Laceration

Anatomy and Physiology

A basic understanding of the skin's anatomy can help determine the depth of a laceration. Knowledge of the stages of wound healing assists in patient education and follow-up care. The skin is made up of 3 layers:

1. Epidermis: most superficial layer, contains no nerve endings or blood vessels. There are 4 layers to the epidermis in all areas except in the palms of the hands and soles of the feet, where there are 5 layers.
2. Dermis: Contains nerves, vessels, glands, and connective tissue.
3. Fascia: a combination of connective tissue and adipose tissue.

The 4 stages of wound healing are:

1. Hemostasis begins immediately with the contracture of smooth muscles and tissue compressing small vessels. Platelets also begin to aggregate, activating the clotting cascade to produce initial fibrin clots.
2. Inflammation: Beginning immediately and lasting up to 30 days, Neutrophils activated through the complement cascade begin phagocytosis of dead tissue. After the first 72 hours, macrophages respond and continue phagocytosis for the duration of this stage.[1]
3. Proliferation: Beginning on day 7 and lasting several weeks, angiogenesis begins, accounting for the underlying erythema at the site. Fibroblasts begin to replace the inflammatory mass during this time, and collagen is laid down to replace fibrin clots.
4. Maturation: This stage begins after several weeks and can last from 6 to 12 months. Collagen is remodeled from type III to type I. At this stage, the scar should flatten, and the underlying erythema should resolve. Patients should be advised to massage the scar and avoid direct sunlight to reduce the risk of hyperpigmentation of the scar.

Indications

To best assess the future care requirements of any laceration, the healthcare team must first review the patient's history and thoroughly examine the wound and nearby structures. Pertinent history items include:

• Time of initial injury
• Location of laceration and extremity injuries have an increased risk of infection.
• Measurements of laceration, including length, width, and depth. As the depth and width of injuries increase, the risk of infection increases.[2]
• Mechanisms of injury include crush, sharp object, and shear from fall. Crush injuries with localized tissue injury have an increased risk of infection and scarring.[3]
• Age, because there is a risk of poor healing at the extremes of age.
• Past medical history, specifically any history of diabetes mellitus, chronic renal failure, obesity, malnutrition, or any use of immunosuppression drugs such as chemotherapy medications.[4]
• Allergies, specifically to latex, anesthetics, or antibiotics.
• For the immunization status, note the patient's tetanus vaccine history. Current guidelines for tetanus are:
  • Adults with greater than or equal to 3 previous tetanus doses:
    • Clean wounds: Tdap (tetanus, reduced diphtheria, pertussis) or Td (tetanus, reduced diphtheria) only if it has been over 10 years since their last vaccination.
    • Dirty/complex wounds: Tdap or Td if more than 5 years since their last vaccination.
  • Adults with under 3 previous tetanus doses:
    • All wounds: Tdap or Td required; if dirty/complex, they also require immunoglobulin treatment.
  • Children:
    • Under 7 years old: DTaP (diphtheria, tetanus, pertussis) vaccine is recommended; if pertussis is contraindicated, give the DT (diphtheria, tetanus) vaccine.
    • 7 to 9 years old: Td vaccine recommended.
    • Over 10 years old: Tdap is preferred in patients who have never received it and have no contraindications; if age or contraindications exist, use the Td vaccine.

Keys to a good physical exam of lacerations:

• Ensure appropriate lighting, gauze, and rinse materials are easily accessible before beginning the exam.
• Establish hemostasis: Hemostasis should be established to allow for visualization of underlying structures and foreign objects, utilizing direct pressure.
• Detailed neurologic exam: The clinician should perform a complete sensation exam at and below the level of injury before using any anesthesia to assess for any nerve injury. A quick method to evaluate for nerve injury is 2-point discrimination using a standard paper clip, always comparing to the patient's noninjured side.[5]
• Detailed musculoskeletal exam: Examine any joints involved in the laceration for injury, along with an active and passive range of motion exam above and below the joint to assess for tendon injury (see Image. Laceration of the Posterior Ankle Exposing the Achilles Tendon).
• Detailed Vascular exam: If the wound is on the extremities, assess the capillary refill distal to the wound and always compare it to the noninjured side. If accessible, Doppler ultrasound can assess underlying vascular integrity from above the laceration to below.
• If observed, foreign bodies should be removed, as they can increase the patient's risk of infection or poor wound healing. Imaging should be obtained if there is any concern about retained foreign bodies.

Contraindications

Contraindications to the repair of a laceration include:

• Bite wounds of any type
• Overt infections of the nearby skin
• Lacerations greater than 24 hours old

Equipment

The equipment required for closing lacerations can vary depending on the location and characteristics of the wound. Necessary supplies for any laceration repair include but are not limited to, the local anesthetic drawn up with a small gauge needle (greater than 27 gauge), needle holders, forceps, scissors, gauze, and the appropriate closure device (suture, staple, glue) for the wound. The selection of local anesthetic depends on patient allergies, accessibility, and location of the injury. True allergies to anesthetics are rare. If there is a concern for amide allergies, using ester anesthetics or preservative-free amides should be an option, as reactivity is thought to be due to the preservatives. The use of epinephrine with local anesthetic was previously cautioned in fingers, toes, nose, penis, and ears. However, current research shows that the concerns of local ischemia are unsupported.[6] The repair material selection varies based on the laceration's location, depth, length, and width. The decision between absorbable and nonabsorbable sutures depends on the depth and method planned for closure. Current studies have shown that selecting absorbable gut vs. nonabsorbable suture materials in the external closure of lacerations produces similar infection rates and aesthetic outcomes over the long term.[7]

Staples are used to close scalp lacerations quickly and securely. Staples are used to close scalp lacerations quickly and securely. Due to the higher risk of scarring, staples should only be used on thicker skin, and when appropriate, follow-up can be obtained for their removal.[8] Tissue adhesives can be an option when the laceration overlies an area with minimal tension and is easily approximated. The most significant concern for their use is the successful closure of the wound, which hinges on appropriate cleaning and preparation of the wound. Steri-strips are another alternative for the primary closure of lacerations with no tension and not overlying a joint. Still, due to the requirement of added adhesives such as benzoin, there is a risk of local skin reaction that reduces their functionality for laceration care.[9] Also of note is that many studies have examined using sterile vs. nonsterile gloves. Due to the contaminated nature of lacerations at presentation, there is no statistical difference in infection with nonsterile gloves.[10]

Personnel

The personnel requirements for the primary closure of a laceration vary depending on the complexity of the wound. A single provider can perform the technique alone in the most basic repairs. As the complexity of the laceration increases, other personnel may be needed to hold pressure, manage supplies, and reduce tension across the wound.

Preparation

A helpful mnemonic in preparing for any laceration is LACERATE[11]:

• L - Look at the wound to assess repair options
• A - Anesthetize the wound
• C - Clean the wound
• E - Equipment setup
• R - Repair the wound
• A - Assess the results, anticipate complications
• T - Tetanus Immunization
• E - Educate the patient about wound care

Careful step-by-step planning of the procedure and gathering all the required supplies ahead of time can help reduce the duration and difficulty of any closure. Preparing the room where the procedure takes place by turning on lights, moving trays and tables, positioning the patient's bed, and localizing waste receptacles all help reduce the risk of contamination during the procedure.

Technique or Treatment

Local anesthesia is used to clean and repair lacerations appropriately. As stated, the anesthetic selection depends on patient allergies and accessibility at the care facility. Several steps can be taken to reduce patient discomfort while administering the local anesthetic, such as:

• Buffering the solution at a rate of 9 mL of lidocaine to 1 ml of 8.4% sodium bicarbonate.[12]
• Warming the anesthetic to body temperature.[13]
• Small needles (greater than 27 gauge) were utilized to administer the anesthetic.
• Infusing the anesthetic slowly.
• Injecting through the edges of clean wounds vs. new punctures.[14]
• Utilizing topical anesthetics such as EMLA (eutectic mixture of local anesthetics) cream or TAC solutions (tetracaine, adrenaline, and cocaine) before infiltration with a local anesthetic.[15]
• Placing ice contained within a sterile glove over the injection site for 2 minutes before injection has been found to reduce pain from the local anesthetic.[16]

After local anesthesia, the next step is wound irrigation to remove any foreign objects and clotted blood, allowing for complete visualization of the laceration. Most commonly performed utilizing a saline solution, some research has shown that tap water can irrigate the wound in simple lacerations in healthy immunocompetent patients.[17] Following irrigation, the laceration can be closed using whichever method best suits its location and size. If suturing, there is no specific guide for which technique to use, but general technique recommendations are as follows:

• Simple interrupted sutures are versatile and the right choice for most wounds.
• Horizontal/ Vertical mattress sutures are utilized to evert wound edges but have an increased risk of scar formation.
• Deep sutures can reduce tension on the superficial sutures and help reduce future scarring. Still, due to the increased risk of infection, care must be taken to ensure the wound is clean before placing deep sutures.

Following primary closure, placement of either antibiotic ointment or petroleum-infused gauze over the sutures with overlying gauze affixed by tape is advised.[18] Educate patients on keeping the wound clean and give follow-up instructions for when they can have the sutures removed. General guidelines for removal vary depending on the repair's location, the repair's complexity, and the suture utilized. Sutures left in place too long can increase the risk of infection and scarring.

• General suture removal timelines:
  • Face: 3 to 5 days
  • Scalp and arms: 7 to 10 days
  • Trunk, Legs, hands, and feet: 10 to 14 days
  • Palms or soles: 14 to 21 days

Complications

The complications that van manifest with lacerations are as follows:

• Missed foreign bodies
• Missed tendon injuries
• Missed nerve injuries
• Infections
• Dehiscence of the wound[19]

Clinical Significance

Lacerations are a common chief complaint of patients, and the healthcare team must understand how to manage them to provide appropriate care.

Enhancing Healthcare Team Outcomes

Many clinicians see and manage lacerations. However, only those with anatomical and basic surgical knowledge should close them. Even the most simple laceration can become infected or develop into a keloid. Before closing any laceration, the wound must be clean. Laceration presentation can vary drastically, and while the primary care team can manage simple lacerations, the guidelines below should aid team decision-making on when to consult general surgery or other specialty services.

• Guidelines for when to seek surgical consultation:
  • Deep wounds on hands or feet
  • Full-thickness lacerations of eyelid, lip, or ear
  • Lacerations involving nerves, arteries, bones, or joints
  • Penetrating wounds of unknown depth
  • Severe crush injuries
  • Severely contaminated wounds requiring drainage
  • Wounds with substantial concern about the cosmetic outcome[20]

There are many instances where a laceration may not be safe to close, and in such situations, a wound care nurse should follow the patient. These patients require education about wound care and dressing changes. If the nurse notices complications such as infection or dehiscence, they should refer the patient back to the clinician. Nurses can work with applying and/or changing wound dressings and administering medication for pain control and antimicrobial agents. Pharmacists can make antibiotic recommendations for pain and perform medication reconciliation. If they become infected, the pharmacist should recommend antibiotics to the clinician based on local resistance, customs, and practices. The outcomes of laceration repair depend on the mechanism, location, and complexity. For optimal outcomes, prompt consultation with a specialist is recommended, and an interprofessional team approach must be leveraged for the best patient care and good outcomes.

Nursing, Allied Health, and Interprofessional Team Interventions

The prompt collection and dissemination of pertinent patient history can help the healthcare team assess the severity of the laceration. Understanding how to induce hemostasis through direct pressure appropriately can significantly aid in the complete assessment of the patient. Nurses also play a vital role in dressing changes, wound care, and timely removal of sutures/staples.

Nursing, Allied Health, and Interprofessional Team Monitoring

Nurses should monitor patients for the following signs:

• Hypotension (weakness, dizziness, pallor)
• Infection (fever, erythema, gross puss)
• Neurovascular injury (paresthesias, distal weakness, pulselessness, numbness)
• Signs of wound infection
• Adverse effects of the local anesthetic