Paediatricscommon
A three-year-old boy weighing 15 kg is brought to the emergency department 90 minutes after his parents found him with an open bottle of perfume containing 60% ethanol; about 30 mL is missing. He is drowsy but rousable and smells of alcohol. His respiratory rate is 24 per minute, oxygen saturation 98% on air, heart rate 120 per minute and temperature 36.6 degrees Celsius. He is admitted for observation. Which one of the following should be measured repeatedly while he is observed?