Hi everyone,
For today's POTD, I want to review the suture choices we have available when performing laceration repairs in the ED. Much of our training for laceration repairs is on-the-job, informal practice and learning, but I want to offer a more systematic approach.
So, when you're getting all your equipment together for your laceration repair, what suture are you grabbing? And why? And whose "gut" are plain gut and chromic gut sutures coming from? We will go over questions to consider when making your choice, your suture options (with particular focus on what we have stocked at MMC), and some clinical examples for when you might choose each.
3 Questions to Consider When Choosing Your Suture
1) Tensile strength: How much tension is across the wound? A primary purpose of laceration repairs is to decrease tension across the wound. Remember everting edges? That's all in an attempt to give the wound a little extra skin to work with in case the tension does pull the edges apart as it heals. Whether to evert or not is controversial these days (definitely don't invert, though). But when it comes to sutures, the primary principle remains: choose the smallest size suture that can best fight the tension you're up against.
2) Site of laceration: Where on the body are you repairing? If it's going inside the body, aim for absorbable. If it's at the skin, you have more options.
3) Follow-up: What is the likelihood this patient can return for follow-up suture removal? For pediatric patients who have already gone through the trauma of getting stitches and whose parents have already had to somehow coordinate a single ED visit while a gaggle of other responsibilities awaits them at home, or patients with poor access to healthcare at baseline, consider sparing them a second ED visit for suture removal and trial absorbable sutures when possible.
Your Suture Options
Materials
There are two big buckets of suture materials: absorbable and non-absorbable. Within each of those buckets you have two main sub-types: braided/multifilament and monofilament. Braided essentially means that there are multiple strands woven together, and monofilament means a single strand. The more the strands means the tighter the knot... but also the more surface area for inflammation and infection. I've stuck to just remembering the brand names of the sutures, but you might come across the generic names; use whatever works for you. For the absorbable sutures, note that there is often a discrepancy between when the suture loses its strength and when the suture actually absorbs/falls off.
1) Absorbable: braided/multifilament, monofilament
a. Braided/multifilament: vicryl, vicryl rapide
i. Vicryl: buried, loses strength 21d
ii. Vicryl rapide: irradiated to speed up resorption, buried or used in skin, loses strength 10d
b. Monofilament: fast absorbing gut, plain gut, chromic gut
i. Fast absorbing gut: used in skin, great for face ("F"ast for "F"ace), loses strength 7d
ii. Plain gut: used in skin, loses strength 8-9d
iii. Chromic gut: coated in chromium to slow down resorption, used in skin, great for hands or oral lacs, loses strength 10-21d
**Fun fact: gut is short for "catgut" sutures. Cat lovers, don't be afraid; our suture materials aren't actually coming from cats' guts. But they are coming from cow, pig, and sometimes horse intestines, all of which are known to be highly collagenous, elastic, and strong.**
2) Non-absorbable: braided/multifilament, monofilament
a. Braided/multifilament: silk
i. Silk: used in skin, great for securing chest tubes/drains, must be removed
b. Monofilament: ethilon, prolene
i. Ethilon aka Nylon: used in skin, black in color, must be removed, OUR GO-TO SUTURE
ii. Prolene: used in skin, blue in color, great for black hair/beards, must be removed
Sizes
For thin sutures (which is most of what we stock in the ED), the smaller the number, the bigger the physical size. These range from 1-0 (pronounced "one-oh") to 12-0 (pronounced "twelve-oh). 1-0 is the biggest, and 12-0 is the smallest. We will mainly use size 2-0 to size 6-0.
For thick sutures, it is the opposite; the smaller the number, the smaller the physical size. These range from 0-10 (no "-oh" afterwards). 0 is the smallest, and 10 is the biggest. We have size 0 silk in the ED, but the other sizes are mostly for the surgeons.
Needle Types
Straight or curved is the main distinction to know. Straight you can use with your hands to secure drains/tubes. Otherwise we are using curved with our needle drivers. (Pro tip: I once saw Dr. Masoudi make a curved needle out of a straight needle by physically bending it with a needle driver himself and it was extremely cool).
Removal
The importance of removing sutures isn't just for appearance purposes; it's to decrease the risk of an inflammatory reaction to the foreign body currently embedded in the skin. So the quicker we can get them out, the better. When giving return instructions to our patients, take into account the size and location of the suture. A good rule of thumb is the average suture removal length is 7d, but that shortens to around 5d closer to the face and extends to around 10-14d further towards the extremities. Suture Man is always a helpful resource, too.
Examples for Suture Choices at MMC
Uncomplicated laceration in an adult patient? Non-absorbable monofilament, ethilon or prolene, size 6-0 for face and size 3-0/4-0/5-0 everywhere else
Face laceration in a pediatric patient? Absorbable monofilament, fast absorbing gut, size 5-0
Trunk/extremities laceration in a pediatric patient? Absorbable braided or monofilament, vicryl rapide or plain gut, size 4-0 or 5-0
Deep laceration >3cm that requires buried sutures? Absorbable braided, vicryl, size 4-0
Oral laceration? Absorbable monofilament, chromic gut, size 3-0 or 4-0
Laceration within or around hair? Non-absorbable monofilament, prolene, size 3-0 to 6-0
Figure 8 suture for brisk/arterial bleeding? Non-absorbable monofilament, ethilon, size 2-0 is our biggest
Chest tube securing? Non-absorbable braided, silk (straight needle), size 0
For practice, try to find each of these suture types below on our trauma metal shelving unit in resus room 51...
I highly recommend downloading the Suture app (https://www.suture.app/) on your phone to use on shift, which is an interactive tool that will tell you the appropriate suture material, size, and removal time depending on the location and tension of the wound.
And, of course, we can't forget about skin glue (dermabond), steri strips, and the handy-dandy stapler. I am a die-hard fan of these quick, easy adjuncts for wounds that are low in tension and in an appropriate location for repair.
Happy suturing,
Kelsey
Resources:
1) https://canadiem.org/nice-threads-guide-suture-choice-ed/
2) https://www.ncbi.nlm.nih.gov/books/NBK539891/
4) https://coreem.net/core/suture-materials/
5) https://home.hippoed.com/blog/skin-deep-selecting-suture-material-for-the-skin-surface
6) https://www.aliem.com/pv-laceration-repair-and-sutures/
8) https://www.forbes.com/sites/quora/2018/09/26/what-is-catgut-really-made-from/