Suturing materials and epidermal closure techniques Flashcards Preview

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Flashcards in Suturing materials and epidermal closure techniques Deck (154):
1

Buried sutures can be used to close dead space, redistribute tension, decrease dehiscence and increase wound eversion.

T

2

When undermining wound edges, skin hooks are the least traumatic means of stabilising and mobilising wound edges.

T

3

The configuration of a suture denotes its composition.

T

4

Advantages of suture braiding include lower propensity for infection.

F Increased propensity to retain microorganisms.

5

Advantages of suture braiding include increased tensile strength.

T

6

Advantages of suture braiding include decreased fraying of cut ends.

T

7

Newer innovations include suture coating with either antibacterial or antitumor qualities

T

8

Disadvantages of braided sutures include poorer handling and knot-tying properties.

F Improved

9

Disadvantages of braided sutures include more resistance when pulled through tissue.

T

10

Sutures coated with silicone, Teflon and wax decreases friction.

T

11

Capillarity denotes a suture’s ability to wick fluid from an immersed end to its dry end.

T

12

Braided sutures have decreased capillarity.

F Increased

13

Sutures with increased capillarity are more likely to harbor bacteria

T

14

Tensile strength refers to the weight necessary to break a suture divided by the cross-sectional area.

T

15

Larger sutures have decreased tensile strength.

F Increased

16

Synthetic sutures tend to have decreased tensile strength compared to sutures of natural materials.

F Increased

17

Tensile strength can be decreased by physical factors, such as wetness or increased age of sutures

T

18

Due to shearing forces between the strands, braided sutures have decrease tensile strength

T

19

The number/size ranks of sutures refer to their tensile strength – the greater the tensile strength, the fewer the zeros.

T Ie 2-0 suture has more strength than 6-0.

20

All sutures with the same tensile strength will have the same calibre.

F Eg. The calibre of a 5-0 nylon will be smaller than a 5-0 gut because nylon is stronger.

21

Knot strength refers to the security of a tied knot and is defined by the degree of slippage that occurs in a knot.

T

22

Sutures with a decreased coefficient of friction slide more easily and have a lower knot strength.

T

23

Memory is the ability of a suture to return to its original size and shape after being stretched.

F This is true for elasticity.

24

Elasticity denotes the ability of a suture to regain its former shape after bending.

F This is true for memory

25

Knots in sutures with increased memory (eg. polypropylene and nylon) have a greater tendency to untie themselves.

T Should  throw extra ties with these sutures.

26

Sutures with increased memory are less difficult to handle.

F More difficult

27

Elasticity is a desirable quality for a surface suture as it means the suture will stretch with the tissue and also recoil when the swelling subsides.

T

28

Plasticity refers to a suture’s ability to retain their deformed shape rather than return to their original shape when stretched.

T

29

Plasticity is advantageous in knot tying because deformation of the suture may lead to a more secure knot.

T

30

Sutures made of natural materials are less immunogenic than synthetic materials.

F More immunogenic.

31

Sutures with a multifilament configuration are more immunogenic than those with a monofilament configuration.

T

32

Non-absorbable sutures are more immunogenic than absorbable sutures.

F Less immunogenic. The immune response elicited by absorbables cause their dissolution.

33

Large diameter sutures are more immunogenic than small diameter sutures.

T

34

All sutures exhibit at least some inflammatory response when placed in tissue.

T

35

Sutures made of natural material are degraded by proteolysis in contrast to synthetic sutures which are degraded by hydrolysis

T

36

Non-absorbable sutures cause less tissue reaction because they induce a fibrous shell which coats the suture and decreases the host response.

T

37

True suture allergy does not occur.

F Rarely.

38

Absorbable sutures are defined as those that lose the majority of their tensile strength within 60 days after placement in living tissue.

T  non-absorbable sutures maintain their tensile strength for periods >60 days.

39

The presence of wound infection does not affect suture absorption.

F Increases suture absorption.

40

Suture placement location does not affect the rate of suture absorption.

F Mucosa absorbed faster.

41

Surgical gut is the only absorbable suture made of natural materials.

T

42

Surgical gut is a twisted multifilament suture composed mostly of collagen.

T

43

Fast absorbing gut is recommended for internal use

F

44

There are two varieties of gut sutures: plain and chromic.

F Three varieties. Also fast-absorbing.

45

Plain surgical gut loses much of its tensile strength in 3 weeks.

F 7-10 days.

46

Plain surgical gut is completely absorbed by 70 days.

T

47

Fast-absorbing gut is heat treated for more rapid deterioration.

T

48

Fast absorbing gut is used in facial wound closure, or the placement of skin grafts where rapid absorption of the suture is desirable

T

49

Nearly all of the tensile strength of a fast-absorbing gut suture is lost within 7 days, and complete absorption takes 21-42 days.

T

50

PDS II has lower tensile strength than fast-absorbing gut initially does

F Fast-absorbing gut –low initial tensile strength, PDSII high initial tensile strength, 50% at 4 weeks, 25% at 6 weeks

51

The initial tensile strength of Glycomer 631 (Biosyn) has not been studied

T Known at have 49% retained tensile strength at 3 weeks

52

Chromic gut has been treated with chromate salts which increases the rate of absorption in tissue.

F
Decreases rate of absorption

53

Chromic gut maintains its tensile strength for 10-21 days and is completely absorbed after approximately 90 days.

T

54

Chromic gut is best used to suture skin edges.

F Ligate vessels or suture mucosal wounds.

55

A history of chromate sensitivity does not preclude use of the chromic gut suture.

F
dont use if chromate sensitivity/allergy

56

Disadvantages to gut sutures include unpredictable absorption rates, low tensile strength, and increased tissue sensitivity.

T

57

Polyglycolic acid (Dexon) is a synthetic absorbable suture.

T

58

Polyglycolic acid is a non-braided suture.

F Braided multifilament suture.

59

Polyglycolic acid sutures can be coated with polycaprolate coating to reduce drag when pulled through tissues.

T

60

The polyglycolic acid suture retains 65% of tensile strength for 2 weeks after placement and 35% 3 weeks after implantation.

T

61

The polygycolic acid suture is completely resorbed between 30-60 days after placement.

F 60-90 days.

62

Advantages to using the polyglycolic acid suture include good handling and knot security and low tissue reactivity.

T

63

Polyglactin 910 (Vicryl) is a coated braided multifilament suture.

T

64

Polyglactin 910 consists of a copolymer made from 90% glycolide and 10% l-lactide.

T

65

Polyglactin 910 has similar handling properties to polyglycolic acid but has less tense strength.

F More tensile strength.

66

Polyglactin retains 75% of its tensile strength at 2 weeks and 50% at 3 weeks, and it is completely resorbed after 56-70 days.

T

67

Vicryl-rapide is a more rapidly dissolving form of polyglactin 910.

T

68

Vicryl-rapide loses 50% of its tensile strength at 5 days and essentially all tensile strength within 10-14 days.

T

69

Lactomer (Polysorb) is a coated braided multifilament suture made of copolymers of lactic and glycolic acids

T

70

Lactomer retains 80% of its tensile strength at 5 weeks and over 30% at 10 weeks. respectively.

F 2 and 3 weeks

71

Polydioxanone (PDS) if a multifilament synthetic absorbable suture.

F Monofilament.

72

Polydioxanone has increased tensile strength when compared to polyglactin 910 or polyglycolic acid.

F Decreased tensile strength.

73

Polydioxanone is more slowly resorbed and retains its strength for longer than polyglactin 910 or polyglycolic acid.

T

74

Polydioxanone retains 70% of its original tensile strength at 2 weeks, 50% at 4 weeks, and 25% at 6 weeks.

T

75

Complete absorption of polydiaxanone takes approximately 3 months.

F 6 months. Absorption is negligible until 3 months.

76

Polydiaxanone may be useful in wounds under high tension or wounds that require prolonged dermal support.

T

77

Polytrimethylene carbonate (Maxon) is a multifilament synthetic absorbable suture.

F Monofilament.

78

Polytrimethylene carbonate has lower initial tensile strength than polydiaxanone.

F Higher initial tensile strength.

79

Polytrimethylene carbonate retains 81% of initial tensile strength at 2 weeks, 59% at 4 weeks, and 30% at 6 weeks.

T

80

Polytrimethylene carbonate is absorbed more slowly than polydiaxanone.

F More quickly. Its absorption starts 60 days after implantation.

81

Polytrimethylene carbonate has worse knot strength and handling properties compared to polydiaxanone, polyglycolic acid and polyglactin 910.

F Better.

82

Poliglecaprone 25 (Monocryl) is a monofilament absorbable synthetic sutre with superior handling and tying properties due to its increased pliability.

T

83

The knot strength of poliglecaprone is superior to polydiaxanone, polyglycolic acid, polyglactin 910 and polytrimethylene carbonate sutures.

T

84

Poliglecaprone has lower initial tensile strength than PDS II or Maxon.

F Higher.

85

Poliglecaprone’s strength diminishes more quickly than the other monofilament synthetic sutures.

T

86

Poliglecaprone 25 retains 60% of its initial tensile strength at 7 days, 30% at 2 weeks, and loses all of its tensile strength by 3-4 weeks.

T

87

Dyes Maxon sutures retain their tensile strength and remain in tissue slightly longer than the clear sutures.

T

88

Absorption of both clear and dyed poliglecaprone sutures is essentially completed by 2-3 months.

F 3-4 months.

89

Fast absorbing gut is a multifilament, with poor knot strength, high tissue reactivity and loses its tensile strength in 3-7days

T

90

Surgical silk is a multifilament suture composed of braided fibres of protein harvested from the cocoon of the silkworm larva.

T

91

Surgical silk is not absorbed.

F Completely absorbed within 2 years.

92

Surgical silk loses almost all of its tensile strength 6 months after implantation

F 1 year

93

Silk suture is very soft. It should not be used on mucosa or intertriginous areas

F

94

Silk suture has superior handling and knot tying characteristics

T

95

Silk suture use is limited due to its tendency to cause tissue reactions

T

96

Silk is a monofilament

F Multifilament

97

Silk had low tensile strength

T

98

Silk has poor knot strength

F

99

Silk has low memory

T

100

Polypropylene (prolene) has excellent knot strength

F Poor

101

Polybutester (novafil) has excellent knot strength

F Good

102

Nylon sutures have high tensile strength and are absorbed at a rate of 15-20% per year if left in tissue.

T

103

Monofilamentous nylon has a high degree of memory, decreasing its pliability, handling and knot security.

T

104

Nylon sutures are unaffected by moisture.

F Made more pliable by moisture.

105

Polypropylene (Prolene) is a multifilament synthetic suture.

F Monofilament.

106

Polypropylene has a lower tensile strength than other synthetic non-absorbable suture.

T

107

Polypropylene has low tissue reactivity and an extremely low fiction coefficient.

T therefore decreased knot security.

108

Polypropylene will eventually be degraded if left in tissue.

F therefore good to reapproximate ear cartilage

109

Polypropylene has significant plasticity.

T

110

Polyester is a braided multifilamentous synthetic suture that is soft and pliable.

T

111

Polyester has a high tensile strength, which is only exceeded by metal sutures.

T

112

Polyester is generally uncoated.

F Coated with Teflon, silicone or polybutylate.

113

Polybutester (Novofil) is a monofilament suture composed of polyglycol terephthate and polybutylene terephthate.

T

114

Polybutester exhibits elasticity.

T

115

Polyhexafluoropropylene-VDF (Pronova) is a monofilament non-absorbable suture composed of a polymer blend of polyvinylidene fluoride and polyvinylidene fluoridecohexafluropropylene.

T

116

Pronova has a high coefficient of friction.

F Low.

117

Most suture needles are composed of stainless steel.

T

118

An ideal suture needle is malleable, strong and sharp.

T

119

Malleability refers to a needle’s resistance to breaking under a given degree of bending.

T

120

Reshaping a bent needle generally does not affect the needle’s strength or lead to breakage.

F

121

Sharp needles result in less tissue trauma and better cosmetic results.

T

122

Needles are often coated with silicone or other lubricants to improve the ease of needle penetration.

T

123

There are two parts to a suture needle – the shank and the point.

F Three parts – also the body.

124

The shank is the portion of the needle that attaches to the suture.

T

125

The point is the weakest part of the needle.

F The shank is weakest.

126

The point is the largest pat of the needle-suture unit, and hence it determines the size of the suture tract.

F This is true for the shank.

127

The point of the needle extends from the tip of the needle to the largest cross-section of the body.

T

128

The body is the middle portion of the needle between the shank and the point.

T

129

The body is the strongest portion of the needle and this part should therefore be grasped with the needle holder.

T

130

A conventional cutting needle has its primary cutting edge on the outside of the curve.

F Inside.

131

Reverse cutting needles have their primary cutting edge on the inside of the curve.

F Outside.

132

Reverse cutting needles result in less tissue tearing by the suture after tying.

T

133

Rounded needles cause less tissue tearing than conventional or reverse cutting needles.

T Use in delicate areas or in fascia.

134

Staple placement is 50% faster than suture placement.

F 80% faster.

135

Staples have an increased risk of tissue strangulation, reactivity and infection than sutures. .

F Decreased risk

136

Flaps that are stapled have a lower risk of partial necrosis compared to sutured flaps.

F Higher risk.

137

Tissue adhesives are made of cyanoacrylate compounds.

T

138

Histoacryl is octyl cyanoacrylate.

F Dermabond is.

139

Dermabond is N-butyl-2-cyanoacrylate.

F Histoacryl is.

140

Octyl cyanoacrylate has improved flexibility, less tissue toxicity, and at least three times the bonding strength of n-butyl-2-cyanoacrylate.

T

141

Octyl cyanoacrylate is used with application of a single layer.

F Triple layer.

142

Horizontal mattress sutures should not be used when suturing flaps because there is a greater theoretical risk of dermal strangulation.

T Also shouldn’t used in poorly vascularised wounds.

143

Locking horizontal mattress suture is helpful for wounds that need wound edge compression or haemostasis

T

144

Horizontal mattress stitches can be placed with half of the suture buried in the dermis

T

145

The half-buried horizontal mattress stitch is often used as a ‘tip stitch’ to secure the triangular tips of flaps.

T

146

Half buried horizontal mattress stitch uses non absorbable suture

T

147

A running epidermal stitch is stronger than an interrupted stitch

F

148

A running locked suture can facilitate haemostasis.

T

149

The running subcuticular stitch minimises epidermal puncture points, allowing sutures to be left in place longer.

T

150

A buried vertical mattress suture results in more wound eversion than a buried butterfly suture.

F

151

Suture tracks occur when sutures have been left in place too long, needles and suture calibre is too large, or if sutures are tied too tightly.

T

152

Purse string suture decreases the diameter of a wound

T

153

The purse string suture involves vertically orientated bites spaces 5-10mm apart placed continuously along the circumference

F Horizontally

154

Wounds partially closed using a purse string suture may be left to granulate or may be closed with an overlying skin graft

T