Oesophagitis, caustic ingestion and oesophageal injury — formative SAQs

SAQ 1 — The toddler with a suspected oesophageal button battery (20 marks, ~15 minutes)

A previously well 18-month-old girl is brought in with sudden drooling, refusal to feed and a fussy cough for two hours. Her older sibling's toy has an open battery compartment and a 20 mm lithium coin cell is missing. She is not in respiratory distress and her observations are stable. [1]

Questions

1. State the most likely diagnosis and why it is a time-critical emergency. (4 marks) [1]
2. Describe the first investigation and the specific radiological signs that confirm the diagnosis and distinguish it from a coin. (4 marks) [1]
3. Outline your immediate management, including any pre-removal measure and its eligibility, and the definitive step and its timing. (6 marks) [2]
4. State the delayed complications you must anticipate and how long the risk lasts. (3 marks) [1]
5. State the counselling you give the family at discharge. (3 marks) [1]

Model answer (must-hit)

1. The most likely diagnosis is an oesophageal button battery. It is a time-critical emergency because an intact lithium coin cell lodged against the moist mucosa completes an electrical circuit, generates hydroxide at its negative pole, and produces a liquefactive alkaline burn that begins within two hours; the injury can become transmural and erode into the trachea or aorta, so the battery is removed within two hours rather than observed. [1]
2. The first investigation is an urgent plain radiograph of the neck, chest and abdomen. A button battery shows a halo or double-ring sign on the frontal (anteroposterior) view and a step-off on the lateral view, which distinguishes it from a coin; the lateral view also shows the orientation of the narrow negative pole, which is the site of the deepest burn and the wall at greatest risk. [1]
3. Escalate immediately for emergent endoscopic removal within two hours of ingestion, keeping the child nil by mouth and calling the endoscopy and anaesthetic teams. While theatre is prepared, give a pre-removal mitigation because this child is eligible — older than twelve months, within twelve hours of ingestion, and able to swallow — with honey 10 mL orally every 10 minutes for up to six doses to buffer the alkaline burn; sucralfate suspension is the in-hospital alternative. Neither is given if there is suspected perforation, sepsis or airway compromise, and neither delays removal. [2]
4. Anticipate delayed complications: tracheo-oesophageal fistula, aorto-oesophageal fistula with catastrophic bleeding, oesophageal perforation and mediastinitis, stricture, vocal cord paralysis and spondylodiscitis. The aorto-oesophageal fistula can present with fatal bleeding up to about three weeks after the battery is removed, so the risk period extends well beyond the removal itself. [1]
5. Counsel the family that removal ends the burn but not the risk, and that they must return immediately if the child vomits blood or has any bleeding, because a sentinel bleed may herald a fatal aorto-oesophageal fistula for up to three weeks. Give injury-prevention advice about securing battery compartments and storing loose lithium cells out of reach, and arrange the planned follow-up. [1]

SAQ 2 — The toddler with a caustic ingestion (20 marks, ~15 minutes)

A 2-year-old boy is brought in one hour after drinking from an unlabelled bottle that his father had used to decant drain cleaner. He is drooling, distressed and refusing to swallow, with burns on his lips and tongue, but is not stridulous. [7]

Questions

1. State the type of injury this agent causes and the mechanism, and whether the absence of stridor reassures you. (4 marks) [8]
2. List three things you must NOT do, with the reason for each. (6 marks) [7]
3. Outline your immediate management and the timing and purpose of endoscopy. (5 marks) [9]
4. Explain how the endoscopic findings guide the plan and prognosis. (3 marks) [9]
5. State the most serious long-term complication and its implication. (2 marks) [7]

Model answer (must-hit)

1. Drain cleaner is a strong alkali, which causes liquefactive necrosis: it dissolves cell membranes and saponifies fats, so the burn penetrates deeply and can become transmural with perforation, unlike an acid, which coagulates surface proteins into a limiting eschar. The absence of stridor does not reassure me, because airway oedema can develop over hours; I reassess the airway repeatedly and keep an experienced airway operator available, and the absence of oral findings would not have excluded oesophageal injury either. [8]
2. Do not induce vomiting, because it re-exposes the oesophagus to the corrosive; do not give a neutralising acid or alkali, because the exothermic reaction adds a thermal burn to the chemical one; and do not pass a blind nasogastric tube, because it can perforate the softened, burned wall. Dilution with water or milk is also not recommended once the child is in hospital. [7]
3. Secure and monitor the airway, keep the child strictly nil by mouth, and give analgesia and intravenous fluids. Arrange endoscopy at twelve to twenty-four hours after ingestion: this timing lets the burn declare its true depth while avoiding the very early window that underestimates injury and the second-week window when the friable wall perforates easily. Endoscopy grades the burn and directs the plan. [9]
4. The endoscopic findings are graded on the modified Zargar scale. Grade 1 and 2a burns heal without sequelae and the child can be fed and discharged with follow-up. Grade 2b and 3 burns carry a high risk of stricture, so they are managed with prolonged nutritional support and a surveillance and dilatation programme; corticosteroids to prevent stricture remain controversial and are not routine. [9]
5. The most serious long-term complication is oesophageal squamous cell carcinoma, whose risk is increased roughly a thousandfold or more decades after a severe alkali burn; this implies lifelong awareness and a role for late endoscopic surveillance, alongside the shorter-term stricture and dilatation burden. [7]