Case Study 7: Diabetic Ketoacidosis
Carly is a 12-year-old girl who presents to the emergency department after two weeks of polydipsia,
polyuria and a fever.
In the last 24 hours, Carly has complained of abdominal pain and nausea, and has been vomiting.
Over the last 2-3 months she has experienced a 4 kg weight loss.
In ED, she appears quite unwell. She is tachypnoeic with deep sighing respirations and ‘acetone’
She has orthostatic hypotension and she is tachycardic. Her skin is pale, dry and hot to touch.
An arterial blood gas analysis shows a pH of 7.06 and PaCO2 of 10 mmHg which demonstrates the
severity of her acidosis. Her urinalysis is positive for glucose and ketones.
Blood tests show her serum glucose to be 48 mmol/L with an elevated β-hydroxybutyrate (β-HBO)
level of 1.9 mmol/L.
Her serum Na+ has been measured at 128 mmol/L and serum K+ at 6.3 mmol/L.
CRP is elevated as is her WCC which also shows immature band cells.
Carly is drowsy, easily roused but also somewhat irritable. At best her GCS is E3+V4+M5 = 12
She is quickly commenced on IV fluids and an IV insulin infusion with gradual clinical and biochemical
improvement over the next 3-4 hours. Six (6) hours into her resuscitation and treatment, there is a
noticeable neurological deterioration where she becomes highly agitated, and inappropriate.
Subsequently she has self-terminating tonic-clonic seizure and following which she is unarousable.
Her GCS on assessment is 6 and her pupils are dilated but reactive. She is intubated and
administered Mannitol. Over the following 24 hours her GCS gradually improves to the point that
she is extubated, and discharged home a week later with no neurological deficits.
1. Develop a concept map which identifies and links the presentation and pathophysiological
processes that have occurred in Carly, over the time leading up to Carly’s presentation to
2. Explain how these pathophysiological disease processes lead to the observed signs, symptoms
and test results found in this patient after admission to hospital and her subsequent