A 65 year old female is brought to ED via ambulance on a priority 1. According to the paramedics the patient has taken an overdose of benzodiazepines and alcohol. Her GCS is 3 and the team is preparing to intubate the patient. The following ECG is obtained prior to intubation:
pH 7.31 Na 148 mmol/l
pCO2 16 mmHg K 1.2 mmol/l
pO2 46 mmHg Cl 136 mmol/l
HCO3 8.3 mmol/l BSL 1.5 mmol/l
B/E -16.8 Cr 17 umol/l
Lactate 0.3 HB 46 mmol/l
- Describe and interpret the VBG
- What would be your next step in management of this patient?
Acidosis
Primary metabolic acidosis as HCO3 is low (< 22) and CO2 is also low (<35) to compensate
It is a NAGMA as AG < 16 (in fact it is low)
Is there a concomittant respiratory component – expected CO2 = 24 (close enough) – there the patient is ventilating very well. Not fitting with benzo and EtOH ingestion
Also note severe hypokalaemia and hypoglycaemia.
This patient needs 50mL 50% dex and repeat BSL's along with potassium (at least 30mmol) and magnesium to assist in potassium uptake.