Suturing materials and epidermal closure techniques Flashcards Preview

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

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

A

T

2
Q

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

A

T

3
Q

The configuration of a suture denotes its composition.

A

T

4
Q

Advantages of suture braiding include lower propensity for infection.

A

F Increased propensity to retain microorganisms.

5
Q

Advantages of suture braiding include increased tensile strength.

A

T

6
Q

Advantages of suture braiding include decreased fraying of cut ends.

A

T

7
Q

Newer innovations include suture coating with either antibacterial or antitumor qualities

A

T

8
Q

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

A

F Improved

9
Q

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

A

T

10
Q

Sutures coated with silicone, Teflon and wax decreases friction.

A

T

11
Q

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

A

T

12
Q

Braided sutures have decreased capillarity.

A

F Increased

13
Q

Sutures with increased capillarity are more likely to harbor bacteria

A

T

14
Q

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

A

T

15
Q

Larger sutures have decreased tensile strength.

A

F Increased

16
Q

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

A

F Increased

17
Q

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

A

T

18
Q

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

A

T

19
Q

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

A

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

20
Q

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

A

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

21
Q

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

A

T

22
Q

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

A

T

23
Q

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

A

F This is true for elasticity.

24
Q

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

A

F This is true for memory

25
Q

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

A

T Should  throw extra ties with these sutures.

26
Q

Sutures with increased memory are less difficult to handle.

A

F More difficult

27
Q

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.

A

T

28
Q

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

A

T

29
Q

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

A

T

30
Q

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

A

F More immunogenic.

31
Q

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

A

T

32
Q

Non-absorbable sutures are more immunogenic than absorbable sutures.

A

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

33
Q

Large diameter sutures are more immunogenic than small diameter sutures.

A

T

34
Q

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

A

T

35
Q

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

A

T

36
Q

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

A

T

37
Q

True suture allergy does not occur.

A

F Rarely.

38
Q

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

A

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

39
Q

The presence of wound infection does not affect suture absorption.

A

F Increases suture absorption.

40
Q

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

A

F Mucosa absorbed faster.

41
Q

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

A

T

42
Q

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

A

T

43
Q

Fast absorbing gut is recommended for internal use

A

F

44
Q

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

A

F Three varieties. Also fast-absorbing.

45
Q

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

A

F 7-10 days.

46
Q

Plain surgical gut is completely absorbed by 70 days.

A

T

47
Q

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

A

T

48
Q

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

A

T

49
Q

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

A

T

50
Q

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

A

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

51
Q

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

A

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

52
Q

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

A

F

Decreases rate of absorption

53
Q

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

A

T

54
Q

Chromic gut is best used to suture skin edges.

A

F Ligate vessels or suture mucosal wounds.

55
Q

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

A

F

dont use if chromate sensitivity/allergy

56
Q

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

A

T

57
Q

Polyglycolic acid (Dexon) is a synthetic absorbable suture.

A

T

58
Q

Polyglycolic acid is a non-braided suture.

A

F Braided multifilament suture.

59
Q

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

A

T

60
Q

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

A

T

61
Q

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

A

F 60-90 days.

62
Q

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

A

T

63
Q

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

A

T

64
Q

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

A

T

65
Q

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

A

F More tensile strength.

66
Q

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

A

T

67
Q

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

A

T

68
Q

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

A

T

69
Q

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

A

T

70
Q

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

A

F 2 and 3 weeks

71
Q

Polydioxanone (PDS) if a multifilament synthetic absorbable suture.

A

F Monofilament.

72
Q

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

A

F Decreased tensile strength.

73
Q

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

A

T

74
Q

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

A

T

75
Q

Complete absorption of polydiaxanone takes approximately 3 months.

A

F 6 months. Absorption is negligible until 3 months.

76
Q

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

A

T

77
Q

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

A

F Monofilament.

78
Q

Polytrimethylene carbonate has lower initial tensile strength than polydiaxanone.

A

F Higher initial tensile strength.

79
Q

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

A

T

80
Q

Polytrimethylene carbonate is absorbed more slowly than polydiaxanone.

A

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

81
Q

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

A

F Better.

82
Q

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

A

T

83
Q

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

A

T

84
Q

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

A

F Higher.

85
Q

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

A

T

86
Q

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.

A

T

87
Q

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

A

T

88
Q

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

A

F 3-4 months.

89
Q

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

A

T

90
Q

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

A

T

91
Q

Surgical silk is not absorbed.

A

F Completely absorbed within 2 years.

92
Q

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

A

F 1 year

93
Q

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

A

F

94
Q

Silk suture has superior handling and knot tying characteristics

A

T

95
Q

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

A

T

96
Q

Silk is a monofilament

A

F Multifilament

97
Q

Silk had low tensile strength

A

T

98
Q

Silk has poor knot strength

A

F

99
Q

Silk has low memory

A

T

100
Q

Polypropylene (prolene) has excellent knot strength

A

F Poor

101
Q

Polybutester (novafil) has excellent knot strength

A

F Good

102
Q

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

A

T

103
Q

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

A

T

104
Q

Nylon sutures are unaffected by moisture.

A

F Made more pliable by moisture.

105
Q

Polypropylene (Prolene) is a multifilament synthetic suture.

A

F Monofilament.

106
Q

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

A

T

107
Q

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

A

T therefore decreased knot security.

108
Q

Polypropylene will eventually be degraded if left in tissue.

A

F therefore good to reapproximate ear cartilage

109
Q

Polypropylene has significant plasticity.

A

T

110
Q

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

A

T

111
Q

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

A

T

112
Q

Polyester is generally uncoated.

A

F Coated with Teflon, silicone or polybutylate.

113
Q

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

A

T

114
Q

Polybutester exhibits elasticity.

A

T

115
Q

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

A

T

116
Q

Pronova has a high coefficient of friction.

A

F Low.

117
Q

Most suture needles are composed of stainless steel.

A

T

118
Q

An ideal suture needle is malleable, strong and sharp.

A

T

119
Q

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

A

T

120
Q

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

A

F

121
Q

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

A

T

122
Q

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

A

T

123
Q

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

A

F Three parts – also the body.

124
Q

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

A

T

125
Q

The point is the weakest part of the needle.

A

F The shank is weakest.

126
Q

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

A

F This is true for the shank.

127
Q

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

A

T

128
Q

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

A

T

129
Q

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

A

T

130
Q

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

A

F Inside.

131
Q

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

A

F Outside.

132
Q

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

A

T

133
Q

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

A

T Use in delicate areas or in fascia.

134
Q

Staple placement is 50% faster than suture placement.

A

F 80% faster.

135
Q

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

A

F Decreased risk

136
Q

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

A

F Higher risk.

137
Q

Tissue adhesives are made of cyanoacrylate compounds.

A

T

138
Q

Histoacryl is octyl cyanoacrylate.

A

F Dermabond is.

139
Q

Dermabond is N-butyl-2-cyanoacrylate.

A

F Histoacryl is.

140
Q

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

A

T

141
Q

Octyl cyanoacrylate is used with application of a single layer.

A

F Triple layer.

142
Q

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

A

T Also shouldn’t used in poorly vascularised wounds.

143
Q

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

A

T

144
Q

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

A

T

145
Q

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

A

T

146
Q

Half buried horizontal mattress stitch uses non absorbable suture

A

T

147
Q

A running epidermal stitch is stronger than an interrupted stitch

A

F

148
Q

A running locked suture can facilitate haemostasis.

A

T

149
Q

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

A

T

150
Q

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

A

F

151
Q

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.

A

T

152
Q

Purse string suture decreases the diameter of a wound

A

T

153
Q

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

A

F Horizontally

154
Q

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

A

T

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