A 28-year-old woman with type 1 diabetes presents with a 2-day history of vomiting and polyuria after running out of insulin. She appears dehydrated with deep, sighing respirations. BP 95/60 mmHg, HR 115 bpm, Temp 37.2°C, RR 28/min, GCS 14/15.
Venous blood gas: pH 7.18 Glucose 28.5 mmol/L Bicarbonate 11 mmol/L Blood ketones 5.2 mmol/L Sodium 132 mmol/L Potassium 5.8 mmol/L
According to the Joint British Diabetes Societies (JBDS) guidelines, what is the MOST appropriate initial fluid strategy?
0.9% sodium chloride 500ml stat bolus, then 1L over 1 hour
0.45% sodium chloride with 5% dextrose 1L over 1 hour
0.9% sodium chloride 1L over 1 hour without potassium
Hartmann's solution 1L over 1 hour with 40mmol KCl
0.9% sodium chloride 1L stat bolus, repeated twice