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Flashcards in 17 Deck (62)
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1

how are needles define

fraction of a circlecord length (bite width)needle lengthneedle diameterneedle radius

2

channel vs laser drilled swaged needles

channel: suture is crimped in a depression in the body of the needlelaser: suture is crimped in a hole drilled in the body of the needle (less drag, better grip with needle holders)

3

breaking strength of suture

the stress value on a stress-strain curve at which the suture acutely fails

4

capillarity of suture

degree to which absorbed fluid is transferred along the suture linemultifilament > monofilament

5

creep of suture

tendency of suture to slowly and permanently deform under constant stress

6

elasticity of suture

degree to which suture will deform with load applied and return to normal shape when load is removed

7

knot pull out strength of suture

load required to break a suture deformed by a knotknots generally decr suture strength by 10-40%

8

knot strength of suture

force necessary to cause a knot to slip

9

memory of suture

tendency for a suture to return to its original shape after deformation

10

plasticity of suture

degree to which a suture will deform without breaking and will maintain shape after removal of the deforming force

11

pliability of suture

the ease of handling and the ability to change shape of suture

12

stress relaxation of suture

the ability of suture to reduce stress under constant strain

13

suture pull out value

the weight required to full a suture loop from tissuedepends on type of tissue fat < muscle< skin < fascia

14

tensile strength of suture

measure of a sutures ability to resist deformation and breakage and the stress at which it deforms (yield strength) or rupture (breaking/ultimate strength) occurs

15

general characteristics of monofilament vs multifilament suture

monofilament =less pliable, more susceptible to catastrophic damage from crushing/nicking, lower tissue drag and is smoothermultifilament =greater strength & pliability, more tissue drag, greater capillarity and tendency for bacT colonization

16

T/FCatgut is monofilament

FALSECatgut is multifilament suture with TWISTED not braided filaments

17

newer types of sutures

polyblend suture (core polymer and braided exterior): extremely strong and resistant to failureSelf anchoring, barbed suture: surface barbs, decrease bulky knots, monofilament

18

water soluble vs insoluble suture coating in terms of knot security

water soluble coatings improve knot securitywater insoluble coatings reduce knot security

19

antibiotic coating for suture

+PLUStriclosan: inhibitor of bacT fatty acid synthesis

20

study of PDS PLUS with % percent of wound infections

PDS PLUS (polydiaxone w triclosan)11% wound infection PDS5% wound infection PDS PLUS

21

two major mechanisms of suture absorption

1. hydrolytic: synthetics2. enzymatic: Catgut (acid phosphatase, leucine amino peptidase)

22

PDS in sterile urine vs infected urine

PDS polydioxanonesterile urine: lost all strength 3 daysinfected urine: lost all strength 1 day (Proteus)

23

Dexon in sterile urine vs infected urine

Dexon polyglycolic acidsterile urine: lost 64% strength in 10 daysinfected urine: lost all strength 1 day (Proteus)

24

T/F rates of suture absorption are dramatically increased in infected urine

TRUE

25

what sutures degrade more rapidly in alkaline pH

moncryl (polyglecaparone 25)maxon (polyglyconate)biosyn (glycomer 631)

26

what suture loses tensile strength rapidly in acidic pH

PDS polydioxanonenylon (even thought considered non absorbable)

27

T/Fprestraining suture material to reduce suture memory will enhance suture degredation

true

28

catgut characteristics

natural twisted multifilament intestinal submucosa/serosaabsorbable (variable) via enzymaticweak, not uniformhigh tissue reactioncompletely absorbed in 2-3 weeks

29

do NOT use catgut in

harsh environments (GI, urinary surgery)areas requiring prolonged strength (>5days)important structures (body wall closure, fascial repair)

30

list rapidly absorbing suture

Polyglycolic acid (dexon)polyglactin 901 (vicryl)--braided multifilamentpolyglecaparone 25 (monocryl)polyglytone 6211 (caprosyn)