Sutures and Stitches

Question 1

What is a suture?

Answer 1

Any strand of material used to ligate blood vessels or to approximate tissues

Question 2

How are sutures sized?

Answer 2

By diameter, stated as number of O’s.

The higher the number of O’s, the smaller the diameter.

Question 3

What are the 2 most basic suture types?

Answer 3

Absorbable and non-absorbable

Question 4

What is an absorbable suture?

Answer 4

Suture that is completely broken down by the body (dissolving suture)

Question 5

What is a non-absorbable suture?

Answer 5

Suture that is not broken down (permanent suture)

Question 6

What are catgut sutures made of?

Answer 6

Purified collagen fibers from the intestine of healthy cows or sheep

Question 7

What are the two types of gut sutures?

Answer 7

Plain and chromic

Question 8

What is the difference between plain and chromic gut?

Answer 8

Chromic gut is treated with chromium salts (chromium trioxide), which results in more collagen cross links, making the suture more resistant to breakdown by the body

Question 9

What is a Vicryl suture?

Answer 9

Absorbable, braided, multifilamentous copolymer of lactide and glycoside

Question 10

How long does Vicryl retain its strength?

Answer 10

60% at 2 weeks, 8% at 4 weeks

Question 11

Should you ever use purple-colored Vicryl for skin closure?

Answer 11

No, it may cause purple tattooing

Question 12

What is PDS?

Answer 12

Absorbable, monofilament polymer of polydioxanone (absorbable fishing line)

Question 13

How long does PDS maintain its tensile strength?

Answer 13

70-74% at 2 weeks, 50-58% at 4 weeks, 25-41% at 6 weeks

Question 14

How long does PDS take to complete absorption?

Answer 14

180 days

Question 15

What is a silk suture?

Answer 15

Non-absorbable, braided protein filaments spun by the silkworm larva.

Question 16

What is a Prolene suture?

Answer 16

Non-absorbable suture (used for vascular anastomoses, hernias, abdominal fascial closure)

Question 17

What is a nylon suture?

Answer 17

Non-absorbable fishing line

Question 18

What is a monocryl suture?

Answer 18

Absorbable monofilament

Question 19

What kind of suture should be used for the biliary tract or the urinary tract?

Answer 19

Absorbable (otherwise the suture will end up as a nidus for stone formation)

Question 20

What is the purpose of a suture closure?

Answer 20

To approximate divided tissues to enhance wound healing

Question 21

What are the 3 types of wound healing?

Answer 21

1. Primary closure (intention)
2. Secondary intention
3. Tertiary intention

Question 22

What is primary intention?

Answer 22

When the edges of a clean wound are closed in some manner immediately (e.g. suture, Steri-Strips, staples)

Question 23

What is secondary intention?

Answer 23

When a wound is allowed to remain open and heal by granulation, epithelialization, and contraction.
Used for dirty wounds, otherwise an abscess can form.

Question 24

What is tertiary intention?

Answer 24

When a wound is allowed to remain open for a time and then closed, allowing for debridement and other wound care to reduce bacterial counts prior to closure

Question 25

What is another term for tertiary intention?

Answer 25

Delayed primary closure (DPC)

Question 26

What is classic time to wait before closing an open abdominal wound by DPC?

Answer 26

5 days

Question 27

What rule is constantly told to medical students about wound closure?

Answer 27

Approximate, don’t strangulate:
If sutures are pulled too tight, then the tissue becomes ischemic because the blood supply is decreased possibly resulting in necrosis, infection, or scar.

Question 28

What is a taper-point needle?

Answer 28

Round body, leaves a round hole in tissue

Question 29

What is a taper-point needle used for?

Answer 29

Suturing of soft tissue other than skin (e.g. GI tract, muscle, nerve, peritoneum, fascia)

Question 30

What is a conventional cutting needle?

Answer 30

Triangular body with the sharp edge toward the inner circumference.
Leaves a triangular hole in tissue.

Question 31

What is a conventional cutting needle used for?

Answer 31

Suturing of skin

Question 32

What is a vertical mattress stitch?

Answer 32

Simple stitch is made, the needle is reversed, and a small bite is taken from each wound edge.
The knot ends up on one side of the wound.

Question 33

What is the vertical mattress stitch also known as?

Answer 33

Far-far, near-near stitch.

Oriented perpendicular to the wound.

Question 34

What is a vertical mattress stitch used for?

Answer 34

Difficult-to-approximate skin edges.

Everts tissue well.

Question 35

What is a horizontal mattress stitch?

Answer 35

Simple stitch is made, the needle is reversed, and the same size bite is taken again.
Oriented parallel to wound.

Question 36

What is a simple running (continuous) stitch?

Answer 36

Stitches made in succession without knotting each stitch

Question 37

What is a subcuticular stitch?

Answer 37

Stitch (usually running) placed just underneath the epidermis, can be either absorbable or non-absorbable (pull-out stitch if non-absorbable)

Question 38

What is a purse-string suture?

Answer 38

Stitch that encircles a tube perforating a hollow viscus (e.g. gastrostomy tube), allowing the hole to be drawn tight and thus preventing leakage

Question 39

What is a GI anastomosis device?

Answer 39

Stapling device that lays two rows of small staples in a hemostatic row and automatically cuts in between them

Question 40

What is a suture ligature?

Answer 40

Suture is anchored by passing it through the vessel on a needle before wrapping around and occluding the vessel.
Prevents slippage of knot.
Used on larger vessels.

Question 41

What is a retention suture?

Answer 41

Large suture that is full thickness through the entire abdominal wall except the peritoneum.
Used to buttress an abdominal wound at risk for dehiscence.

Question 42

What is a pop-off suture?

Answer 42

Suture that is not permanently swaged to the needle, allowing the surgeon to pop-off the needle from the suture without cutting the suture