Surgery L2 - Wound Healing and Wound Closure

what are the 4 phases of wound healing? (VIPR)

- vascular

- inflammatory

- proliferative

- remodeling

what are the stages of wound healing? (5)

- injury

- hemostasis

- inflammation

- proliferation

- remodeling

what occurs in the inflammatory phase?

generalized inflammation around the wound edges

leukocytes mobilize to the injured area to remove debris and bacteria (lasts about 3 days if no contamination present)

what occurs in the proliferative phase?

production of fibroblasts and collagen

what is the role of fibroblasts?

what is the role of collagen?

synthesize collagen

helps to increase tensile strength of tissue around the wound

what occurs in the maturation?

remodeling of collagen by formation of intermolecular cross links, resulting in paler, flatter scars

what is primary intention closure?

recent, clean wounds that are closed by sutures

what are the characteristics of primary intention closure?

- typically irrigated and debrided to remove foreign material

- tissues brought together and accurate approximation to provide optimal healing

- wound becomes red, raised, and pruritic

- scar will flatten and become paler over 9-12 months

what is secondary intention closure?

wounds are left open to heal without surgical intervention

what are the characteristics of secondary intention closure?

- prolonged inflammatory phase

- wounds heal from the edges to the center and bottom up, about 1 mm per day

for which wounds are secondary intention closure indicated?

why?

severe infections and contaminated wounds

lowers the risk of abscess formation

what is tertiary intention closure?

when does tertiary intention closure occur?

closure of a wound that was initially left open or unrepaired

usually 3-5 days after initial injury

for which wounds are tertiary intention closure indicated?

- dog bites

- human bites

- severe crush injuries

what do good results of tertiary intention closure depend on?

- decreasing bacterial load

- good preparation of wound edges

- debridement of foreign material

what is the antibiotic of choice for human and dog bites?

Augmentin

what are the local and systemic factors that affect healing? (4)

- inhibition of the inflammatory response

- inhibition of wound healing

- lack of granulation tissue formation

- increased inflammatory response

what are the factors that inhibit the inflammatory response? (3)

- steroid use

- immunosuppressants

- chemotherapy

what are the factors that inhibit wound healing? (4)

- vitamin A deficiency

- zinc deficiency

- malnutrition (acute > chronic)

- steroid use

what are the factors that lead to the lack of granulation tissue formation?

- toxins

- septic shock

- gram negative infections

what factor increases the inflammatory response?

why might massive trauma increase the inflammatory response?

massive trauma

massive trauma > cytokine release > increased lactate production

what are post-operative factors for decreased wound healing?

- cardiac failure

- hypoxia

- poor tissue perfusion

- vasoconstriction

what are the suture types? (7)

- chromic gut

- vicryl

- PDS

- silk

- monocryl

- prolene

- nylon

what are the characteristics of chromic gut?

- absorbable

- made from collagen from bovine intestines

- used in OB/GYN, plastics, oral surgery

- loses tensile strength in 14-21 days

- risk of inflammatory reaction due to foreign protein nature

what are the characteristics of vicryl?

- absorbable and braided

- made from polyglycolic acid

- used in subcuticular approximation

- loses tensile strength in 14-21 strength

- risk of potentiating infections if wound is contaminated

what are the characteristics of PDS?

- absorbable and synthetic

- used in "tissue under tension" and contaminated wounds

- increased tensile strength

- poor knot security

what are the characteristics of silk?

- braided or entwined thread from silkworm lava

- non-absorbable

- treated with silicone to increase strength

- used in ocular, neural, closure of oral mucosa, and cardiovascular surgery

- cannot be used for grafts or prosthetic cardiac valves

what are the characteristics of monocryl?

- synthetic monofilament

- absorbable within 12 days

- loses tensile strength within 1-2 weeks

- used for wounds of the face, eyes, ears, neck, and abdomen and subcuticular closures

what are the characteristics of prolene?

- non-absorbable monofilament

- brittle and difficult to tie good knots

- easy removal due to lack of tissue adherence

- used in cardiovascular surgery, ophthalmic surgery, and neurosurgical procedures and high-tension wounds

what are the characteristics of nylon?

- non-absorbable monofilament

- has good tensile strength

- low skin reactivity

- used in laceration repairs and surgical incision closures

what are the 6 suture techniques?

- simple interrupted

- horizontal mattress

- vertical mattress

- deep dermal

- subcuticular

- running

what are the characteristics of simple interrupted sutures?

- most common suture technique

- mostly used in lacerations and incision closures

- potentially safer than running due to multiple separate sutures and knots

what are the potential complications of simple interrupted sutures?

- infection

- scarring

- ischemia and/or necrosis from excessively tight sutures

what are the characteristics of vertical mattress sutures?

- used in incisions or wounds that are under tension due to greater distribution of tension

- good to use in areas with convex surfaces

- allow the skin edges to evert

- remove in 4-6 days

what is a potential complication of vertical mattress sutures?

scarring (railroad tracks)

what are the characteristics of horizontal mattress sutures?

- used in incisions or wounds that under tension

- promote skin eversion to help limit scarring

- remove early to prevent scarring

what are the characteristics of deep dermal sutures?

- used when closing large or gaping wounds

- good for deep wounds/incisions

- help to reduce tension over the course of the wound

- require another layer of closure at the skin

- use a monofilament for lacerations and vicryl in a surgical setting

what are the characteristics of subcuticular sutures?

- most commonly use a running stitch

- placed into the epidural layer

- can use either nylon or monocryl

what are the characteristics of running sutures?

- used in longer incisions/wounds with minimal tension

- can be used to hold skin grafts in place

- faster closure

- most commonly use nylon

- only requires one knot to fail to allow for dehiscence

what are the characteristics of staples?

- quick wound closure

- secure with a low risk of failure

- quick removal but could be painful

- there is a concern for skin overgrowth if not removed in a timely fashion

- potential for an allergic reaction

what should you avoid when using staples for wound closure?

why?

inversion

to avoid wound breakdown and slower healing

what are the 4 types of knots?

- basic surgical knot

- surgeon's knot

- hand tying: 1 hand vs 2 hand

- instrument tying

what are the characteristics of a basic surgical knot?

- most common is a square knot

- typically 4-8 "throws" for a complete tie

- can result in "airballs" if the knot is not tight enough

what are the characteristics of a surgeon's knot?

- good for incisions/wounds under tension

- helps prevent loosening by locking the stitch in for the second "throw"

- helps prevent making the initial knot too tight and strangulation of the tissue

what are the characteristics of a 1 hand knot?

- faster

- better for tight spaces

- the tension is difficult to control

- potentially less secure

what are the characteristics of a 2 hand knot?

- better control of the knot

- more consistent tension

- slower

size, material, and removal time for sutures of the face/lip?

size, material, and removal time for sutures of the scalp?

size, material, and removal time for sutures of the chest/abdomen/back?

6-0, non-absorbable monofilament, 3-5 days

3-0 or 4-0, non-absorbable monofilament, 7-10 days

3-0 or 4-0, absorbable or non-absorbable monofilament, 10-14 days

size, material, and removal time for sutures of the limbs?

size, material, and removal time for sutures of the hands?

size, material, and removal time for sutures of the nailbed?

3-0 - 5-0, absorbable or non-absorbable monofilament, 10 - 14 days

4-0 or 5-0, non-absorbable monofilament, 10-14 days

6-0, rapidly absorbable braid, absorbed (no removal)