Skin wounds. Classification

1. Soft Tissue Injuries
o Trauma that happens to the skin is visually
exposed
o Categorized as a skin wound
o Defined as a break in the continuity of the
soft parts of body structures caused by a
trauma to these tissues
o Mechanical forces include:
o Friction, scraping, compression, tearing, cutting,
penetrating

2. Skin Wounds
Classification

3. Abrasion
o Skin scraped against
a rough surface
o Several layers of skin
are torn loose or
totally removed
o Usually more painful
than a deeper cut b/c
scraping of skin
exposes millions of
nerve endings

4. Classification of Wounds
• 1) Clean Wound:
●
Operative incisional wounds that follow nonpenetrating
(blunt) trauma.
• 2) Clean/Contaminated Wound:
●
uninfected wounds in which no inflammation is encountered
but the respiratory, gastrointestinal, genital, and/or urinary
tract have been entered.
• 3) Contaminated Wound:
●
open, traumatic wounds or surgical wounds involving a
major break in sterile technique that show evidence of
inflammation.
• 4) Infected Wound:
●
old, traumatic wounds containing dead tissue and wounds
with evidence of a clinical infection (e.g., purulent drainage).

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6. Classification of Wounds Closure
• Healing by Primary Intention:
●
All Layers are closed. The incision that heals by first
intention does so in a minimum amount of time, with no
separation of the wound edges, and with minimal scar
formation.
• Healing by Secondary Intention:
●
Deep layers are closed but superficial layers are left to heal
from the inside out. Healing by second is appropriate in
cases of infection, excessive trauma, tissue loss, or
imprecise approximation of tissue.
• Healing by Tertiary Intention:
●
Also referred to as delayed primary closure.

7. Abrasion

8. Abrasion—Treatment
o Wash wound to remove all dirt and debris
o Soap and water or hydrogen peroxide
o Scrub wound if particles of dirt, rocks, or tar
embedded
o Leave open to air, unless oozing of fluid or
blood
o Apply antibiotic ointment to inhibit infections
o Scrapes scab over quickly

9. Abrasion—Treatment
o Loose skin flaps my form natural dressing; if flap
dirty remove with clean nail clippers
o Check on date of last tetanus immunization
o Watch for signs of infection
o Seek medical attention if any of following:
o Pain increases after several days
o Redness/red streaks appear beyond edges of wound
o Swelling
o Purulent drainage

10. Laceration
• Flesh irregularly torn; cut or tear in the skin
• Minimal bleeding, minimal pain, & no
numbness or tingling
• Cuts ≤ 0.25” (6mm) deep and 0.5” (1.3cm) long
& have smooth, edges→ can be treated at home
• Deeper lacerations should be treated by physician
(stitches)

11. Laceration

12. Laceration

14. Laceration—Treatment
o Cleaned with soap and water
o Irrigate with clean water to remove debris
o Do NOT use alcohol, iodine, or peroxide
as it may cause further damage and slow
healing process
o Stop bleeding
o Cover wound with sterile gauze
o Apply direct & constant pressure (15min+)

15. Laceration—Treatment
o Once wound cleaned,
antibiotic ointment may
be applied to reduce
risk of infection & aid
healing
o Change sterile dressing
daily as needed
o Bruising and swelling
are normal
o Apply ice to site
o Elevate area above level
of heart
o Contact a physician if:
o Laceration more than
0.25” (6mm) deep and
0.5” (1.3cm) long
o The wound is in area
where wound by be
opened by simple
movement of body part
o Wound on face, eyelids,
or lips
o Deep cuts on palm,
finger, elbow or knee
o Loss of sensation or
ROM of body part as
result of cut

16. Stitches Steri-Strips®

20. Amputation

22. Avulsion
o Layers of skin torn off completely or only
flap of skin remains
o Same mechanism as laceration, but to
extent that tissue is completely ripped
from it’s source
o May be considerable bleeding

23. Avulsion—Treatment
o Clean wound with soap and water
o If flap of skin remains connected→ replace
skin in its original position
o If deep avulsion, seek medical attention for
stitches
o If large piece of skin torn off→ place in plastic
bag and put on ice
o Skin should not get frozen or soaked in water
o Take skin in plastic bag to doctor; may be able to
save and replace torn-off piece

24. Puncture Wound
o Penetration of skin by sharp object
o Nails, tacks, ice picks, knives, teeth, needles
o May be small in diameter and not seem
serious
o Do require treatment by physician
o Can become infected easily b/c dirt and
germs carried deep in the tissue

25. Puncture Wound—
Treatment
o Find out if part of object that caused wound
still in the wound
o i.e. lead from a pencil
o Determine if other tissues have been injured
by the object
o Blood vessels, nerves, tendons, ligaments,
bones, internal organs
o Prevent infections
o Bacterial skin infections, tetanus, infections in
deeper structures (bones and joints)

26. Puncture Wound—
Treatment
o Risk of infections increases if:
o wound was exposed to soil (may contain
tetanus or other bacteria)
o went through sole of shoe (↑ risk of
bacterial infection that is difficult to treat)
o injected into skin under high pressure
o i.e. nail from nail gun, paint from high-
pressure paint sprayer
o Physician should be consulted if object
penetrated deeply

27. Contusion
o A blow compresses or crushes
the skin surface and produces
bleeding under the skin
o Does not break skin
o Bruising due to injury to blood vessels
o Most mild and respond well to RICE

28. Contusion—Signs & Symptoms
o Swelling
o Pain to touch
o Redness
o Ecchymosis
o accumulation of blood in
skin & subcutaneous
tissue more than one cm in
diameter
o General term=bruising
o Result of bleeding; clotting
or bleeding disorders
o Bluish lesion at earliest
stages of onset

29. Contusion—Treatment
o Careful monitoring
o Anti-inflammatory oral medications
o Compressive dressing
o Ice
o Modalities to ↓ ecchymosis, ↓ swelling, ↑ ROM
o Myositis ossificans: calcification that forms
within muscle
o Requires surgical intervention

30. Blister
o Continuous rubbing over the
surface of the skin causes a
collection of fluid below or
within the epidermal layer

31. Blister—Treatment
o Wash area thoroughly
o Use sterile blade to
cut small hole in
blister
o Squeeze out clear
fluid
o Do not remove skin
o Prevention:
o Wear work gloves
o Break in new shoes
o Petroleum jelly/skin
lube
o Adhesive bandage

32. Incision
o Skin has been sharply cut
o Surgical cut made in skin or flesh

33. Incision—Treatment
o Remove bandage day after surgery;
replace daily or as needed
o Normal for edges of healing incision to be
slightly red
o Call physician if:
o redness increases/spreads more than half an inch
o pus in incision
o more than mildly tender or painful

34. Incision—
Treatment
o Keep incision clean & dry for several days
after surgery
o Non-absorbable sutures or staples must
be kept dry until doctor removes
o Steri-strips® should be kept dry 4-5 days
o On face, hands, arms: take showers or tub
baths along as affected area stays dry

35. Wound Healing
– Inflammation occurs when the damaged
endothelial cells release cytokines that
increase expression of integrands in
circulating lymphocytes.
– Histamine, serotonin, and kinins cause vessel
contraction (thromboxane), decrease in blood
loss, and act as chemotactic factors for
neutrophils, the most abundant cells in the
initial 24 hour period.

36. Wound Healing
– Proliferative phase occurs next, after the
neutrophils have removed cellular debris and
release further cytokines acting as attracting
agents for macrophages.
●
Fibroblasts now migrate into the wound, and secrete
collagen type III.
●
Angiogenesis occurs by 48 hours.
●
The secretion of collagen, macrophage remodeling
and secretion, and angiogenesis continues for up to
3 weeks.
●
The greatest increase in wound strength occurs
during this phase.

37. Wound Healing
– Maturation phase is the final phase and
starts from the 3rd week and continues for up
to 9-12 months.
– This is where collagen III is converted to
collagen I, and the tensile strength continues
to increase up to 80% of normal tissue.

41. Surgical Wound Infection (SWI)
– Incisional infections identified by purulent or
culture positive drainage is isolated from any
structure above the fascia in proximity to the initial
wound
– Deep infections are characterized by purulent
drainage from subfascial drains, wound
dehiscence, or abscess formation and involve
adjacent sites manipulated during surgery.
– Wound Dehiscence
– Breakdown of the surgical wound

42. Risk Factors for SWI
– Patient-related factors:
– Age > 60, sex (female), weight (obesity)
– Presence of remote infections
– Underlying disease states
– Diabetes, Congestive heart failure (CHF)
– Liver disease, renal failure
– > 72 hours, ICU stayDuration of preoperative stay
hospitalization
– Immuno-suppression
– ASA (American Society of Anesthesiologists)
– physical status (3,4, or 5)

43. Risk Factors for SWI
Surgery-related factors:
– Type of procedure, site of surgery, emergent
surgery
– Duration of surgery (>60- 120 min)
– Previous surgery
– Timing of antibiotic administration
– Placement of foreign body
– Hip/knee replacement, heart valve insertion, shunt
insertion
– Hypotension, hypoxia, dehydration, hypothermia

44. Risk Factors for SWI
Surgery related factors:
– Patient preparation
– Shaving the operating site
– Preparation of operating site
– Draping the patient
– Surgeon preparation
– Hand washing
– Skin antiseptics
– Gloving

45. Risk Factors for SWI
Wound-related factors:
– Magnitude of tissue trauma and devitalization
– Blood loss, hematoma
– Wound classification
– Potential bacterial contamination
– Presence of drains, packs, drapes
– Ischemia

46. Questions?