Lecture 8 - Advanced Suture and Knots Flashcards
1
Q
What are the properties of the skin?
A
tension, shear, and viscoelasticity
2
Q
What is tension determined by?
A
the pull of collagen and elastin in dermal and hypodermal tissues
3
Q
What is the shear skin property?
A
mobile areas of skin with forces on either wound edge opposing the other
4
Q
How does viscoelasticity occur?
A
adaptation to prolonged stress
5
Q
What are the tension relieving techniques?
A
undermining tissues, tension-relieving sutures, skin stretching, relaxing incisions
6
Q
How do you undermine tissue?
A
You use metzenbaums to dissect superficial to the muscle
7
Q
What does undermining take advantage of?
A
the skin’s elastic potential
8
Q
What type of dissection does undermining use?
A
blunt and sharp dissection
9
Q
When should you not use undermining?
A
when the patient has cancer
10
Q
What are some tension-relieving sutures?
A
interrupted vertical mattress, interrupted or continuous horizontal mattress, quilled/stented/bolster, far-near-near-far, far-far-near-near, cruciate, and walking sutures
11
Q
What tissues is the vertical mattress used for?
A
skin, gingiva, fascia, and tissues under tension
12
Q
What bites are used for the vertical mattress suture?
A
far-far, near-near
13
Q
Which bites in the vertical mattress suture should be deep?
A
the far bites
14
Q
How far from the incision should the near bites in the vertical mattress suture be?
A
2 mm
15
Q
If the vertical mattress is tight, what type of suture pattern is it?
A
everting
16
Q
When does the vertical mattress appose best?
A
when the near bites are close
17
Q
Is the vertical mattress or horizontal mattress stronger?
A
vertical
18
Q
In what type of tissue should you use the quilled/stented pattern?
A
skin under tension
19
Q
What is the quilled/stented suture a modified suture of?
A
the interrupted vertical mattress that loops over a stent
20
Q
What type of pattern is the quilled/stended suture coupled with?
A
an appositional pattern at the skin edge
21
Q
What is a potential complication associated with the quilled/stented suture pattern?
A
ischemia between sutures or under stents
22
Q
When should the quilled/stented suture pattern be removed?
A
earlier than the remaining sutures
23
Q
In what type of tissue should you use a far-near-near-far pattern?
A
skin and fascia under tension
24
Q
What is the far-near-near-far pattern a modification of?
A
a vertical mattress pattern
25
The far-near-near-far suture pattern avoids excess ______ at the wound edge.
tension
26
What is the thickness of the bites in the far-near-near-far suture?
full thickness
27
In what type of tissue should you use a far-far-near-near pattern?
skin and fascia under tension
28
What is the far-far-near-near pattern a modification of?
modified vertical mattress
29
The far-far-near-near suture avoids excess ____ at the wound edge?
tension
30
What is the thickness of the bites in the far-far-near-near pattern?
full thickness
31
What is the purpose of the walking suture?
move skin across a defect, eliminate dead space, and distribute tension
32
In the walking suture, the suture bite in ____ is closer to the center of the \_\_\_\_\_.
fascia; wound
33
What effect does the walking suture cause?
cosmesis
34
What is cosmesis?
dimpling
35
When don't you use the walking suture?
with flaps or grafts
36
What are some ways to facilitate skin stretching?
pretensioning sutures, posttensioning sutures, presuturing, acute intraoperative skin stretching, and chronic skin expansion
37
When do you do pretensioning sutures?
48-72 hours preop
38
Pretensioning sutures are continuous through ______ or _____ with lead _____ \_\_\_\_\_.
skin; intradermal; split shots
39
Pretensioning sutures are considered ____ \_\_\_\_ \_\_\_\_\_.
external skin stretchers
40
What is pretensioning suture for and what mechanism does it use?
stress relaxation, mechanical creep
41
How often are pretensioning sutures tightened?
every 8-24 hours based on your judgement
42
When are posttensioning sutures applied?
postop to minimize skin tension
43
Posttensioning sutures are considered ____ \_\_\_\_\_\_ \_\_\_\_\_.
external skin sutures
44
What can be used to aid in posttensioning sutures?
bolster bandages
45
What is presuturing?
when sutures are placed around an area of planned excisioinn
46
What type of suture pattern is used in presuturing?
lembert sutures through intact skin to plicate skin
47
How many days before surgery is presuturing done?
3 days
48
What is acute intraoperative skin stretching used for and what mechanism does it use?
stress relaxation and limited mechanical creep
49
What tools can be used for acute intraoperative skin stretching?
skin hooks, towel clamps, and stay sutures
50
Acute intraoperative skin stretching provides constant \_\_\_\_\_\_.
tension
51
How long preop do you want to do acute intraoperative skin stretching?
30-45 minutes
52
What is chronic skin expansion used for?
to produce a new epidermis
53
In what patients is chronic skin expansion used for?
used in patients that have excessive skin loss
54
What type of effect does chronic skin expansion have?
delayed effect, biological creep
55
What tools are used for chronic skin expansion?
inflatable or expandable silicone elastomer devices
56
How do you do chronic skin expansion?
implant surgically, expand 10-15% every 2-3 days
57
What are some types of relaxing incisions?
mesh expansion, simple relaxing incision, plasties
58
How is mesh expansion facilitated?
multiple relaxing incisions adjacent to the incision
59
How big are the incisions in mesh expansion?
1 cm in length
60
How far from the incision are mesh expansion incisions made?
1 cm from the edge
61
How far apart of are incisions for mesh expansion made?
staggered rows 1 cm apart
62
What is a potential risk associated with mesh expansion?
skin necrosis
63
What part of the body is mesh expansion useful for?
extremities
64
What is a single relaxing incision?
a bipedicle flap - an incision parallel to the long axis wound
65
How does a single relaxing incision heal?
it heals by second intention
66
What is V-Y plasty?
a chevron incision with point away from the wound that closes in a y
67
What is V-Y plasty useful for?
to advance skin to a defect or near orifice
68
What is a Z plasty used for?
cicatrix or closure nearby a wound
69
How is a Z-plasty performed?
the transposition of 2 triangular flaps from a central limb
70
For a wound, the central arm of the Z plasty perpendicular to the long axis wound should be ____ cm away.
\>3cm
71
What is an M plasty?
one or both ends of fusiform incision is under tension
72
When is an M plasty used?
orifice, pat, or bilateral mastectomy
73
How is an M plasty closed?
as a Y
74
What is a fingertrap suture pattern used for?
to secure -ostomy tubes and anchor them to the skin
75
How is the fingertrap suture structured?
repeated loops crossed around tubes
76
What is the fingertrap suture used to prevent?
accidental distraction or slippage
77
When does friction increase in the fingertrap suture?
if distract/pull tube
78
What type of pattern is the kessler locking loop suture?
superior apposition
79
What is the Kessler locking loop suture used for?
smaller tendons and flat tendons
80
What does the kessler locking loop suture maintain in tendons?
gliding function
81
How is the three-loop pulley suture oriented?
3 loops oriented 120 degrees to each other
82
What is the three-loop pulley suture resistant to?
gap formation
83
What is the three-loop pulley suture good for?
circular tendons and larger tendons
84
What is the Bunnell-meyer suture used for?
circular tendons
85
What is a potential risk of the Burnell-Mayer suture?
it may damage the tendons microcirculation
86
What type of pattern is the Krackow pattern?
a locking-loop pattern
87
What type of tendons is the krackow suture good for?
larger tendons and circular or flat tendons
88
What is a potential risk of the Krackow suture?
may damage tendon circulation
89
Where is the knot located in the Krackow suture?
it is within the tendon center
90
What is the weakest point of a suture?
the knot
91
What are the most reliable knots?
superimposing square knots
92
How many throws should be done with an interrupted pattern?
4
93
How many throws should be done with a continuous pattern?
6-8
94
What are some types of knots?
square, granny, slipped, surgeons, and simple
95
What is knot strength?
force required to cause a knot to slip
96
What is knot security?
related to the coefficient of friction of suture and knot strength
97
What factors affect knot security?
1. material coefficient and memory 2. length of the cut suture ends and # of throws 3. structural configuration of the knot 4. body fluids/wound
98
What affects the net tensile strength of the suture line?
initial tensile strength of the suture and knot security
99
What are the principles of knot tying?
1. use the simplest secure knot for the suture material and the situation 2. avoid friction between the strands as it may weaken the suture 3. use appropriate tension 4. approximate tissues don't strangulate tissues 5. pull the 2 strands in opposite directions with uniform rate and parallel tension 6.avoid damage to the suture material that remains with the patient 7. knots should be secure and flat
100
How are knots buried?
take bites deep to superficial and then superficial to deep; in SQ or intradermal sutures
101
How do you bury a continuous pattern end knot?
superficial to deep, deep to superficial, then superficial to deep
102
What is the aberdeen method?
a method to end a continuous suture pattern
103
What are the benefits of the aberdeen method?
increased strength, increased security, decreased number of throws, and decreased size
104
What are self-locking sutures?
sutures that contain a loop at the end
105
What are self-locking sutures designed for?
laparoscopic procedures and can be used for intradermal
106
What is hemostasis used for?
visability of the surgical field, decrease potential for infection, minimize blood loss, reduce hematoma and seroma formation, and decrease surgical times
107
What are some methods of hemostasis?
electrocautery, bipolar vessel sealing device, harmonic scalpel, stapler devices, hemoclips, ligation, pressure/tamponade, torniquet/clamps/bandages, hemostatic agents, hypotension/hypothermia/reduced perfusion
108
What hemostatic agents are used for topical vasoconstriction?
epinephrine/adrenaline/ephedrine
109
What hemostatic agents are used for antifibrinolytics?
serine protease inhibitors, lysine analogues
110
What hemostatic agents are used as sealants?
fibrin (tisseel, evicel, vitagel) and synthetic (coseal, and duraseal)
111
What are some mechanical hemostatic agents?
gelatin (gelfoam, surgifoam), bovine collagen (avitene, helistat, instat, sanostat), oxidized cellulose (surgicel), bone wax, and ostene
112
What are some active hemostatic agents?
thrombin (floseal, surgiflo) and alginate (kaltostat, sorbsan)
113
What is the goal of ligation?
vascular strangulation
114
Where does transfication occur in ligation?
distal to encircling
115
What techniques are used for ligation?
simple encircling, transfixation, advanced circumferential friction knots
116
What is the three clamp technique used for?
ligation of large vessels and vascular pedicles
117
How do you perform the three clamp technique?
1. 3 parallel forceps placed ~ 0.5cm from one another, transect between 2 most distal 2. release most proximal forceps partially while trying ligature in 'crush' 3. release completely as ligature is tightened
118
When is encircling used?
for ligation of vessels, and small vascular pedicles
119
What can be done with encircling do prevent loosening?
a surgeons knot
120
How is halsted transfixing performed?
a bite is taken around the vessel but not tied, the ends are passed around the opposite side of the vessel to create the knot
121
How is modified transfixing performed?
a bite is taken in the vessel with a simple knot performed on one side. The suture ends are passed around the opposite side for a surgeons throw, then completion of the knot
122
How is figure-of-eight transfixing performed?
the suture needle is passed in figure-of-eight pattern through the vascular pedicle two times, the two loops are tied with a single knot
123
When is double transfixing used?
for large dog spays
124
How is double transfixing performed?
it is a modified technique with the use of two simple encircling around either uterine artery
125
What is the Miller's knot used for?
large vessels and pedicles; friction
126
How is the Miller's knot performed?
place a secure half hitch around the pedicle, one suture end passed around and looped through a space preserved by your finger
127
What is the modified miller's used for?
large vessels and pedicles
128
How does the Modified Miller's work?
it is a clove-hitch that binds itself when tightened, the 2 loops are parallel
129
What is the constrictor knot used for?
large vessels and pedicles
130
How does the constrictor knot work?
it is a clove-hitch that binds itself when tightened, 2 loops cross, and suture end over first loop and under both
131
What is the strangle knot useful for?
large vessels and pedicles
132
What is the strangle knot a modification of?
the constrictor with suture end going under and between the cross
133
What are self-locking loops designed for?
laproscopic surgery
134
What is a surgitie self-locking loop?
a loop suture in a carrier, loop over vessel/pedicle, and tied with a slip knot
135
What is a ligatie self-locking loop?
an absorbable device that closes like a zipper
136
What suture pattern is shown here?
a vertical mattress
137
What suture pattern is shown here?
quilled/stented
138
What suture pattern is shown here?
quilled/stented
139
What suture pattern is shown here?
far-near-near-far
140
What suture pattern is shown here?
far-far-near-near
141
What suture patten is shown here?
walking suture
142
What suture pattern is shown here?
pretensioning sutures
143
What suture pattern is shown here?
posttensioning sutures
144
What technique is shown here?
presuturing
145
What technique is shown here?
acute intraoperative skin stretching
146
What technique is shown here?
mesh expansion
147
What technique is shown here?
single relaxing incision
148
What technique is shown here?
V-Y plasty
149
What technique is shown here?
Z plasty
150
What technique is shown here?
M plasty
151
What technique is shown here?
fingertrap
152
What suture is shown here?
Kessler locking loop
153
What suture is shown here?
three-loop pulley
154
What suture is shown here?
Bunnell-mayer
155
What suture is shown here?
Krackow
156
What technique is shown here?
halsted transfixing
157
What technique is shown here?
modified transfixing
158
What technique is shown here?
figure-of-eight transfixing
159
What technique is shown here?
double transfixing
160
What knot is shown here?
a Miller's knot
161
What knot is shown here?
a modified Miller's knot
162
What knot is shown here?
a constrictor knot
