What is a suture?
Any strand of material used to ligate blood vessels or to approximate tissues
How are sutures sized?
By diameter, stated as number of O's. The higher the number of O's, the smaller the diameter.
What are the 2 most basic suture types?
Absorbable and non-absorbable
What is an absorbable suture?
Suture that is completely broken down by the body (dissolving suture)
What is a non-absorbable suture?
Suture that is not broken down (permanent suture)
What are catgut sutures made of?
Purified collagen fibers from the intestine of healthy cows or sheep
What are the two types of gut sutures?
Plain and chromic
What is the difference between plain and chromic gut?
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
What is a Vicryl suture?
Absorbable, braided, multifilamentous copolymer of lactide and glycoside
How long does Vicryl retain its strength?
60% at 2 weeks, 8% at 4 weeks
Should you ever use purple-colored Vicryl for skin closure?
No, it may cause purple tattooing
What is PDS?
Absorbable, monofilament polymer of polydioxanone (absorbable fishing line)
How long does PDS maintain its tensile strength?
70-74% at 2 weeks, 50-58% at 4 weeks, 25-41% at 6 weeks
How long does PDS take to complete absorption?
What is a silk suture?
Non-absorbable, braided protein filaments spun by the silkworm larva.
What is a Prolene suture?
Non-absorbable suture (used for vascular anastomoses, hernias, abdominal fascial closure)
What is a nylon suture?
Non-absorbable fishing line
What is a monocryl suture?
What kind of suture should be used for the biliary tract or the urinary tract?
Absorbable (otherwise the suture will end up as a nidus for stone formation)
What is the purpose of a suture closure?
To approximate divided tissues to enhance wound healing
What are the 3 types of wound healing?
1. Primary closure (intention) 2. Secondary intention 3. Tertiary intention
What is primary intention?
When the edges of a clean wound are closed in some manner immediately (e.g. suture, Steri-Strips, staples)
What is secondary intention?
When a wound is allowed to remain open and heal by granulation, epithelialization, and contraction. Used for dirty wounds, otherwise an abscess can form.
What is tertiary intention?
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
What is another term for tertiary intention?
Delayed primary closure (DPC)
What is classic time to wait before closing an open abdominal wound by DPC?
What rule is constantly told to medical students about wound closure?
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.
What is a taper-point needle?
Round body, leaves a round hole in tissue
What is a taper-point needle used for?
Suturing of soft tissue other than skin (e.g. GI tract, muscle, nerve, peritoneum, fascia)
What is a conventional cutting needle?
Triangular body with the sharp edge toward the inner circumference. Leaves a triangular hole in tissue.
What is a conventional cutting needle used for?
Suturing of skin
What is a vertical mattress stitch?
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.
What is the vertical mattress stitch also known as?
Far-far, near-near stitch. Oriented perpendicular to the wound.
What is a vertical mattress stitch used for?
Difficult-to-approximate skin edges. Everts tissue well.
What is a horizontal mattress stitch?
Simple stitch is made, the needle is reversed, and the same size bite is taken again. Oriented parallel to wound.
What is a simple running (continuous) stitch?
Stitches made in succession without knotting each stitch
What is a subcuticular stitch?
Stitch (usually running) placed just underneath the epidermis, can be either absorbable or non-absorbable (pull-out stitch if non-absorbable)
What is a purse-string suture?
Stitch that encircles a tube perforating a hollow viscus (e.g. gastrostomy tube), allowing the hole to be drawn tight and thus preventing leakage
What is a GI anastomosis device?
Stapling device that lays two rows of small staples in a hemostatic row and automatically cuts in between them
What is a suture ligature?
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.
What is a retention suture?
Large suture that is full thickness through the entire abdominal wall except the peritoneum. Used to buttress an abdominal wound at risk for dehiscence.
What is a pop-off suture?
Suture that is not permanently swaged to the needle, allowing the surgeon to pop-off the needle from the suture without cutting the suture