Wound Healing Flashcards
First 3 step in the inflammatory phase ?
Hemostasis with a fibrin-platelet clot
Platelets release platelet-derived growth factor (PDGF)
Provisional matrix develops in first 24 hours
What are PMN role in the inflammatory phase in wound healing ?
They arrive through leaky capillaries, attracted by the PDGF growth factor releases by the platelets
Enhance cell migration
Phagocytose the clot
Kill bacteria
Inflammatory phase Last step: By __-__ hours, macrophages release growth factor
48-72
Proliferative Phase ?
72 hours after the wound started, fibroblasts provide structure to the wound in the form of collagen
Intramolecular cross-linking occurs, giving strength
What cell is mostly involved in the Proliferative Phase ?
fibroblasts
Remodeling / Maturation phase ?
By 2-3 weeks after the wound, the density of inflammatory cells and new capillaries start to resolve by apoptosis
Simultaneous collagen increase and breakdown
Remodeling phase can last months to ______ as collagen fibrils get more organized and cross-linked
2 years
Remodeling phase: Visible scars that remain are due to ?
residual disorganized collagen
If the inflammatory process lasts too long, persistent ___ and __________ activity cause increased collagen synthesis, leading to ?
PMN and macrophage
Hypertrophic scars
Keloids
Last 2 steps in the remodeling phase ?
Wound contraction occurs
Fibroblasts attach to the collagen matrix and contract the network
In surgical wounds, contraction can _____ or ___________ – undesirable look
shorten or depress scars
In circular incisions (anastomosis) contraction can cause ?
stenosis
Contraction occurs less over tighter skin (eg. shoulder) than over _______ (eg. groin)
loose skin
Epithelialization specific to ?
skin and gut tissue
Epithelialization occurs in what phase ?
Inflammatory
In a well-approximated wound, epithelialization is nearly complete at __-__ hours
24-48
In an open wound, this would take days to months
Epithelialization
Epithelialization benefits/facts ?
Provides a barrier on the skin to water, bacteria and other items in the environment
Multilayered by a few days
Sterile dressing in OR – do not remove for 3-4 days unless it gets wet
In a_____________ wound, minimal dermis is lost so wound heals by epithelialization
partial-thickness
Partial-thickness wound heals from ?
Wound heals from edges and from epidermal islands
1-2 mm/day
In open, ____________ wounds, epithelial cells can migrate only from the edges of the wound
full-thickness
full-thickness healing time ?
Takes longer, 1-2 cm/month
A 3-4 cm lower leg ulcer will take optimally 2-4 mos to close
Partial-thickness Wounds facts ?
If a wound is allowed to dry out, upper cell layers die and depth of injury extends
so
Keep wound occluded with a cream or polyurethane film – maintains moisture without eschar formation
______ is inelastic, putting shearing forces on underlying tissue during motion – painful
Eschar
Full-thickness Wounds facts ?
Historically – “leave it open to air”
But epithelial cells migrate significantly faster in moist environment
Dressings, creams
What can slow down cell migration during wound healing ?
Eschar
necrotic tissue
excess exudate
dry material
Epithelialization: Epithelium has no _______ , so it is sensitive to ______ and will ?
strength
Sensitive to shearing forces
Will blister or break down with trauma
Epithelialization: As it matures over months, it anchors to the dermis by______
fibers
Epithelialization: May appear different from surrounding skin due to ?
altered collagen and
any absence of hair or glands
Well-approximated wounds have epithelial cover by __ hours so okay to bathe…..unless ?
24
prosthesis or foreign
material in wound
Early washing helps to rid exudate, blood and bacteria
An open wound continuously releases exudate which is_______ to tissue so it can Get colonized and becomes a ____________
adherent
culture medium
Colonization and culturing of bacteria is improved with ?
Frequent dressing changes
Irrigation
Mechanical removal of
debris - debridement
Detergents
Sterile saline
Tap water better than a dirty wound
With cutaneous sutures, epithelium starts to migrate down suture track ________
immediately
If sutures are too tight or if there is swelling, suture will cut through the dermis – causing ?
“railroad tracks”
Remove cutaneous sutures within ______
1 week
So remove cutaneous sutures within 1 week
…. BUT tensile strength at 1 week is __ of normal
3%
Tensile strength at 3 weeks, it is ___ of normal
10%
Tensile strength at 6 weeks, it is ___-___ of normal
35-50%
Wound Strength: ______________- sutures help (last 3 weeks)
Subcuticular
Wound Strength: Wounds of abdominal fascia or tendons need to be protected for ______ (at 35-50% of normal by then)
6 weeks
Wounds over high tension areas need support for several weeks to allow ?
collagen remodeling and cross-linking
High tension wounds need support like ?
Steristrips
Wound immobilizers
Semiocclusive dressing
Silicone gel sheeting
Goal is to keep wound moist and absorb exudate
Wound Complications ?
Hematoma
Seroma
Dehiscence
Hematoma, patho, RF, and tx. ?
Collection of blood and clot
Higher risk in pts on ASA or low-dose heparin, coughing, HTN
Tx – evacuate the clot under sterile conditions, ligate, reclose
Seroma, patho, RF, and tx. ?
Fluid other than pus or blood
Mainly when lymphatics are cut
Compression dressing, vacuum device
Dehiscence definition ?
Partial or total disruption of any or all layers
___________ – all layers of abdominal wall with extrusion of abdominal organs
Evisceration
Wound dehiscence RF ?
*Inadequate closure - #1 reason
Increased intraabdominal pressure
Deficient wound healing
What is the #1 reason for wound dehiscence ?
Inadequate closure
Wound dehiscence tx. ?
Reclose using heavy gauge suture/wire
If due to infection – tx infection and delay
Options for Optimizing Healing ?
Regranex - GF (PDGF)
Apligraf - Artificial Skin Equivalents
Hyperbaric oxygen - Seems effective though no clinical trials
Electrical stimulation - By physical therapists
Growth factors – PDGF (Regranex) usually for ?
For diabetic foot ulcers
Artificial Skin Equivalents – Apligraf - usually for ?
Engineered skin for chronic wounds, venous ulcers
Factors that Impair Healing ?
Diabetes
Aging
Ischemia
Malnutrition or catabolic state
Edema
Radiation
Steroids or chemotherapy
Collagen vascular disease
________ is a common cause of fever after 3rd postop day
Phlebitis
A post-op fever is more likely infectious if ?
Preoperative trauma
Onset after the second post op day
WBC above 10,000
BUN above 15
Surgery class above a 2
Temp above 38.6
5 Ws of post op fever ?
Wind Wound Water Walk Wonder drugs
________ is the most common pulmonary postop complication
Atelectasis
Fever ______ in the immediate postoperative period (1st 48 hours) is usually due to atelectasis
<102
atelectasis PE ?
Decreased breath sounds, esp bases in a patient taking shallow breaths. CXR can confirm
atelectasis prevention anf tx. ?
deep breath, cough, ambulation
What decrease the tidal volume ?
Pain, anesthesia, analgesia
Pneumonia fever level and sxs. ?
102 fever,
confusion, hallucination, tachypnea, hypoxia, elevated WBC, purulent sputum
<102 in first 48 hours is usually atelectasis
Chemical pneumonitis patho ?
Aspiration of gastric contents
Chemical pneumonitis
RF ?
Elderly, chronically ill, pts with GERD, food in stomach, pregnant at higher risk
Chemical pneumonitis
tx. ?
supportive
Antibiotics only if the pneumonitis becomes a bacterial pneumonia (purulent sputum)
Most common nosocomial infection ?
UTI
indwelling foleys
If UTI develops, give empiric antibiotics until culture results are back, which organisms are you wanting to cover ?
E. coli
Klebsiella
Pseudomonas
Early fever, 1st 48 hours ?
Atelectasis
No work up needed, if patient is otherwise okay
Fever days __-__ could be infectious or not
2-5
Fever lasting after 5th day, what is much more likely ?
Wound infection
Signs and Symptoms of Infection, other ?
Fever, chills
Malaise, fatigue, loss of appetite
~N/V
Tachycardia, tachypnea
Hypovolemia
Sxs. of hypovolemia ?
Dry mucous membranes
Hypotension
Oliguria, concentrated urine, anuria
____________ – most appear during surgery or in first 3 postop days
Dysrhythmias
Postop MI - ____ of all patients
0.4%
Postop cardiac failure – ____ of pts over 40 yo, usually due to fluid overload
4%
Postoperative Parotitis ?
rare
staph infxn of parotid gland
Postop fecal impaction due to ?
colonic ileus
opioids
Postop fecal impaction
Dx, ?
rectal exam
Postop fecal impaction
tx. ?
manual disimpaction
then enema
Bowel obstruction due ?
paralytic ileus
mechanical obstruction
Bowel obstruction what to look for ?
Look for air-fluid levels in loops of small bowel
Fat embolism ?
Common but usually asymptomatic
Resp and neuro symptoms when severe
Hemoperitoneum ?
Rapid and life-threatening
Clostridium difficile colitis ?
Common nosocomial infection
Asymptomatic to severe
IV metronidazole or oral vancomycin
Postop pancreatitis ?
Usually after surgery near the pancreas
Often necrotizing type
Postop urinary retention ?
Inability to void, common, often due to over distention
Risk of UTI
Postop cholecystitis ?
After any surgery, but esp GI
Usually no stones and more common in men
Often becomes necrotic
CNS complications ?
Postop CVA
Seizures – esp patients with Crohn or UC
Postop CVA ?
Usually due to poor perfusion
Elderly with atherosclerosis, hypotensive
Psychiatric complications ?
“Postop psychosis”
“Postop psychosis” ?
On 3rd postop day, confusion, fear, disorientation
Rule out metabolic derangement, infection
