Simple laceration repair and wound management — branching viva

Branching viva — simple laceration repair and wound management

The examiner releases the stem and then branches into five probes. A strong candidate answers the assessment first, defends the analgesia, chooses the closure method with justification, recites the local anaesthetic doses, and then adapts when the scenario turns to a bite. [1] [8]

Opening (examiner)

"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. Walk me through your management." [1]

Branch 1 — Assessment (expected answer)

Use the MADNESS structure: mechanism (blunt table edge), age of wound, depth and distal neurovascular function, non-accidental-injury check, examine tendon and joint, site and tension, safeguarding and tetanus status. For a face wound, assess the lip vermillion border, facial nerve function, and distal sensation before any anaesthesia, because local anaesthesia masks nerve injury. Take a targeted history including oral intake, immunisation, allergies, and bleeding disorder. [1]

Probe. "She has not eaten for three hours — does that matter?" — Yes, it is relevant if procedural sedation becomes necessary, so document fasting status at the outset even if sedation is not the plan. [2]

Branch 2 — Analgesia (expected answer)

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 by sodium-channel blockade and makes even subsequent infiltration painless. For the child who remains distressed, layer in non-pharmacological measures and consider procedural sedation for a long or complex repair in a monitored setting. [4] [2]

Probe. "Why topical first, rather than just infiltrating?" — Topical anaesthesia reduces the pain of infiltration itself and the procedural distress of the whole encounter, which has lasting behavioural consequences for the child. Evidence supports a topical-first, child-centred approach. [4] [3]

Branch 3 — Closure method (expected answer)

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. Irrigate with tap water (as effective as saline) before closure. Avoid tissue adhesive on mucosa, high-tension skin, bites, or infected wounds. If sutures were chosen for precise cosmesis, use a 6-0 or 5-0 non-absorbable suture on the face, removed at five days. [8] [9]

Probe. "How does the glue actually work?" — The cyanoacrylate polymerises on contact with skin moisture to form a flexible bond that holds the edges together while healing proceeds beneath. It must bond the surface only and never enter the wound, or it traps dead space and invites infection. [8]

Branch 4 — Local anaesthetic safety (expected answer)

If infiltration is needed, calculate the maximum dose against weight before drawing up: plain lidocaine three milligrams per kilogram, lidocaine with adrenaline seven milligrams per kilogram, bupivacaine two milligrams per kilogram. Aspirate before injecting to avoid intravascular delivery, keep a running total, and watch for early signs of local anaesthetic systemic toxicity — perioral tingling, metallic taste, tinnitus, agitation — progressing to seizures and cardiovascular collapse, treated with intravenous lipid emulsion. [10]

Probe. "Why does adrenaline double the safe lidocaine dose?" — Adrenaline causes vasoconstriction, which slows systemic absorption and so raises the maximum from three to seven milligrams per kilogram; it also helps a bleeding field. [10]

Branch 5 — The pivot: a dog bite to the hand (expected answer)

Now the scenario is a six-year-old bitten on the dorsum of the hand. The management changes entirely. Hand bites are heavily contaminated (Pasteurella, Capnocytophaga, anaerobes) and carry a high infection rate, so irrigate copiously, debride devitalised tissue, and assess tendon, nerve, joint, and bone involvement before anaesthesia. Do not close primarily — leave the wound open for delayed closure or secondary intention. Give amoxicillin-clavulanate prophylaxis for this high-risk bite, check tetanus status, and consider rabies for overseas or unprovoked bites. Review at forty-eight hours. [12]

Probe. "Why not just suture it to get a better scar?" — Primary closure of a hand bite traps infection, leading to abscess, tenosynovitis, and a worse scar than healing by secondary intention. [12]

Examiner's wrap

The unifying principle is that the wound's characteristics dictate the method: clean and low-tension means tissue adhesive; high-tension, deep, or precise-cosmesis means sutures; contaminated or a bite means leave it open, irrigate, and give antibiotics. Throughout, the frightened child deserves a topical-first, child-centred approach, because procedural distress has lasting behavioural consequences. [1] [3]