Surgery & Suture Material

Question 1

what are halsted’s 7 principles of surgery

Answer 1

1. gentle tissue handling
2. aseptic technique during prep and surgery
3. preservation of blood supply
4. careful hemostasis
5. eliminate dead space
6. avoid tension
7. accurate tissue apposition

Question 2

what are additional surgical principles to adhere to

Answer 2

1. use appropriate instruments/materials
2. keep tissues moist
3. use appropriate incision length
4. appropriate duration of procedure
5. appropriate case management

Question 3

too small vs too large incision

Answer 3

too small: increased tension, trauma, and risk of injury

too large: increased risk of disrupting blood supply and longer closing time

Question 4

where should you grasp the needle with needle drivers

Answer 4

2/3 to 3/4 along the curve of the needle from the tip

Question 5

swaged on needles

Answer 5

needle attaches directly to the suture

recommended due to less tissue drag

Question 6

taper point needle

Answer 6

fine point with a rounded/circular cross section

used in delicate or luminal tissues

Question 7

cutting needle

Answer 7

triangular shaped cross section

used in tougher tissue with higher collagen (skin, fascia, etc)

Question 8

standard vs reverse cutting needle

Answer 8

standard: flat part of triangle is on the bottom

reverse: flat part of the triangle is on the top

Question 9

polydioxanone (PDS) characteristics

Answer 9

absorbable - LONG
synthetic
monofilament

used for fascia

Question 10

polyglecaprone 25 (monocryl) characteristics

Answer 10

absorbable - SHORT
synthetic
monofilament

strong initial tensile strength

Question 11

polyglycolic acid (vicryl) characteristics

Answer 11

absorbable - long and short
synthetic
multifilament

Question 12

chromic gut characteristics

Answer 12

absorbable - SHORT
biologic
monofilament

Question 13

nylon characteristics

Answer 13

non-absorbable
synthetic
monofilament

Question 14

silk characteristics

Answer 14

non-absorbable
biologic
multifilament

Question 15

polypropylene (prolene)

Answer 15

non-absorbable
synthetic
monofilament

Question 16

what are the 5 considerations for suture choice

Answer 16

1. rate of tensile strength loss
2. knot security
3. tissue reactivity
4. handling characteristics
5. initial suture strength

Question 17

what is the guideline for choosing a suture based off of rate of tensile strength loss

Answer 17

want the suture to maintain tensile strength long enough until the tissue is able to regain its own strength

rate differs by type of tissue

Question 18

critical healing period

Answer 18

period during which the wound is completely dependent on suture for holding strength

want suture tensile strength to be > clinically relevant tissue strength until tissue regains that amount of its original strength

Question 19

what can affect rate of healing/tissue regaining strength

Answer 19

comorbidities

Question 20

what is the primary holding layer for body wall closure

Answer 20

fascia

has the strength to be self supporting at 4 weeks post-op

Question 21

continuous suture pattern

Answer 21

greater tensile strength

entire line depends on 2 knots - if you lose one, you lose entire line

Question 22

interrupted suture pattern

Answer 22

slightly less strong compared to continuous

less risk of entire line failure

Question 23

Jenkins rule for fascial closure

Answer 23

minimum bite width of 1 cm from edge of fascial incision
(modified to 5-10 mm in animals)

each bite should be <1 cm away from the previous bite along the length of the incision

Question 24

what two suture characteristics contribute to decreased risk of incisional hernia

Answer 24

non absorbable sutures
long lasting absorbable sutures

ex. PDS and prolene

Question 25

what does knot security depend on

Answer 25

type and size of suture
knotting pattern
technical skill

Question 26

how many knots should be thrown in interrupted and continuous sutures

Answer 26

interrupted: 4 minimum
continuous: 5 minimum
- start: 5
- end: 6-7

Question 27

how does intrinsic friction affect knot security

Answer 27

greater friction = less likely to unravel = greater security

Question 28

how does coating affect knot security

Answer 28

coating = decreased intrinsic friction = decreased security

Question 29

how does stiffness affect knot security

Answer 29

greater stiffness (monofilament) = low knot security

less stiffness (multifilament) = high knot security

Question 30

what is the size scale for suture diameter

Answer 30

smallest: 11-0
moderate: 0
largest: 7

Question 31

does monofilament or multifilament cause more tissue reactivity

Answer 31

multifilament - silk, polyester

Question 32

what increases the likelihood of a suture site infection

Answer 32

amount of suture material

increased amount = less bacteria required to get an SSI

use monofilament when possible

Question 33

effects of too much/too little suture tension

Answer 33

too tight: reduced blood supply –> edema, necrosis, crushing injury

too loose: incision gap, delayed healing, risk of infection

Question 34

does monofilament or multifilament have greater suture memory

Answer 34

monofilament