Surgical Infections Flashcards
T/F: Most surgical infections are polymicrobial (anaerobes and aerobes).
True
A class of relationship between two organisms where one organism benefits without affecting the other.
Commensalism
Host Defenses
- Skin and mucosa
- Microflora
- Mucus
- Stomach pH
- Lactoferrin and Iron Chelators
- Complement System
- Innate Immune System (macrophages)
- Adaptive Immune System (T cells, B cells)
- Omentum
Why is surgical infection a growing problem?
- Emerging Resistant Organisms
- Changing patient population – sicker patients, immunosuppressed patients
- Larger, more invasive procedures – Sx implants
For any given operation, the development of a wound infection will approximately ______ the cost of hospitalization.
Double
Systemic Manifestations of Infections
- Local Manifestations
- Fever (385 deg Celsius/ Immunosuppressed patients)
- Elevated WBC
- Tachycardia
- Tachypnea
- Altered Mental Status
What are the possible outcomes of a microbial invasion?
- Eradication
- Containment (i.e. abscess, pus, intermittent drainage)
- Locoregional Infection (i.e. cellulitis, lymphangitis, agressive soft tissue infection
- Metastatic Abscess
- Systemic Infection
Examples of Soft Tissue Infections
- Cellulitis
- Necrotizing Infection
Examples of Body Cavity Infections
- Peritonitis
- Intra-abdominal abscess
- Empyema
Examples of Hospital-acquired Infections
- Wound Infections
- UTIs
- Pneumonia
- Catheter-related
Term for a surgical complication in which a wound ruptures along surgical suture.
Dehiscence
An _______ removes the internal contents of the eye and leaves the sclera to prevent spread of the infection?
Evisceration
This is a localized or diffuse inflammation of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin.
Cellulitis
This is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies (necrosis). This can be wet or dry (wet is more serious)
Gangrene
This is a collection of pus in any part of the body that, in most cases, causes swelling and inflammation around it.
Abscess
This is the presence of bacteria in the blood.
Bacteremia
This is a potentially fatal whole-body inflammation (a systemic inflammatory response syndrome or SIRS) caused by severe infection.
Sepsis
Risk Factors for a UTI
- Instrumentation (Foley)
- Elderly or debilitated
- Pregnancy
- Urologic Abnormalities
What should you do with a Foley cath?
Use it only when necessary and only as long as necessary.
Pneumonia is more common when there is a _________.
Inhibition of normal cough, such as with anesthesia, narcotics, pain, or ET intubation
Signs of Pneumonia/Recumbency
- Excess fluid accumulates at lung bases (atelectasis)
- Decreased breath sounds, crackles
- CR Findings
- Hypoxia
How do you prevent pneumonia?
- Early extubation
- Incentive Spirometry/ Chest PT
- OOB
- Oropharyngeal decontamination with topical antibiotics
- Limit Narcotics
Best treatment for a pneumonia
Abx
Common IV Catheter-related infections
S. aureus
S. epidermidis
Risks of IV Catheter-related infections
- Duration of catherization
- Number of catether manipulations
- Violations of catether manipulations
- Multi-lumen catheters
- Transparent dressings (vs. simple gauze)
How do you diagnose an IV Catheter-related infection?
- Frank pus around catheter site
- Cellulitis around catheter insertion
- Culture of blood from catheter
How do you treat an IV Catheter-related infection?
- Remove catheter
- Culture blood (not catheter tip)
- Catheter Free Break
- Abx
- Reinsert New Line
Patient Related Risk factors for surgical infection
- Pre-op admission
- Concomitant infection
- DM
- Obesity
- Age
- Immune Response
- Abdominal Sx
- Malnutrition: Albumin > 2.5, Prealbumin
- Smoking
- Ischemia
- Nasal Carrier
- Chemo/Radiotherapy
- Steroids/Immunosuppressive
Perioperative Risk factors for surgical infection
- Abx prophylaxis
- GI preparation
- Surgical time
- OR ventilation/personnel traffic
- Hair Removal
- Foreign Material
- Patient Scrubbing
- Steilization Techniques
- Drains
- Antisepsis
- Blood transfusion
- Surgical Scrubbing
- Surgical Technique (Burn, Hemostasis, Trauma)
How can you prevent surgical infections?
- Improve patients general health
- Operative Technique
- Preoperative Abx
- Preop showering with antimicrobial soap
- Skin antiseptics
- Washing and Gloving
- Sterile Drapes
- Gowns and Masks
Surgical Hand Hygiene can also prevent surgical infection. How?
- Preop washing to the elbows
- Using antiseptic soap
- Using Aqueous Alcohol
- **Hand rubbing and hand scrubbing have similiar SSI rated.
- **Hand rubbing better tolerated and more complications
How does abx prophylaxis prevent surgical infection?
- Eradicate/retard the growth of endogenous organisms
- Must be within a 1 hour window prior to incision time
- Most clean procedures do no require it, but CABG, Prosthesis, Laminectomy
What are the common abx used for abx prophylaxis in Abx Prophylaxis?
- Cefazolin – most clean procedures
- Cefuroxime – Thoracic and Ortho Sx
- Cefotetan (Cefazolin/Metro) – Bowel Sx
- Timentin – Appendectomy, Biliary Tract Sx
- Clindamycin or Levo – PCN allergy
- Vancomycin – Prevent MRSA in centers with high prevalence, prosthetic valves and vascular grafts, hx of broad-spectrum abx therapy, preoperative stay longer than 1 week in the hospital.
When should you give prophylactic abx?
Within 1 hour (30 min window)
When do you redose antibiotics?
- Every 1 half life (not routinely
- Indication: > 4 hours, Major Blood loss
- D/c within 24 hours or 48 if cardiac
Surgical Prevention in Colorectal Surgery:
- Preop IV antibiotic prophylaxis
- Bowel Preparation ABx (Oral neomycin + erythromycin/metro)
- Bowel Mechanical Prep: Golytely, Magnesium Citrate, Phospho-soda
How do we decontaminate the nose as a preventative measure?
- Intranasal Mupirocin
2. Intranasal chlorhexidin fluconate to reduce in MRSA carriage. No data on this
Hair removal is a surgical infection prevention method.
Shaving increases SSI, so remove it just prior to incision using clippers or creams, if you need to.
Shaving is allowed for skin grafts.
How do we prevent complications with hyperglycemia?
- Tight glucose control below 150 mg/dL
- Continuous IV insulin decreased SSI and bette than SQ
- Each 50 mg/dL above nl increased NHS
Vasocontrictive response can lead to what?
Skin ischemia
What temperature should the OR be at to reduce the risk of SSI?
36.5 Celsius +
This is the term used for tissue loss at the skin caused by a traumatic or surgical incision.
Wound
This is a term used for infections related to the operative procedure that occurs at or near the surgical incision within 30 days or within a year if an implant is left.
Surgical Site Infection
How do you classify SSI?
- Incisional (Superficial vs. Deep)
2. Organ/Space
Which type of SSI is more serious/expensive?
Organ/Space
This is a type of SSI that is involves the skin and SQ tissue and at least one of the following:
a. Purulent drainage
b. Wound opening by surgeon
c. Positive Culture
d. Surgeon’s Dx
Incisional Superficial SSI
Exclusion criteria for Incisional Superficial SSI
- Suture Abscess
- Infected Episiotomy
- Infected Neonatal Circumcision
- Infected Burn
This is a type of infection that involves the deep soft tissues, fascia, and muscle of an incision and at least one of the following:
a. Purulent Drainage
b. Fever >38 deg C
c. Spontaneous or intentional wound opening, pain, and localized tenderness
d. Visual, radiographical or histological evidence of an abscess
e. Surgeon’s dx
Incisional Deep SSI
This is an infection that involves any part of the anatomy that was manipulated and at least one of the following:
a. Purulent drainage from the organ or space
b. Positive culture
c. Visual, reoperative, radiological or histopathological evidence of organ/space infection
d. Surgeon’s dx
Organ/Space SSI
Degrees of Contamination:
- Clean
- Clean - contaminated
- Contaminated
- Dirty
Why is it important to know the degree of contamination?
- Estimate the risk of SSI
- Identify potential pathogens
- Establish the need of prophylasctic abx
- Decide type of closure and post-op care
***Poor predictors of overall risk for SSI!!!!!!
Describe a clean or class I type of wound.
- Surgical procedure with prepped skin
- Not infected
- No pre-existing skin inflammation
- No resp, GI or GU tract involvement
- Primary Closure
Example of Clean Wound?
- Hernia
- Thyroidectomy
- Vagotomy
- Neurosurgery
Describe a clean-contaminated or class II type of Wound.
- Respiratory, GI, or GU tract
- Mechanical and antibacterial preparation
- No evidence of an active infection
- Minor sterile technique errors
Example of Clean-Contaminated Wound?
- Cholecystectomy
- Appendectomy
- Colonic Resection
- Adenoidectomy
Describe a contaminated or class III type of wound.
- Acute non-purulent inflammation
- Traumatic open wound
- Major failure in sterile technique (emergent open massage)
- Significant GI leak (Colonia, biliary..etc)
- Secondary or delayed primary closure
Example of Contaminated Wound?
- Gangrenous Cholecystitis
- Enterotomy
Describe a dirty or class IV type of Wound.
- Old traumatic would (>6 hrs)
- Necrotic or infected wound
- Hollow organ perforation
- Active infection
- Delayed closure
Example of Dirty Wound?
- Perforated Appendicular Abscess
- Perforated Diverticulitis
- Infected Mesh
Risk of infection for a clean wound? Common agent?
1-3%; S. aureus/epidermidis
Risk of infection for a clean-contaminated wound? Common agent?
2.4-7.7%; Endogenous flora
Risk of infection for a contaminated wound? Common agent?
6.4-15.2%; Endogenous flora
Risk of infection for a dirty wound? Common agent?
7.1-40%; Mixed agents
What is acute care management for a surgical infection?
- Resuscitate
- Open Wound
- Obtain cultures from deeper wounds
- Abx Therapy
What is long-term care management for a surgical infection?
- Improve patient condition (DM, immune status)
- Standard versus moist therapy
- Wound VAC (vacuum assisted closure)
Classifying a wound by color! What would yellow indicate?
Dirty
Classifying a wound by color! What would green indicate?
Infected
Classifying a wound by color! What would pink indicate?
Epithelialized
Classifying a wound by color! What would black indicate?
Necrotic
Classifying a wound by color! What would red indicate?
Granulated
What is the regular therapy for a wound?
- Saline
- Gauzes/Pads
- Soap, iodine, vaseline
- Frequent changes (q 4-6 hours)
- Tape
Side Effects of Regular Therapy:
- Contact Dermatitis
- Skin Damage
Moisture Therapy!
- Moisture Keepers (Opsite/Tegaderm; Hydrocolloids, hydropolymers hydraocellular)
- Debridement agents (hydrogels; calcium/collagen alginates; Activated charcoal/silver alginates; collagenase)
Side Effects of Moist Therapy:
- Bleeding
- Hypergranulation
- Skin maceration
- Allergic Reactions
