WOUND HEALING Flashcards
Class I - Clean
Infection Rate - 2-5 %
atraumatic, uninfected
no entry of GU, GI or respi tract
primarily CLOSED
if necessary, drained w/ closed drainage
breast surgery (MRM)
thyroid surgery
inguinal hernia
operative incisional wounds that follow non-penetrating (blunt) traums
Clean II - Clean Contaminated
Infection Rate - 8-11%
wound involving normal but. colonized tissue
MINOR breaks in sterile tissue
entry of GU, GI or respi tract w/o significant spillage
operations involving biliary tract, appendix, vagina and oropharynx
III - Contaminated
Infection Rate - 15%
wound w/ foreign or infected material traumatic wounds open, fresh, accidental wounds GROSS spillage from GIT ENTRY into INFECTED tissue, bone, urine or bile
operations w/ major break in sterile technique - OPEN CARDIAC MASSAGE
gross spillage from GIT
IV - Dirty
Infection Rate - 28-40%
old traumatic wounds w/ retained devitalize tissue and involve existing clinical infection or perforated viscera
organisms causing preoperative infection were present in the operative field before operation
Drainage of abscess
Debridement of soft tissue infection
Resection of infarcted bowel
Phases of Wound Healing
Hemostasis and Inflammation - PMN, macrophages, lymphocytes
vasoconstriction followed by vasodilation
time of injury - 7 days
Phases of Wound Healing
Proliferation - fibroblasts, endothelium
angiogenesis
collagen deposition
5 days - 3 weeks
Phases of Wound Healing
Maturation and Remodeling - fibroblasts
collagen cross linking and increasing tensile strength
3 weeks to 1 year
Steps of Wound Healing
Coagulation Inflammation Collagen Synthesis Angiogenesis Epithelialization Contraction and Remodeling
Primary Closure - healing by primary intention
requires clean tissue to be approximated w/o tension
surgical incisions closed by sutures, staples or adhesives, small cutaneous wounds, paper cuts
Secondary Healing - healing by secondary intention
wound left open to heal spontaneously after wound toilet and surgical debridement (maintained in PROLIFERATIVE phase until the wound closes)
depends on CONTRACTION and EPITHELIALIZATION
heavily contaminated wounds - abscess after incision or drainage, perineal wounds, perineum
wet to dry dressing
Tertiary healing or Delayed Primary Closure - healing by tertiary intention
wound initially managed as secondary intention (left open w/ dressing changes) then wound is closed after a few days when wound is clean and granulation tissue is abundant
traumatic injuries, dog bites or lacerations from foreign bodires
Factors Impairing Wound Healing
LOCAL infection foreign bodies ischemia or hypoxia venous insufficiency toxins previous trauma radiation cigarette smoking
SYSTEMIC malnutrition, cancer DM uremia jaundice old age systemic corticosteroids chemotherapeutic agents alcoholism
Superficial Incisional SSI
occurs w/n 30 days
skin and subcutaneous tissue of incision
purulent drainage from the deep incision
organisms isolated from an aseptically obtained culture of fluid or tissue from superficial incision
at least 1 of the ff: PAIN, TENDERNESS, LOCALIZED SWELLING, REDNESS or HEAT
Deep Incisional SSI
occurs w/n 30 days after operation if NO implant is left in place or 1 year if implant is in place
involves deep soft tissue of the incision (fascial and muscle layer)
at least 1 of the ff:
purulent drainage from the deep incision
deep incision that spontaneously dehisces or deliberately opened by a surgeon and i culture positive; fever, pain or tenderness
abscess or other evidence of infection involving the deep incision
Organ or Space SSI
w/n 30 days after the operation if no implant is left in place or w/n 1 year of implant is in place
infection involves any part of the anatomy (organs or spaces) other than the incision
purulent drainage from a drain that is placed into the organ or space
organisms isolated from an aseptically obtained culture of fluid or tissue in the organ or space
