Laceration Repair

 

Jeffrey N. Siegelman, MD

Key Points

• The timing of wound closure is determined by balancing

the risk of infection with the likelihood of scarring.

• Identify and remove foreign bodies before wound closure.

INDICATIONS

Any wound deeper than a superficial abrasion should be

considered for closure to improve the cosmetic result, preserve viable tissue, and restore tensile strength. This can be

accomplished with sutures, tissue adhesive, or staples.

Tissue adhesive may be indicated for hemostatic wounds in

low tension areas that are at low risk for infection. Staples

are appropriate for relatively linear lacerations located on

the extremities, trunk, or scalp.

CONTRAINDICATIONS

The decision about whether and when to repair a laceration is based on many factors, which can be divided

broadly into host and wound factors. Host factors include

age (elderly patients have 3-4 times higher rate of infection

and slower wound healing), malnutrition, and immunocomprornise ( eg, diabetes mellitus). Wound factors include

timing, location, mechanism, and contamination. Bacterial

counts begin to increase 3-6 hours post-injury, and every

attempt is made to achieve primary wound closure as

expeditiously as possible. However, there is no evidencedbased definitive time by which wounds must be closed.

Wounds of the face and scalp rarely become infected

( 1-2%) because the face and scalp have an excellent blood

supply; such wounds may be closed safely 24 hours or

more after injury. Infection rates of upper ( 4o/o) and lower

(7%) extremity wounds are higher, and many practitioners

20

• Evert wound edges for better aesthetic outcomes.

• Wound irrigation and debridement prevent wound

infections.

use 6-12 hours as a guideline for closing these wounds.

Lacerations sustained by a blunt, crushing force produce

more local tissue damage and therefore have a higher rate

of infection than lacerations caused by a sharp instrument

(ie, knife). A puncture wound also has a high rate of infection because bacteria are driven into the tissue and are

difficult to remove. Visible contamination within a wound

doubles the likelihood of infection. Bite wounds ( eg, dog,

cat, human) have a very high rate of infection owing to

bacterial colonization within the mouth. Generally, bite

wounds are not closed primarily unless the wound is gaping or in a cosmetically sensitive area (eg, face).

Staples and tissue adhesive should not be used on deep

wounds that would require multiple layered closure. Tissue

adhesives should not be used near mucosal surfaces, within

the scalp, or over joints (without immobilization), and care

must be taken when used near the eyes.

EQUIPMENT

When preparing the wound for closure, the following are

needed: povidone-iodine solution, local anesthetic ( 1 o/o

lidocaine with or without 1:100,000 epinephrine), 25- or

27-gauge needle, and a syringe. Irrigation is typically performed with normal saline or sterile water, a 60-mL

syringe, and an irrigation shield or 18-gauge angiocatheter;

however, some authors have argued that tap water is s uffi.­

cient for uncomplicated wounds. Similarly, sterile gloves

are typically used, although one study did not show

LACERATION REPAIR

Figure 6-1. Suture instruments. From left to right:

need le driver, tissue forceps (pick-ups), and scissors.

a decreased infection rate when sterile gloves were used

compared with clean gloves in the repair of clean wounds

less than 6 hours old. Instruments needed include a needle

driver, tissue forceps (pick-ups), and scissors (Figure 6-1).

Use the smallest monofilament suture available that will

adequately appose the ends of the laceration, because thinner suture causes less scarring. Usually 4-0 (largest, for

torso and extremities) to 6-0 (smallest, for face) will suffice. Antibacterial ointment, gauze, and tape are needed for

aftercare.

PROCEDURE

� Timing

Wound healing occurs by primary, secondary, or tertiary

intention. Primary intention is the most common method

of repair and involves the approximation of wound edges

soon after the injury with the use of sutures, staples, tape, or

tissue adhesive. In secondary intention, the wound is

cleaned but left open and allowed to heal spontaneously.

This method is used when the risk of infection after primary

closure is high. Tertiary intention (delayed primary closure)

decreases infection rate in highly contaminated wounds. It is

performed by cleaning and debriding contaminated wounds

acutely, then suturing the wound after 3-5 days.

� Wound Preparation

First, ensure adequate lighting and hemostasis to allow for

a complete evaluation. A thorough neurovascular examination is required for all wounds before administration of

local anesthesia. Tendon function must also be assessed,

when appropriate. Wound exploration may detect foreign

bodies and diagnose injuries to deeper structures. If the

depth of the wound is not easily appreciated and a foreign

body is suspected (ie, patient fell on broken glass), then a

plain radiograph is recommended. Glass fragments >2 mm

are almost universally visualized on plain radiographs.

Plastic and wood foreign bodies are not radiopaque and

may require further imaging (computed tomography scan,

ultrasound, or magnetic resonance imaging).

Lacerations through hair-covered surfaces require further preparation before proceeding with repair. Clipping

hair to 1-2 mm (but not shaving) or applying antibacterial

ointment to part hair away from wound edges will allow

better visualization during wound closure and decrease

risk of infection. Do not remove hair from eyebrows or the

hairline, as this can lead to impaired or abnormal regrowth.

The edges of the wound are prepped with povidoneiodine solution. Care should be taken not to get the solution

in the wound itself, as this inhibits healing. Draw up 1 o/o

lidocaine into a syringe and prepare to infiltrate using a 25-

or 27-gauge needle. Pain of injection can be reduced by

buffering the lidocaine with bicarbonate. To do this, mix

1 mL of sodium bicarbonate with 9 mL of 1 o/o lidocaine; this

solution must be used promptly. Lidocaine is infiltrated

within the wound edges and around the entire wound (field

block). In contaminated wounds, puncture the skin around

the laceration (theoretical lower risk of infection); in clean

wounds, puncture the wound edge within the wound itself

(decreases pain of injection). Remember, the maximum

dose of lidocaine without epinephrine is 4 mg!kg. This

equates to 280 mg in a 70-kg (154 lb) man or 28 mL of

1 o/o lidocaine ( 10 mgfmL). Lidocaine with epinephrine has a

maximum dose of 7 mg!kg. Other advantages of adding

epinephrine include decreased bleeding and increased dura ­

tion of anesthetic. Traditional teaching dictates that caution

should be used with epinephrine in end-arterial fields (eg,

fingers, toes) for patients with vascular injury or a history of

vascular disease; however, little evidence exists supporting

this practice.

Wound irrigation and debridement of devitalized tissues are the two most important ways to decrease the

incidence of wound infection. When irrigating a wound,

use a commercially available shield to avoid accidental

exposure to the health care worker and create the required

pressure to decrease bacterial counts. If unavailable, an

1 8-gauge angiocatheter with a 60-mL syringe can be used.

Irrigation with a saline bag or bottle with holes punched

into the top does not create enough pressure to adequately

reduce bacterial counts. The amount of saline required to

irrigate a wound is not known, but a basic guideline is to

use 50-100 mL for each 1 em of laceration.

� Wound Closure

A few principles should be considered when placing simple

interrupted sutures (Figure 6-2). Clamp the needle driver

CHAPTER 6

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Figure 6-2. Simple interru pted suture.

in the middle of the needle. Grasping the end of the

needle will damage the cutting edge and make suturing

more difficult. Insert the needle at 90 degrees to help

evert the tissue. Eversion permits more rapid epithelialization than inversion and avoids a scar that is depressed

after contraction. The tissue forceps are used to lift up the

skin on one side of the laceration. Grasping the tissue too

tightly (especially when using forceps with teeth) may

damage the tissue and should be avoided. Instead use the

teeth or a skin hook to lift the subcutaneous tissues.

When the needle is inserted, maintain the same depth as

the other side. Use 4-5 instrument ties to secure the knot.

Avoid pulling the wound edges too tightly (indicated by

blanching) because this may strangulate the wound

edges, reducing blood supply. Begin in the middle of the

wound, and then bisect the resulting segments with s ubsequent sutures until the wound is sufficiently approximated. As a rule, the distance from the needle insertion to

the wound edge should be the same on both sides, as well

as the same depth. The distance between stitches should

also be equal. On the face, this will be 1-3 mm and can be

farther apart elsewhere.

.

Vertical and horizontal mattress sutures both provtde excellent wound eversion and help to better

approximate wound edges that are under tension and

difficult to pull together (Figures 6-3 and 6-4). Vertical

mattress sutures are especially useful in lacerations in

which there is minimal subcutaneous tissue for deep

sutures such as the hands or over joints. In addition,

these sutures will help stop bleeding from a scalp laceration. The disadvantage of these sutures is that they may

strangulate the tissues.

Figure 6-3. Vertical mattress.

Deep sutures are indicated in wounds with multiple

layers of tissue to close ( eg, full thickness lip lacerations)

and to minimize tension on superficial skin for gaping

wounds. Deep sutures should be placed with absorbable

suture material. To get the knot to the depth of the wound,

make the first pass of the needle from the deep portion of

the wound to the superficial portion (Figure 6-5 ). Avoid

infection by placing only enough deep sutures to effectively

bring the wound edges together and cut the suture as close

to the knot as possible.

Staples are placed by first everting the edges of the

wound and then firing the automatic stapler with the same

principles of spacing as above.

Tissue adhesive is applied using 4-5 layers on a hemostatic, cleaned, dry wound, which the provider approximates while applying the adhesive. Avoid getting the

adhesive into the wound itself. Wound tape may be applied

to the wound before placing the adhesive to provide

improved approximation.

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.A. Figure 6-4. Horizonta l mattress.

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LACERATION REPAIR

Figure 6-5. Deep dermal stitch. On the first pass,

the needle enters at the depth of the wou nd so that

the knot wi ll end up at the bottom of the wound.

..... Wound Aftercare

Topical antibiotic ointments provide a moist environment

that assists epithelization and reduces the rate of infection.

They should not be used after the use of tissue adhesive.

Prophylactic oral antibiotics are r ecommended for heavily

contaminated wounds, significant animal or human bites,

areas prone to infection (mouth, plantar aspect of the

foot), open fractures, tendon or joint involvement, immunocompromised patients, a prosthetic heart valve, or deep

puncture wounds.

In patients with full childhood immunizations, tetanus

toxoid, given with diphtheria toxoid (Td 0.5 mL administered intramuscularly [IM) ), is administered after a minor,

clean wound if the last booster was > 10 years ago. In all

other wounds (contaminated, puncture, crush), tetanus

toxoid is given if the last booster was >5 years ago. Tetanus

immune globulin (TIG) 3,000-5,000U IM and around the

wound is administered to patients with a history of <3

immunizations and a contaminated wound.

Apply a topical ointment ( eg, bacitracin) and then a

sterile dressing. The dressing may be removed in 24 hours

and the wound can be gendy cleansed with soap and water,

using caution to blot the sutures dry.

Suture removal is recommended in 3-5 days for face

and neck; 7-10 days for upper extremity, chest, legs, and

scalp; and 10-14 days for hand, back, buttocks, foot, and

overlying joints.

COMPLICATIONS

Complications may include infection and scarring. Despite

all efforts to reduce the risk of infection, this complication

can still occur. The patient should be instructed to return

at the first signs of infection (ie, fever, purulent drainage,

or erythema). Patients with high-risk wounds should be

asked to return to their physician or the emergency department within 24-48 hours to have the wound reexamined

by a physician. Patients should also be instructed that a

scar will form with healing. Scarring is more significant

after deeper wounds, or those that do not run parallel to

natural skin lines, and when absorbable sutures are used.

There are insufficient data to recommend routine use of

topical healing creams such as vitamin E, aloe vera, or

other commercially available products.

SUGGESTED READING

Desai S, Stone SC, Carter WA. Wound preparation. In:

Tintinalli JE, Stapczynski JS, Ma OJ, Clince DM, Cydulka,

RK, Meckler GD. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 7th ed. New York, NY: McGraw-Hill, 20 1 1,

pp. 301-306.

Singer AJ, Hollander JE. Methods for wound closure. In:

Tintinalli )E, Stapczynski JS, Ma OJ, Clince DM, Cydulka, RK,

Meckler GD. Tintinalli's Emergency Medicine: A Comprehensive

Study Guide. 7th ed. New York, NY: McGraw-Hill, 20 1 1,

pp. 306-3 15.

Singer AJ, Hollander JE, Quinn JV. Evaluation and management

of traumatic lacerations. N Eng! J Med. 1997;337:1 142-1 148.