Medical and endocrine disease03 / 30
Diabetic ketoacidosis with suspected testicular torsion19-year-old man, 70 kg; 5 hours of severe left scrotal pain
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Know this first
- DKA needs all three: ketones, glucose over 250 mg/dL, and a wide-gap acidosis with HCO3 under 18 or pH under 7.3.
- Insulin at 0.1 units/kg/h starts only once potassium is above 3.3.
- Potassium reaches its lowest point 2–4 hours after IV insulin starts.
- Bicarbonate is considered only if pH is below 6.9.
- Wide-complex tachycardia with SBP below 80 or altered mentation needs immediate synchronised cardioversion.
The patient
19-year-old man, 70 kg; 5 hours of severe left scrotal pain; urology want to explore for torsion now.
Type 1 diabetes; his insulin pump stopped 2 days ago during a stomach bug; vomiting, dry, deep sighing breaths.
Venous gas: pH 7.08, HCO3 7 mmol/L, glucose 486 mg/dL, K 5.4 mmol/L, anion gap 28, ketones strongly positive.
Vitals: BP 98/56, HR 128, SpO2 98% on air, RR 32, temp 37.6 °C.
The examiner asks
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Consider
What are the issues?
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- A 19-year-old in severe DKA who needs time-critical scrotal exploration for torsion. Patient
- Two clocks run: his testis loses viability by the hour, and his acidosis can kill him. Stem trigger
- He has the full triad: ketonaemia, glucose 486 and a pH of 7.08 with a wide gap. Disease
- Pain, ileus and vomiting are common in DKA itself, so the surgeon confirms the scrotum is the problem.
- His pump failure during gastroenteritis is the trigger; he's several litres dry.
Prepare
How do you resuscitate him before theatre?
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- Normal saline 1–2 L over the first 1–2 hours, then 15–20 mL/kg/h. (Disease)
- Potassium is 5.4, above 3.3, so fixed-rate insulin starts at 0.1 units/kg/h.
- K 5.4: no potassium yet. Once below 5.3 with urine flowing, 20–40 mEq per litre.
- Once his glucose is down to 250 mg/dL, dextrose 5% joins at 100 mL/h; insulin carries on.
- No bicarbonate: his pH is above 6.9.
- Glucose, ketones, potassium and pH rechecked hourly; potassium dips most 2–4 hours in.
Plan
When and how do you anaesthetise him?
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- Urgency comes first: I resuscitate while theatre is set up, then we go together with urology. Surgery
- Vomiting, probable ileus: a rapid sequence, rocuronium 1.2 mg/kg. Airway
- A small, titrated induction dose; he's volume depleted and deeply acidotic. Disease
- Winter's formula puts his expected PaCO2 near 18–19 mmHg; I ventilate to keep that compensation.
- A short operation, then HDU with the diabetes team. After surgery
Crisis
Two hours after insulin started, in recovery, he has ectopics then a regular broad-complex tachycardia at 190. He's drowsy, BP 76/40, pulse present. K 2.6 mmol/L. What do you do?
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- Tachycardia-with-a-pulse algorithm: broad, regular, at 190, driven by his falling potassium. Crisis
- Unstable? Yes, SBP under 80 and drowsy: synchronised cardioversion at 50–100 J biphasic, with sedation.
- If it recurs once he's stable: amiodarone 150 mg over 10 minutes.
- His cause is hypokalaemia: 20–40 mEq over 3–10 minutes, by central line if possible.
- Magnesium 1–2 g over 15 minutes alongside it.
- Insulin paused until potassium is back above 3.3, with fluids running, then HDU. After surgery
Fatal mistakes
- Starting insulin while his potassium is below 3.3.
- Giving a full induction dose into profound acidosis and hypovolaemia.
- Giving routine bicarbonate when his pH is above 6.9.
Checked against: Barash 9e · Miller 10e · AHA guidelines: adult advanced life support (2025) · Stoelting 8e
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