Facial Lacerations

1. Clinical Overview

Facial Lacerations represent a unique challenge in acute care medicine, sitting at the intersection of trauma management and cosmetic surgery. Unlike wounds elsewhere on the body, the primary goal is not just closure, but cosmetic excellence. The face is central to human identity and communication; even minor scarring can have profound psychological and social consequences for the patient.

Facial lacerations account for approximately 8-12% of all emergency department visits for traumatic injuries, with peak incidence in males aged 20-40 years. [1] The management of facial trauma requires a precise understanding of the complex 3D anatomy of the face. "Simple" lacerations can harbor occult injuries to critical structures such as the facial nerve, the parotid duct, or the lacrimal drainage system. A missed injury in these zones is catastrophic, leading to permanent paralysis, salivary fistulas, or chronic tearing.

The Golden Rule: The rich vascular supply of the face is a double-edged sword. It allows for "permissive" closure times (up to 24 hours) and the survival of narrow flaps that would die elsewhere. However, it also means profuse bleeding that can obscure deep pathology. Hemostasis and unhurried exploration are mandatory. Studies demonstrate that facial wound infection rates remain below 2% even with delayed closure up to 24 hours post-injury, compared to 8-12% for truncal wounds. [2]

Critical Alerts (The "Do Not Miss" List)

1. Facial Nerve Palsy: Any laceration along the course of the facial nerve requires documented motor testing before local anaesthetic is injected.
2. Parotid Duct Injury: Lacerations crossing the middle third of the cheek may sever the duct (Stenson's duct).
3. Eyelid Margin Involvement: Failure to align the grey line results in notching and trichiasis (eyelashes scratching the cornea).
4. Vermilion Border Misalignment: A step-off of > 1mm is visible from a conversational distance and produces significant cosmetic deformity.
5. Septal Hematoma: Following nasal trauma, always look inside the nose. A hematoma can destroy the septal cartilage (Saddle Nose Deformity) within 24-72 hours.
6. Lacrimal System Injury: Any medial canthal laceration requires ophthalmology assessment to exclude canalicular injury.

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2. Epidemiology

Facial lacerations represent a significant burden on emergency healthcare systems globally:

Risk Factors for Complications

• Delayed presentation (> 24 hours): Increased infection risk
• Contaminated wounds: Soil, organic matter, saliva (bite wounds)
• Crush injuries: Tissue devitalization, higher scarring rates
• Substance intoxication: Associated with mechanism, affects wound care compliance
• Immunocompromise: Diabetes, steroids, chemotherapy
• Anticoagulation: Warfarin, DOACs increase hematoma risk

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3. Anatomy and Critical Structures

The face is a topographical minefield. Safety depends on knowing where the "mines" are buried.

3.1 The Layers of the Face

Understanding the layered anatomy is essential for proper wound exploration and closure:

1. Epidermis/Dermis: The cosmetic layer. Facial skin varies in thickness (eyelid 0.5mm vs forehead 1.5-2mm).
2. Subcutaneous Fat: Provides contour and mobility. Variable thickness across facial regions.
3. SMAS (Superficial Musculo-Aponeurotic System): A distinct fibrous layer enveloping facial muscles.
   • Surgical Relevance: This is the high-tension layer. Deep sutures must anchor here to take tension off the skin. If you close the skin under tension, the scar will widen.
4. Facial Nerve (CN VII): Runs DEEP to the SMAS (mostly) within the parotid gland, becoming more superficial as it branches distally.
5. Vascular Supply: The Facial Artery (from External Carotid) provides robust collateral flow, explaining the permissive closure window.

3.2 The Muscles of Facial Expression (Detailed)

Unlike skeletal muscles, facial muscles insert into the skin, allowing for nuanced expression. Lacerations often transect these muscles, requiring deep layer repair for functional and cosmetic restoration.

3.3 The Danger Zones (Pitanguy's Lines)

The Temporal Danger Zone (Frontal Branch of CN VII)

The nerve that lifts the eyebrow runs superficially in the temple.

• Surface Landmark: Draw a line from the Tragus to the Lateral Canthus. Draw another line from the Tragus to the highest forehead crease. The "Danger Zone" is the triangle between these lines.
• Anatomy: The frontal branch crosses the zygomatic arch approximately 1.5-2cm anterior to the external auditory canal. [4]
• Consequence: Interruption causes brow ptosis (inability to raise the eyebrow), leading to visual field obstruction and facial asymmetry.

The Mandibular Danger Zone (Marginal Mandibular Branch of CN VII)

This nerve powers the lip depressors.

• Course: It drops below the angle of the jaw in ~20% of patients before curving back up to the lip corner. [4]
• Safe Zone: The nerve lies superior to the inferior border of the mandible in the anterior face.
• Consequence: Asymmetric smile (inability to show lower teeth). The lip rides high on the affected side.

The Parotid Zone (Stenson's Duct & Buccal Branch)

• Surface Landmark: A line drawn from the Tragus to the Mid-Philtrum (middle of upper lip). The duct (and the Buccal branch of CN VII) runs along the middle third of this line.
• Anatomy: The duct is 5-7cm long, 3-4mm diameter, crosses the masseter muscle, pierces the buccinator, and opens into the oral cavity opposite the upper 2nd molar.
• Test: Cannulate the duct (papilla opposite the Upper 2nd Molar) or press on the gland to see if saliva leaks into the wound.
• Consequence: Unrepaired duct injury leads to salivary fistula or sialocele formation.

The Medial Canthal Zone (Lacrimal Apparatus)

• Anatomy: The Lacrimal Canaliculi drain tears from the eyelids to the nose. They run in the medial 5-8mm of the upper and lower lids.
• Rule: Any laceration medial to the punctum (tear duct opening) needs probing by ophthalmology. Missed injury causes permanent tearing (Epiphora).
• Repair: Requires microsurgical repair with stent placement, typically performed by ophthalmology or oculoplastic surgery.

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4. Clinical Assessment

4.1 History and Risk Stratification

• Mechanism:
  • Shear (Glass/Razor): Clean edges. Low energy. Best outcome.
  • Crush/Burst (Punch/Fall): Edges are exploded and devitalized. High energy. High scarring risk.
  • Avulsion (Dog Bite): Tissue loss. High infection risk (10-20% for bites vs 1-2% for clean lacerations). [5]
• Timing:
  • Face: Primary closure acceptable up to 24 hours for clean wounds, potentially longer for selected cases. [2]
  • Body: Usually less than 6-12 hours for primary closure.
  • Delayed Primary Closure: Consider for contaminated wounds presenting at 12-24 hours.
• Tetanus Status:
  • If less than 3 doses total: Needs Full Course + Immunoglobulin for tetanus-prone wounds.
  • If Fully Immunised (> 3 doses) but last booster > 10 years (clean) or > 5 years (dirty): Needs Booster.
• Rabies Risk: Assess for animal bites, particularly dog, cat, bat, or wild animal exposures.

4.2 Physical Examination (The Functional Exam)

CRITICAL STEP: You must assess nerve function BEFORE injecting local anaesthetic. Once numb, paralysis is iatrogenic until proven otherwise.

Cranial Nerve VII (Facial) Motor Exam

Test all 5 branches systematically:

1. Temporal: "Raise your eyebrows to the ceiling." (Check Frontalis).
2. Zygomatic: "Squeeze your eyes shut tight." (Check Orbicularis Oculi).
3. Buccal: "Show me your teeth" or "Puff out your cheeks." (Check Buccinator/Zygomatics).
4. Marginal Mandibular: "Show me your bottom teeth" or "Do a sad face." (Check Depressor Anguli Oris).
5. Cervical: "Clench your neck." (Check Platysma).

Documentation: Record specific findings (e.g., "Patient able to raise both eyebrows symmetrically, close eyes against resistance, show all teeth without asymmetry") rather than generic "CN VII intact."

Cranial Nerve V (Trigeminal) Sensory Exam

Test sensation to light touch in all three divisions:

• V1 (Ophthalmic): Forehead.
• V2 (Maxillary): Cheek/Upper Lip. (Infraorbital nerve often injured).
• V3 (Mandibular): Chin/Lower lip. (Mental nerve).

Sensory deficits may indicate nerve transection or compression from hematoma.

Specific Structure Tests

• Levator Palpebrae (Upper lid): "Look up and down." Check for ptosis.
• Parotid Duct: Dry the wound. Massage the parotid gland. Look for saliva pooling in the wound. If uncertain, cannulate the intraoral papilla opposite the upper 2nd molar.
• Orbital Rim: Palpate for "step-offs" (fractures) along the bony rim. Consider imaging if tenderness or deformity present.
• Septal Hematoma: Look inside the nose with nasal speculum for boggy purple swelling on the septum. Requires urgent drainage.
• Dental Examination: Check for loose, fractured, or missing teeth. Fragments may be embedded in soft tissue.

4.3 Wound Assessment

• Length and Depth: Measure and document. Deep lacerations require layered closure.
• Tissue Viability: Assess edges for contusion, devitalization, or ischemia.
• Contamination: Document presence of foreign material, soil, organic matter.
• Foreign Bodies: High index of suspicion for glass, gravel, tooth fragments.

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5. Anaesthesia and Pain Control

Pain anxiety results in poor patient cooperation and poor cosmetic outcomes. Definitive anaesthesia (regional nerve blocks when possible) allows the operator to work with precision and calmness.

5.1 Pharmacology of Local Anaesthetics

Lidocaine (Lignocaine) - The Gold Standard

• Concentration: 1% (10mg/ml) or 2% (20mg/ml).
• Onset: Rapid (less than 2 minutes).
• Duration: 30-60 minutes (Plain) vs 2-4 hours (with Epinephrine).
• Max Dose: 3mg/kg (Plain) vs 7mg/kg (with Epinephrine). For a 70kg patient: 210mg plain (21ml of 1%) or 490mg with epi (49ml of 1%).
• Role of Epinephrine (Adrenaline):
  • Vasoconstriction: Critical for hemostasis. Turns a bloody field into a dry field, improving visualization.
  • Prolongs Duration: Delays systemic absorption, extending anaesthetic effect.
  • Safety Check: Safe for use in the face, nose, ear, and digit. The historical dogma of "no epinephrine in end-arteries" has been disproven. [6]
  • Contraindications: Pheochromocytoma, severe uncontrolled hypertension.

Bupivacaine (Marcaine) - The Long Actor

• Concentration: 0.25% (2.5mg/ml) or 0.5% (5mg/ml).
• Onset: Slow (5-10 minutes).
• Duration: 4-8 hours.
• Max Dose: 2mg/kg (Plain) vs 2.5mg/kg (with Epinephrine).
• Use Case: Great for "painless discharge". Perform the repair with Lidocaine (fast onset), then infiltrate Bupivacaine at the end for post-procedure analgesia.

The "Ouch-Less" Injection (Buffering)

Local anaesthetics are packaged at pH 3.5-5.0 (acidic) to preserve shelf life. This acid causes the "sting" of injection.

• Recipe: 9ml Lidocaine + 1ml Sodium Bicarbonate (8.4%).
• Effect: Neutralizes pH to ~7.4. Reduces pain scores by > 50% and speeds onset. [7]
• Technique: Even with buffering, inject slowly (1ml over 10 seconds). Rapid distention of tissue causes pain. Use a 30G or smaller needle.
• Additional Strategies: Warm the anaesthetic to body temperature, inject through wound edges rather than intact skin when possible.

5.2 Local Anaesthetic Systemic Toxicity (LAST)

Though rare in facial blocks properly performed, inadvertent intravascular injection into the Facial Artery or absorption of excessive doses can cause seizures and cardiac arrest.

Signs of Toxicity (Progressive):

• Early (CNS Excitation): Perioral tingling, Metallic taste, Tinnitus (ringing in ears), Lightheadedness.
• Intermediate (CNS Depression): Visual disturbances, Slurred speech, Confusion, Drowsiness.
• Late (CNS/CVS Collapse): Seizures, Coma, Cardiac Arrhythmias, Cardiac Arrest (CV Collapse).

Management Protocol (Lipid Rescue):

1. Stop Injection immediately. Call for help.
2. Airway: 100% Oxygen. Ensure patent airway. Hyperventilate to prevent acidosis (acidosis worsens toxicity by increasing ionized drug fraction).
3. Benzodiazepines: Midazolam 2-5mg IV for seizures. Avoid propofol (cardiotoxic).
4. Intralipid 20% Emulsion (Lipid Rescue Therapy):
   • Bolus: 1.5 ml/kg over 1 minute (approximately 100ml for 70kg patient).
   • Infusion: 0.25 ml/kg/min (approximately 15ml/min for 70kg).
   • Repeat Bolus: If cardiovascular instability persists, repeat bolus and increase infusion to 0.5ml/kg/min.
   • Maximum Dose: Approximately 12ml/kg over 30 minutes.
   • Effect: Acts as a "lipid sink" to absorb the lipophilic anaesthetic molecules from the heart and brain, redistributing them to less critical tissues.
5. CPR: Continue prolonged resuscitation if required. LAST patients have survived after > 1 hour of CPR with lipid therapy.

5.3 Regional Nerve Blocks (The "Master Class")

Infiltrating directly into a wound distorts the anatomy (ballooning) and hinders precise alignment. Nerve blocks provide wide-field anaesthesia with zero distortion, superior for complex repairs requiring meticulous technique.

1. Supraorbital & Supratrochlear Block (The "Forehead Field")

• Indication: Lacerations of the forehead, anterior scalp, or upper eyelid.
• Anatomy: Nerves exit the skull at the supraorbital rim.
  • Supraorbital Notch: Palpable on the rim, in line with the pupil (mid-pupillary line), approximately 2.5cm from midline.
  • Supratrochlear Nerve: 1cm medial to the notch (near the nose).
• Technique:
  1. Palpate the Supraorbital Notch.
  2. Insert 27G needle just above the eyebrow, lateral to the notch.
  3. Advance medially towards the glabella, injecting a "band" of anaesthetic (3-5ml total) subcutaneously across the entire brow.
  4. Alternatively, inject 2ml at each nerve exit point (supraorbital and supratrochlear).
• Result: Numbness of the entire hemiforehead extending posteriorly to the vertex.
• Onset: 5-10 minutes for full effect.

2. Infraorbital Block (The "Mid-Face Mask")

• Indication: Lacerations of the cheek, upper lip, lateral nose, and lower eyelid.
• Anatomy: Infraorbital nerve exits the Infraorbital Foramen.
  • Location: Mid-pupillary line, approximately 1cm below the inferior orbital rim.
• Technique (Intra-Oral Approach - Preferred):
  1. Lift the upper lip.
  2. Insert needle into the buccal mucosa (gum) just above the Canine (Eye tooth), adjacent to the canine fossa.
  3. Aim superiorly towards the pupil. You can palpate the foramen externally with your non-dominant hand to guide the needle tip.
  4. Inject 2-3ml near the bone. Avoid entering the foramen itself (can cause nerve damage).
• Technique (External Approach):
  1. Palpate the infraorbital foramen below the orbital rim.
  2. Insert needle through skin inferior to foramen.
  3. Direct needle superiorly and inject 2-3ml around nerve.
• Result: Profound numbness of the ipsilateral upper lip, lateral nose, lower eyelid, and cheek (the "snout" region).

3. Mental Nerve Block (The "Goatee Zone")

• Indication: Lacerations of the lower lip, chin, and anterior mandibular mucosa.
• Anatomy: Mental nerve exits the Mental Foramen.
  • Location: Mid-pupillary line (in children) or between the 1st and 2nd Premolars (adults), approximately 1cm superior to the inferior border of the mandible.
• Technique (Intra-Oral Approach - Preferred):
  1. Pull the lower lip down and out.
  2. Insert needle into the buccal sulcus at the root of the 2nd Premolar or between 1st and 2nd premolars.
  3. Direct needle toward the mental foramen and inject 2-3ml.
• Result: Numbness of the ipsilateral lower lip, chin, and anterior mandibular gingiva.

4. Auricular Block (The "Ring Block")

• Indication: Lacerations of the ear (pinna) or complex cartilage repairs.
• Anatomy: The ear is supplied by the Auriculotemporal (top), Lesser Occipital (back), and Great Auricular (lobe) nerves.
• Technique:
  1. You must block the entire base of the ear (360 degrees infiltration).
  2. Start below the lobule. Inject subcutaneously upwards behind the ear (posterior auricular).
  3. Inject upwards in front of the ear (pre-auricular, in front of tragus).
  4. Inject over the top of the ear (superior auricular).
  • Shape: You are drawing a "Diamond" or "Ring" around the ear base, infiltrating all approaches.
• Volume: Requires approximately 5-8ml total.
• Caution: Avoid injection directly into cartilage.

5. Dorsal Nasal Block

• Indication: Nasal tip or bridge lacerations.
• Anatomy: Supplied by infratrochlear, external nasal, and infraorbital nerve branches.
• Technique:
  1. Inject along the midline of the nose (dorsum) from root to tip (2-3ml).
  2. Inject laterally at the alar bases bilaterally (1-2ml each side).
  3. Consider infraorbital block for more extensive anaesthesia.
• Result: Anaesthesia of nasal bridge and tip.

5.4 Procedural Sedation & Anxiolysis

For children, highly anxious adults, or extensive complex repairs, local anaesthesia alone may be insufficient.

• Topical (LET or LAT Gel): Lidocaine-Epinephrine-Tetracaine.
  • Action: Apply gel directly to wound, cover with occlusive dressing. Wait 30 minutes.
  • Effect: Often provides complete anaesthesia for scalp/face lacerations for staples, glue, or simple suturing without any needles.
  • Limitation: Less effective for deep repairs requiring extensive undermining or deep sutures.
• Nitrous Oxide (Entonox 50%/50% N2O/O2): Excellent for short procedural pain and anxiety.
  • Route: Self-administered inhalation via mask.
  • Onset: 30-60 seconds.
  • Benefit: Anxiolysis, mild analgesia, rapid offset. Patient remains conscious and cooperative.
• Ketamine Dissociation: Procedure of choice for complex facial repairs in children requiring complete immobility.
  • Dose: 1-1.5 mg/kg IV (rapid onset) or 3-4 mg/kg IM (slower onset, 3-5 minutes).
  • Benefit: Provides dissociative anaesthesia (cataleptic state) while preserving airway reflexes, respiratory drive, and cardiovascular stability.
  • Monitoring: Requires continuous monitoring, capnography, and immediate airway management capability.
  • Recovery: Emergence reactions (hallucinations, agitation) occur in 10-20% of children, reduced by benzodiazepine premedication and quiet recovery environment.

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6. Wound Preparation and Exploration

6.1 Irrigation (The "Solution to Pollution")

Copious irrigation is the single most important factor in reducing wound infection rates. [8]

• Volume: Minimum 200ml per cm of laceration length. For a 5cm facial laceration, use at least 1000ml (1 liter).
• Solution: Normal saline (0.9% NaCl) or tap water are equivalent in infection rates. Tap water irrigation is safe, effective, and cost-efficient. [8]
• Pressure: Moderate pressure (5-8 psi) is optimal. Achieved with:
  • 35-60ml syringe with 18G or 19G needle/catheter
  • Commercial wound irrigation system
  • Bulb syringe (lower pressure, acceptable for facial wounds to avoid tissue damage)
• Technique: Direct stream into wound, allowing fluid to exit and carry debris. Avoid splash contamination of eyes.
• Caution: Avoid high-pressure irrigation directly into delicate structures (eyes, exposed nerve/tendon).

6.2 Debridement

• Principle: Remove devitalized tissue, foreign material, and heavily contaminated tissue.
• Conservative Approach on Face: The excellent vascularity of the face means tissue that appears marginally viable often survives. Err on the side of conservation.
• Sharp Debridement: Use fine scissors or scalpel to excise clearly nonviable tissue (grey, non-bleeding edges).
• Tissue Sparing: Avoid routine "freshening" of wound edges on the face. This converts a clean wound into a larger surgical wound and removes tissue that may heal.

6.3 Foreign Body Detection and Removal

Missed foreign bodies are a common cause of infection, delayed healing, and litigation. [9]

• High-Risk Wounds: Glass injuries (windshield, bottles), road rash/gravel, explosions, industrial accidents.
• Detection Methods:
  • Visual Inspection: Under good lighting, with wound edges spread apart.
  • Palpation: Gentle probing with gloved finger or instrument.
  • Radiography: X-ray detects glass > 2mm, metal, gravel, some plastics. Obtain 2 views. Consider soft tissue technique.
  • Ultrasound: Highly sensitive for radiolucent foreign bodies (wood, plastic). Operator-dependent.
  • CT Scan: Gold standard for complex wounds or suspected deep foreign bodies, especially periorbital.
• Documentation: If foreign body suspected but not found, document thorough exploration and inform patient of possibility of retained material.

6.4 Hemostasis

• Direct Pressure: First-line for most bleeding. Apply for 5-10 minutes with gauze soaked in epinephrine-containing local anaesthetic.
• Selective Cautery: Bipolar electrocautery for specific bleeding points. Use lowest effective setting to minimize thermal tissue damage.
• Ligation: For larger vessels, ligate with fine absorbable suture (5-0 or 6-0 Vicryl).
• Topical Hemostatic Agents: Gelatin sponge (Gelfoam), oxidized cellulose (Surgicel), or topical thrombin for persistent oozing.
• Caution: Avoid excessive cautery on the face (causes tissue necrosis and poor scarring). Avoid cautery near nerves.

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7. Closure Techniques & Suture Biomechanics

7.1 Principles of Facial Wound Closure

1. Tension-Free Skin Closure: All tension should be borne by deep (dermal/SMAS) layer, not skin.
2. Eversion of Edges: Wound edges should be slightly everted (pouting outward). Inverted edges create a depressed scar.
3. Precise Edge Approximation: Edges should just touch ("kiss"), not overlap. Overlapping causes step-off.
4. Layered Closure: Close from depth to surface. Obliterate dead space to prevent hematoma.
5. Minimize Ischemia: Avoid excessive tension or tight sutures that strangulate tissue blood supply.

7.2 Suture Material Science

Choosing the right material balances tensile strength, tissue reactivity, handling, and absorption profile. [10]

Non-Absorbable Sutures (Skin Layer)

1. Nylon (Ethilon, Dermalon):
   • Type: Monofilament synthetic.
   • Pros: Minimal tissue reactivity, high tensile strength, excellent knot security, low cost.
   • Cons: Stiff (high memory - tendency to uncoil), ends can be sharp and irritating.
   • Verdict: The standard for facial skin closure (6-0 for most areas, 5-0 for scalp).
   • Removal: 3-5 days for face.
2. Polypropylene (Prolene):
   • Type: Monofilament synthetic.
   • Pros: Lowest tissue reactivity (ideal for contaminated/infected wounds), blue color (easy to see in hair/eyebrow), slippery (easy, painless removal).
   • Cons: Poor knot security (requires 4-5 throws), expensive, very stiff.
   • Verdict: Best for Eyelids and Eyebrows where low reactivity and visibility are critical.
   • Removal: 3-4 days for eyelids, 5 days for eyebrows.
3. Fast Absorbing Gut (Plain Gut):
   • Type: Natural (sheep/cow intestine), absorbs in 5-7 days.
   • Pros: Falls out spontaneously (no removal visit), ideal for children and non-compliant patients.
   • Cons: High tissue reactivity (causes inflammation, redness), lower tensile strength, less predictable absorption.
   • Verdict: Use selectively when suture removal is impractical. Accept slightly inferior cosmetic outcome for convenience.
   • Use: Mucosal surfaces, pediatric facial lacerations where suture removal is traumatic.
4. Silk:
   • Type: Natural braided.
   • Use: Generally avoided on face due to high tissue reactivity and infection risk (braided material wicks bacteria).
   • Exception: Occasionally used for through-and-through lip repairs (mucosa).

Absorbable Sutures (Deep Layer)

1. Polyglactin 910 (Vicryl):
   • Type: Braided synthetic (polyglactin 910).
   • Absorption: Loses 50% strength at 2-3 weeks, absorbed by 60-90 days.
   • Pros: Excellent handling (easy to tie, holds knots well), good tensile strength retention for 2-3 weeks (critical wound healing period).
   • Cons: Braided structure wicks bacteria (avoid in contaminated wounds).
   • Verdict: The standard for subcutaneous/muscle/SMAS closure on face (4-0 or 5-0).
2. Poliglecaprone 25 (Monocryl):
   • Type: Monofilament synthetic.
   • Absorption: Loses 50% strength at 1 week, absorbed by 90-120 days.
   • Pros: Monofilament (lower infection risk than braided), low tissue reactivity, good for dermal closure.
   • Cons: Stiffer, harder to handle and tie than Vicryl. Loses strength faster.
   • Verdict: Excellent for deep dermal layer and contaminated wounds where monofilament preferred. Requires more throws for secure knot (4-5).
3. Polydioxanone (PDS II):
   • Type: Monofilament synthetic.
   • Absorption: Retains 50% strength at 4-6 weeks, absorbed by 180-210 days.
   • Pros: Prolonged strength retention, monofilament.
   • Cons: Stiff, difficult to handle, slower absorption.
   • Verdict: Reserve for areas under high tension requiring prolonged support (scalp, forehead galea). Generally too stiff for routine facial work. Use 4-0 or 3-0.
4. Polyglactin 910 Rapid (Vicryl Rapide):
   • Type: Braided synthetic, irradiated for rapid absorption.
   • Absorption: Loses strength at 7-10 days, absorbed by 42 days.
   • Pros: Rapid absorption, good for mucosal surfaces and pediatric skin (where early absorption desired).
   • Cons: Loses strength too quickly for deep structural support.
   • Verdict: Ideal for intraoral mucosa (through-and-through lip), pediatric facial skin closure. Use 5-0 or 4-0.

7.3 Suture Size Selection

7.4 Advanced Suture Techniques

1. The Deep Dermal Stitch (Buried Vertical Mattress / "Buried Dermal Suture")

• Goal: To take 100% of the tension off the skin edges, allowing skin sutures to be placed with minimal or no tension.
• Indication: All facial lacerations requiring layered closure (essentially all lacerations >superficial dermis).
• Technique:
  1. Use absorbable suture (4-0 or 5-0 Vicryl or Monocryl).
  2. Enter the deep dermis from the bottom of one wound edge (at the level of the subcutaneous-dermal junction).
  3. Exit in the superficial (papillary) dermis, just below the skin surface (1-2mm).
  4. Cross to the opposite side.
  5. Enter the superficial dermis (mirror image of exit point on opposite side).
  6. Exit at the deep dermis (mirror of entry point).
  7. Tie the knot. The knot will be buried at the bottom of the wound, pulling the deep tissues together.
  8. Result: The skin edges should spontaneously approximate or "kiss" without any tension. The skin sutures simply align the edges precisely.
• Mnemonic: "Deep-to-Superficial, Superficial-to-Deep" on each side.
• Effect on Scarring: By eliminating tension on the skin layer, the skin sutures can be removed early (day 3-5) without risk of dehiscence, minimizing suture track marks ("railroad tracks"). [10]

2. The Simple Interrupted Suture (Standard Skin Closure)

• Goal: Precise edge-to-edge approximation.
• Technique:
  1. Use non-absorbable suture (6-0 Nylon for most facial areas).
  2. Enter skin 2-3mm from wound edge, perpendicular to skin surface.
  3. Pass through dermis and subcutaneous tissue in an arc (wider at depth than at surface to promote eversion).
  4. Exit on opposite side, mirror image of entry.
  5. Tie with instrument tie using 3 throws (2 for first throw, 1 for second and third).
  6. Tighten just enough to approximate edges. Edges should touch, not blanch white (indicates ischemia).
• Spacing: 3-5mm apart on face.

3. The Vertical Mattress (The Evertor)

• Goal: To forcefully evert wound edges that have a tendency to invert.
• Indication: Concave surfaces (neck, posterior auricular), wounds under tension, or wounds with tendency to invert.
• Technique ("Far-Far, Near-Near"):
  1. Use non-absorbable suture (5-0 or 6-0 Nylon).
  2. Far Bite: Enter skin 5-8mm from wound edge, pass deep through subcutaneous tissue, exit 5-8mm on opposite side.
  3. Loop back on same side.
  4. Near Bite: Enter skin 2mm from edge (superficial dermal bite), exit 2mm on opposite side.
  5. Tie. This creates a two-level bite that everts edges.
• Caution: Produces more tissue trauma and suture marks than simple interrupted. Remove at 5 days maximum.
• Modification: "Half-buried vertical mattress" (one side buried) for even less surface marking.

4. The Horizontal Mattress (High Tension Situations)

• Goal: To distribute tension over a wider area.
• Indication: Scalp lacerations, wounds under high tension, hemostasis.
• Technique:
  1. Enter skin, pass through to opposite side, exit.
  2. Re-enter skin 5-8mm along the wound edge on the same side, pass back across, exit.
  3. Tie, creating a "U" shape.
• Caution: High risk of tissue strangulation and suture marks. Use only when necessary. Not typically used on face except scalp.

5. The Corner Stitch (Half-Buried Horizontal Mattress / Tip Stitch)

• Goal: To close a V-shaped flap tip without strangulating the blood supply.
• Indication: Flaps, stellate lacerations with triangular flaps.
• Technique:
  1. Use absorbable or non-absorbable fine suture (5-0 or 6-0).
  2. Enter the skin of the non-flap side (stable tissue), 2-3mm from edge.
  3. Pass horizontally through the dermis of the flap tip (buried bite, intradermal).
  4. Exit skin on the opposite non-flap side.
  5. Tie the knot on one of the stable sides (not on the flap tip).
• Result: Pulls the flap tip into position without a knot sitting directly on the fragile, tenuous blood supply of the apex.
• Alternative Name: "Three-Point Stitch" or "Tip Stitch."

6. The Running (Continuous) Subcuticular Suture

• Goal: Excellent cosmetic outcome with no skin punctures or suture marks.
• Indication: Linear lacerations of face in cooperative patients.
• Technique:
  1. Use absorbable monofilament (5-0 Monocryl) or non-absorbable (5-0 Prolene).
  2. Start at one end, anchor with buried knot or small skin bite.
  3. Pass needle intradermally (within the dermis) in small horizontal bites, alternating sides, progressing along the wound.
  4. End with buried knot or skin exit and tape anchor.
• Advantage: No suture marks (no skin penetration), excellent cosmesis.
• Disadvantage: Technically more demanding, less precise edge control, entire suture line fails if knot loosens. Not suitable for irregular/stellate wounds.
• Removal (if non-absorbable used): Pull one end gently. If absorbable used, no removal needed.

7.5 Tissue Adhesives (Dermabond, Histoacryl)

Cyanoacrylate-based tissue adhesives are an excellent alternative to sutures for selected facial lacerations. [11]

• Indications:
  • Linear lacerations less than 5cm
  • Low-tension wounds
  • Pediatric facial lacerations (avoids suture removal trauma)
  • Scalp lacerations (especially in hair-bearing areas)
• Contraindications:
  • Stellate or irregular wounds
  • Wounds under tension
  • Mucosal surfaces (adhesive will not adhere to wet surface)
  • Hair-bearing areas where hair will be glued (must part hair away from wound edges)
  • Infected or heavily contaminated wounds
  • Joint areas (adhesive cracks with movement)
• Technique:
  1. Ensure complete hemostasis. Dry wound edges thoroughly.
  2. Manually approximate wound edges with fingers or forceps.
  3. Apply thin layer of adhesive over the wound, extending 5-10mm beyond edges on each side.
  4. Hold edges together for 30-60 seconds while adhesive polymerizes.
  5. Apply 2-3 additional layers.
  6. Do NOT apply adhesive into the wound (only on approximated surface).
• Outcomes: Studies show equivalent cosmetic outcomes to sutures for appropriate wounds. [11]
• Advantages: Faster application, painless, no removal required, waterproof, acts as own dressing.
• Disadvantages: Cannot be used for complex/irregular wounds, risk of dehiscence if applied under tension.
• Sloughs Naturally: In 7-10 days.

7.6 Staples

• Indications: Scalp lacerations (NOT face).
• Advantages: Rapid deployment, cost-effective, adequate for hair-bearing scalp.
• Disadvantages: Poor cosmesis (leave marks), painful to remove, not suitable for visible areas.
• Technique: Approximate edges with fingers, apply stapler perpendicular to skin, deploy. Space 0.5-1cm apart.
• Removal: 7-10 days for scalp.

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8. Delayed Primary Closure (DPC)

Definition: Wound closure performed 3-5 days after initial injury, after observation period for infection but before granulation tissue forms.

8.1 Indications for Delayed Primary Closure [12]

1. Contaminated Wounds: Heavy soil, fecal matter, organic contamination.
2. Animal Bites (Selective): High-risk bites (hand, foot, puncture wounds) or presentation > 12-24 hours.
3. Devitalized Tissue: Crush injuries with questionable tissue viability.
4. Delayed Presentation: Clean wounds presenting 12-24+ hours post-injury (individualize decision).
5. High Infection Risk Patients: Poorly controlled diabetes, significant immunosuppression, vascular insufficiency.

8.2 Technique

1. Initial Management (Day 0):
   • Copious irrigation and debridement.
   • Explore for foreign bodies and structural injuries.
   • Leave wound open (do NOT close).
   • Pack loosely with saline-moistened gauze.
   • Apply bulky dressing.
   • Antibiotics if indicated.
2. Observation Period (Days 1-4):
   • Daily dressing changes.
   • Inspect for signs of infection (erythema, purulence, fever).
   • Keep wound moist (prevents desiccation of wound bed).
3. Closure (Days 3-5):
   • If wound appears clean (pink granulation, no purulence), proceed with closure.
   • Refresh edges minimally if needed (light debridement of superficial fibrin).
   • Close in layers as for primary closure.
4. If Infection Develops: Continue open wound management, consider secondary intention healing or later secondary closure.

8.3 Outcomes

• Delayed primary closure has significantly lower infection rates than immediate closure of high-risk wounds (2-5% vs 10-20%). [12]
• Cosmetic outcomes are excellent if performed within 5 days (before significant granulation/contracture).
• Special Consideration for Face: The excellent vascularity of the face allows more permissive approach. Many contaminated facial wounds can be safely closed primarily after thorough irrigation and debridement. DPC is used more selectively on face than on body. [12]

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9. Specific Anatomical Repair Guides

9.1 The Lip (Vermilion Border)

Critical Anatomy: The "White Roll" is the ridge of pale skin just above the red lip (vermilion). It reflects light and is a critical aesthetic landmark. Even 1mm of misalignment breaks this reflection and is highly visible from conversational distance.

Step-by-Step Repair:

1. Nerve Block: Mental nerve block (bilateral if midline). Avoid infiltration which distorts the vermilion border.
2. Mark the Border: Before any injection (if possible) or immediately after injury, use a surgical skin marker or needle dipped in methylene blue to mark the vermilion border on both sides of the laceration. These marks are your registration points.
3. The Key Stitch (First Stitch):
   • Use 6-0 Nylon.
   • Enter exactly at the marked vermilion border on one side.
   • Exit exactly at the marked border on the other side.
   • Tie loosely first to check alignment under good lighting.
   • If misaligned by > 0.5mm, remove and replace. This stitch dictates all subsequent cosmesis.
4. Orbicularis Oris Muscle Repair (Deep Layer):
   • If the muscle is transected (full-thickness or deep laceration), it must be repaired.
   • Use 5-0 Vicryl.
   • Place interrupted sutures through muscle to re-approximate.
   • Failure to repair muscle leads to divot, notch, or whistling deformity.
5. Mucosal Layer (for through-and-through lacerations):
   • Close the wet mucosa (inside of lip) first.
   • Use 5-0 Vicryl Rapide (absorbs quickly, comfortable).
   • Simple interrupted or running suture.
6. Skin (Cutaneous Lip):
   • After muscle and mucosa repaired, close skin.
   • Use 6-0 Nylon, simple interrupted.
   • Align vermilion border stitch first, then work superior and inferior from that anchor point.
7. Vermilion (Red Lip):
   • Close with 6-0 Nylon, simple interrupted.
   • Align carefully to avoid step-off.
8. Suture Removal: 5 days (strict). Lip heals rapidly and sutures cause marks if left longer.

9.2 The Eyelid

Anatomy: Skin → Orbicularis Oculi → Orbital Septum → Tarsal Plate (upper and lower lids) → Conjunctiva. Critical Structures: Levator palpebrae superioris (upper lid elevation), tarsal plate (structural support), lid margin (grey line).

Referral Red Flags (Refer to Ophthalmology or Oculoplastics):

• Lid Margin Laceration: Involves grey line (mucocutaneous junction). Requires precise 3-layer repair to prevent notching.
• Ptosis: Suggests levator aponeurosis injury (upper lid).
• Fat Herniation: Yellow fat prolapsing through wound indicates orbital septum breach → potential orbital injury, requires CT and ophthalmology assessment.
• Medial Canthal Laceration: Risk of lacrimal canaliculus injury (requires microsurgical repair with stent).
• Deep Lacerations: Any laceration deeper than orbicularis muscle.
• Tarsal Plate Involvement: Requires specialized layered repair.

ED Management (Simple Eyelid Skin Lacerations Only):

• Indications for ED Repair: Superficial skin-only lacerations, parallel to lid crease, no lid margin involvement, no ptosis, no fat herniation.
• Anaesthesia: Infraorbital block (lower lid) or supraorbital/supratrochlear block (upper lid). Avoid direct infiltration (distorts delicate anatomy).
• Sutures: 6-0 Prolene (blue color, easy to see and remove, low reactivity).
• Technique: Simple interrupted, perpendicular to lid crease (heals invisibly if parallel to natural crease).
• Suture Removal: 3-4 days (critical). Eyelid skin is thinnest on body and heals rapidly. Sutures left > 4 days cause milia (keratin cysts) and permanent marks.
• Follow-up: Ophthalmology review if any concern about vision, eye movement, or lid function.

9.3 The Ear (Pinna)

Anatomy: Skin is tightly adherent to underlying elastic cartilage on the anterior (lateral) surface. Loose skin with potential space on the posterior (medial) surface. No subcutaneous fat. Perichondrium (cartilage covering) is vascular and critical for cartilage nutrition.

The "Cover the Cartilage" Mandate:

• Exposed cartilage (without perichondrial or skin coverage) is at high risk for Pseudomonas aeruginosa infection (chondritis), which liquefies the ear scaffold and results in "cauliflower ear" deformity.
• Technique: If skin is avulsed, undermine the surrounding skin to create laxity and advance it over the cartilage. Accept skin tension rather than leave cartilage exposed.

Cartilage Repair:

• Principle: Restore anatomical alignment of cartilage to maintain ear shape.
• Technique:
  • Avoid placing sutures through full-thickness cartilage if possible (creates inflammation, chondritis risk).
  • Ideally, place fine absorbable sutures (5-0 or 6-0 Vicryl) through the perichondrium only (the fibrous covering of cartilage) to align cartilage edges.
  • If full-thickness bites necessary, use minimal number of sutures, absorbable material.
  • Do NOT use non-absorbable sutures in cartilage (permanent foreign body, infection risk).
• Irregular Fractures: May require multiple sutures to restore complex 3D anatomy of ear cartilage.

Skin Closure:

• Use 5-0 or 6-0 Nylon, simple interrupted.
• Anterior (lateral) surface: Skin is tight, little redundancy.
• Posterior (medial) surface: More laxity, easier to close.

Hematoma Prevention (Critical):

• Why: Hematoma between skin and cartilage strips the perichondrium from cartilage, causing cartilage necrosis and deformity.
• Dressing: Pressure dressing is MANDATORY.
  • Place non-adherent gauze over wound.
  • Pack gauze behind the ear (in the post-auricular sulcus).
  • Mold gauze soaked in mineral oil or saline into the concavities of the anterior ear (concha, triangular fossa, scaphoid fossa).
  • Wrap head circumferentially with gauze or elastic bandage to apply even pressure.
  • Leave in place 48-72 hours.
• Follow-up: Remove dressing at 48-72 hours, inspect for hematoma. If present, drain immediately.

Suture Removal: 5-7 days.

Antibiotics: Consider anti-Pseudomonal coverage (ciprofloxacin 500mg BD for 5-7 days) for cartilage-involving injuries or contaminated wounds.

9.4 The Nose

Anatomy: Thick sebaceous skin on the tip (nasal lobule); thin mobile skin on the bridge (dorsum). Underlying bony pyramid (nasal bones, frontal process of maxilla) superiorly, cartilaginous pyramid (upper/lower lateral cartilages, septal cartilage) inferiorly.

Through-and-Through Lacerations (involving nasal skin and nasal lining):

• Referral Threshold: Complex through-and-through lacerations (alar rim, nasal tip with cartilage involvement) should be referred to ENT or plastics if available for optimal cosmetic outcome.
• ED Repair (if undertaken):
  • Layer 1 (Nasal Vestibule/Lining): Close internal lining first with 5-0 Vicryl Rapide, mucosa-to-mucosa, knots on inside.
  • Layer 2 (Cartilage): If alar or lateral nasal cartilage is lacerated, align and suture with 5-0 Vicryl, perichondrium to perichondrium if possible.
  • Layer 3 (Skin): Close skin with 6-0 Nylon, simple interrupted, precise edge alignment.
• Alar Rim Alignment: The free edge of the nostril (alar rim) is a critical aesthetic landmark. Misalignment causes notching. Consider using half-buried horizontal mattress (corner stitch) for rim.

Septal Hematoma (Must Not Miss):

• Mechanism: Blunt nasal trauma causes shearing of blood vessels between septal cartilage and mucoperichondrium.
• Presentation: Boggy, purple/blue, fluctuant swelling of nasal septum (palpate inside nose with nasal speculum). Bilateral in 50% of cases. Nasal obstruction.
• Consequence: Untreated hematoma causes pressure necrosis of septal cartilage (cartilage receives nutrition from perichondrium). Cartilage necrosis leads to saddle nose deformity (loss of nasal bridge support). Abscess formation possible (septal abscess).
• Management:
  • Urgent Drainage: Incise mucoperichondrium, evacuate hematoma.
  • Pack: Bilateral nasal packing for 24-48 hours to prevent re-accumulation.
  • Antibiotics: Prophylactic antibiotics (co-amoxiclav or cephalexin) to prevent abscess.
  • ENT Follow-up: Within 48 hours to reassess for re-accumulation.

Simple Nasal Bridge/Tip Lacerations:

• Anaesthesia: Dorsal nasal block or infraorbital block.
• Closure: 6-0 Nylon, simple interrupted.
• Suture Removal: 5 days.

9.5 The Eyebrow

The Landmark: The eyebrow is a key reference line for facial symmetry and expression. Loss of eyebrow definition is aesthetically devastating.

Technique:

1. Do Not Shave: Never shave the eyebrow. Regrowth is unpredictable (may not regrow fully or may grow in wrong direction). Shaving also removes your alignment landmarks (hair follicles).
2. Anaesthesia: Supraorbital/supratrochlear block.
3. Irrigation: Copious irrigation. Scrub out road grit meticulously to prevent "traumatic tattooing" (permanent blue-grey discoloration from embedded particles).
4. Alignment: Use the hair follicles as "graph paper" to align the edges perfectly. Hair should line up across the laceration.
5. Closure:
   • Deep layer (if deep laceration into frontalis): 5-0 Vicryl.
   • Skin: 5-0 or 6-0 Prolene (blue, visible in dark hair) or Nylon.
   • Leave suture tails long (easier to find for removal in hair).
6. Suture Removal: 5 days.

Hair Growth: Scars in the eyebrow do not grow hair. Expect a thin hairless line at the scar site.

9.6 The Forehead

Anatomy: Skin → Subcutaneous tissue → Frontalis muscle (vertical fibers) → Galea aponeurotica (dense fibrous layer connecting to scalp) → Loose areolar tissue → Periosteum → Bone. RSTL (Relaxed Skin Tension Lines): Horizontal creases (forehead wrinkles). Wounds parallel to RSTL heal best.

Horizontal Wounds (Parallel to RSTL):

• Heal well with minimal scarring.
• Simple layered closure:
  • Deep layer: Galea/frontalis with 4-0 Vicryl if deep.
  • Dermis: 5-0 Vicryl or Monocryl.
  • Skin: 5-0 or 6-0 Nylon.

Vertical Wounds (Perpendicular to RSTL):

• Tendency to gape widely (cutting across muscle fibers and RSTL).
• Require aggressive deep tension-relieving sutures.
• Layered closure:
  • Frontalis muscle: 4-0 Vicryl, interrupted, to re-approximate muscle.
  • Deep dermis: 5-0 Vicryl, multiple buried dermal sutures to take tension.
  • Skin: 5-0 or 6-0 Nylon, may require vertical mattress for eversion if tension remains.

Galeal Laceration (Deep to Bone):

• If laceration extends to bone, the galea aponeurotica (the fibrous layer) is lacerated.
• Must close galea: Use 4-0 Vicryl, interrupted sutures.
• Why: Galea provides structural support and transmits frontalis muscle pull to eyebrow. Failure to repair leads to:
  • Depressed scar (lacks underlying support).
  • Brow ptosis (loss of brow elevation on affected side).
  • Persistent gaping.

Suture Removal: 5-7 days.

9.7 The Cheek

Anatomy: Thick skin → Rich subcutaneous fat pad (Buccal Fat Pad / Bichat's Pad) → Facial muscles → Buccinator muscle → Oral mucosa. Critical Structures at Risk:

• Facial Nerve (Buccal and Zygomatic branches): Runs within or deep to SMAS, crossing masseter.
• Parotid Duct (Stenson's Duct): Crosses masseter in middle third of cheek, enters oral cavity opposite upper 2nd molar.

Assessment:

• Facial Nerve: Test smile, eye closure, cheek puffing before anaesthesia.
• Parotid Duct: If laceration crosses danger zone (tragus to mid-philtrum line), test for duct injury:
  • Dry the wound.
  • Massage parotid gland (in front of ear).
  • Look for clear saliva leaking into wound.
  • Alternatively, cannulate intraoral papilla (opposite upper 2nd molar) and inject saline/methylene blue to see if it leaks from wound.
• Through-and-Through: If laceration extends to oral cavity, examine intraorally for mucosal injury.

Management:

• Nerve Injury: If buccal or zygomatic branch transection suspected (facial weakness), refer to plastics/facial nerve surgery. Primary repair required within 72 hours (ideally within 24 hours) for optimal outcomes. [4]
• Parotid Duct Injury: Refer to ENT or plastics. Requires microsurgical repair over stent or duct ligation.
• Simple Cheek Laceration (No structural injury):
  • Layered closure:
    • Deep layer (SMAS/fat): 4-0 or 5-0 Vicryl to obliterate dead space (critical to prevent hematoma).
    • Dermis: 5-0 Vicryl or Monocryl.
    • Skin: 6-0 Nylon.
  • Obliterate Dead Space: The thick subcutaneous fat of the cheek creates large potential space. Unclosed dead space leads to hematoma → infection → abscess → poor scar. Place deep sutures to close this space.
• Through-and-Through:
  • Close oral mucosa first (5-0 Vicryl Rapide, knots on mucosal side).
  • Then close skin layers as above.

Suture Removal: 5 days.

9.8 Scalp

Anatomy: Skin → Subcutaneous tissue → Galea aponeurotica → Loose areolar tissue → Periosteum → Bone. Characteristics: High vascularity (profuse bleeding), high tension, hair-bearing.

Hemostasis:

• Direct pressure.
• Raney clips (scalp clips) applied to wound edges (compress blood vessels in subcutaneous layer).
• Galeal sutures (horizontal mattress with 3-0 Vicryl) compress bleeding vessels.
• Cautery for specific arterial bleeders.

Closure:

• Option 1: Staples (Fastest):
  • Part hair away from wound edges.
  • Approximate edges with fingers or Allis clamps.
  • Apply staples 0.5-1cm apart, perpendicular to wound.
  • Removal: 7-10 days (up to 14 days for posterior scalp under high tension).
• Option 2: Sutures:
  • Galea: 3-0 or 4-0 Vicryl (or PDS for prolonged strength), interrupted or horizontal mattress.
  • Skin: 3-0 or 4-0 Nylon, simple interrupted.
  • Removal: 7-10 days (up to 14 days).
• Option 3: Tissue Adhesive (Dermabond):
  • For linear lacerations less than 5cm, low tension.
  • Part hair away from wound edges (hair will glue together if in contact with adhesive).
  • Manually approximate edges.
  • Apply adhesive over wound (NOT into wound).

Hair Removal: Generally not necessary. Part hair away from wound edges. Only shave if absolutely required for visualization (rare).

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10. Animal Bite Wounds (Special Considerations)

Animal bites, particularly dog bites to the face, present unique challenges due to combined crush, laceration, and puncture injury patterns with polymicrobial contamination.

10.1 Microbiology and Infection Risk [5,13]

Common Pathogens:

• Dog Bites: Pasteurella multocida (50%), Staphylococcus aureus, Streptococcus spp., Capnocytophaga canimorsus (especially dangerous in asplenic or immunocompromised patients), anaerobes.
• Cat Bites: Pasteurella multocida (75-80%, higher than dogs), Bartonella henselae (cat scratch disease).
• Human Bites: Eikenella corrodens, Streptococcus spp., Staphylococcus aureus, anaerobes.

Infection Rates:

High-Risk Factors for Infection:

• Puncture wounds (deep inoculation, difficult to irrigate)
• Crush injuries (tissue devitalization)
• Hand or foot location
• Delayed presentation (> 8-12 hours)
• Inadequate debridement/irrigation
• Cat bites (narrow deep puncture)
• Immunocompromised host
• Diabetes, vascular insufficiency

10.2 Primary Closure vs. Delayed Closure Debate [13,14]

Historical Dogma: "Never close a bite wound" (due to infection risk).

Current Evidence: Primary closure of facial dog bites is safe and yields better cosmetic results, provided rigorous wound preparation performed. [13,14]

Meta-analysis Findings [14]:

• Facial dog bite infection rate with primary closure: 2-5% (similar to non-bite facial lacerations).
• Infection rate with secondary intention healing: Similar or slightly higher.
• Cosmetic outcome: Significantly better with primary closure.
• The rich vascularity of the face provides relative protection against infection.

Current Recommendations:

Criteria for Primary Closure of Facial Dog Bites [13]:

1. Presentation within 12-24 hours.
2. Laceration type (not puncture).
3. Copious high-volume irrigation (≥1 liter).
4. Adequate debridement of devitalized tissue.
5. No gross contamination.
6. Immunocompetent patient.
7. Antibiotic prophylaxis.
8. Close follow-up arranged (24-48 hours).

10.3 Wound Management Protocol for Facial Dog Bites

1. Irrigation: Massive high-volume irrigation (minimum 1 liter, preferably 2 liters). Use normal saline or tap water under pressure (syringe and splash-guard or commercial system).
2. Debridement: Conservative debridement of clearly devitalized tissue. Preserve as much viable tissue as possible (face tolerates marginal tissue better than body due to vascularity).
3. Exploration: Explore for tooth fragments, foreign material. Palpate for underlying fractures (especially with large dog bites - pit bulls, rottweilers cause crush injuries with high fracture risk).
4. Structural Assessment: Check for nerve injury, parotid duct injury, lacrimal system injury as per standard facial laceration assessment.
5. Closure:
   • If low risk: Primary layered closure as per standard facial laceration technique.
   • Loose Approximation: Some authorities recommend slightly loose suturing (not tight apposition) to allow drainage. Evidence is mixed.
   • If high risk: Leave open, dress with saline-soaked gauze, delayed primary closure at 3-5 days.
6. Antibiotics: Prophylactic antibiotics for all significant bite wounds [5,13]:
   • First-line: Co-amoxiclav (Augmentin) 625mg PO TDS for 5-7 days.
     • Covers Pasteurella, Staphylococcus, Streptococcus, anaerobes.
   • Penicillin Allergy:
     • Doxycycline 100mg BD + Metronidazole 400mg TDS, OR
     • Moxifloxacin 400mg OD, OR
     • Clindamycin 300mg QDS + Ciprofloxacin 500mg BD (avoid in children).
   • Duration: 5-7 days for prophylaxis. Extend to 10-14 days if established infection.
7. Tetanus: Update per standard protocol.
8. Rabies: Assess risk (geographic region, animal behavior, vaccination status). If risk present:
   • Post-Exposure Prophylaxis (PEP):
     • Rabies Immunoglobulin (RIG): Infiltrate into and around the wound (as much as anatomically feasible), give remainder IM at distant site.
     • Rabies Vaccine: IM deltoid on Days 0, 3, 7, 14 (and 28 if immunocompromised).
   • Notify public health authorities.
9. Follow-up: Review in 24-48 hours for wound check, earlier if signs of infection develop.

10.4 Breed-Specific Injury Patterns (Medicolegal Awareness)

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11. Scar Minimization and Optimization [15,16]

Scar formation is inevitable with any wound penetrating the dermis. The goal is a fine, flat, pale scar aligned with relaxed skin tension lines (RSTL).

11.1 Factors Affecting Scar Quality

Modifiable Factors (Under clinician control):

• Tension: Most important. Tension-free skin closure (achieved via deep dermal sutures) minimizes scar width.
• Edge Eversion: Slightly everted edges flatten to fine line. Inverted edges create depressed scar.
• Suture Removal Timing: Early removal (3-5 days on face) minimizes suture track marks ("railroad tracks").
• Wound Orientation: Incisions parallel to RSTL heal with minimal visibility. Perpendicular incisions gape and scar more.
• Infection Prevention: Infection dramatically increases scarring.
• Foreign Bodies: Retained foreign material causes chronic inflammation and poor healing.

Non-Modifiable Factors (Patient-dependent):

• Age: Younger patients have more active collagen remodeling (higher risk of hypertrophic scars). Elderly patients have slower healing but often better final scars.
• Genetics: Keloid tendency (more common in African, Asian, Hispanic ancestry).
• Location: High-tension areas (chin, shoulders, sternum) scar worse. High-vascularity areas (face) scar better.
• Skin Type: Fitzpatrick skin types IV-VI at higher risk of dyspigmentation and keloid.

11.2 Evidence-Based Scar Prevention Strategies [15,16]

1. Silicone Gel Sheeting (Level I Evidence) [15]

• Mechanism: Occlusion, hydration of stratum corneum, and regulation of fibroblast activity.
• Evidence: Cochrane review shows silicone sheeting reduces hypertrophic scarring and improves scar appearance. [15]
• Application: Applied continuously (12-24 hours/day) starting when wound epithelialized (approximately 2 weeks post-injury).
• Duration: Minimum 3 months for optimal effect.
• Products: Dermatix, Cica-Care, ScarAway.
• Alternative: Silicone gel (topical) for irregular areas where sheets don't adhere well.

2. Sun Protection (Critical) [16]

• Rationale: Immature scar tissue (first 6-12 months) lacks melanocytes. UV exposure causes permanent hyperpigmentation (scar turns dark brown).
• Protocol: Apply broad-spectrum SPF 50+ sunscreen to scar daily for 12 months.
• Additional: Physical protection (hat, clothing) for first 6 months.
• Evidence: Observational studies show dramatic difference in pigmentation with sun protection vs. no protection. [16]

3. Massage (Scar Mobilization)

• Rationale: Breaks down cross-linked collagen, improves scar pliability.
• Protocol: Begin at 2-3 weeks (once wound fully healed and sutures removed). Massage scar firmly in circular motion for 5 minutes, 2-3 times daily.
• Duration: 3-6 months.
• Evidence: Limited high-quality evidence, but widely practiced with anecdotal success.

4. Moisturization

• Rationale: Prevents scab formation (scabs increase scarring). Maintains moist wound healing environment.
• Protocol: Apply petroleum jelly (Vaseline) or antibiotic ointment twice daily until re-epithelialized. Then continue with fragrance-free moisturizer.
• Evidence: Moist wound healing reduces scar formation compared to dry healing. [16]

5. Early Suture Removal (Face)

• Rationale: Sutures induce local inflammation and track marks if left beyond 5-7 days on face.
• Protocol: Remove facial sutures at 3-5 days (eyelids 3-4 days, face/lip 5 days). Support wound with Steri-Strips for additional 5-7 days after suture removal.
• Evidence: Clinical experience; facial skin heals rapidly and prolonged sutures worsen scarring.

6. Steri-Strips (Tape Reinforcement)

• Rationale: After early suture removal, wound has only ~5-10% of final tensile strength. Tape provides mechanical support during maturation phase.
• Protocol: Apply Steri-Strips immediately after suture removal. Leave in place 5-7 days or until they fall off naturally.
• Evidence: Reduces tension on healing wound, may reduce scar width.

11.3 Advanced Scar Treatment (for Established Scars)

If scar becomes hypertrophic, widened, or pigmented:

1. Intralesional Corticosteroid Injection

• Indication: Hypertrophic scars, keloids.
• Protocol: Triamcinolone 10-40mg/ml injected into scar. Repeat every 4-6 weeks.
• Effect: Reduces inflammation, collagen synthesis, and scar bulk.
• Side Effects: Hypopigmentation, skin atrophy, telangiectasia.

2. Laser Therapy

• Pulsed Dye Laser (PDL):
  • Indication: Red, hypertrophic scars.
  • Mechanism: Targets hemoglobin in scar vasculature, reduces redness and thickness.
  • Timing: Can start as early as 2-3 weeks post-injury (early intervention may prevent hypertrophic scar formation).
• Fractional CO2 Laser:
  • Indication: Mature scars with surface irregularity, pitting, or texture issues.
  • Mechanism: Ablative resurfacing stimulates collagen remodeling.
  • Timing: Typically 6-12 months after injury (once scar matured).

3. Surgical Scar Revision

• Indication: Wide scars, trapdoor deformities, scars crossing RSTL unfavorably.
• Techniques: Elliptical excision and re-closure, Z-plasty (changes scar direction), W-plasty (breaks up linear scar into zigzag).
• Timing: Wait 12 months for scar maturation before revision (scar continues to improve for 12-18 months).

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12. Complications and Management

12.1 Infection [2,5]

Incidence:

• Clean facial lacerations: 1-2%
• Contaminated facial lacerations: 5-8%
• Dog bites (face): 2-5%
• Dog bites (hand): 20-30%

Presentation:

• Erythema extending > 1cm from wound edge
• Purulent discharge
• Increased pain (beyond expected post-repair discomfort)
• Warmth, swelling, induration
• Fever (suggests systemic spread)
• Lymphangitis (red streaking)
• Regional lymphadenopathy

Management:

1. Remove Sutures: If infection develops, remove skin sutures in area of infection to allow drainage.
2. Culture: Swab for culture and sensitivities (guide antibiotic choice).
3. Antibiotics:
   • Empirical: Co-amoxiclav 625mg TDS or Flucloxacillin 500mg QDS (for presumed Staph/Strep).
   • Bite Wounds: Co-amoxiclav (covers Pasteurella).
   • Adjust: Based on culture results.
4. Drainage: If abscess present, incise and drain.
5. Wound Care: Daily dressing changes, saline irrigation.
6. Imaging: If deep infection suspected (facial cellulitis, orbital cellulitis, necrotizing fasciitis), obtain CT to assess extent and rule out abscess.
7. Admission: Consider for:
   • Systemic toxicity (fever, tachycardia, hypotension)
   • Periorbital cellulitis (risk of orbital/intracranial spread)
   • Rapidly spreading cellulitis
   • Immunocompromised patients
   • IV antibiotics required

12.2 Hematoma

Risk Factors: Anticoagulation (warfarin, DOACs, aspirin/clopidogrel), bleeding disorders, inadequate hemostasis, dead space not obliterated.

Presentation: Expanding swelling, fluctuance, ecchymosis, tension on suture line.

Management:

1. Small Hematoma (less than 1-2cm, stable): Observe. May resorb.
2. Large or Expanding Hematoma:
   • Remove sutures over hematoma.
   • Evacuate clot manually or with irrigation.
   • Identify and control bleeding source (pressure, cautery, ligation).
   • Re-close in layers, ensuring dead space obliterated with deep sutures.
   • Consider pressure dressing.
3. Prevention:
   • Meticulous hemostasis before closure.
   • Obliterate dead space with deep sutures.
   • Pressure dressing for high-risk patients (anticoagulated, ear lacerations).

12.3 Dehiscence (Wound Breakdown)

Causes: Premature suture removal, infection, excessive tension, poor deep layer closure, patient non-compliance (trauma to wound).

Management:

1. Early Dehiscence (less than 48 hours): Re-approximate and re-suture if wound clean.
2. Late Dehiscence (> 48-72 hours): If wound clean, can attempt Steri-Strip closure or tissue adhesive. If contaminated, leave open and heal by secondary intention or delayed secondary closure.
3. Prevention: Adequate deep layer closure to bear tension, patient education (avoid manipulation, trauma to wound).

12.4 Nerve Injury

Facial Nerve (CN VII):

• Presentation: Weakness or paralysis in distribution of injured branch (see Section 3.3 for branch functions).
• Assessment: Distinguish transection (complete loss of function) from neuropraxia (bruising, temporary dysfunction).
• Management:
  • If identified at initial presentation: Refer to plastics/ENT/facial nerve surgeon for primary repair. Optimal outcomes with repair within 72 hours. [4]
  • Microsurgical Repair: End-to-end neurorrhaphy under microscope or loupe magnification with 9-0 or 10-0 nylon sutures.
  • Delayed Recognition: If nerve injury discovered days later, refer for exploration and possible nerve grafting (outcomes worse with delayed repair).
• Prognosis: Depends on mechanism, location, timing of repair. Distal branches (bucal, marginal mandibular) have better outcomes than proximal trunk injuries. Expect 6-12 months for recovery even with successful repair.

Sensory Nerve (Trigeminal branches):

• Infraorbital Nerve (V2): Numbness of cheek, upper lip, lower eyelid.
• Mental Nerve (V3): Numbness of chin, lower lip.
• Management: No specific treatment. Counsel patient that sensation usually returns over 3-12 months as nerve regenerates (1mm/day). Some permanent deficit possible with complete transection.

12.5 Parotid Duct Injury

Presentation: Saliva leaking from wound, salivary fistula, sialocele (salivary cyst).

Management:

• Refer to ENT or Plastics for microsurgical repair over stent (cannulate duct, pass stent, repair duct over stent with 8-0 or 9-0 suture under microscope).
• Alternative (if distal injury or repair not feasible): Duct ligation at site of injury. Gland will atrophy over time. May cause temporary swelling.
• If Missed Initially: Salivary fistula may close spontaneously with conservative management (pressure dressing, anticholinergic to reduce saliva production). If persistent, requires delayed surgical repair.

12.6 Lacrimal System Injury

Presentation: Tearing (epiphora), medial canthal laceration.

Management: Refer to ophthalmology/oculoplastics for canalicular repair with stent placement (requires microscope or loupe magnification, specialized Crawford stent).

12.7 Hypertrophic Scar and Keloid

Hypertrophic Scar: Raised scar confined to original wound boundaries. Keloid: Scar extending beyond original wound boundaries, does not regress.

Risk Factors: Genetic predisposition (Fitzpatrick skin types IV-VI), young age, high-tension areas, infection, delayed healing.

Prevention: As per Section 11.2.

Treatment: As per Section 11.3 (intralesional steroids, laser, scar revision).

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13. Antibiotic Prophylaxis Strategy [5,13]

The routine use of antibiotics for non-bite facial lacerations is not supported by evidence and contributes to antimicrobial resistance. Infection rate of clean facial lacerations is less than 2% regardless of prophylaxis. [5]

13.1 Indications for Prophylaxis

Antibiotic prophylaxis recommended for:

1. Bite Wounds (All significant bites):

   • Dog/Cat/Human: Polymicrobial contamination.
   • Drug: Co-amoxiclav 625mg PO TDS for 5-7 days (covers Pasteurella, Staphylococcus, Streptococcus, anaerobes).
   • Penicillin Allergy: Doxycycline 100mg BD + Metronidazole 400mg TDS, OR Moxifloxacin 400mg OD.

2. Cartilage Involvement (Ear, Nose):

   • Risk: Pseudomonas aeruginosa chondritis.
   • Drug: Ciprofloxacin 500mg BD for 5-7 days (adults), OR Co-amoxiclav if Pseudomonas risk lower.

3. Through-and-Through Oral Cavity (Lip, Cheek):

   • Risk: Oral flora contamination.
   • Drug: Penicillin V 500mg QDS or Amoxicillin 500mg TDS for 5 days, OR Co-amoxiclav if broader coverage desired.

4. Host Risk Factors:

   • Diabetes: Particularly if poorly controlled (HbA1c > 8%), impaired microcirculation and immune function.
   • Immunosuppression: Steroids (> 20mg prednisone daily or equivalent), chemotherapy, biologics (anti-TNF, etc.), HIV (CD4 less than 200).
   • Vascular Insufficiency: Peripheral vascular disease, venous stasis.
   • Valvular Heart Disease: For intraoral wounds, consider endocarditis prophylaxis per guidelines (Amoxicillin 2g PO single dose 1 hour pre-procedure if high-risk cardiac lesion).

5. Wound Factors:

   • Heavy Contamination: Soil, fecal matter, organic debris despite irrigation.
   • Devitalized Tissue: Extensive crush injury despite debridement.
   • Delayed Presentation: > 12-24 hours for non-bite wounds (individualize).

13.2 Tetanus Prophylaxis

*Tetanus-prone wounds: Puncture, crush, contaminated with soil/manure, devitalized tissue, > 6 hours old, bites.

TIG (Tetanus Immunoglobulin): 250 units IM at site separate from vaccine. Td: Tetanus-diphtheria toxoid (adult formulation). Tdap: Tetanus-diphtheria-acellular pertussis (preferred if never received Tdap as adult).

13.3 Rabies Prophylaxis

Indications for Post-Exposure Prophylaxis (PEP):

• Unprovoked animal attack (especially dog, cat, bat, fox, raccoon, skunk).
• Wild animal bite (consider rabies endemic unless proven otherwise).
• Animal unavailable for observation or testing.
• Endemic area with rabies circulation.

PEP Protocol (Non-immunized patient):

1. Rabies Immunoglobulin (RIG): 20 IU/kg body weight.
   • Infiltrate as much as anatomically feasible into and around the wound.
   • Give remainder IM at site distant from vaccine (e.g., gluteal region if vaccine given in deltoid).
2. Rabies Vaccine: 1ml IM deltoid on Days 0, 3, 7, 14 (and Day 28 if immunocompromised).

PEP Protocol (Previously immunized patient):

1. No Immunoglobulin (already has antibodies).
2. Rabies Vaccine: 1ml IM deltoid on Days 0 and 3 only.

Contact Public Health: Immediately for all potential rabies exposures (reportable disease, animal quarantine/testing coordination).

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14. Disposition and Follow-Up

14.1 Discharge Instructions

Wound Care:

• Keep wound dry for first 24 hours.
• After 24 hours, gentle washing with soap and water daily. Pat dry.
• Apply thin layer petroleum jelly (Vaseline) or antibiotic ointment (Neosporin) twice daily until sutures removed.
• No scab formation (keep moist).

Activity Restrictions:

• No heavy lifting, straining, or vigorous exercise for 48 hours (increases blood pressure → risk of bleeding/hematoma).
• Avoid contact sports or activities that could re-injure wound until healed.
• No swimming (pool, ocean, bath) until sutures removed and wound fully sealed (approx 2 weeks).

Sun Protection:

• Avoid direct sun exposure to wound.
• Apply SPF 50+ sunscreen daily for 12 months (prevents permanent hyperpigmentation).

Cosmetics:

• No makeup or cosmetics on wound until sutures removed and wound fully re-epithelialized (approx 2 weeks).

Signs of Infection (Return immediately if):

• Spreading redness (> 1cm from wound edge)
• Yellow or green pus
• Increasing pain
• Warmth, swelling
• Fever (> 38°C / 100.4°F)
• Red streaking from wound

14.2 Suture Removal Schedule

Timing is critical: Early removal minimizes suture track marks. Late removal increases scarring.

Post-Removal Support: Apply Steri-Strips for additional 5-7 days after suture removal (wound has only 5-10% of final tensile strength at 1 week).

14.3 Follow-Up

Routine Follow-Up:

• First Visit: Suture removal (timing per table above).
• Wound Check: 24-48 hours for high-risk wounds (bites, contaminated, complex repairs).
• Scar Assessment: 3-6 months (if hypertrophic scar develops, refer for scar management).

Specialist Referral Indications:

• Nerve injury (plastics/ENT/facial nerve surgery)
• Parotid duct injury (ENT/plastics)
• Lacrimal injury (ophthalmology/oculoplastics)
• Eyelid margin laceration (ophthalmology/oculoplastics)
• Complex flaps or tissue loss (plastics)
• Unsatisfactory scar (plastics for scar revision, typically at 12 months)

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15. Documentation and Medicolegal Considerations

Facial lacerations are high-risk for litigation due to cosmetic implications and risk of missed structural injuries.

15.1 Photography

Consent: Obtain verbal (document in notes) or written consent for photography.

Timing:

• Pre-Repair: Before anaesthesia or manipulation. Documents severity, foreign contamination, alignment.
• Post-Repair: After completion. Documents quality of alignment, closure technique.

Purpose:

• Medicolegal protection (patients often forget severity of initial injury and may have unrealistic expectations).
• Quality assurance.
• Teaching.

Technique: Multiple angles, close-up and wide field, good lighting, ruler for scale.

15.2 Procedure Note Template

Comprehensive documentation is your medico-legal shield. Include:

Procedure Note: Repair of Facial Laceration

• Indication: [X]cm laceration to [specific location], [mechanism], [timing]
• Pre-Procedure Assessment:
  • Neurovascular Status:
    • CN VII: [Specific findings: "Patient able to raise eyebrows, close eyes, smile, show teeth, depress lower lip symmetrically."] OR [Document deficit: "Unable to raise right eyebrow - frontal branch injury suspected."
    • CN V: [Sensation intact V1/V2/V3] OR [Describe deficit]
    • Parotid Duct: [Patent - no saliva leak on gland massage] OR [Injury suspected]
    • Lacrimal System: [No medial canthal involvement] OR [Refer ophthalmology]
  • Wound Assessment: [Length, depth, tissue viability, contamination, foreign bodies]
• Consent: Risks discussed: infection (less than 2% for clean facial lacerations), bleeding, hematoma, scarring (may be visible), asymmetry, nerve injury (if concern), need for revision, and anesthetic risks. [Verbal/Written] consent obtained.
• Anaesthesia: [Volume]ml of [Lidocaine 1%/2%] with/without [Epinephrine 1:100,000/1:200,000], [Buffered with sodium bicarbonate]. [Regional block: specify type] OR [Local infiltration].
• Preparation: Wound irrigated with [volume]ml [normal saline/tap water] under [moderate pressure]. [Debrided/no debridement required]. [Foreign body exploration - none found] OR [Foreign body removed: specify]. Surrounding skin prepped with [chlorhexidine/povidone-iodine].
• Repair Technique:
  • Deep Layer: [Number] sutures of [size/type] to [SMAS/muscle/subcutaneous tissue/galea]. Tension-relieving buried dermal sutures placed.
  • Skin Layer: [Number] sutures of [size/type] [simple interrupted/vertical mattress/running subcuticular]. Wound edges approximated with [eversion/no tension].
  • Special Structures: [Vermilion border aligned precisely] OR [Muscle repaired] OR [Cartilage approximated]
• Hemostasis: [Achieved with direct pressure/cautery/ligation].
• Dressing: [Antibiotic ointment applied, Steri-Strips applied, pressure dressing] OR [left open to air].
• Post-Procedure Assessment: Wound edges well-approximated, [no bleeding], [patient tolerated well, no complications].
• Plan:
  • Suture removal: [Day 5] at [GP/outpatient clinic/return to ED]
  • Wound care instructions provided (written sheet given)
  • [Antibiotics prescribed: specify drug, dose, duration, indication] OR [No antibiotics - low-risk wound]
  • [Tetanus booster given] OR [Tetanus status up to date]
  • Return precautions: signs of infection, dehiscence
  • [Follow-up arranged with plastics/ENT/ophthalmology for [nerve injury/duct injury/etc.]]

15.3 Informed Consent

Discuss and Document:

• Infection risk (quote less than 2% for clean facial wounds)
• Scarring (inevitable, goal is fine scar)
• Asymmetry (especially if nerve injury concern)
• Numbness (sensory nerve injury common, usually temporary)
• Need for revision (5-10% may request scar revision at 12 months)
• Anesthetic risks (allergic reaction, LAST - rare)

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16. Special Populations

16.1 Pediatrics

Challenges: Anxiety, inability to cooperate, need for immobility.

Anxiety Management:

• Topical Anesthesia (LET Gel): Apply 30-45 minutes before procedure. Reduces or eliminates need for needle injection.
• Distraction: Age-appropriate (toys, videos, parent involvement).
• Intranasal Midazolam: 0.3-0.5 mg/kg (max 10mg) via mucosal atomizer. Onset 10 minutes, provides anxiolysis and amnesia.
• Ketamine Dissociation: For complex repairs (lip, eyelid). Dose: 1-1.5 mg/kg IV or 3-4 mg/kg IM. Requires monitoring, capnography, airway management capability.

Restraint:

• Papoose board (mummy restraint): Controversial, traumatic, use as last resort.
• Parental holding with assistant support: Preferred if safe.

Suture Material:

• Consider absorbable sutures (Fast-Absorbing Gut or Vicryl Rapide) for skin to avoid traumatic removal.
• Accept slightly inferior cosmesis for avoidance of removal trauma (especially children less than 5 years).

Tissue Adhesive: Excellent option for appropriate wounds (linear, low tension). No removal needed.

Non-Accidental Injury (NAI) Red Flags:

• Delayed presentation (> 24 hours, vague explanation)
• Mechanism inconsistent with injury pattern or developmental stage
• Bruising to ears, neck, cheeks (soft tissues that don't bruise in normal falls)
• Torn frenulum (upper lip) in non-ambulatory infant (forced bottle feeding)
• Multiple injuries of different ages
• Reluctance to explain mechanism

Action if NAI Suspected: Document thoroughly (body map, photographs), consult pediatrics and social work, follow local safeguarding protocols.

16.2 Geriatrics

Challenges: Thin, fragile skin; anticoagulation; comorbidities.

Thin Skin ("Tissue Paper" Skin):

• Problem: Sutures cut through skin (cheese-wire effect).
• Solutions:
  • Steri-Strips: Often superior to sutures for linear tears in elderly. Apply in ladder pattern across wound.
  • Tissue Adhesive: Good option for linear lacerations.
  • Wider Bites: If suturing, take larger bites (4-5mm from edge instead of 2-3mm) to distribute tension.
  • Larger Suture Size: Paradoxically, 4-0 or 5-0 Nylon (instead of 6-0) cuts through less, but leaves more marks. Balance required.
  • Minimal Tension: Avoid any tension on skin. Deep layer closure critical.

Anticoagulation Management:

• Warfarin: Check INR.
  • If INR less than 3.0: Proceed with repair. Achieve meticulous hemostasis.
  • If INR 3-5: Proceed, expect more oozing. Consider pressure dressing.
  • If INR > 5: Discuss with hematology/patient's physician regarding reversal vs. proceeding.
• DOACs (Apixaban, Rivaroxaban, Dabigatran, Edoxaban): No INR to check. Rely on mechanical hemostasis (pressure, cautery, suture ligation). Time since last dose relevant (peak effect 2-4 hours after dose).
• Antiplatelet (Aspirin, Clopidogrel): Increased bleeding but rarely prohibitive. Achieve hemostasis before closure.
• Pressure Dressing: Apply for 24 hours in anticoagulated patients to prevent hematoma.
• Tranexamic Acid: Consider topical application (500mg in 5ml soaked gauze applied to wound for 5 minutes) or IV dose (1g IV over 10 min) if bleeding difficult to control.

Comorbidities:

• Diabetes: Higher infection risk. Consider lower threshold for antibiotics. Optimize glucose control.
• Immunosuppression: Higher infection risk, slower healing.

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17. Common Mistakes and Pitfalls

❌ Mistakes that fail candidates (exams) or harm patients (clinical practice):

1. Injecting local anaesthetic BEFORE testing facial nerve function: Once numb, you cannot distinguish true nerve injury from iatrogenic paralysis. Medicolegally indefensible.

2. Infiltrating directly into wound edges (especially lip vermilion): Distorts anatomy and makes precise alignment impossible. Use nerve blocks instead.

3. Missing parotid duct injury in cheek lacerations: Always test for duct integrity (massage gland, look for saliva leak). Missed injury leads to salivary fistula.

4. Closing skin under tension: Recipe for wide scar. Must place deep dermal/SMAS sutures to bear all tension.

5. Leaving sutures in face > 5-7 days: Causes permanent suture track marks ("railroad tracks").

6. Not checking inside the nose for septal hematoma: Missed septal hematoma causes saddle nose deformity. Check every nasal trauma.

7. Shaving the eyebrow: Removes alignment landmarks and hair may not regrow. Never shave eyebrows.

8. Closing bite wounds to hand or foot primarily: High infection risk. Leave open or delayed primary closure.

9. Missing retained foreign bodies (glass, teeth): X-ray all glass injuries, check for tooth fragments in lip/knuckle lacerations.

10. Inadequate irrigation: "The solution to pollution is dilution." Minimum 200ml per cm of laceration.

11. Not documenting pre-procedure neurovascular exam: Medicolegally essential. Must document specific functional testing, not just "CN VII intact."

12. Misaligning vermilion border by > 1mm: Visible from conversation distance. Take time to get first stitch perfect.

13. Using tissue adhesive on wounds under tension: Will dehisce. Glue only works for low-tension approximated wounds.

14. Failing to obliterate dead space (especially cheek): Leads to hematoma → infection → abscess.

15. Not providing sun protection instructions: UV exposure causes permanent scar hyperpigmentation. Must counsel on SPF 50+ for 12 months.

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18. Clinical Pearls (High-Yield Tips)

1. "The Solution to Pollution is Dilution": High-volume irrigation is the single most important infection prevention measure. Use minimum 1 liter for facial wounds.

2. "Evert, Don't Invert": Wound edges should pout slightly outward. Inverted edges create depressed scar. Use vertical mattress if needed.

3. "Buffer your Lidocaine": 1ml Bicarb (8.4%) + 9ml Lidocaine. Reduces injection pain by > 50%.

4. "Respect the Vermilion": Take 5 minutes to place first stitch at vermilion border perfectly. If > 0.5mm off, remove and replace. This stitch determines entire cosmetic outcome.

5. "Don't Shave the Brow": Removes your alignment landmarks (hair follicles) and hair may not regrow.

6. "Glue the Kids": For forehead laceration in anxious child, LAT gel + Dermabond gives excellent result without wrestling with needle and sutures.

7. "The Golden Period for Face": Facial wounds can be closed up to 24 hours (sometimes longer) due to excellent vascularity. If tired/uncertain/middle of night, clean, dress, defer to specialist in morning.

8. "Check the Septum Every Time": Every nasal trauma requires speculum exam to rule out septal hematoma. Surgical emergency.

9. "Fight Bite = Fist-to-Tooth": Laceration over MCP joint is human bite until proven otherwise. Do not close. High infection risk (50%), risk of septic arthritis.

10. "Tape Support After Early Removal": Remove facial sutures at day 5, then apply Steri-Strips for additional 5-7 days. Wound has only 5% tensile strength at 1 week.

11. "Two Layers Minimum": All facial lacerations deeper than superficial dermis require layered closure (deep + skin). Skin-only closure under tension = wide scar.

12. "Epinephrine is Safe in Digits and Nose": Historical teaching is wrong. Epinephrine in fingers/toes/nose is safe and dramatically improves hemostasis. [6]

13. "Early Suture Removal = Better Scar": Face 5 days, eyelids 3-4 days. Mark on calendar. Don't let patient delay.

14. "Sun is the Enemy of New Scars": UV causes permanent hyperpigmentation of immature scar. SPF 50+ daily for 12 months non-negotiable.

15. "Photograph Everything": Pre- and post-repair photos protect you medico-legally and align patient expectations.

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19. Examination Focus (MRCS, FRCS)

19.1 Viva Questions (Model Answers)

Q1: "Describe the surface anatomy of the Parotid Duct."

• A: "The parotid duct, or Stenson's duct, runs along a line drawn from the tragus to the mid-philtrum. It crosses the masseter muscle in the middle third of the cheek, approximately 1-1.5cm below the zygomatic arch. It pierces the buccinator muscle and opens into the oral cavity via a papilla opposite the upper second molar. The duct is approximately 5-7cm long and 3-4mm in diameter. The buccal branch of the facial nerve runs parallel and superficial to the duct in this region."

Q2: "What are the indications for antibiotic prophylaxis in facial lacerations?"

• A: "Routine antibiotic prophylaxis is NOT indicated for clean facial lacerations, which have an infection rate below 2%. Prophylaxis is indicated for: (1) All significant bite wounds - I would use co-amoxiclav to cover Pasteurella, Staphylococcus, and anaerobes; (2) Cartilage involvement - such as ear or nose lacerations, where I would use ciprofloxacin for Pseudomonas coverage; (3) Through-and-through oral cavity wounds to cover oral flora; and (4) Host risk factors such as diabetes, immunosuppression, or valvular heart disease."

Q3: "How would you assess for facial nerve injury in a cheek laceration?"

• A: "Facial nerve assessment must be performed BEFORE infiltrating local anaesthetic. I would systematically test all five branches: (1) Temporal branch - ask patient to raise eyebrows; (2) Zygomatic branch - ask to close eyes tightly; (3) Buccal branch - ask to puff out cheeks and show teeth; (4) Marginal mandibular branch - ask to depress lower lip and show bottom teeth; and (5) Cervical branch - ask to tense the neck. I would document specific findings rather than generic statements. If weakness identified, I would refer urgently to plastics or ENT for microsurgical nerve repair within 72 hours."

Q4: "What is the maximum dose of Lidocaine with Epinephrine, and what are the signs of toxicity?"

• A: "The maximum dose of lidocaine with epinephrine is 7 mg/kg, compared to 3 mg/kg for plain lidocaine. For a 70kg patient, this is approximately 490mg, or 49ml of 1% lidocaine. Signs of Local Anaesthetic Systemic Toxicity (LAST) progress from CNS excitation - perioral tingling, metallic taste, and tinnitus - to CNS depression - confusion, slurred speech, drowsiness - and finally cardiovascular collapse with seizures and cardiac arrest. Management includes stopping the injection, 100% oxygen, benzodiazepines for seizures, and lipid rescue therapy with 20% Intralipid at 1.5ml/kg bolus followed by infusion."

Q5: "Describe your technique for achieving tension-free skin closure."

• A: "Tension-free closure is achieved through the deep dermal or buried vertical mattress suture. Using absorbable suture such as 4-0 or 5-0 Vicryl, I enter at the base of the dermis on one side, pass through to exit just below the skin surface, cross to the opposite side, enter superficially and exit deep, then tie the knot at the base. This buries the knot and pulls the deep tissues together, eliminating tension on the skin. The skin edges should spontaneously approximate or 'kiss' without any tension. The skin sutures then simply align the edges precisely rather than bearing tension. This allows early suture removal at 3-5 days without dehiscence risk and minimizes scar width."

Q6: "When would you consider delayed primary closure for a facial laceration?"

• A: "Delayed primary closure involves closing the wound at 3-5 days after initial presentation, after monitoring for infection but before granulation tissue forms. I would consider this for: (1) Heavily contaminated wounds despite thorough irrigation; (2) High-risk animal bites such as hand punctures or presentation beyond 12 hours; (3) Crush injuries with questionable tissue viability; and (4) High-risk patients such as those with poorly controlled diabetes. The facial blood supply is so robust that many contaminated facial wounds can be safely closed primarily after copious irrigation, so I use delayed closure more selectively on the face than on the body. The technique involves initial thorough irrigation and debridement, leaving the wound open with moist dressing, daily wound checks, and formal closure at 3-5 days if no infection develops."

Q7: "What is your suture removal schedule for facial wounds and why?"

• A: "Suture removal timing is critical for minimizing scarring. Eyelids at 3-4 days - the skin is thinnest and heals fastest, and sutures left beyond 4 days cause milia formation. Face, lip, nose, and eyebrow at 5 days - this is strict, as facial skin heals rapidly and sutures cause permanent track marks if left longer. Ear at 5-7 days. Forehead at 5-7 days. Scalp at 7-10 days, up to 14 days for posterior scalp under high tension. After suture removal, I apply Steri-Strips for an additional 5-7 days because the wound has only 5-10% of its final tensile strength at one week."

19.2 OSCE Station Checklist

Scenario: "Repair this mannequin's lip laceration crossing the vermilion border."

Examiner Checklist (Passing requires all critical items):

• CRITICAL: Checks neurovascular status BEFORE injecting anaesthetic (facial nerve motor, sensation)
• Verbalizes plan for mental nerve block (avoids infiltration that distorts vermilion)
• CRITICAL: Identifies and marks the vermilion border on both sides of laceration
• Discusses need for layered closure (orbicularis oris muscle, skin, vermilion)
• CRITICAL: Places first stitch exactly at the vermilion border as registration point
• Checks alignment of vermilion border stitch before proceeding
• Demonstrates appropriate suture material selection (6-0 Nylon for skin, 5-0 Vicryl for muscle)
• Discusses deep muscle repair if full-thickness
• Demonstrates proper suture technique (perpendicular needle entry, eversion of edges)
• Provides accurate discharge advice (suture removal day 5, sun protection, wound care)
• Documents "No foreign body, no nerve injury" in procedure note
• Discusses complications (infection less than 2%, scarring inevitable, potential need for revision)

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20. Key Guidelines and Evidence Base

20.1 Major Society Guidelines

1. British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS): Standards for management of facial soft tissue injuries
2. American College of Emergency Physicians (ACEP): Clinical policy on wound management
3. European Society of Emergency Medicine: Traumatic wound management guidelines

20.2 Landmark Studies (High-Yield for Exams)

• Hollander et al. (1999): Established that clean facial lacerations have less than 2% infection rate regardless of antibiotic prophylaxis. Antibiotic overuse not justified. [5]
• Quinn et al. (1998): Tissue adhesive (Dermabond) produces equivalent cosmetic outcomes to sutures for appropriate facial lacerations. [11]
• Moscati et al. (2007): Tap water irrigation equivalent to normal saline for wound cleaning. Cost-effective and safe. [8]
• Lakstein et al. (2017): Primary closure of facial dog bites safe with infection rate 2-5%, significantly better cosmesis than secondary intention. [14]

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21. References

1. Hollander JE, Singer AJ, Valentine S, Henry MC. Wound registry: development and validation. Ann Emerg Med. 1995;25(5):675-85. doi:10.1016/s0196-0644(95)70183-4

2. Berk WA, Osbourne DD, Taylor DD. Evaluation of the 'golden period' for wound repair: 204 cases from a Third World emergency department. Ann Emerg Med. 1988;17(5):496-500. doi:10.1016/s0196-0644(88)80242-5

3. Boffano P, Roccia F, Zavattero E, et al. European Maxillofacial Trauma (EURMAT) project: a multicentre and prospective study. J Craniomaxillofac Surg. 2015;43(1):62-70. doi:10.1016/j.jcms.2014.10.011

4. Tzafetta K, Terzis JK. Essays on the facial nerve: Part I. Microanatomy. Plast Reconstr Surg. 2010;125(3):879-89. doi:10.1097/PRS.0b013e3181cb6685

5. Hollander JE, Richman PB, Werblud M, Miller T, Huggler J, Singer AJ. Irrigation in facial and scalp lacerations: does it alter outcome? Ann Emerg Med. 1998;31(1):73-7. doi:10.1016/s0196-0644(98)70284-x

6. Wilhelmi BJ, Blackwell SJ, Miller JH, et al. Do not use epinephrine in digital blocks: myth or truth? Plast Reconstr Surg. 2001;107(2):393-7. doi:10.1097/00006534-200102000-00014

7. Bartfield JM, Gennis P, Barbera J, Breuer B, Gallagher EJ. Buffered versus plain lidocaine as a local anesthetic for simple laceration repair. Ann Emerg Med. 1990;19(12):1387-9. doi:10.1016/s0196-0644(05)82605-6

8. Moscati RM, Mayrose J, Reardon RF, Janicke DM, Jehle DV. A multicenter comparison of tap water versus sterile saline for wound irrigation. Acad Emerg Med. 2007;14(5):404-9. doi:10.1111/j.1553-2712.2007.tb01798.x

9. Orlinsky M, Knittel P, Feit T, Chan L, Mandavia D. The comparative accuracy of radiolucent foreign body detection using ultrasonography. Am J Emerg Med. 2000;18(4):401-3. doi:10.1053/ajem.2000.7302

10. Moy RL, Lee A, Zalka A. Commonly used suturing techniques in skin surgery. Am Fam Physician. 1991;44(5):1625-34. PMID:1950961

11. Quinn JV, Drzewiecki A, Li MM, et al. A randomized, controlled trial comparing a tissue adhesive with suturing in the repair of pediatric facial lacerations. Ann Emerg Med. 1993;22(7):1130-5. doi:10.1016/s0196-0644(05)80978-6

12. Rutherford WH, Spence RA. Infection in wounds sutured in the Accident and Emergency Department. Ann Emerg Med. 1980;9(7):350-2. doi:10.1016/s0196-0644(80)80126-2

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14. Lakstein D, Kedar A, Heller S, Goldberg A, Schindler A. Primary Closure of Dog Bite Injuries Involving the Face: Our Experience and a Review of the Literature. Isr Med Assoc J. 2017;19(4):222-5. PMID:28480679

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22. Summary: Key Takeaways

1. Assessment First: Always check facial nerve and structural integrity BEFORE injecting anaesthetic.

2. Irrigation is King: High-volume irrigation (≥1L) is the most important infection prevention measure.

3. Tension-Free Closure: Use deep dermal sutures to bear all tension. Skin sutures only align edges.

4. Early Suture Removal: Face at 5 days, eyelids at 3-4 days. Prevents suture track marks.

5. Face is Forgiving: The rich vascular supply allows closure up to 24 hours and survival of marginal tissue.

6. Respect Critical Landmarks: Vermilion border, eyelid grey line, eyebrow hairs are "registration points"

• must align perfectly.

7. Antibiotics are Selective: NOT routine. Indicated for bites, cartilage, oral cavity, and high-risk hosts.

8. Primary Closure of Facial Dog Bites: Safe with thorough irrigation, debridement, and antibiotics. Better cosmesis than delayed closure.

9. Nerve Blocks > Infiltration: Regional blocks avoid anatomical distortion and provide superior anaesthesia for complex repairs.

10. Sun Protection for 12 Months: SPF 50+ daily prevents permanent scar hyperpigmentation.

11. Document Meticulously: Comprehensive procedure note with pre-repair neurovascular exam, consent discussion, and photographs protect medicolegally.

12. Know When to Refer: Nerve injuries, parotid duct injuries, lacrimal injuries, eyelid margin lacerations, and complex tissue loss require specialist input.

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Citation Count: 24 Evidence Level: High Target Examination: MRCS, FRCS (Plastics), Emergency Medicine