Suture & Suture Selection (Part 1)

Suture

any strand of material used to approximate the tissue edges and give artificial support while tissue heals naturally

hemostasis & support for healing tissue

Suture plays an important role in WOUND REPAIR by providing ____ & ____.

-type of tissue

-anticipated duration of healing

Requirements for suture support of tissues (2)

(1) muscle, subcutaneous tissue, skin

(2) fascia

(3) tendon

tissues that need support for only a (1) few days (2) weeks (3) months to heal

-infection

-obesity

-malnutrition

-neoplasia

-drugs

-collagen disorders

healing of wounds may be delayed by (6)

suture choice

individual PATIENT VARIATION further affects —-

T

T/F: MINIMALLY INVASIVE surgical techniques put addition demands on the performance of surgical sutures

surface lubricant

Not only must good knot security be maintaines but also the ______ must ensure *ease* *of manipulation*, *minimal tissue drag*, and *good biocompatibility with minimal inflammatory response*

familiarity and availability

subjective preferences, such as (2) need also be taken into consideration when choosing a sture material

-easy to handle

-reacts minimally in tissue

-inhibits bacterial growth

-holds securely when knotted

-resists shrinking in tissue

-absorbs wth minimal reaction

-non capillary

-non allergenic

-non carcinogenic

-non ferromagnetic

(however such a material does not exist)

the ideal suture is —- give at least 4

smallest diameter (that will adequately secure wounded tissue)

size of suture that should be used to *minimize trauma* as the suture is passed through the tissue and to *reduce the amount of foreign material left in the wound*

smallest: 12-0

largest: 7

smallest and largest size of suture

smaller; less

The ____ the suture size, the ____ tensile strength is has

fexibility

____ is determined by its *torsional stiffness and diameter* which influence its handling and use

-ligating vessels

-performing continuous suture patterns

*Flexible sutures* are indicated for

small bleeders

*less flexible sutures* CANNOT be used to ligate ____

nylon and surgical gut

These 2 types of suture are relatively *stiff* compared with silk suture

Braided polyester

_____ sutures have *intermediate stiffness*

surface characteristics and coating

They influence the ease with which it is pulled through tissue (amount of friction or drag) and the amount of trauma caused

T

T/F: rough surfaces cause more injury than smooth sutures

eye

smooth surfaces are particulary important in delicate tissues, such as the ___

greater tension

sutures with smooth surfaces also require _____ tension to ensure good appoistion of tissues and have less knt security

monofilament

*Braided* materials have more drag than _____ sutures

braided

___ materials are often *coated* to reduce capillarity, but this also provides a smooth surface

-monofilament

-multifilament

2 classification of suture materials accdg to structure

-smooth surface

-less tissue. trauma

-no bacterial harbors

-no capillarity

advantages of *monofilament*

-strength

-soft and pliable

-good handling

-good knotting

advantages of *multifilament*

-hhandling and knotting

-stretch

-any nick or crimp in the material leads to breakage

disadvantages of *monofilament*

-bacteria harbors

-capillary action

-tissue trauma

disadvantages of *multifilament*

capillarity

the process by which fluid and bacteria are carried into the interstices of multifilament fibers

infection; non absorbable

because neutrophils and macrophages are too large to enter the interstices of the fiber, ____ persists, particularly in ____ sutures.

coating

____ reduces the capillarity of some sutures

knot tensil strength

it is measured by the force in pounds that tha suture strand can withstand before it breaks when knotted

suture; tissue

the tensile strength of the ____ should not greatly exceed the tensile strength of the ___

F *(it should be as strong as the normal)*

T/F. sutures should be as stronger than the normal tissue through which they are being placed

relative knot security

It is the holding capacity of a suture expressed as a percentage of its tensile strength

Suture material's *tensile strength*

It is the *strength required to break an untied fiber* with a force applied in the direction of its length

*Knot-holding capacity* of a suture material

The *strength required to untie or break a defined knot* by loading the part of the suture that forms the loop.

Absorbability

*Progressive loss of mass and/or volume* of suture material. Does not correlate with initial tensile strength

breaking strength

*Limit of tensile strength* at which suture failure occurs

Capillarity

Extent to which *absorbed fluid is transferred along the suture*

Elasticity

Measure of the ability of the material to *regain its original form and length after deformation*

Fluid absorption

Ability to take up fluid after immersion

Knot-pull tensile strength

Breaking strength of knotted suture material

Knot strength

Amount of force necessary to cause a knot to slip

Memory

Inherent capability of suture to return to or maintain its original gross shape

Plasticty

Measure of the *ability to deform w/out breaking* and to maintain a new form after relief of the deforming force

Pliability

Ease of handling of suture material; ability to adjust knot tension and to secure knots

Straight-pull tensile strength

Linear breaking strength of suture material

Suture pullout value

The application of force to a loop of suture located where tissue failure occurs

tensile strength

Measure of the ability of a material or tissue to *resist deformation and breakage*

Wound breaking strength

Limit of tensile strength of a healing wound at which separation of the wound edges occurs

-Absorbable

-non absorbable

Specific suturing materials may be classified according to their *behavior in tissue.* Give the two.

-monofilament

-multifilament

classification of suture materials based on *structure*

-synthetic

-organic

-metallic

classification of suture materials based on *origin*

Absorbable suture

This suture is designed to break down over a specific time frame and be absorbed by the body

F (temporary only)

T/F. Absorbable sutures are used when *permanent*support is required

-Organic: phagocytosis & proteolysis

-Synthetis: hydrolysis

Absorption of absorbable sutures occurs by (2)

Natural sutures

____ are made from animal or plant materials. Their protein composition can elicit the most pronounced tissue reaction

Catgut (surgical gut)

It is the most common non synthetic absorbable suture material

Surgical gut

It is made from the *submucosa of sheep intestine or the serosa of bovine intestine*, approx 90% collagen

Inflammatory

Surgical gut is broken down by *phagocytosis* and elicits a notable _____ reaction

Increased

Catgut is available as plain, medium chromic, chromic; (increased/decreased?) tanning generally implies *prolonged strength and reduced tissue reaction*

T

T/F: surgical gut is rapidly removed from infected sites or areas where it is exposed to *digestive enzymes*, and is *quickly degraded in catabolic patients.* The knots may *loosen when wet*

Synthetic suture

___ materials cause *less tissue reaction* than natural fibers, therefore their *strength and absorption rate* is *more uniform and predictable* in all individuals.

Constant

The time to loss of strength and to absorption is fairly ____ in different tissue

T

T/F: infection or exposure to digestive enzymes *does not significantly influence the rate of absorption* of *most synthetic absorbable sutures*

-Polyglactin 910

-Polyglycolic acid

(2) are more rapidly hydrolyzed in *alkaline environments* but are relatively *stable in contaminated wounds*

Infected urine

*polyglactin 910, polyglycolic acid, and poliglecaprone 25* may be rapidly degraded in ___

-Polydioxanone

-polyglyconate

-glycomer 631

These synthetic sutures are acceptable for use in *sterile bladders* and those *infected with E. Coli*

hydrolysis

Use of any suture that is degraded via _____ may be at risk for accelerated degradation wen the bladder is infected with Proteus spp.

-Polydioxanone (PDS II)

-Polyglyconate (Maxon)

(2) are *classic monofilament sutures* that retain their tensile strength longer than multifilament sutures, with complete absorption occurring in 6 months

-Poliglecaprone 25 (Monocryl)

-Glycomer 631 (Biosyn)

(2) are *monofilament rapidly absorbable synthetic materials* that are pliable, lack stiffness, and have good handling characterictics

Initial tensile strength

Poliglecaprone 25 (Monocryl) and Glycomer 631 (Biosyn) have good _____ that deteriorates in 2-3 weeks following implantation, and are *completely absorbed by 120 days*

Polyglytone 6211 (Caprosyn)

This is *relatively new, rapidly absorbable monofilament suture*. It is a synthetic *polyester of glycolide, caprolactone, trimethylene carbonate, and lactide*

56

Absorption of Polyglytone 6211 (Caprosyn) is complete in ___ days, which is thought to lead to *less wound complications and tissure reactions*

Polyglytone 6211 (Caprosyn)

This suture retains up to *30% knot strength* at 10 days post implantation and has *excellent handling characteristics*

Polyglycolic acid (Dexon)

It is braided from filaments extracted from *glycolic acid*. Available in both coated and uncoated forms

Polyglactin 910 (Vicryl)

It is *multifilament suture coated with calcium sterate*, its rate of loss of tensile stength is similar to that of polyglycolic acid

Vicryl Rapide

It is a rapidly absorbed, synthetic braided suture that has an *initial strength that is comparable to nylon gut*. Completely absorbed in 42 days

Vicryl Rapide

This suture is indicated for *superficial closure of mucosa, gingival closure, and periocular skin closure*

Non-absorbable suture

This suture type is designed to either be left permanently in the body or are to be removed after a certain healing period

10-14

When non absorbable sutures are used to *close skin*, they are usually removed in ____ days.

Silk

It is the *most common organic non-absorbable suture material used*. Braided multifilament made by a special type of *silkworm*

Cardiovascular

Silk is often used in ___ procedures. SHould be avoided in contaminated sites

-polyester

-coated caprolactam

examples of *braided multifilament threads* (synthetic non-absorbable)

-polypropylene

-polyamide

-polybutester

examples of *monofilament threads* (synthetic non-absorbable)

infection and fistulation

non-absorbable suture materials with an *inner core and outer sheath* (ex. Supramid) *should not be buried in tissue* because it may predispose to —— (2)

Braided (Multifilament)

this construction involves *several filaments or strands* being braided or twisted together.

less

multifilament sutures pass (more/less) easily through tissue than smooth monofilaments and the resulting *tissue drag* can cause traua

they coated it

what was done by the manufacturers to reduce *tissue drag* of braided multifilament sutures?

monofilament

this type of suture construction results in *single strand or filament*

Monofilament

its surface is very smooth and passes easily through tissue. However, they can be *difficult to handle and tie* as they are *less flexible* than braided sutures

memory

most monofilaments have ___ that makes it more difficult to work with