1. Principles of Wound Closure
Bucky Boaz, ARNP-C

2. History of Wounds Herbal balms and ointments
Initially, wounds were left open
Oldest suture 1100BC
Primary and secondary closure 2000 yrs ago
Middle ages: pus thought necessary
Recent wound closure less that 200 yrs old
Initial treatments for wounds consisted of herbal balms with application of leaves or grass as bandages. Ointments were made from a wide variety of animal, vegetable, and mineral substances
Wounds were mostly left open
The world’s oldest suture was placed by an embalmer on the abdomen of a mummy in approximately 1100 BC
During early civilization, the care of wounds was dominated by magic and rituals
Celsus first described primary and secondary wound closure more than 2000 years ago
During the middle ages, pus was believed to be necessary for healing.
Advances in the field of anesthesiology and surgery during the past 2 centuries have led to the development of many of the practices today

3. Physiology of Wound Healing
Epithelial
cells
Wound occurs
Blood leaks
STOP
A brief review of the physiology of wound healing provides a basis for understanding the process of healing and repair.
When a wound occurs, blood leaks from the surrounding vessels into the wound space produced. Immediately after the bleeding has stopped and a clot has formed, enzymes are released that stimulate the epithelial cells to migrate towards each other at high rates of speed.
However, the scab that is forming is in the way, causing an obstruction in which the epithelial cells are impeded in their migration across the space of the wound. The cells eventually bridge this gap and link into a continuous layer.
This layer thickens and the subcutaneous layers begin to return to their normal structure, pushing off the scab and leaving a scar in its wake.
Scab causes obstruction
Thickening and return
to normal state

4. Specific Points Affecting Wound Healing
Keep wound clean and scab free
Keep wound moist
Avoid steroid creams
Suturing wound splints skin
Wounds actually shrinks
The scab is a significant object in a sutures wound, so keeping the wound clean and scab free allows for quicker and smoother epithelization. This can accomplished by postoperative care, including daily cleaning with hydrogen peroxide or soap and water.
The epithelial cells survive and move much better in a moist environment, so keeping the wound moist (without maceration) enhances this process.
The wound’s natural inflammatory process is important because new collagen formation, which occurs under the epithelial cells, is catalyzed by normal inflammation.
Epithelialization occurs only on the surface of the wound. The strength of a wound is in the collagen fibers and connective tissue supporting the surface. The rebuilding of these fibers takes some time, and suturing a wound splints the skin together until new connective tissue is built.
Wounds actually shrink. This is a factor that must be considered in the placement of sutures and in the shape of wounds

5. Evaluation of the Patient
Risk of infection or poor wound healing
Detailed history of medicinal or latex allergies
Immunization status
It is important to identify conditions that place the patients at risk for infection or delayed healing after wound closure
Cruise and Ford (1973) studied 23,000 surgical incisions: identified diabetes mellitus, obesity, malnutrition, chronic renal failure, advanced age, and use of steroids as increased wound infection rates.
Because anesthetic agents and antibiotics may be required for many patients, a detailed history of any allergies to these agents is essential. With the increased incidence of severe reactions to latex products, it is vital to review any previous allergies to latex.
Tetanus immunization status should be verified
Clean minor wounds = less than 10 yrs NO
All other wounds = less than 5 yrs No

6. Evaluation of the Laceration
History of mechanism
Potential for significant injury
Potential foreign body
Possible rabies exposure
Type of force applied to injury
Adequate lighting
Neurovascular assessment
A history of the mechanism of injury is essential to help identify the presence of any potential wound contaminants and foreign bodies that can result in chronic infection and delayed healing. Failure to diagnose foreign bodies is the fifth leading cause of litigation against emergency physicians. Other common wound-related causes of litigation include the development of wound infections and missed injuries of tendons and nerves.
Crush injuries, which tend to cause greater devitalization of tissue, are more susceptible to infection than are wounds resulting from the more common shearing forces.
Adequate wound examination should always be conducted under optimal lighting conditions with minimal bleeding. Cursory examination under poor lighting conditions or when the depths of the wound are obscured by blood ultimately result in underdetection of embedded foreign bodies and damage to important structures such as tendons, nerves, and arteries.
One way to minimize the possibility of missing an injury to a vital structure is to start the wound examination with a neurovascular assessment of pulses, motor function, and sensation distal to the laceration.

8. Classification of Wounds
Abrasions
Lacerations
Crush wounds
Puncture wounds
Avulsions
Combination wounds

12. Anesthesia of the Laceration
Lidocaine with/out epi, marcaine
TAC
Local vs regional
Mechanisms to reduce pain
Methods to reduce pain of local infiltration for lidocaine
Small-bore needle (27G)
Buffered solution
Warmed solution
Slow rates of injection
Injection through wound edges
Subcutaneous rather than intradermal injection
Pretreatment with topical anesthetics

13. Wound Preparation Removal of hair Scrubbing the wound
Not eyebrow
Scrubbing the wound
Irrigation with saline
Avoid peroxide, betadine, tissue toxic detergents
Removal of the hair surrounding a laceration helps facilitate meticulous wound closure. Because many bacteria normally reside in hair follicles, shaving of the hair before repair may increased wound infection rates. Reduced damage to hair follicles may be achieved with the use of hair clippers instead of a razor. Most practitioners avoid removal of the eyebrow hair, because its removal may result in abnormal regrowth.
Direct scrubbing of the wound with a sterile surgical brush helps remove both bacteria and particulate matter that potentiate the risk of wound infection. However, scrubbing also contributes to tissue damage and reduces the ability of the wound to resist infection.
High pressure irrigation (5-8 psi) is recommended for best outcome of reducing bacterial count and reducing infection rates.

14. Wound Closure Timeframe
Morgan et al
Arm and hand: 4 hours = difference
Baker and Lanuti
Arm and hand: 6 hours = no difference
Jamaica
Face: no time limit
Trunk and extremity: 19 hours = difference
Morgan et al 1980
Baker and Lanuti 1990
Jamaica 1988

15. Ideal Wound Closure Allow for meticulous wound closure
Easily and readily applied
Painless
low risk to provider
Inexpensive
Minimal scarring
Low infection rate

16. Options for Wound Closure

17. Sutures Non-absorbable sutures Tinsel strength 60 days Non-reactive
Outermost closure
Non-absorbable sutures, such as nylon and polypropylene, retain most of their tensile strength for longer than 60 days, are relatively nonreactive, and are appropriate for the outermost layer of the laceration
Removal is required

18. Sutures Absorbable sutures Synthetic > natural
Synthetic increases wound tinsel strength
Deeper layers
Avoid in highly contaminated wounds
Avoid in adipose tissue
Synthetic & monofilament > natural & braided
Absorbable sutures are usually used for closure of deeper structures deeper than the epidermis
In general, synthetic sutures are less reactive and have greater tensile strength than sutures from natural sources, such as catgut. They increase the time during which the healing wound retains 50% of its tensile strength from less than 1 week to as long as two years.
Chromic gut lasts for up to 2 weeks and is associated with tissue reactivity
Deep sutures help relieve skin tension, decrease dead space and hematoma formation, and probably improve cosmetic outcome.
Deep sutures should be avoided in highly contaminated wounds, where they increase the risk of infection.
Sutures through adipose tissue do not hold tension, increase infection rates, and should be avoided

19. Sutures Advantages Disadvantages Time honored Meticulous closure
Greatest tensile strength
Lowest dehiscence rate
Disadvantages
Requires removal
Requires anesthesia
Greatest tissue reactivity
Highest cost
Slowest application

20. Staples More rapidly placed Less foreign body reaction
Scalp, trunk, extremities
Do not allow for meticulous closure
Staples can be applied more rapidly than sutures. They are associated with a lower rate of foreign body reaction and infections.
Able to use in scalp, on trunk and extremities. Not over joints.
Do not allow for meticulous closure

21. Staples Advantages Disadvantages Rapid application
Low tissue reactivity
Disadvantages
Less meticulous closure
May interfere with some older generation imaging techniques (CT, MRI)

22. Adhesive Tapes Less reactive than staples
Use of tissue adhesive adjunct (benzoin)
Poor outcome in areas of tension
Seldom used for primary closure
Use after suture removal
Surgical adhesive tapes are less reactive than staples, but they require the use of adhesive adjuncts that increase local induration and wound infection
Tape alone cannot maintain wound integrity in areas subject to tension.
They are seldom recommended for primary wound closure, but are often used after suture removal to decrease tension on the wound until they fall off.

23. Adhesive Tapes Advantages Disadvantages Least reactive
Lowest infection rate
Rapid application
Patient comfort
Low cost
No risk of needle stick
Disadvantages
Frequently falls off
Lower tensile strength than sutures
Highest rate of dehiscence
Requires use of toxic adjuncts
Cannot be used in areas of hair
Cannot get wet

24. Tissue Adhesives Dermabond, Ethicon Topical use only
Outcome equal to 5-0 and 6-0 facial repairs
Less pain and time
Slough off in 7-10 days
Act as own dressing
No antibiotic ointment
Tissue adhesives have been in use for several decades in Europe and Canada. Approved for use in the US in August 1998.

25. Tissue Adhesives Advantages Disadvantages Rapid application
Patient comfort
Resistant to bacterial growth
No need for removal
Low cost
No risk of needle stick
Disadvantages
Lower tensile strength than sutures
Dehiscence over high tension areas (joints)
Not useful on hands
Cannot bathe or swim

26. Post-procedural Care Dressing for 24-48 hours Topical antibiotics
Start cleansing in 24 hours
Suture/staple removal
Face 3-5 days
Non-tension areas 7-10 days
Tension areas days

27. Choosing Your Suture 6-0 5-0 4-0 3-0 Face Chin Low tension/detail
Large laceration
Moderate tension
3-0
Significant tension

28. The Interrupted Stitch

29. The Interrupted Stitch
Instrumentation
Hemostat
Scissors
Forceps with teeth
Plain forceps
Control syringe
Tub for saline
Gauze
Sterile towels
Syringe and splash shield

30. The Interrupted Stitch
Finger tip grip
Palm grip
Grip needle one-third of way from thread

31. The Interrupted Stitch
Curl needle into dermis of 1st side

32. The Interrupted Stitch
Curl needle into dermis of 1st side
Curl needle trough parallel opposite subcutaneous side

33. The Interrupted Stitch
Curl needle into dermis of 1st side
Curl needle trough parallel opposite subcutaneous side
Tie square knot with at least two braids

34. The Interrupted Stitch
Curl needle into dermis of 1st side
Curl needle trough parallel opposite subcutaneous side
Tie square knot with at least two braids
Repeat three to four throws

35. Procedure Note 6cm right upper arm laceration repair
1% lido c/ epi, irrigated c/ NS, betadine prep and sterile drape. Explored: no vascular involvement, barely into muscle body of triceps. Closed with 4.0 monosoft interrupted sutures. Good wound edge approximation. Topical antibiotics and dressing. Tolerated procedure well.

36. Points to Remember Specific points affecting wound healing
Evaluation of laceration and neurovascular assessment
Types of sutures
Staples
Adhesive tapes
Tissue adhesives

37. Points to Remember Advantages vs disadvantages Post procedure care
Choosing your suture
Instruments
Be able to perform interrupted suture for lab final

38. Questions?