How to Suture: Simple Laceration Repair
Knowing how to suture is essential for a nurse practitioner or any provider — especially in emergency, urgent care, and family practice. Many NP students graduate without solid suture experience, and "are you comfortable suturing?" can make or break a job interview.
This full breakdown takes you from when to suture through tetanus, wound assessment, equipment, anesthesia, and the simple interrupted stitch — so you can suture with confidence.
When to Suture
Even if you know how to suture, recognize when to — suturing isn't always indicated. Sometimes other closure methods are better, and sometimes it's best to let a wound heal on its own (secondary intention).
Animal & Human Bites
Bites — including human bites, especially in non-cosmetic areas like the hands or feet — are high risk for infection and generally should not be closed. Delayed closure is even more strongly recommended in diabetics or those with venous stasis. Give rabies immunoglobulin and vaccine for bites from strays or unvaccinated animals that can't be quarantined.
Make Sure Tetanus Is Up to Date
Updating tetanus prevents the patient from developing tetanus — a disease of painful muscle stiffness and spasms after wound contamination. Ask when their last tetanus vaccination was (many patients won't know).
Give Tetanus Immune Globulin (TIg) If
The patient has had <3 tetanus vaccinations (or unknown) AND a contaminated/complex wound, or is HIV positive / severely immunocompromised. Contaminated = feces, soil, dirt, or saliva. Complex = puncture wounds, avulsions, crush injuries, or burns.
Perform an Appropriate Wound Assessment
A good laceration assessment is essential. Check distal neurovascular status and, in hand lacerations, tendon function — confirm full ROM distal to the injury and that no tendons are lacerated or visible. Ensure the wound isn't infected or grossly contaminated, look for foreign bodies, control bleeding, and measure length, width, and depth.
Equipment & Choosing Your Suture
Before suturing, gather everything to irrigate, clean, anesthetize, suture, and dress the wound.
- Nylon: high tensile strength, elastic, minimal reactivity, low cost, 3–4 knot throws.
- Polypropylene (Prolene): high tensile strength, low reactivity, 4–5 knots; blue version helps in scalp or dark skin.
- Polybutester (Novafil): similar but more elastic — useful if wound edema is expected.
- Silk: weaker, more reactive, still used for central lines and chest tubes.
- Chromic gut: tensile strength 10–14 days; common for oral mucosa; more reactive subcutaneously.
- Vicryl: tensile strength 3–4 weeks, full absorption 60–90 days — ideal for subcutaneous sutures.
- Vicryl Rapide: tensile strength 10–14 days, "falls off" in 7–10 days; useful under casts and as a nonabsorbable alternative.
Suture size sets the needle and thread thickness — the larger the number, the smaller the suture (1-0 largest, 10-0 smallest). Most simple repairs use 3-0 to 6-0, chosen by location:
Choosing the Anesthetic
You'll need to numb the area before sticking a needle through skin repeatedly. The main decision is lidocaine with or without epinephrine.
Epinephrine in Digits
Lido with epi was traditionally avoided in fingers, nose, and ears over necrosis fears, but the evidence is lacking and UpToDate now considers it acceptable. Still avoid injecting the digits with epinephrine-containing lidocaine in patients with peripheral vascular disease.
The Suturing Procedure
With suturing indicated, tetanus updated, and the wound assessed, you're ready. This covers the simple interrupted suture — appropriate for most simple lacerations.
Place 1–2 absorbable pads and have gauze ready. Briefly clean the surface with an alcohol wipe or diluted Betadine (1:10 with NS) — not Betadine surgical scrub, which is toxic to the wound. Draw lidocaine with a blunt needle, switch to a 25–30g needle, and infiltrate the dermis just inside the wound edge; you'll see the skin swell. Work around the wound, reusing freshly numbed tissue. For distal digits, a digital block is usually best.
Irrigation clears debris and prevents infection — generally 50–100 cc per cm. Fill a 30–60 cc syringe from a sterile NS bottle (or tap water), attach an 18g catheter for pressure, and flush the wound, catching runoff in a kidney basin. A splash guard prevents splashback. Measuring the wound is easier once cleaned.
RCTs show clean gloves don't raise infection rates over sterile, but sterile technique remains the "standard." Open the kit sterilely, drop sutures and any extra gauze onto the field, then remove clean gloves, wash your hands, apply sterile gloves, and set up your drapes.
Confirm bleeding has stopped (to avoid hematoma). Insert the needle at a 90° angle, starting ~5 mm from the edge, 5 mm deep, exiting 5 mm on the other side (2.5 mm for facial lacerations). Place the first suture in the center — it often takes two bites. Pull through, leaving a short tail, then tie a square knot using the needle driver: two loops on the first throw, one loop on subsequent throws, pulling the knot to one side of the wound. Use roughly the same number of throws as the suture size (3 for 3-0, etc.). Cut both ends ~5 mm.
Place each next stitch ~5 mm from the last (2.5 mm on the face), or bisect each remaining side until the wound is closed. Do most pulling with the long tail and your hand to avoid wasting suture.
Dress the Wound
Once closed, apply bacitracin or Neosporin directly to the wound, then a nonadherent dressing — a Telfa pad covered with dry gauze and wrapped with Kerlix works well. For small lacerations (especially the face), even a simple bandage is fine.
Discharge Instructions & Follow-Up
Good discharge instructions matter, since there's usually meaningful follow-up. Tell the patient to leave the dressing in place 24–48 hours, then open to air (cover it if contamination is likely, e.g., at work). Nonabsorbable stitches can be cleaned gently with soap and water twice a day; half-strength hydrogen peroxide twice daily prevents crusting (especially on the face). An OTC antibiotic or white petroleum ointment twice daily can promote healing and reduce scarring. Avoid submerging the wound until healed.
When to Add Antibiotics & Early Follow-Up
A wound check in 2–3 days is recommended for any redness, swelling, or discharge — and regardless in high-risk patients (diabetes, chemo, renal disease) or highly contaminated wounds. Prophylactic PO antibiotics are reasonable for contaminated wounds, animal/human bites, vascular insufficiency, or immunocompromise.
Clinical Pearls
Related Guides
References
- Closure of minor skin wounds with sutures. UpToDate.
- Minor wound preparation and irrigation. UpToDate.
- Subcutaneous infiltration of local anesthetics. UpToDate.
- Animal bites: evaluation and management. UpToDate.
- Tetanus-diphtheria toxoid vaccination in adults. UpToDate.
- Tintinalli J, et al. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 8th ed, Ch. 41.
- Buttaravoli P, Leffler S. Minor Emergencies. 3rd ed, Ch. 143.
- Sterile versus nonsterile gloves for repair of uncomplicated lacerations: a randomized controlled trial. PubMed.
good information, I enjoyed reading. i have one question though. if i only have lidocaine and epinephrine separate can i inject them seperate in order to contoll the bleeding?
I wouldn’t recommend mixing epi and lido yourself unless there is a specific facility protocol you are following. I would use the pre-mixed vials. But yes you can use inject it to control local bleeding.
I am a high school Healthcare Science teacher. My upper level class is allowed to learn basic suturing. I was looking or an easy way to explain suturing and how to do it. What a great resource! This was easy to follow and very detailed. Thank you so much for sharing.
I love that! Thanks for using the site and I hope it’s useful to your class!
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