Wound Healing and Wound Management Flashcards Preview

Surgery I > Wound Healing and Wound Management > Flashcards

Flashcards in Wound Healing and Wound Management Deck (282):
1

First to differentiate diseased and infected wounds from non-infected wounds

Egyptians

2

Relates use of mixtures containing homey, lint and grease for treating wounds

Ebers's Papyrus

3

Describes at least 48 types of wounds

Edwin Smith Surgical Papyrus

4

Successful surgical case

Patient survives
Pathology is removed and/or corrected
Patient's wound heals

5

Employed 2 types of treatment (spiritual and physical method)

Sumerians

6

Dispelled the theory of spontaneous generation of germs

Louis Pasteur

7

Started soaking surgical instruments in phenol and spraying operating room

Joseph Lister

8

Classified wounds into acute or chronic

Greeks

10

Doctor of Roman gladiators

Galen of Pergamum

10

Emphasized the need of moist environment to ensure adequate healing

Galen of Pergamum

11

Production of antiseptic dressing - cotton gauze impregnated with iodoform

Robert Wood Johnson

12

Normal wound healing pattern

1. Hemostasis and inflammation
2. Proliferation
3. Maturation and remodelling

13

Phase which begins immediately and ends within a few days

Inflammatory phase

14

Hungarian obstetrician who noted the incidence of puerperal fever was much lower if medical students washed their hands following cadaver dissection and prior to attending childbirth

Ignaz Phillipp Semmelweis

15

Capillary regression leads to a less vascularized wound

Remodeling phase

16

Precedes inflammation and initiates inflammation with the ensuing release of chemotactic factors from the wound site

Hemostasis

17

Wounding leads to (3)

1. Division of blood vessel and direct exposure of ECM to platelets
2. Direct exposure of subendothelial collagen to platelets
3. Release of wound active sibstances through platelet alpha granules

18

Complex cellular and biochemical cascade that leads to restitution of integrity and function

Wound healing

20

Direct exposure of subendothelial collagen to platelets results to

Platelet aggregation, coagulation and activation of coagulation cascade

21

Deposition of the fibrin-fibrinogen matrix and collagen, resulting in formation of the wound matrix and an increase in wound strength

Proliferation phase

22

Serves as scaffolding for the migration into the wound of inflammatory cells

Fibrin clot

23

Peaks at 24 to 48 hiurs but most do not survive in >1 day

Polymorphonuclear neutrophils

24

Functions of inflammatory cells (2)

1. Sterilize the ound
2. Secrete growth factors

25

Primary role of PMNs

Phagocytosis of bacteria and tissue debris

26

Disruption of tissue integrity

Wounding

27

Wound active substances include (4)

PDGF
TGF-beta
Platelet-activating factor
Fibronectin
Serotonin

28

Achieve significant numbers in the wound by 48-96 hours post-injury

Macrophages

29

First to infiltrate wound site

Polymorphonuclear neutrophils

30

PMNs are stimulated by (7)

Inc. vascular permeability
Release of local prostaglandins
Complement factors
IL-1
TNF-alpha
TFG, platelet factor 4
Bacterial products

30

Release proteases that participate in matrix and ground substance degradation in the early phase of wound healing

PMNs

32

Macrophages contribute to microbial stasis through (3)

Oxygen radical synthesis
Nitric oxide synthesis
Regulation of cell proliferation, matrix matrix synthesis and angiogenesis

33

Most pivotal function of macrophages

Activation and recruitment of other cells

34

Major source of cytokines early during inflammation which may have a significant influence on subsequent angiogenesis and collagen synthesis

PMNs

35

Less numerous than macrophages

T-lymphocytes

36

Do not appear to play a role in collagen deposition or acquisition of mechanical wound strength

PMNs

37

Remain present until wound healing is complete

Macrophages

38

Macrophages regulate cell proliferation, matrix synthesis and angiogenesis by releasing (5)

TGF
VEGF
Insulin-like GF
Epithelial GF
Lactate

39

Depletion of most wound T lymphocytes lead to (2)

Decreased wound strength
Decreased collagen content

40

Exert a down-regulating effect on fibroblast collagen synthesis

T lymphocytes

41

T lymphocytes exert a down-regulating effect on fibroblast collagen synthesis by

Cell-associated interferon, TNF-alpha and IL-1

42

Macrophages activate and recruit other cells via (2)

Mediators such as cytokines and GFs
Directly by cell-cell interaction and ICAM

43

Peaks at 1 week post-injury

T-lymphocytes

44

Spans 4-12 days

Proliferative Phase

45

Last to infiltrate the healing wound

Fibroblast and endothelial cells

46

Strongest chemotactic factor for fibroblasts

PDGF

47

Selective depletion of the CD8+ suppressor subset of T lymphocytes leads to

Enhanced wound healing

48

Activation of fibroblasts

Cytokines and GFs released by wound healing

49

Potent regulator of collagen synthesis through a mechanism involving ADP-ribosylation

Lactate

50

Ridges transition from inflammatory to proliferative phase of healing

T-lymphocytes

51

Main function of fibroblasts

Matrix synthesis and remodelling

52

Re-establishment of tissue continuity

Proliferative Phase

52

Fibroblasts isolated from wound (3)

Synthesize more collagen than nonwound fibroblasts
Proliferate less
Carry out matrix contraction

53

Most abundant protein in the body

Collagen

54

Type of collagen which is the major component of ECM in skin

Type I

55

Migration, replication and new capillary tube formation are under the influence of (2)

Cytokines
Growth factors as TNF-a, TGF-b and VEGF

56

Collagen is secreted by

Fibroblasts

57

Release of protocollagen results in

Hydroxylation of proline to hydroxyproline and of lysine to hydroxylysine

58

Type of collagen normally present in skin, becomes more prominent and important during the repair process

Type III

60

Composition of collagen

Glycine (in every third position)
Proline
Proline/lysine (2nd position)

61

Contains nonhelical peptide domains at both ends

Procollagen

62

Cleaves the nonhelical registration peptides extracellularly

Procollagen peptidase

62

Comprise a large portion of the ground substance that makes up granulation tissue

Glycosaminoglycans

63

Prolyl hydroxylase requires (3)

Oxygen and iron as cofactors
Alpha ketoglutarate as cosubstrate
Ascorbic acid as an electron donor

64

Major glycosaminoglycans present in wounds

Dermatan and chondroitin sulfate

65

Nonhelical peptide domains at both ends of procollagen

Registration peptides

66

Entwined three alpha-helical chains and is a right-handed superhelical structure

Procollagen

67

Breaks down collagen during maturation and remodelling

Matrix metalloprotinases

68

Net wound collagen content is a result of a balance between

Collagenolysis and collagen synth sis

69

Comprise a large portion of the ground substance that makes up granulation tissue

Glycosaminoglycans

70

Glycosaminoglycans couple with protein to form

Proteoglycans

71

A class of metalloproteinases that require activation and is a result of collagenase activity

Collagenolysis

72

Major glycosaminoglycans present in wounds

Dermatan and chondroitin sulfate

73

Factors that affect both aspects of collagen remodeling

Inc. new collagen transcription
Dec. collagen breakdown
By stimulating synthesis of tissue inhibitors of metalloproteinase

74

Continues for months postinjury, resulting in a mature, avascular and acellular scar

Scar remodelling

75

Postulted as the major cell responsible for wound contraction

Myofibroblast

76

Begins during the fibroblastic phase and is characterized by reorganization of previously synthesized collagen

Maturation and remodelling

77

Glycosaminoglycans couple with protein to form

Proteoglycans

78

Characteristic pattern of deposition of matrix at wound site

1. Fibronectin and collagen type III constitute the early matrix scaffolding
2. Glycosaminoglycans and proteoglycans
3. Collagen type I is the final matrix

79

Ultimate determinant of wound strength d integrity

Balance of collagen deposition and degradation

80

Undetectable until day 6 and then is increasingly expressed for the next 15 days of wound healing

Alpha smooth smooth muscle actin

81

Components of collagen

Hydroxyproline and hydroxylysine

82

Characterized primarily by proliferation and migration of epithelial cells adjacent to the wound

Epithlialization

83

Step of wound healing impaired by steroids and other immunosuppressants, congenital or acquired immune-deficient states

Inflammation

84

Begins during the fibroblastic phase and is characterized by reorganization of previously synthesized collagen

Maturation and remodelling

85

T/F: mechanical strength of the scar achieves that of the uninjured tissue after scar remodelling

False

86

T/F: the presence of granulation tissue is reassuring evidence that the healing process is under way

True

87

Step in wound healing impaired by anticoagulants, antiplatelet agents, and coagulation factor deficiency

Coagulation

88

Epithelialization of surgical wounds closed primarily is usually complete by

24-48 hours

89

Synthesis and hydroxylation of hydroxyproline and hydroxylysine are dependent on

Fe, alpha ketoglutarate and ascorbate

90

For a wound to be considered clean

1. Wound created in a sterile and nontraumatic fashion, in an area that is free of preexisting inflammation
2. The respiratory, alimentary, genital, or urinary tract was not entered
3. All persons involved in the case maintained strict aseptic technique

91

Signs of inflammation

Pain, swelling, heat, erythema, loss of function

92

For a wound to be considered contaminated

1.There was gross spillage from GIT
2. Genitourinary and biliary tracts were entered in the presence of local infection
3. Major break in aseptic technique

93

Wounds that heal in a predictable manner and time frame

Acute wounds

94

Gives granulation tissue its characteristic beefy red appearance

Angiogenesis

95

Wounds that have proceeded through the repair process without producing an adequate anatomic and functional result

Chronic wounds

96

Integrity of basement membrane is restored to which type of collagen during epithelialization

Type IV

97

In primary intention, wound strength reaches its maximum at about how many months and how many % that of normal skin?

3 months
70-80%

98

Gives myofibroblast contractile ability

Alpha smooth muscle actin in thick bundles

99

Occurs after wound repair has ceased and can lead to undesirable effects

Scar contracture

100

Reasons for not using sutures

1. Wounds edges cannot be apposed because the defect is very large
2. Surgeon chooses not to close the wound primarily because of high risk of infection

101

For a wound to be considered clean-contaminated

Respiratory, alimentary, genital or urinary tract was entered, but there was no significant spillage of its contents and there was no established local infection; minor break in aseptic technique

102

Consisting of the placement of sutures, allowing the wound to stay open for a few days, and the subsequent closure of sutures

Third intention

103

Majority of wounds that have not healed in 3 months

Chronic wounds

104

Wound healing characterized by decreased wound-breaking strength compared to normal

Delayed healing

105

Incised wound that is clean and closed by sutures

Primary (first) intention

106

Wound healing characterized by a constant and continual increase that reaches a plateau at some point postinjury

Normal healing

107

Wound healing characterized by a failure to achieve mechanical strength equivalent to normally healed wounds

Impaired healing

108

T/F: Superficial injury of the cartilage is fast to heal.

False

109

T/F: delayed healing eventually achieve the same integrity and strength as wounds that heal normally

True

110

Type of healing seen following closure of wounds that are not approximated with sutures

Second intention

111

For a wound to be considered dirty/infected

1. The wound was the result of remote trauma and contains devitalized tissue and/or purulent material
2. There is established infection or perforated viscera prior to the procedure

112

3 crucial steps in healing

1. Survival of axonal bodies
2. Regeneration of axons that grow across transected nerve to reach the distal stump
3. Migration and connection of the regenerating nerve ends to the appropriate nerve ends or organ targets

113

Accumulation of blood at fracture site containing devitalized soft tissue, dead bone and necrotic marrow

Initial stage of hematoma formation

114

Distinguishing feature of fetal wound healing

Lack of scar formation

115

T/F: Hypovascular tendons tend to heal with less motion and more scar formation than tendons with better blood supply

True

116

Effect of vitamin a deficiency in wound healing

Impaired fibroplasias, collagen synthesis, cross-linking and epithelialization

117

Fibril formation and crosslinking results in

Dec. collagen solubility
Inc. strength
Inc. resistance to enzymatic degradation of collagen matrix

118

Effect of corticosteroids in wound healin

Reduce wound inflammation, collagen synthesis and contraction

119

Effect of diabetes mellitus in wound healing

Impair keratinocyte growth factor and platelet-derived growth factor functions in the wound

120

T/F: degree of nutritional impairment need not be long standing in humans to affect wound healing

True

121

Types of nerve injuries and definition

1. Neurapraxia - focal demyelination
2. Axonotmesis - interruption of axonal continuity but preservation of Schwann cell basal lamina
3. Neurotemesis - complete transection

122

T/F: supplemental vitamin a can reverse the inhibitory effects of corticosteroids on wound healing

True

123

Phagocytic removal of degenerating axons and myelin sheath from distal stump

Wallerian degeneration

124

Effects of zinc deficiency in wound healing

Dec. fibroblast proliferation, dec. collagen synthesis, impaired overall wound strength, delayed epithelialization

125

Breaks down collagen during maturation and remodelling

Matrix metalloprotinases

126

Net wound collagen content is a result of a balance between

Collagenolysis and collagen synth sis

127

T/F: Immediate use of steroids postop does not affect wound healing severely

False

128

Most common organisms responsible for wound infection (in order of frequency)

1. Staphylococcus species
2. Coagulase-negative streptococcus
3. Enterococci
4. Escherichia coli

129

Most well-known element in wound healing

Zinc

130

Definition of wound infection (3)

1. All wounds draining pus, whether or not the bacteriologic studies are positive
2. Wounds that are opened by the surgeon
3. Wounds that the surgeon considers infected

131

Basis of selection of antibiotics for use in prophylaxis (3)

1. Type of surgery to be performed
2. Operative contaminants that might be encountered during the procedure
3. The profile of resistant organisms present at the institution where the surgery is performed

132

Wound infection that involves skin and subcutaneous tissue only

Superficial incisional

133

Most dangerous of the deep infections

Necrotizing fasciitis

134

Differentiate contamination, colonization, infection

Contamination - presence of bacteria without multiplication
Colonization - multiplication without host response
Infection - presence of host response in reaction to deposition and multiplication of bacteria

135

Effect of vitamin c deficiency in wound healing

Inadequate collagen production

136

Organisms most commonly responsible for CGD (5)

S. Aureus
Aspergillus
Klebsiella
Serratia
Candida

137

Effect of vitamin b6 deficiency in wound healing

Impaired collagen cross-linking

138

Factors affecting the level of vasoconstriction of the subcutaneous capillary bed

Fluid status, temperature, hyperactive sympathetic tone

139

Major component of chronic wounds

Skin ulcers

140

Used to diagnose CGD

Nitroblue tetrazolium reduction test

141

T/F: mild to moderate normovolemic anemia does not appear to adversely affect wound oxygen tension and collagen synthesis unless the hematocrit falls below 10%

False (15%)

142

Wound infection that arise immediately adjacent to fascia, either above or below it, and may often have an intraabdominal component

Deep incisional

143

Ulcers that occur due to a lack of blood supply

Ischemic arterial ulcers

144

An ulcer that fails to re-epithelialize despite the presence of adequate granulation tissue

Venous stasis ulcer

145

Antibiotic prophylaxis is most effective when (2)

1. Adequate concentrations of antibiotic are present in the tissues at the time of incision
2. Adequate preoperative antibiotic dosing and timing

146

Ischemic arterial ulcers are usually present at

Most distal portions of the extremities such as the interdigital clefts

147

Most common site of stasis ulcer

Above the medial malleolus, over Cockett's perforator

148

Treatment of venous ulcers

Compression therapy

149

Type of wound healing used following removal of ruptured appendix in which there is leakage of pus into the peritoneal cavity

Third intention

150

Localized area of tissue necrosis that develops when soft tissue is compressed between a bony prominence and an external surface

Decubitus or pressure ulcers

151

Effect of oxygenation in wound healing

Augment collagen synthesis

152

Differentiate sensory neuropathy from motor neuropathy

Sensory - allows unrecognized injury to occur from ill-fitting shoes, foreign bodies, or other trauma
Motor (Charcot's foot) - leads to collapse or dislocation of the interphalangeal or metatarsophalangeal joints, causing pressure on areas with little protection

153

Ulcer which is a site of incompetent perforators

Stasis ulcers

154

Malignant wounds are differentiated clinically from nonmalignant wounds by

Presence of overturned wound edges

155

Infection of any anatomical structure remote from the incisional site but manipulated during the procedure

Organ/space surgical site infection

156

Dose of contaminating microorganisms required to result in an increased risk of wound infection

10^5

157

Type of healing seen following closure if wounds in which there is obvious gross contamination at the incisional site

Third (delayed primary) intention

158

Poor operative techniques that may lead to wound failure

Suture material with inadequate tensile strength
Inadequate. Umber of sutures
Too small bite size

159

Similarities of hypertrophic scars and keloids

Both occur after trauma to the skin and may be tender, pruritic and cause a burning sensation
Histologically - demonstrate increased thickness of the epidermis with absence of rete ridges, abundance of collagen and glycoprotein deposition

160

Major contributors of diabetic ulcers

Neuropathy (60-70%) secondary to persistently elevated glucose
Foot deformity
Ischemia (15-20%)

161

T/F: vitamin a have absolutely helps in normally healing wounds

False

162

Four stages of pressure ulcer formation

Stage I - nonblanching erythema of intact skin
Stage II - partial-thickness skin loss involving epidermis or dermis or both
Stage III - full-thickness skin loss, but not through the fascia
Stage IV - full-thickness skin loss with extensive involvement of muscle and bone

163

Removes pericellular transudate and wound exudate as well as deleterious enzymes

Negative pressure wound therapy

164

Absorption characteristics of dressings

None - films
Low - hydrogels
Moderate - hydrocolloids
Hig - foams, alginates, collagen

165

Genetically heterogeneous group of diseases in which the reduced NADPH-dependent oxide enzyme is deficient

Chronic granulomatous disease

166

Characteristic pattern of deposition of matrix at wound site

1. Fibronectin and collagen type III constitute the early matrix scaffolding
2. Glycosaminoglycans and proteoglycans
3. Collagen type I is the final matrix

167

T/F: negative pressure wound therapy cannot be used in ischemic, badly infected or inadequately debrided wounds or in malignancy

True

168

T/F: Wound dressing is contraindicated in infected and/or highly exudative wounds since it may enhance bacterial growth

True

169

Early surgical site infections that occur in the first 24 hours postop are most commonly due to

streptococcus or clostridium

170

Signs of infection to look for before administration of antibiotics

Erythema, cellulitis, swelling, purulent discharge

171

Differentiate dehiscence and incisional hernia

Dehiscence - if wound failure occurs early in the postop course before all stages of wound healing have occurred
Incisional hernia - if months or years postop

172

T/F: Occlusive and semiocclusive dressings are water-proof and impermeable to microbes, water vapor and oxygen

False

173

Guidelines for wound dressing

If nondraining - semi-occlusive dressing
If drainage (<1-2 ml/d) - semi-occlusive or absorbent nonadherent dressing
If moderately draining (3-5 ml/d) - nonadherent primary layer plus as absorbent secondary layer plus an occlusive dressing to protect normal tissue
If heavily draining (>5 ml/d) - same as above with the addition of a highly absorbent secondary layer

174

Tyoe of dressing designed to match the exudative properties of the wounds

Absorbent dressing

175

T/F: epinephrine can be used in wounds of the fingers, toes, ears, nose or penis due to risk of tissue necrosis secondary to terminal arteriole vasospasm

False

176

Basics of wound management

Optimize systemic parameters
Debride nonviable tissue
Reduce wound bioburden
Optimize blood flow
Reduce edema
Use dressings appropriately
Use pharmacologic therapy
Close wounds with grafts/flaps as indicated

177

Hypertrophic scars vs keloids

Hypertrophic scar - subside spontaneously, in areas under tension, formed along the incisional line

Keloids - spread beyond the margins of original wound and are painful, require treatment, around earlobes and the deltoid, presternal and upper back regions

178

Commonly painless ulcer which results from incompetence of the deep venous system

Chronic venous ulcer

179

Septic thrombosis of the vessels between the skin and the deep layers

Necrotizing fasciitis

180

Fibril formation and crosslinking results in

Dec. collagen solubility
Inc. strength
Inc. resistance to enzymatic degradation of collagen matrix

181

T/F: cancers arising de novo in chronic wounds include squamous cell carcinoma only

False (basal cell also)

182

Continues for months postinjury, resulting in a mature, avascular and acellular scar

Scar remodelling

183

T/F: mechanical strength of the scar achieves that of the uninjured tissue after scar remodelling

False

184

A class of metalloproteinases that require activation and is a result of collagenase activity

Collagenolysis

185

Factors that affect both aspects of collagen remodeling

Inc. new collagen transcription
Dec. collagen breakdown
By stimulating synthesis of tissue inhibitors of metalloproteinase

186

Ultimate determinant of wound strength d integrity

Balance of collagen deposition and degradation

187

Characterized primarily by proliferation and migration of epithelial cells adjacent to the wound

Epithlialization

188

Postulted as the major cell responsible for wound contraction

Myofibroblast

189

Gives myofibroblast contractile ability

Alpha smooth muscle actin in thick bundles

190

Undetectable until day 6 and then is increasingly expressed for the next 15 days of wound healing

Alpha smooth smooth muscle actin

191

Step in wound healing impaired by anticoagulants, antiplatelet agents, and coagulation factor deficiency

Coagulation

192

Signs of inflammation

Pain, swelling, heat, erythema, loss of function

193

Step of wound healing impaired by steroids and other immunosuppressants, congenital or acquired immune-deficient states

Inflammation

194

Components of collagen

Hydroxyproline and hydroxylysine

195

Synthesis and hydroxylation of hydroxyproline and hydroxylysine are dependent on

Fe, alpha ketoglutarate and ascorbate

196

Gives granulation tissue its characteristic beefy red appearance

Angiogenesis

197

T/F: the presence of granulation tissue is reassuring evidence that the healing process is under way

True

198

Integrity of basement membrane is restored to which type of collagen during epithelialization

Type IV

199

Epithelialization of surgical wounds closed primarily is usually complete by

24-48 hours

200

Occurs after wound repair has ceased and can lead to undesirable effects

Scar contracture

201

For a wound to be considered clean

1. Wound created in a sterile and nontraumatic fashion, in an area that is free of preexisting inflammation
2. The respiratory, alimentary, genital, or urinary tract was not entered
3. All persons involved in the case maintained strict aseptic technique

202

For a wound to be considered clean-contaminated

Respiratory, alimentary, genital or urinary tract was entered, but there was no significant spillage of its contents and there was no established local infection; minor break in aseptic technique

203

For a wound to be considered contaminated

1.There was gross spillage from GIT
2. Genitourinary and biliary tracts were entered in the presence of local infection
3. Major break in aseptic technique

204

For a wound to be considered dirty/infected

1. The wound was the result of remote trauma and contains devitalized tissue and/or purulent material
2. There is established infection or perforated viscera prior to the procedure

205

Wounds that heal in a predictable manner and time frame

Acute wounds

206

Majority of wounds that have not healed in 3 months

Chronic wounds

207

Wounds that have proceeded through the repair process without producing an adequate anatomic and functional result

Chronic wounds

208

Incised wound that is clean and closed by sutures

Primary (first) intention

209

In primary intention, wound strength reaches its maximum at about how many months and how many % that of normal skin?

3 months
70-80%

210

Type of healing seen following closure of wounds that are not approximated with sutures

Second intention

211

Reasons for not using sutures

1. Wounds edges cannot be apposed because the defect is very large
2. Surgeon chooses not to close the wound primarily because of high risk of infection

212

Type of healing seen following closure if wounds in which there is obvious gross contamination at the incisional site

Third (delayed primary) intention

213

Consisting of the placement of sutures, allowing the wound to stay open for a few days, and the subsequent closure of sutures

Third intention

214

Type of wound healing used following removal of ruptured appendix in which there is leakage of pus into the peritoneal cavity

Third intention

215

T/F: delayed healing eventually achieve the same integrity and strength as wounds that heal normally

True

216

Wound healing characterized by decreased wound-breaking strength compared to normal

Delayed healing

217

Wound healing characterized by a constant and continual increase that reaches a plateau at some point postinjury

Normal healing

218

Wound healing characterized by a failure to achieve mechanical strength equivalent to normally healed wounds

Impaired healing

219

Accumulation of blood at fracture site containing devitalized soft tissue, dead bone and necrotic marrow

Initial stage of hematoma formation

220

T/F: Superficial injury of the cartilage is fast to heal.

False

221

T/F: Hypovascular tendons tend to heal with less motion and more scar formation than tendons with better blood supply

True

222

Types of nerve injuries and definition

1. Neurapraxia - focal demyelination
2. Axonotmesis - interruption of axonal continuity but preservation of Schwann cell basal lamina
3. Neurotemesis - complete transection

223

3 crucial steps in healing

1. Survival of axonal bodies
2. Regeneration of axons that grow across transected nerve to reach the distal stump
3. Migration and connection of the regenerating nerve ends to the appropriate nerve ends or organ targets

224

Phagocytic removal of degenerating axons and myelin sheath from distal stump

Wallerian degeneration

225

Distinguishing feature of fetal wound healing

Lack of scar formation

226

Effect of vitamin c deficiency in wound healing

Inadequate collagen production

227

Effect of vitamin a deficiency in wound healing

Impaired fibroplasias, collagen synthesis, cross-linking and epithelialization

228

Effect of vitamin b6 deficiency in wound healing

Impaired collagen cross-linking

229

Effect of oxygenation in wound healing

Augment collagen synthesis

230

Effect of corticosteroids in wound healin

Reduce wound inflammation, collagen synthesis and contraction

231

Effect of diabetes mellitus in wound healing

Impair keratinocyte growth factor and platelet-derived growth factor functions in the wound

232

T/F: degree of nutritional impairment need not be long standing in humans to affect wound healing

True

233

T/F: supplemental vitamin a can reverse the inhibitory effects of corticosteroids on wound healing

True

234

Most well-known element in wound healing

Zinc

235

Effects of zinc deficiency in wound healing

Dec. fibroblast proliferation, dec. collagen synthesis, impaired overall wound strength, delayed epithelialization

236

T/F: Immediate use of steroids postop does not affect wound healing severely

False

237

Antibiotic prophylaxis is most effective when (2)

1. Adequate concentrations of antibiotic are present in the tissues at the time of incision
2. Adequate preoperative antibiotic dosing and timing

238

Basis of selection of antibiotics for use in prophylaxis (3)

1. Type of surgery to be performed
2. Operative contaminants that might be encountered during the procedure
3. The profile of resistant organisms present at the institution where the surgery is performed

239

Most common organisms responsible for wound infection (in order of frequency)

1. Staphylococcus species
2. Coagulase-negative streptococcus
3. Enterococci
4. Escherichia coli

240

Definition of wound infection (3)

1. All wounds draining pus, whether or not the bacteriologic studies are positive
2. Wounds that are opened by the surgeon
3. Wounds that the surgeon considers infected

241

Wound infection that involves skin and subcutaneous tissue only

Superficial incisional

242

Wound infection that arise immediately adjacent to fascia, either above or below it, and may often have an intraabdominal component

Deep incisional

243

Septic thrombosis of the vessels between the skin and the deep layers

Necrotizing fasciitis

244

Most dangerous of the deep infections

Necrotizing fasciitis

245

Differentiate contamination, colonization, infection

Contamination - presence of bacteria without multiplication
Colonization - multiplication without host response
Infection - presence of host response in reaction to deposition and multiplication of bacteria

246

Genetically heterogeneous group of diseases in which the reduced NADPH-dependent oxide enzyme is deficient

Chronic granulomatous disease

247

Used to diagnose CGD

Nitroblue tetrazolium reduction test

248

Organisms most commonly responsible for CGD (5)

S. Aureus
Aspergillus
Klebsiella
Serratia
Candida

249

Factors affecting the level of vasoconstriction of the subcutaneous capillary bed

Fluid status, temperature, hyperactive sympathetic tone

250

T/F: mild to moderate normovolemic anemia does not appear to adversely affect wound oxygen tension and collagen synthesis unless the hematocrit falls below 10%

False (15%)

251

Major component of chronic wounds

Skin ulcers

252

Malignant wounds are differentiated clinically from nonmalignant wounds by

Presence of overturned wound edges

253

T/F: cancers arising de novo in chronic wounds include squamous cell carcinoma only

False (basal cell also)

254

Ulcers that occur due to a lack of blood supply

Ischemic arterial ulcers

255

Ischemic arterial ulcers are usually present at

Most distal portions of the extremities such as the interdigital clefts

256

An ulcer that fails to re-epithelialize despite the presence of adequate granulation tissue

Venous stasis ulcer

257

Commonly painless ulcer which results from incompetence of the deep venous system

Chronic venous ulcer

258

Ulcer which is a site of incompetent perforators

Stasis ulcers

259

Most common site of stasis ulcer

Above the medial malleolus, over Cockett's perforator

260

Treatment of venous ulcers

Compression therapy

261

Major contributors of diabetic ulcers

Neuropathy (60-70%) secondary to persistently elevated glucose
Foot deformity
Ischemia (15-20%)

262

Differentiate sensory neuropathy from motor neuropathy

Sensory - allows unrecognized injury to occur from ill-fitting shoes, foreign bodies, or other trauma
Motor (Charcot's foot) - leads to collapse or dislocation of the interphalangeal or metatarsophalangeal joints, causing pressure on areas with little protection

263

Localized area of tissue necrosis that develops when soft tissue is compressed between a bony prominence and an external surface

Decubitus or pressure ulcers

264

Four stages of pressure ulcer formation

Stage I - nonblanching erythema of intact skin
Stage II - partial-thickness skin loss involving epidermis or dermis or both
Stage III - full-thickness skin loss, but not through the fascia
Stage IV - full-thickness skin loss with extensive involvement of muscle and bone

265

Early surgical site infections that occur in the first 24 hours postop are most commonly due to

streptococcus or clostridium

266

Infection of any anatomical structure remote from the incisional site but manipulated during the procedure

Organ/space surgical site infection

267

Dose of contaminating microorganisms required to result in an increased risk of wound infection

10^5

268

Poor operative techniques that may lead to wound failure

Suture material with inadequate tensile strength
Inadequate. Umber of sutures
Too small bite size

269

Differentiate dehiscence and incisional hernia

Dehiscence - if wound failure occurs early in the postop course before all stages of wound healing have occurred
Incisional hernia - if months or years postop

270

Hypertrophic scars vs keloids

Hypertrophic scar - subside spontaneously, in areas under tension, formed along the incisional line

Keloids - spread beyond the margins of original wound and are painful, require treatment, around earlobes and the deltoid, presternal and upper back regions

271

Similarities of hypertrophic scars and keloids

Both occur after trauma to the skin and may be tender, pruritic and cause a burning sensation
Histologically - demonstrate increased thickness of the epidermis with absence of rete ridges, abundance of collagen and glycoprotein deposition

272

Basics of wound management

Optimize systemic parameters
Debride nonviable tissue
Reduce wound bioburden
Optimize blood flow
Reduce edema
Use dressings appropriately
Use pharmacologic therapy
Close wounds with grafts/flaps as indicated

273

Removes pericellular transudate and wound exudate as well as deleterious enzymes

Negative pressure wound therapy

274

Absorption characteristics of dressings

None - films
Low - hydrogels
Moderate - hydrocolloids
Hig - foams, alginates, collagen

275

T/F: vitamin a have absolutely helps in normally healing wounds

False

276

T/F: negative pressure wound therapy cannot be used in ischemic, badly infected or inadequately debrided wounds or in malignancy

True

277

Guidelines for wound dressing

If nondraining - semi-occlusive dressing
If drainage (<1-2 ml/d) - semi-occlusive or absorbent nonadherent dressing
If moderately draining (3-5 ml/d) - nonadherent primary layer plus as absorbent secondary layer plus an occlusive dressing to protect normal tissue
If heavily draining (>5 ml/d) - same as above with the addition of a highly absorbent secondary layer

278

T/F: epinephrine can be used in wounds of the fingers, toes, ears, nose or penis due to risk of tissue necrosis secondary to terminal arteriole vasospasm

False

279

Signs of infection to look for before administration of antibiotics

Erythema, cellulitis, swelling, purulent discharge

280

T/F: Wound dressing is contraindicated in infected and/or highly exudative wounds since it may enhance bacterial growth

True

281

Tyoe of dressing designed to match the exudative properties of the wounds

Absorbent dressing

282

T/F: Occlusive and semiocclusive dressings are water-proof and impermeable to microbes, water vapor and oxygen

False