Simple laceration repair and wound management — formative SAQs

SAQ 1 — Clean facial laceration: assessment, analgesia, closure and aftercare (15 marks, 15 minutes)

A previously well four-year-old falls against a table edge and splits the skin over her chin. The laceration is clean, three centimetres long, superficial, and the edges oppose easily. She is frightened but cooperative with distraction. [1] [8]

Question. Outline your structured assessment, your approach to analgesia, your choice of closure method (with justification), and the aftercare and follow-up you would give the family. Explain your reasoning.

Model answer

Assessment (4 marks). Take a targeted history: mechanism (blunt table edge), time of injury, oral intake, immunisation and tetanus status, allergies, bleeding disorder, previous reaction to anaesthetic or adhesive. Examine in good light: depth, edges (clean and incised), contamination, foreign body, and — for a face wound — assess the lip vermillion border, facial nerve function, and distal sensation and function. Run the MADNESS check (mechanism, age of wound, depth and distal neurovascular, non-accidental-injury, examine tendon and joint, site and tension, safeguarding and tetanus). This wound is clean, superficial, low-tension, and suitable for bedside closure. [1]

Analgesia (3 marks). The default first step is topical LET gel (lidocaine four percent, epinephrine one in two thousand, tetracaine half percent) applied into the wound under an occlusive dressing for twenty to thirty minutes, with distraction and comfort positioning. LET anaesthetises the dermis and makes even subsequent infiltration painless. Avoid LET on mucous membranes. If infiltration is needed, calculate the lidocaine maximum dose first: plain three milligrams per kilogram, with adrenaline seven milligrams per kilogram, bupivacaine two milligrams per kilogram. [4] [10]

Closure method (4 marks). For a clean, low-tension, simple laceration under five centimetres whose edges oppose easily, tissue adhesive (two-octylcyanoacrylate) is first-line: it is fast, painless, needs no removal, and gives equivalent cosmetic outcome to suturing. If sutures were chosen (for example for precise cosmesis), use a 6-0 or 5-0 non-absorbable suture on the face, removed at five days. Avoid tissue adhesive on mucosa, high-tension skin, bites, or infected wounds — none of which apply here. [8]

Irrigation, aftercare and follow-up (4 marks). Irrigate with tap water (as effective as saline in children) at moderate pressure before closure. Give written advice: keep clean and dry for forty-eight hours, do not pick at the glue (which peels off at five to ten days), protect the healing scar from sun, and return with spreading redness, increasing pain, swelling, discharge, or fever. No removal appointment is needed for tissue adhesive. State that the scar fades over twelve to eighteen months and that a child-centred, painless repair protects future relationships with healthcare. [1] [9]

SAQ 2 — Dog bite to the hand: irrigation, closure decision, antibiotics and LA safety (12 marks, 12 minutes)

A six-year-old is bitten on the dorsum of the hand by the family dog. There is a deep puncture with surrounding bruising. Distal sensation and movement are intact. The child weighs twenty kilograms. The clinician considers primary closure and lidocaine infiltration. [12]

Question. Describe your wound management (irrigation, debridement, and the decision on closure), your antibiotic prophylaxis, tetanus considerations, and the safe local anaesthetic dosing for this child. Explain your reasoning.

Model answer

Wound management (4 marks). Hand bites are heavily contaminated (Pasteurella, Capnocytophaga, anaerobes) and carry a high infection rate. Irrigate copiously with tap water or saline at moderate pressure, debride devitalised tissue, and remove any foreign material (a tooth fragment may be retained — consider a radiograph). Assess tendon, nerve, joint, and bone involvement before any anaesthesia. Do not close primarily; leave the wound open for delayed closure or healing by secondary intention. Tissue adhesive and primary suturing trap infection and are contraindicated. [12]

Antibiotic prophylaxis (2 marks). Give amoxicillin-clavulanate prophylaxis for this hand bite, covering Pasteurella, Capnocytophaga, staphylococci, and anaerobes. Review at forty-eight hours for signs of infection. Consider specialist review for deep or tendon-involving bites. [12]

Tetanus (2 marks). Check the child's immunisation status. For a contaminated bite (a tetanus-prone wound), give a booster if the last dose was more than five years ago, and give tetanus immunoglobulin for an unimmunised or incompletely immunised child according to the local protocol. [1]

Local anaesthetic safety (4 marks). Calculate the maximum dose against the child's weight before drawing up: plain lidocaine three milligrams per kilogram (sixty milligrams, six millilitres of one percent), or lidocaine with adrenaline seven milligrams per kilogram (one hundred and forty milligrams), and bupivacaine two milligrams per kilogram (forty milligrams). Keep a running total of all incremental doses, aspirate before injecting to avoid intravascular delivery, and watch for early signs of local anaesthetic systemic toxicity (perioral tingling, metallic taste, tinnitus, agitation) progressing to seizures and cardiovascular collapse — treat with intravenous lipid emulsion per local protocol. [10]