wound complications - Emily Flashcards
What affects wound healing?
-Wound factors
-Host factors
-External factors
What is the most significant complication to wound healing?
Bacterial infection
What are two ways bacteria can invade a surgical site?
- Local route (patient surfaces, instruments, surgeon, environment)
- Distant route (other site infection in patient, hematogenous spread)
What is the approximate risk of SSI in a clean wound?
1-5%
What is the approximate risk of SSI in a clean contaminated wound?
5-10%
What is the approximate risk of SSI in a contaminated wound?
10-30%
What is the approximate risk of SSI in a dirty wound?
> 30%
Which tissue types are involved in superficial SSI?
Skin and subcutaneous
Which tissue types are involved in deep incisional SSI?
Muscle and fascia
Which tissue types are involved in organ or space SSI?
Peritoneum, pleural space, etc
What is the infectious dose of bacteria?
> 10^5 bacteria/gram of tissue
What bacterial factors can affect the infectious dose needed?
-High microbe virulence (adherence, antibiotic resistance, biofilms)
-Foreign material in wound or site
-Host site dependent (oral mucosa and tissues or mouth vs synovial fluid or CSF)
What are important surgical risk factors?
-Duration of surgery (TIME)
-Aseptic technique
-Foreign material
-Surgical technique
-Emergency procedures
What are Halstead’s principles of surgery?
-Gentle tissue handling
-Hemostasis
-Preservation of blood supply
-Strict aseptic technique
-Minimize tension
-Accurate apposition of tissue
-Eliminate dead space
What are common symptoms of SSI?
-Fever, redness, swelling, pain
-Purulent discharge
-Wound dehiscence/delayed healing
-Usually within 30 days
What are some ways to prevent SSI?
-Careful skin prep
-Minimize trauma (ex. scalpel vs laser)
-Minimize trash
-Minimize surgical time
-Peri-operative antibiotics if indicated
What is prophylactic antibiotic use?
Given pre-operatively and possibly intra-op to prevent establishment of infection
What is therapeutic antibiotic use?
Used post-operatively when indicated to treat an established infection
When would it be a good idea to give prophylactic antibiotics?
-Fracture repair with implants
-Abdominal surgery
-“field” surgery
-Anything other than clean surgeries
What are the principles of administration of surgical antibiotics?
-Bactericidal (1 dose given 30 mins before surgery)
-Maintain levels throughout surgery (2nd dose if surgery is >3 hours or 1-2x 1/2 life of drug)
-Not necessarily needed >24hrs post op
What are routes of administration for antibiotics?
-Systemics (IM or IV)
-Regional (perfusion with tourniquet, antibiotic implants)
-Topical (tissue irrigation)
What are some procedures where prophylactic antibiotics would be a good idea?
-Long surgeries (>90mins)
-Prosthetic (permanent) implants
-Patients with prostheses undergoing surgery
-Severely infected or traumatized wounds
-Orthopedic surgeries
-Respiratory surgeries
-GI surgeries
-Urogenital surgeries
-Systemically compromised patients
What is dehiscence?
A complication of wound healing in which the wound ruptures along a previously closed surgical incision
What are some wound factors that can lead to dehiscence?
-Infection
-Excessive tension
-Seroma/hematoma formation (dead space)
-Non-viable tissue or poor perfusion
-Saliva or synovial fluid in wound
-Foreign body
-Neoplasia
What are some patient factors than can lead to dehiscence?
-Systemic disease
-Nutrition
-Medications
-Neoplasia
What are some environment factors than can lead to dehiscence?
-Post op wound trauma
-Movement
What are some signs of impending wound dehiscence?
-Discharge along suture line
-Excessive swelling or fluid accumulation under skin
-Evidence of suture failure
-Evidence of tissue necrosis
How many days post-op is dehiscence likely to happen?
7 days
How can you prevent wound dehiscence?
-Prevent contamination
-Minimize tension
-Immobilize joints to minimize movement
-Reduce dead space
-Reduce swelling
-Protect from trauma
-Overall patient care (meds, nutrition)
What are some things you would do to work up a wound that isn’t healing well?
-Impression smears and culture
-Biopsy and culture
-Radiographs
-Wound exploration
What are some factors that contribute to delayed wound healing?
-Foreign body
-Reduced local blood flow
-Systemic factors (diseases)
-Drugs (corticosteroids, chemotherapy, etc)
What is a bone sequestrum and which species is it most common in?
A piece of dead bone in the wound. Most common in horses
What causes a bone sequestrum?
-Loss of blood supply in periosteum
-Bacteria invade and colonize dead bone
Why does a bone sequestrum impair healing?
It acts as a foreign body and provides a place for bacteria to thrive
What are some signs that a bone sequestrum might be present?
-Persistent soft tissue swelling
-More pain than expected with palpation
-Mild lameness
-Persistent cleft in granulation tissue
-Persistent drainage
-Wound won’t heal
When is a bone sequestrum likely to occur?
3-4 weeks after initial injury
What are 3 types of excessive wound healing?
-Fibroproliferative wound healing
-Contracture
-Adhesions
What is fibroproliferative wound healing?
-Exuberant granulation tissue (proud flesh) - OPEN
-Hypertrophic scar/keloid - CLOSED
What type of wounds are at high risk of excessive wound contracture?
-Large wounds
-Wounds in high motion areas
-Wounds left to heal by second intention
What can excessive wound contracture lead to?
Impaired function, pain and disability
What are some ways to treat/prevent excessive wound contracture?
-Primary closure or delayed primary closure when possible
-Reconstructive techniques
-Physiotherapy
-Scar revision procedures as treatment
What is tissue adhesion?
Scar formation and contracture affects internal organs or tissue in a pathologic manner
How can the risk of tissue adhesion be reduced?
-Good surgical technique and tissue handling
-Anti-adhesion products for intraoperative use
-Physiotherapy
What is exuberant granulation tissue?
Excessive and prolonged proliferative phase where granulation tissue extends above epithelial margins
What are consequences of granulation tissue above epithelial margins?
-Inhibits epithelialization and contraction
-May cause expansion or enlargement of wound
What are treatment options for excessive granulation tissue?
-Surgical excision
-Local anti-inflammatories
-Reduce inflammatory stimuli
-Possibly a bandage
-Skin grafting
What are the 4 main wound healing complications?
-Infection, SSI
-Delayed wound healing (dehiscence)
-Bone sequestrum
-Excessive wound healing
