Lecture 6 - Suture Materials & Patterns

Dr. Thompson

1. Provides hemostasis

2. Supports healing tissue by apposing and supporting tissue layers

What are suture's important roles in wound repair? (2)

1. type of tissue

2. anticipated duration of healing

Tissues have different requirements for suture support, depending on what 2 things?

clot

A ligature placed on a vessel may only need to function for hours, until a _____ is formed

muscle; subcutaneous tissue; skin

Some tissues, such as _____, _____, and _____ need support for only a few days

fascia

_____ requires weeks of support

tendon

A _____ requires months of support

1. Infection

2. Obesity

3. Malnutrition

4. Neoplasia

5. Drugs (e.g., steroids)

6. Collagen disorders

7. Hypoproteinemia

8. Radiation Therapy

What are some things that can delay wound healing? (8)

tissue strength

Maintain apposition of tissue until wound's _____ returns

subjective

_____ preferences, such as familiarity with the material, price, and availability, need also be taken into consideration when choosing a suture material

1. Easy to handle

2. Reacts minimally in tissue

3. Inhibits bacterial growth

4. Holds securely when knotted

5. Resists shrinking in tissue

6. Absorbs with minimal reaction after the tissue has healed

7. Noncapillary

8. Nonallergenic

9. Noncarcinogenic

10. Nonferromagnetic

What are the characteristics off ideal suture? (10)

true

T/F - The ideal suture material does not exist

United States Pharmacopeia (USP)

The most commonly used standard for suture size is the _____

-Denotes dimensions from fine to coarse

-According to a numeric scale

-With 12-0 being the smallest and 7 the largest

12-0; 7

The United States Pharmacopeia (USP) suture sizes range from _____ being the smallest to _____ being the largest

smallest to largest

3-0 -> 2-0 -> 0

Is this going from the largest to smallest size or smallest to largest size?

"three ought"

How do you read this?

3-0

"ought"

How do you read this?

0

should

The smallest diameter suture that will adequately secure wounded tissue [should/should not] be used in order to...

-Minimize trauma as the suture is passed through the tissue

-Reduce the amount of foreign material left in the wound

true

T/F - There is no advantage to using a suture that is stronger than the tissue to be sutured

torsional stiffness; diameter

The flexibility of a suture is determined by its _____ and _____, which influence its handling and use

flexible

_____ sutures are indicated for ligating vessels or performing continuous suture patterns

cannot

Less flexible sutures (e.g., wire) [can/cannot] be used to ligate small bleeders

nylon; surgical gut

_____ and _____ are relatively stiff compared with silk suture

intermediate

Braided polyester sutures have _____ stiffness

surface

The _____ characteristics of a suture influence the ease with which it is pulled through tissue (i.e., the amount of friction or "drag" and the amount of trauma caused)

more

Rough sutures cause [more/less] injury than smooth sutures

smooth

_____ suture surfaces are particularly important in delicate tissues, such as the eye

smooth

Sutures with [smooth/rough] surfaces

-Require greater tension to ensure good apposition of tissues

-Have less knot security

more

Braided materials have [more/less] drag than monofilament sutures

capillarity

Braided materials are often coated to reduce _____ and provide a smooth surface

1. teflon

2. silicone

3. wax

4. paraffin wax

5. calcium stearate

What materials are used to coat sutures? (5)

capillarity

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

nonabsorbable

Neutrophils and macrophages are too large to enter the interstices of the fiber, so infection may persist, particularly in _____ sutures

true

T/F - Braided materials (e.g., polyglycolic acid, silk) have degrees of capillarity

noncapillary

Monofilament sutures are considered [capillary/noncapillary]

true

T/F - Coating reduces the capillarity of some sutures

should not

Capillary suture materials [should/should not] be used in contaminated or infected sites

knot tensile strength

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

the normal tissue through which they are being placed

Sutures should be as strong as _____

tissue

Tensile strength of the suture should not greatly exceed the tensile strength of the _____

relative knot security

The holding capacity of a suture expressed as a percentage of its tensile strength

knot-holding capacity

_____ of a suture material is the strength required to untie or break a defined knot by loading the part of the suture that forms the loop

tensile strength

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

structure

Suture materials may be classified according to their _____ - "monofilament" or "multifilament"

behavior in tissue

Suture materials may be classified according to their _____ - "absorbable" or "non-absorbable"

origin

Suture materials may be classified according to their _____ - "synthetic", "organic" or "metallic"

1. structure

2. behavior in tissue

3. origin

What are the 3 things suture material is classified by?

monofilament

_____ sutures are made of a single strand of material

less

Monofilament sutures have [more/less] tissue drag than multifilament sutures

interstices

Monofilament sutures do not have _____ that may harbor bacteria or fluid

weaken; breakage

Care should be used in handling monofilament suture because nicking or damaging the material with forceps or needle holders may _____ the suture and predispose it to _____

twisted or braided

Multifilament sutures consist of several strands of suture that are _____ together

multifilament

Generally, _____ sutures are more pliable and flexible

true

T/F - Multifilament sutures may be coated to reduce tissue drag and enhance handling characteristics

monofilament

The following are characteristics of [multifilament/monofilament] suture:

-Non-wicking

-More memory

-Does not handle as well

multifilament

The following are characteristics of [multifilament/monofilament] suture:

-Wicking

-Less memory

-Good handling

2

There are __#__ major mechanisms of absorption that result in the degradation of absorbable sutures

organic

Sutures of _____ origin are gradually digested by tissue enzymes and phagocytized

hydrolysis

Sutures manufactured from synthetic polymers are principally broken down by _____

nonabsorbable

[Absorbable/nonabsorbable] sutures are ultimately encapsulated or walled off by fibrous tissue

1. surgical gut

2. chromic gut

3. multifilament

What are the absorbable suture materials/characteristics? (3)

reviewed

Absorbable Suture Materials: Review

60 days

Absorbable suture materials lose most of their tensile strength within _____

phagocytized; hydrolyzed

Absorbable suture materials eventually disappear from the tissue implantation site because they have been _____ or _____

catgut (surgical gut)

-Most common non-synthetic absorbable suture material

-Made from the submucosa of sheep intestine or the serosa of bovine intestine

collagen

Catgut (surgical gut) is approximately 90% _____

phagocytosis

Catgut (surgical gut) is broken down by _____

inflammatory

Catgut (surgical gut) elicits a notable _____ reaction

rapidly

Plain surgical gut loses strength [slowly/rapidly] after tissue implantation

tanning

"_____" (cross-linking of collagen fibers) slows absorption

increased

[Increased/decreased] tanning generally implies prolonged strength and reduced tissue reaction

true

T/F - Surgical gut is available as plain, medium chromic, or chromic

infected; catabolic

Surgical gut is rapidly removed from _____ sites or areas where it is exposed to digestive enzymes and is quickly degraded in _____ patients

wet

Surgical gut knots may loosen when _____

hydrolysis

Synthetic absorbable suture are, generally, broken down by _____

true

T/F - Synthetic absorbable suture cause minimal tissue reaction

true

T/F - The time to loss of strength and to absorption of synthetic absorbable suture is fairly constant even in different tissue

does not

Infection or exposure to digestive enzymes [does/does not] significantly influence the rate of absorption of most synthetic absorbable sutures

alkaline; contaminated

Polyglactin 910 and polyglycolic acid are more rapidly hydrolyzed in _____ environments, but they are relatively stable in _____ wounds

infected urine

Polyglycolic acid, polyglactin 910, and poliglecaprone 25 may be rapidly degraded in _____

sterile; E. coli

Polydioxanone, polyglyconate, and glycomer 631 are acceptable for use in _____ bladders and those infected with _____

Proteus spp.

Any suture that is degraded via hydrolysis may be at risk for accelerated degradation when the bladder is infected with _____

7 days

All common monofilament absorbable sutures have been shown to degrade within _____ in P. mirabilis-inoculated urine

1. organic nonabsorbable materials

2. synthetic nonabsorbable materials

3. metallic sutures

What are the 3 nonabsorbable suture materials?

silk

_____ is the most common organic nonabsorbable suture

silkworm

Braided multifilament suture made by a special type of _____

true

T/F - Organic nonabsorbable suture is marketed as uncoated or coated

organic nonabsorbable

_____ suture has excellent handling characteristics and often used in cardiovascular procedures

vascular grafts

Silk does not maintain significant tensile strength after 6 months and is therefore contraindicated for use in _____

contaminated sites

Organic nonabsorbable suture should be avoided in _____

braided multifilament; monofilmanet

Synthetic nonabsorbable suture is marketed as _____ threads or _____ threads

synthetic nonabsorbable

_____ sutures are typically strong and induce minimal tissue reaction

-toxic substances are released during their degradation

-their use may result in abscess or tumor formation

Cable ties should never be implanted in the body. Why? (2)

stainless steel

_____ is the material most commonly used for metallic sutures

twisted

Metallic sutures are available as monofilament or multifilament _____ wire

true

T/F - Surgical steel is strong and inert with minimal tissue reaction

inflammatory

Metallic suture knot ends evoke an _____ reaction

cut tissue

Metallic sutures have the tendency to _____

migrate

Metallic sutures may fragment and _____

is

Stainless steel [is/is not] stable in contaminated wounds

1. judging knot security

2. judging tissue reaction to suture materials

What are metallic sutures standard for? (2)