A 17 year old male is brought to your ED by his mum. She noticed that he has been irritable and slightly confused for the last few hours. He has been vomiting and had some loose stools for the last 3 days.

Vitals:

BP 120/70

PR 100/min

RR  26/min

His VBG:

pH   7.515   (7.36-7.44)

pCO2    31.0   (35-45 mmHg)

pO2    42.1   (80-100 mmHg)

BE   2.8   (-2–+2)

HCO3  24.9  (24+/-2 mmol/l)

Hb    129   (140-160  g/l)

COHb   1.0%

MetHb  0.9%

Na   134   (137-145 mmol/l)

K   2.4   (3.5-5  mmol/l)

Cl    96    (99-111 mmol/l)

Glu   7.3   (4-6 mmol/l)

Lac    5.5   mmol/l

Creat  76  (<130 umol/l)

Questions:

1. Describe the abnormalities

2. Give a reasonable differential diagnosis

3. What are the immediate treatment priorities?

4. What two tests are probably the most important?

Thanks to Michael Lovegrove for this case