Midterm Flashcards
(197 cards)
1.Approach to the Surgical Patient
- Chief complaint
- History of present illness
- pain
- vomiting
- change in bowel habits
- hematemesis,rectal bleeding
- trauma
- Past Medical history
- drugs,ROS
- Past surgical history
- OB/GYN history
- Social and family history
1.1.Approach to the Surgical Patient
- Physical examination
- Elective surgical examination
- Examination of body orifices
- <c>ABCDE
<ul>
<li>
<strong>C</strong>atastrophic Haemorrhage control</li>
<li>
<b>A</b>irway (cervical spine control when appropriate)</li>
<li>
<strong>B</strong>reathing</li>
<li>
<b>C</b>irculation</li>
<li>
<strong>D</strong>isability</li>
<li>
<strong>E</strong>xtremity-environment-exposure</li>
</ul>
</c>
1.2.Approach to the Surgical Patient
- Provisional diagnosis
- most probable diagnosis so far
- Differential diagnoses
- list of probable diagnoses to rule out
- Lab & other studies
- blood tests
- urine tests
- functional studies : ECG etc
- Imaging test
- X-ray
- ultrasound
- CT,MRI
- Special investigations
- colonoscopy
- angiography
- cytoscopy
2.Types of Healing
Primary healing (first intention)
- Tissue is clean
- Reapproximation with sutures
- Healing without complication, minimal scarring
Secondary Healing (second intention)
- Infected wounds & burns
- Open wound
- Formation of granulation tissue
Delayed primary closure (third intention)
- Secondary healing for 5 days
- Then primary closure
3.Granulation Tissue
- Red,moist,granular tissue
- Appears during healing of open wounds
- Microscopy : collagen, new blood vessels, fibroblasts, inflammatory cells
- Healing achieved by creation of scar tissue
4.Wound Healing
Hemostasis & Inflammation
- 0-5th day after injury
- Platelet aggregation to exposed subendothelial collagen (IGF-1,TNFa,b, PDGF)
- Coagulation cascade: fibrin clot⇒ coagulation &scaffolding
- Chemotaxis : Damaged endothelial cells ⇒ activation of complement components
- Inflammatory cells :
- Neutrophils & monocytes 24-48h : rolling and adhesion
- Macrophages 48-96h
- T-lymphocyes peak at 7 days
4.1.Wound Healing
Proliferation
- 4-14 days
- Fibroblast replication
- Platelets release PDGF,IGF-1,TGFb
- Macrophages and fibroblasts release FGF,IGF-1,VEGF,IL-1,2,8, PDGF, TGFa,b
- Fibroblasts produce collagen and proteoglycans
4.2.Wound Healing
Angiogenesis
- 2nd to 4th day after injury
- Response to chemoattractants from platelets and macrophages
- PDGF,FGF,TNFa,b,VEGF
4.3.Wound Healing
Epithelization
- starts from wound edges
- Low PO2⇒TGFb from epithelial cells⇒blocks differentiation and promotes mitosis
- Wound needs to be moist to promote epithelization
- Exudate contains : growth factors and lactate
4.4.Wound Healing
Maturation & Remodeling
- 8d-months
- Fibroblasts replace fibrin ECM with collagen monomers⇒polymerization and cross-linking
- ECM evolution : fibronectin, collagen III,glycosaminoglycans,proteoglycans,collagen I
- Remodeling⇒collagen lysis and turnover (MPPs)
- Collagen deposition>>collagen lysis
- Fibroblasts attach to collagen fibres⇒wound contraction
- Negative effect of contraction⇒deformation,stricture
- Wound stretching if tension>>contraction
4.5.Wound Healing
Completion of Healing
- Lactic acidosis and hypoxia normalization⇒stopping of healing
- Keloids : hypertrophic scars due to local overgrowth of CT
Impaired healing
- inadequate inflammatory response : corticosteroids,immunosuppressants,chemotherapeutic drugs
- Excessive inflammation
- Malnutrition (weight loss,hypoalbuminemia)
5.Healing of Specialized Tissues
Bone
- Inflammation
- Proliferation : specialized granulation tissue (fibrocartilaginous callus)
- osteoclasts
- osteoblasts
- chondroblasts
- Bone remodeling
5.1.Healing of Specialized Tissues
Nerve
- Brain⇒CT scar
- Peripheral nerves⇒sheath&axon regenerates from the nerve cell but reconnects randomly distally
5.2.Healing of Specialized Tissues
Intestine
- 4-7th day : risk of anastomotic leakage
- Strength regained in a week
- Peritoneal adhesions
*
6.Factors Affecting Wound Healing
- Systemic
- Age
- Nutrition
- Smoking
- Metabolic diseases(DM,Metabolic syndrome)
- Drugs: corticosteroids,immunosup,chemo
- CT disorders - Ehler-danlos,marfan syndromes
- Local
- Hypoxia
- Mechanical injury
- Infection
- Edema
- Irradiation
- Ischemia
- Foreign bodies
7.Chronic Wounds &Ulcers
Decubitus ulcers
- prolonged pressure⇒tissue ischemia
- prolonged contact with moisture,urine,feces
- malnutrition
- in immobile,elderly,operated patients
- Treatment:
- drainage of infected space
- excision of necrotic tissue
- musculocutaneous flap
7.1.Chronic Wounds & Ulcers
Venous Ulcers
- poor perfusion and perivascular leakage of plasma
- lower leg
- Treatment: compression stocking,surgical treatment of vein insufficiency
Ischemic Ulcers
- Lateral ankle and foot
- Treatment: revascularisation,hyperbaric oxygen
7.2.Chronic Wounds & Ulcers
Diabetic Ulcers
- Neuropathy⇒trauma
- Microangiopathy⇒ischemia
- Treatment: protection of the ulcer,revascularisation
Treatment of wounds & ulcers
- Control infection w/ antibiotics
- Treat underlying circulatory disease
- Keep wound moist
- Debridement of unhealthy tissue
- Reduce autonomic vasoconstriction
8.Excess Healing
Excess dermal scarring
- Hypertrophic scar if epithelization takes longer than 3-4 wks
- Keloid
- 3 months after surgery
- keloidal fibroblasts synthesize 20x
- treat with local steroid injection
Peritoneal scarring(adhesions)
- Fibrin,fibroblasts &collagen⇒filmy adhesions
- Fibrinolysis w/in a week
- Migration of capillaries,nerves,CT⇒solid adhesions
9.Wound Management
Classification
- I.Clean:
- uninfected,no inflammation
- elective surgical wounds
- e.g.hernia,breast surgery
- management: primary closure
- Infection rate : <2%
- II.Clean-contaminated:
- Minor and brief contamination,minor inflammation
- Clean and sharp with local damage
- e.g.gastric surgery
- management: primary closure and wound cleaning
- infection rate : 1-5%
9.1.Wound Management
Classification
- III.Contaminated:
- Contamination apparent and prolonged,major inflammation
- Ragged and contused wounds w/ gross local damage
- E.g. inflamed appendectomy,penetrating wounds
- management: copious irrigation,debridement and primary closure
- infection rate : 5-25%
- IV.Dirty:
- Gross contamination w/ infection
- Old traumatic wounds >12h
- Severe tissue damage and excessive ischemic tissue
- e.g. abscess,perforated bowel
- management healing by secondary intention
- infection rate : 50%
10.Assessment of Wound Mechanism
- Kinetic energy injury -closed -blunt
- Kinetic energy injury-open-penetrating
- low energy -knife
- high energy - bullet
- Thermal injury
- Heat
- Frost
- Chemical injury
- Electrical injury
11.Surgical Management of Wounds
- Wound evaluation :
- mechanism of injury
- extent of injury and wound type
- decision for wound closure
- Patient consent
- Antimicrobials : tetanus prophylaxis
- Wound prep and sterile field
- Anesthesia
- Debridement-washing
- Hemostasis
- Closure
- Dressing
12.Other skin closure options
- Adhesive tapes
- (+) rapid, simple, no risk of needle injury
- (-) needs dry skin,poor adherence,poor hemostasis,accidental removal
- Skin glue
- (+) rapid,simple,reduced pain,good aethetic result
- (-) poor approximation of deep layers,poor hemostasis
- Surgical skin staples
- (+) fast closure of large wounds,less rxn than sutures
- (-) poor hemostasis


























