secondary intention seep drainage later
if they are not covered by epithelial cells, they become covered with
thick grey, fibrinous tissue that is eventually converted into dense scar
tissue.
Maturation phase
• The maturation phase begins about 21 and can extend
to 2 years after the injury.
• Fibroblast continue to synthesize collagen.
• The collagen fiber themselves, which were initially
laid in a haphazard fashion, recognize into a more
orderly structure, the scar becomes a thin, less elastic
white line.
Enumerate some of the causes of wound infection?
Factors that delay wound healing
Infection delays wound healing
Resistant organisms – if the pathogens in the wound
are resistant to antibiotics, healing will delay
Discharging wounds do not heal in time
The presence of a sinus or fistula
If a wound is sutured under tension, healing is delayed
because the surrounding tissue are unduly stretched
Poor health e.g. anaemia
 Drugs – patients on certain drugs have delayed
wound healing (cortisone therapy)
Age – aging delays wound healing
Obesity – blood flow to the site becomes
inadequate
Mention some of the Factors that will promote
wound healing
Factors that promote wound healing
Good health
Balanced diet
Young age
Absence of any other disease and infections
Strict aseptic technique in wound dressing
 Proper use of drugs
Complications of wound
 Bleeding
 Shock
 Infection
 Scar formation
 Keloids
 Contractures
 Fistula
 Dehiscence (is partial or total rupturing of wound by skin repair)
• Evisceration (is a protrusion of internal visceral content of the abdomen)
Dressing of wound
• A dressing is a sterile pad or compress applied to a wound to promote
healing and protect the wound from further harm.
• A dressing is designed to be direct contact with the wound.
• Dressings are best used on wounds that are moderately inflamed with
obvious debris and pale, translucent – appearing necrotic tissue.
• Such wounds usually have watery exudates. Sterile gauze pads may be
used dry on wounds, or may be soaked with sterile saline.
• These applications are known as ‘dry-to-dry’ or ‘wet-to-dry’ and the
function is help debride the wound and remove necrotic tissues and loose
debris.
Types of wound dressing
• Dry-to-dry
• Used primarily for wounds closing by primary
intention. Layer of wide mesh gauze lies next to the
wound surface, second layer of dry absorbent cotton to
protect the wound.
Wet-to-dry
• Dressing may be applied to wounds when exudates are sticky.
• These are particularly useful for untidy or infected wounds that must be
debrided and closed by secondary intention.
• The objective of the wet-to-dry dressing technique is to clean a wound or
help to prevent build- up of exudates.
• Why is it wet-dry dressing
• because you place a moist dressing on the wound and allow it to dry.
• When the dressing is removed, it takes with it the exudate, debris and
nonviable tissue that have become stuck to the gauze.
• Wet-to-dry dressing are indicated for wounds that are dirty or infected.
Techniques for using the wet-dry dressing
• Moisten a gauze dressing with solution, and squeeze
out the excess fluid.
• The gauze should be damp, not soaking wet,
completely open the gauze (it usually comes folded)
and placed on the wound.
• You do not need many layers.
• Then cover with a thin layer of dry gauze.
Wet-to-wet
• Used in clean open wounds.
• A wet-to-wet dressing does not debride the wound, which
remains as it is.
• The dressing remains wet so that when the gauze is
removed, the top layer of the healing wound is not removed
with it.
• This dressing should be used on clean, granulating wounds
with no overlying exudates in need of removal.
Techniques for using the wet-wet dressing
• Moisten the gauze dressing with solution.
• It should not be soaking wet, but it should be a little wetter
than damp.
• Unfold the gauze, place it over the wound, then cover with
dry gauze.
• The dressing should still be wet or damp when it is changed.
• If the bottom layer of the gauze has dried out, saturate the
gauze with saline or water before removal.
What are some of the Properties of an ideal
dressing
Properties of an ideal dressing
Bacteria proof
Allows gaseous exchange
Manages exudate
Non-adherent
Fibre and toxin free
Hypoallergic
Maintain haemostasis and optimal temperature
Acceptability to patient
Cost effective
What are some of the points to Consider prior to
wound dressing
Considerations prior to wound dressing
1. The nurse must assess the wound and type of the dressing applied to the
wound.
This will helps to;
• determine whether the procedure will be aseptic or otherwise
• determine the mount of consumable such as cotton wool, gauze and
plaster required for the procedure.
2. The nurse must also determine whether the wound discharges.
• This can be observed from the state of the dressing applied previously.
• This is essential to determine whether wound swabbing will be required
for laboratory investigations.
3. Consider whether the wound has clips or sutures that require
removal.
This is essential to guide the nurse in setting a standard trolley
which will include instruments for the removal of the sutures/clips.
This can be determined from the patient’s folder and the changes
book.
4. The nurse must also determine whether the wound has drainage
tubes that require shortening or removal.
This information can be gathered from the patient’s folder and
changes book.
5. Aseptic technique should be employed in wound dressing to reduce the number of
microorganisms.
The following precautions should therefore be considered:
 Activities such as sweeping and bed making should be completed at least one hour
before dressing are started.
 Floors should be mopped to prevent dust from settling on the wound.
 The wards should be closed to all unnecessary human traffic while dressing is being
done.
 Windows and doors should be closed before and during dressing.
 To prevent contamination of wounds by infected droplets of moisture from the nose and
mouth, mask should be worn while dressing a wound.
 The hand should be washed and kept dry and not to be allowed to come into contact
with the wound.
THANK YOU FOR YOUR TIME