Wound Stuff (Cav)-Exam 1 Flashcards
1
Q
What type of wound has no infection and asepsis was maintained?
A
Clean wound
2
Q
What type of wound deals with a hollow organ but no bacteria contamination involved or there was a minor break in asepsis?
A
Clean-contaminated
Ex: foreign body retrieval
3
Q
What type of wound deals with a hollow organ that has open and spilled or a major asepsis break occurred?
A
Contaminated
Ex- BITE WOUND
4
Q
What type of wound contains pus or contents of perforated organ implying infection?
A
Dirty
5
Q
Define asepsis
A
minimize incidence of sx wound infection
6
Q
What is the relationship of time and risk in surgery?
A
Risk doubles every hour in sx- TIME IS TRAUMA
7
Q
What are the three risk factors for infection?
A
- duration of sx
- increasing number of persons operating
- dirty sx site
8
Q
What are the six risk factors contributing to infection/inflammation?
A
- duration of anesthesia
- duration of postop stay
- wound drainage
- Increased patient weight
- dirty sx site
- antimicrobial prophylaxis
9
Q
What is the most common source of operating wound infections?
A
Patients’ endogenous flora- GI/skin
10
Q
What is the difference of prophylactic and therapeutic antibiotic use?
A
Prophylactic: administration of Ab PRIOR to wound contamination/creation of wound
Therapeutic: infection already present
11
Q
What is the minimum time that Ab should be administered prior to sx?
A
30 minutes before (not longer than24 hrs.)
12
Q
How can postoperative infections be minimized?
A
Good nursing care- incision lines protected, wash hands/glove up between patients, remove catheters and drains in a timely manner
13
Q
What is the lag phase of wound healing and when does it occur?
A
First 3-5 days
Inflammation & debridement predominate and wounds have not gained much strength
14
Q
What are the four phases of wound healing?
A
- Inflammatory phase
- Debridement phase
- Repair
- maturation/Remodeling phase
15
Q
When does the inflammatory phase occur?
A
Within minutes of injury
16
Q
inflammation is a positive response that is initiated by what?
A
Tissue damage
17
Q
What are some examples of cellular response in the inflammatory phase?
A
Increased permeability of blood vessels, recruitment of circulatory cells, release of growth factors & cytokines and activation of WBC
18
Q
What is the first response to injury?
A
Hemorrhage
19
Q
What process controls hemorrhage with a fibrin clot (glues edges of wound together)
A
Vasoconstriction
20
Q
What process dissolved plug in lymphatics turning clot into a scab?
A
Fibrinolysis
21
Q
What process increases permeability causing a release of inflammatory mediators
A
Vasodilation
22
Q
What initiates the debridement phase?
A
Leakage of WBC into wound
23
Q
Where does the debridement phase occur?
A
In the wound bed when neutrophils and monocytes arrived
24
Q
What prevents infections and phagocytize organisms and debris?
A
Neutrophils
25
What cell is ESSENTIAL for wound healing?
Monocytes
| Lymphocytes/neutrophils are NOT essential
26
What do macrophages secrete?
Collagenases- removes necrotic tissue, bacteria, and foreign material
Chemotactic factors- direct macrophages to injured tissue
Growth factors- initiate, maintain & coordinate formation of granulation tissue
27
What occurs in the repair phase?
Macrophages stimulate fibroblast & DNA proliferation
28
What type of environment do fibroblasts prefer?
Acidic and oxygen rich environment
29
What is angiogenesis?
Capillaries infiltrate wound under fibroblasts- relies on interaction of extracellular matrix w/ cytokines
30
What is formed with the combination of fibroblasts, new capillaries and fibrous tissue development 3-5 days post wound?
Granulation tissue
31
What are the functions of granulation tissue?
Barrier to infection
External source of special fibroblasts
Surface for epithelial migration
32
What is epithelialization?
Mobilization, proliferation & differentiation of epithelial cells
33
What is the time period of epithelialization for sutured wounds vs. opened wounds?
Sutured wounds: 24-48 hrs
| Open wounds: 4-5 days
34
T/F: Migration of epithelial cells is random but guided by collagen fibers
TRUE
35
What is the term for when there is contact on all sides w/ other epithelial cells inhibiting further cell migration?
Contact inhibition
36
What environment does fast epithelialization occur in?
Moist
37
T/F: Oxygen rich environment prevents epithelial migration and mitosis
FALSE- anoxic environment
38
What type of bandages delay re-epithelialization?
wet-to-dry bandage
39
What is wound contraction?
size of wound reduced from fibroblasts, reorganizing collagen in granulation tissue & myofibroblast contraction at the wound edge
40
What does wound contraction occur simultaneously with?
Granulation & epithelialization
41
What is necessary for initiation of contraction?
Fibroblastic invasion
42
What is contraction inhibited by?
skin around wound being fixed, inelastic, under tension or when myofibroblasts are inadequate
43
When does the maturation phase begin?
Once adequate levels of collagen are reached (17-20 days post injury)
44
What type of collagen fibers increase vs. decrease?
Increase- Type I
| Decrease- Type III
45
When does the most rapid gain in wound strength occur?
Between 7-14 days post injury b/c of rapid collagen accumulation
46
T/F: Normal tissue strength is regained months after inury
FALSE- never regained. Only about 80% strength is regained
47
What class of wound has minimal contamination or tissue damage?
Class I- 0-6 hrs. post wound
48
What is the golden period?
insufficient microbial replication to cause infection and can manage with primary closure
49
What class has microbial replication to critical level possible and at what time frame is this seen?
Class II- 6-12 hrs. post wounding
50
What class does microbial replication at critical level allow for infection?
Class III- >12 hrs. post wounding
51
What type of wounds will receive primary closure?
Class 1 & some 2 wounds
52
What is delayed primary closure and what class is associated with this?
```
Appositional closure before granulation tissue develops
Good for class 2 wounds
```
53
What is secondary closure?
Appositional closure after granulation tissue has developed
54
What is second intention healing?
Healing by contraction/epithelialization or open wound management
55
What are the 8 fundamentals of wound management?
1. Assess patient
2. Prevent nosocomial infections
3. Aseptically clip/scrub area
4. Lavage
5. Procure culture of wound
6. Debridement
7. Select appropriate surgical closure method
8. Provide drainage if necessary
56
T/F: Scrub the area around and the wound itself
FALSE-only scrub around the wound- can cause irritation, toxicity, pain and potentiate wound infection if scrubbed inside wound
57
Why should alcohol never be used on open wounds?
Damages open tissue
58
How does lavage reduce bacterial numbers?
loosening and flushing bacteria and associated necrotic debris away
59
What is the preferred lavage solution?
Sterile isotonic saline or balanced electrolyte solution
60
T/F: Antiseptics have little effect on established infection
TRUE
61
What should be used for initial cleaning of heavily contaminated wounds?
Running, luke worm tap water
62
What is a potential disadvantage of tap water when dealing with wound cleaning?
Causes hypotonic tissue damage
63
What is the goal of lavage?
Remove particulate debris/bacteria w/ mechanical contact, inertial force and exudate infected wounds and remove toxins associated with infection
64
What is the ideal lavage pressure?
7-8 psi
65
When should your wound culture be taken?
initial debridement- preferred
66
What are the most common organisms that cause infection?
Staph and E. coli
67
What type of cultures should be requested in heavily contaminated wounds?
Aerobic/anaerobic
68
What type of wounds is topical antimicrobials use?
Open wounds-applied in 1-3 hrs. of contamination infection is prevented
69
What route of antimicrobials would be used for heavily contaminated wounds?
Topical/systemic antimicrobial therapy
70
What prevents topical Ab from reaching effective levels in tissues deep in the wound and prevents systemic antibiotics from reaching superficial bacteria?
Wound coagulation
71
What must be performed to allow Ab access to bacteria in wound?
Wound debridement
72
Which topical antimicrobials are used for superficial skin wounds?
Bacitracin, neomycin & polymyxin
73
Which bacteria do topical antimicrobials have poor efficacy against?
Pseudomonas spp.
74
Which topical antimicrobial can retard wound contraction?
Zinc bacitracin
75
What topical antimicrobial is effective against most gram +/- and fungi?
Silver sulfadiazine
76
What is the drug of choice used to treat burn wounds?
Silver sulfadiazine
77
What is the process of removing dead/damaged tissue, foreign material & microorganisms from wound?
Debridement
78
What are the two types of surgical debridement?
Layered and En bloc
79
What is the difference of layered vs. en bloc debridement?
Layered: devitalized tissue sx excised in layers beginning from surface and progressing into wound
En bloc: entire wound can be excised if sufficient healthy tissue surrounds the wound & vital structures can be preserved
80
What is the advantage of en bloc debridement?
Wound care greatly accelerated
81
What must you be careful of in terms of cats and debridement?
Don't take extensive SQ in cats as it may delay wound healing
82
What is the difference of autolytic and biosurgical debridement?
Autolytic: creation of a moist environment to allow endogenous enzymes to dissolve nonviable tissue
Biosurgical: maggot therapy using greenbottle fly larvaeas the maggots secrete proteolytic digestive enzymes into wound
83
What is autolytic debridement highly selective for?
Devitalized tissue ONLY
84
Why is fluid accumulation detrimental to wounds?
Acts as a growth medium for bacteria, separates tissue planes that should be healing together, creates pressure leading to pain and decreased blood flow
85
What are the two classifications of drains?
Active and Passive
86
How does a penrose drain operate?
Relies on gravity dependent flow of fluid in dead space
87
T/F: Fluid travels through a penrose drain?
FALSE- flows on either side of it, no need to fenestrate the drain
88
How long should a drain be left in typically?
5-7 days-longer risks infection
89
Where should drain exit sites be placed?
most dependent area of dead space at least 1 cm from wound
90
Why shouldn't the drain exit through the primary incision line?
increases risk ofwound dehiscence
91
Why should cold compress be avoided in the wound?
Freezes fluid in wound
92
What is the gold standard active drain?
Jakson pratt
93
How does the jackson pratt drain work?
Relies on concept of active removal of wound fluid w/ negative suction-complete seal needed to create suction
94
T/F: No need to make fenestrations with a Jackson Pratt drain
FALSE- fluid travels in the drain-relies on fenestrations
95
What is the difference of the exit site of a Jackson Pratt drain as opposed to a penrose drain?
Jackson pratt drains exit dorsal to wound in NON-DEPENDENT portion of wound
96
What is a major advantage of the Jackson Pratt tube?
quantification of drain production at home
97
How much fluid does the body produce as a reaction from the drain?
1-2 mL/kg/day
98
At what rate of drainage should you remove the drain?
Decreased below 5 mL/kg/day= < 0.2 mL/kg/hr
99
What is the most common problem of active drains?
Loss of suction during healing- make sure grenade is securely attached to tube and evacuation port is closed (common problem)
100
What is the first step of open wound management?
Debridement-removes all contaminants
101
What is the most selective type of debridement?
Autolytic debridement- spares healthy cells by only targeting necrotic/damaged tissue
102
What is the least desired form of debridement?
Mechanical debridement (nonselective)- physical removal of tissue adhered to a dried on dressing
103
What are the three layers of bandages?
Primary (contact) layer (sterile)
Intermediate (secondary) layer (non-sterile)
Outer (tertiary) layer (non-sterile)
104
What is the adherent layer used for?
Mechanical debridement of necrotic tissue and debris and absorption of wound exudate
105
When is non-adherent bandage used?
When granulation tissue has formed but current wound care standards recommended use of hydrophilic nonadherent contact layers for all wounds
106
What is the most commonly used bandage in veterinary medicine?
Semi-occlusive
107
Wet-to dry and dry-to-dry bandages are examples of what type of bandage?
adherent bandage
108
Telfa, adaptic, hydrogels and hydrocolloids are examples of what type of bandages?
Non-adherent bandage
109
T/F: once granulation tissue has formed you can still use wet-to-dry bandages?
FALSE- only used in early wound management
110
What kind of debridement does wet-to-dry bandage use?
Mechanical debridement- moving away from these bandages
111
___ MVTR strongly correlates w/ positive wound healing outcome and predictive of healing
Low MVTR (moisture vapor transmission rate)
112
What should bandages be covered with?
3-layer modified Robert Jones
113
How often should bandages be changed during the inflammatory phase?
Q2-3 days
114
How often should bandages be changed once granulation tissue has formed?
Q5-7 days
115
What are three different substances used in open wounds?
Manuka honey, sugar and low-level laser therapy
116
What pressure increases blood flow to a wound, accelerates rate of granulation tissue formation, decreases bacterial counts &improves flap survival?
125 mmHg NPWT
117
When are negative pressure wound therapy used?
Large open & effusive wounds devoid of granulation tissue; chronic non-healing wounds, postop mgt of tissue flaps, open abdominal mgt for septic abdomen
118
T/F: Not all bites are considered contaminated
FALSE- all bites are contaminated wounds
119
Why are all bite wounds considered contaminated?
contain polymicrobial flora reflecting the flora of the oral cavity of biter, skin of victim and environmental pathogens
120
What is the most common pathogen cultured from bite wounds?
Pasteurella multocida
121
What kind of injury is caused by a K9 dog bite?
Crushing, tearing and avulsion injury
122
What is the iceburg effect?
appearance of wound doesn't look bad but the damage underneath is extensive
123
Where do bites occur in large breed dogs vs. small dogs?
Large breed dogs: neck & face
| Small breed dogs: dorsum
124
Cat bites have more of puncture wounds, what concern rises from that?
Higher risk of infection
125
Cervical injuries have risk for damaging what leading to what two major side effects?
trauma to trachea potentially leading to pneumomediastinum w/ potential for respiratory embarrassment
126
What should always be done when a patient is presented with thoracic and abdominal wounds?
Radiographs to ensure penetration into a cavity hasn't occurred
127
Why are drains not needed in the head and extremities?
Natural drainage due to gravity
128
What confirms abdominal penetration?
Free peritoneal air, visible hernia- always explore and probe wound
129
What is required in a patient IMMEDIATELY when presented with abdominal bite wounds?
Immediate exploratory laparotomy
130
What is the term for when heat energy is applied at a faster rate than tissue can absorb &dissipate?
Thermal injury= coagulative necrosis & irreversible skin damage
131
What is the recommended source of heat in veterinary practice for patients?
HotDogTM- circulates warm water in a mat
132
What type of burn involves the outermost epidermis and typically heals spontaneously within 3 weeks via epithelialization?
1st degree burn
133
What type of burn involves full thickness epidermis & dermis, non-painful and dark brown in color?
3rd degree burn
134
what type of burn involves the epidermis and a portion of the dermis, painful and can spontaneously re-heal but takes months?
2nd degree burn
135
Burns involving <15% TBSA require what?
Minimal supportive therapy
136
Burns involving >20% leads to what?
Greater risk of systemic effects
137
Burns involving >50% may warrant what?
Euthanasia
138
When managing wounds, how should the hair be clipped?
WIDE- to ensure that there are no underlying bruises, small wounds or cuts under hair
139
What is the best protection agains wound colonization & infection?
Silver sulfadiazine
140
When are degloving injuries commonly seen?
limb caught beneath a car tire and dragged- typically involving the tarsocrural joint
141
What results from injury of collateral ligament or fracture of medial or lateral malleolus?
Subluxation
142
What results form injury of both medial & lateral collateral ligament complexes, fracture of both malleoli or fracture of one w/ injury to contralateral collateral ligament complex
Luxation
143
What type of wound closure is always the ideal choice?
Primary wound closure
144
What are the six goals of wound closure?
```
Minimal tension
full return to function
pain-free final outcome
cost effective
acceptable cosmesis
satisfied owner
```
145
What are the Halsted Principles?
```
Gentle tissue handling
Meticulous control of hemorrhage
Observe strict aseptic technique
Preserve blood supply to tissues
Eliminate dead space
Appose tissues accurately w/ minimal tension
```
146
What are the seven wound factors for decision making/planning?
Size, geometric shape, anatomic location, chronicity, bacterial load, structural damage, peri-wound status
147
What species has lower cutaneous perfusion and early wound breaking strength?
Cats
148
What type of closure patterns are used for fascial/intramuscular closure?
Simple interrupted or continuous
149
What is the most common suture material?
Polydioxanone (PDS)
150
What is the minimum amount of throws to start continuous PDS?
5
151
What is the minimum amount of throws to finish continious PDS?
7
152
What size suture is used for SQ wound closure?
3-0 & 4-0
153
What suture pattern is used for SQ wound closure?
Simple continious
154
What does adding 2 extra throws do?
Increases knot volume & tissue reactivity by factor of 1.5
155
What are the typical subcuticular --> intradermal closure patterns?
Continuous horizontal, continuous vertical or SQ-to-intradermal
156
What are the typical suture material for cutaneous wounds?
Ethilon or polypropylene
157
What type of wound closure should be avoided in wounds with tension?
Tissue adhesives (cyanoacrylate)
158
What happens if a wound was closed by direct approximation of edges?
Tension will lead to ischemia from suture pressure
159
What is commonly seen on wound closures of the extremities?
Biological tourniquet effect
160
CT orients in what direction in relation to tension?
parallel
161
What is the best way to close wounds in relation to tension lines?
Should be closed parallel with the tension lines
162
How are incision lines made in relation to tension lines?
Parallel to tension lines
163
How should you close wounds on extremities in relation to tension lines?
Perpendicular with tension lines
164
What is undermining and the purpose of it?
Draws upon full elastic potential of skin in closure used to allow for tension relief
165
What are the two methods to undermine tissue?
Blunt technique- closed to open blades. Performed in loose areolar hypodermal tissues associated w/ truncal skin
Sharp technique- open to closed blades. Appropriate in extremities
166
What are the three tension relieving suture patterns?
Mattress sutures (vertical/horizontal)
Far far near near
Far near far near
167
WHy is the horizontal mattress not ideal?
Concerned of potential compromised blood supply
168
What is the purpose of the far-far and near-near aspects of the tension relieving suture pattern?
Far-far eliminates tension-placed 1 cm from edge
| Near-near apposes and placed 5 mm from wound edges
169
What is the purpose of the releasing incision?
Made near defect to allow skin apposition
170
What is the purpose of walking sutures?
used to advance skin towards center of wound
171
When is a V-Y plasty indicated?
Chronic defects surrounded by inelastic skin & closing wounds near structures that would be distorted by closure under tension
Ex: eye
172
Which direction should the point of the chevron be made in terms of the defect?
Point of the chevron should be made away from defect
173
What direction of the central arm of the z-plasty made in terms of the wound direction?
Perpendicular to long axis of the wound
174
When is m-plasty used?
When one end of incision would be compromised by orifice, foot pad or for reconstruction of cranial aspect of mastectomy
175
What is the mechanical creep?
Skin can extend its natural boundaries through phenomenon
176
What is stress relaxation?
Less fore required to maintain collagen fibers because collagen loses natural recoil
177
Where should the first suture be placed when closing fusiform shaped defects?
Across widest part of wound-continue dividing in half with subsequent sutures
178
When closing crescent shaped defects, which side should have sutures placed farther apart?
Longer side of the wound- closes in a T
179
What stitch should be used to close the center of triangle shaped defects?
half-buried horizontal mattress stitch
180
What kind of suture pulls dog ear down and away from wound?
Apex cutaneous suture
181
What are the three distinct plexuses that make up subdermal plexus?
SQ- deep plexus
Cutaneous- middle
Subpapillary- superficial
182
Ensure adequate ___ & ___ of surroudning skin with subdermal pelxus flap
Redundancy & vascularity
183
What is the ideal flap length of a subdermal pleuxs flap?
1.5X length of wound
184
What is an advancement flap?
Shifting skin w/out rotation
185
What is a roatational pivotal flap?
Pivotal flaps that have curvillinear configuration- designed immediately adjacent to defect & best used to close triangular defects
186
What is a transpostition pivotal flap?
pivotal flap w/ linear axis
| 3:1 rule= flap length:width
187
How is a interpolation pivotal flap different from the transposition flap?
Base is located at some distance from defect
188
What areas on the body are flaps commonly predisposed to. seromas and why?
Flaps from lateral flank & thorax
| Large amount of deadspace
189
What do axial pattern flaps rely on at the base of the flap?
cutaneous artery and vein
190
When are axial flaps most commonly used?
facilitate wound closure after tumor resection or trauma
191
What flap is most commonly used to repair caudal abdominal flank, inguinal, preputial, perineal, thigh and stifle defects?
Caudal superficial epigastric APF
192
What flap is good for sternal defects?
Cranial superficial epigastric APF
193
What flap is good for medial/lateral tibial defects?
Genicular APF
194
What is. the most common composite flap?
Myocutaneous
195
What composite flaps are commony used for forelimb defects?
Latissimus dorsi myocutaneous flap
196
What flap is used to repair prepubic tendon ruptures or femoral hernias?
Cranial & Caudal Sartorius MF
197
What are the four phases of graft incorporation?
1. Adherence
2. plasma imbibition
3. Inosculation
4. Vascular ingrowth
198
When does Phase I adherence occur in graft incorporation and what occurs in this phase??
0-72 hrs
| Contraction of fibrin strands pulling graft closer to bed
199
When does Phase II adherence occur in graft incorporation and what occurs in this phase?
72 hrs-10 days
| fibrin to fibroblasts, leukocytes, phagocytes --> fibrous adhesion (glue)
200
Describe the plasmatic imbibition stage of graft incoporation
0-72+ hrs
graft vessels dilate & pull fibrinogen free, serum like fluid & cells into graft via capillary action
nourishes wound prior to blood vessel development
201
When does inosculation stage occur in graft incorporation and what occurs in this phase?
48/72 h-6 days
| anastomosis of cut ends of graft vessels w/ recipient bed
202
When does vascular ingrowth stage occur in graft incorporation and what occurs in this phase?
48 h-6/8 days
| ingrowth of new vessels from bed into graft
203
What is vascular ingrowth controlled by?
Cytokines
204
How long until reinnervation occurs after graft implantation?
3 weeks
205
What is a common graft used that has multiple slits cut parallel in rows to allow the graft to expand in two directions and increase in size?
Full-thickness meshed skin graft
206
What does the meshing of the skin graft provide?
Drainage, flexibility, conformity & expansion
207
When would you use a full-thickness meshed skin graft?
Drainage from a wound w/ minor exudate
Cover large defects
Reconstruction of irregular shaped surfaces
208
What type of mesh graft is recommended for most grafting needs?
Non-expanded- full thickness mesh graft
