Endocrine emergencies: integrated approach — formative SAQs

SAQ 1 — The undiagnosed young child with new-onset DKA (20 marks, ~15 minutes)

A 4-year-old girl has had two weeks of polyuria, polydipsia and a 3 kg weight loss attributed to a virus. She now presents vomiting, with deep sighing breathing and dehydration. Bedside glucose is 28 mmol per litre, venous pH 7.08, bicarbonate 8 mmol per litre, beta-hydroxybutyrate 5.2 mmol per litre, potassium 5.6 mmol per litre. Corrected sodium is 137 mmol per litre. She is drowsy but rousable. [1]

Questions

1. Give the diagnosis, the severity grading, and two reasons why the diabetes was missed for two weeks. (5 marks) [1]
2. Outline the first-hour resuscitation with the specific fluid, insulin and potassium plan, and state two things that must NOT be done. (6 marks) [1] [4]
3. Four hours into treatment she develops a headache and becomes drowsier, with a heart rate of 60 and a blood pressure of 130 over 90. Give the diagnosis and the immediate management. (5 marks) [3] [14]
4. Describe the sick-day plan you teach the family before discharge, and the structured follow-up you arrange. (4 marks) [1]

Model answer (must-hit)

1. This is severe DKA (pH below 7.1, bicarbonate below 10) from new-onset type 1 diabetes. The diabetes was missed because the polyuria was attributed to a viral illness and the weight loss to a poor appetite, and because a bedside glucose was not checked at the earlier presentations. The young child under five presents more often in DKA because the symptoms are non-specific and the metabolic collapse is rapid. [1]
2. Resuscitate in three steps: give 10 mL per kg of 0.9 per cent saline only if she is in shock (she is drowsy and dehydrated, so a bolus is reasonable); start an insulin infusion at 0.05 to 0.1 units per kg per hour AFTER the first fluid — never as a bolus; and add potassium at 40 mmol per litre in the maintenance fluid once the serum level is known and she is urinating. Two things that must NOT be done: insulin must NEVER be given as a bolus (dangerous hypokalaemia and cerebral-oedema risk), and bicarbonate must NOT be given (it increases cerebral-oedema risk). [1] [4]
3. The headache, altered consciousness and the bradycardia with hypertension (the Cushing response) are cerebral oedema until proven otherwise. Treat immediately: give mannitol 0.5 to 1 g per kg or 3 per cent hypertonic saline 2 to 5 mL per kg, reduce the fluid rate by one third, and prepare for intubation and ventilation. Do NOT wait for a CT scan to treat. Cerebral oedema complicates roughly 0.5 to 1 per cent of paediatric DKA episodes and carries a 20 to 40 per cent mortality. [3] [14]
4. Teach the sick-day plan: never stop insulin during illness, check glucose and ketones every 2 to 3 hours, give correction insulin if ketones rise, maintain hydration with sugar-free fluids, and present early if vomiting or drowsy. Arrange structured follow-up with paediatric diabetes, a diabetes educator, a dietitian and a psychologist, with a school care plan and a MedicAlert. [1]

SAQ 2 — The sick child with an endocrine clue (20 marks, ~15 minutes)

You are the paediatric registrar covering the emergency department. Three children arrive over a shift, each testing the integrated approach to endocrine emergencies. [5]

Questions

1. A 9-year-old boy who stopped his oral steroid six weeks ago presents with a fever, vomiting, drowsiness, and shock unresponsive to a 20 mL per kg saline bolus. Glucose is 1.8 mmol per litre, sodium 130, potassium 4.1. Give the diagnosis, the one bedside clue that distinguishes it from primary adrenal failure, and the immediate treatment. (5 marks) [5] [6]
2. A 14-year-old girl with a goitre and a stopped carbimazole presents with a fever of 39.8, a heart rate of 170 in atrial fibrillation, and agitation. Give the diagnosis and the four-track management. (5 marks) [7]
3. A 7-year-old boy with meningitis becomes drowsy and seizes. His sodium is 118, he is euvolaemic, and the urine osmolality is 320 mOsm per kg. Give the diagnosis and the immediate treatment for the seizure, and the correction rate to target thereafter. (6 marks) [10]
4. Explain the shared resuscitation principle that unifies all three emergencies, and name the two bedside tests that make the integrated approach work. (4 marks) [1] [5]

Model answer (must-hit)

1. This is glucocorticoid-induced secondary adrenal crisis. The single bedside clue is the normal potassium (4.1 mmol per litre) — aldosterone is preserved in secondary disease because it is governed by the renin-angiotensin system rather than by ACTH, so the salt-wasting and hyperkalaemia of primary failure are absent. The immediate treatment is intravenous hydrocortisone 50 to 100 mg stat with ongoing fluids and dextrose. One dose of empiric hydrocortisone is harmless if wrong and life-saving if right. [5] [6]
2. This is thyroid storm. The four-track management is: beta-blockade (propranolol), block new hormone synthesis (carbimazole or propylthiouracil), block peripheral T4-to-T3 conversion (hydrocortisone or dexamethasone), and active cooling with treatment of the precipitant. Give the beta-blocker cautiously if there is heart failure. Thyroid storm is rare in children but carries a significant mortality. [7]
3. This is SIADH secondary to a CNS insult, presenting with symptomatic hyponatraemia and seizure. The immediate treatment for the seizure is 3 per cent hypertonic saline at 2 mL per kg over 10 minutes, repeated once if still seizing — the seizure is terminated by raising the sodium by 3 to 5 mmol per litre. Thereafter correct slowly — no more than 8 to 10 mmol per litre in 24 hours — to avoid osmotic demyelination. [10]
4. The shared resuscitation principle is ABCDE, intravenous access, bedside glucose and blood gas, and then the empiric life-saving therapy before the confirmatory endocrine test returns — because the test confirms but does not resuscitate. The two bedside tests that make the integrated approach work are the bedside glucose (which splits DKA, hypoglycaemia and the rest) and the venous blood gas with electrolytes (which splits the acidosis, the sodium and the potassium pattern). Together they take two minutes and split the four emergencies within them. [1] [5]