Mind the Anion Gap with Dr. Tommy Wood

Dr. Tommy Wood is a qualified medical doctor, graduating from Oxford University in 2011. He has a previous Bachelors degree in Natural Sciences and Biochemistry from Cambridge University. After working as a junior doctor in the UK for two years, Dr. Wood is now working towards a Ph.D. in neonatal brain metabolism at the University of Oslo, Norway.

I was inspired to record this interview by the questions I received after people heard my interview with Jimmy Moore in which we review his recent lab work.

To keep in balance, we have both positive and negative ions in the blood. The positive ions (cations) measured on a basic blood chemistry are sodium and potassium. The negative ions (anions) are chloride and bicarbonate. Just to confuse you, bicarbonate is labelled CO2. The anion gap is the sodium plus the potassium minus the chloride and the bicarbonate. Put another way, the anion gap is the unmeasured anions in the blood.

The anion gap is a calculated number and is relevant because the greater the number, the greater the likelihood of an acidosis. The only way to know for sure is to analyse blood gas.

If you have an anion gap greater than 30, then it's very likely you have an acidosis.

In the show, I mention the Khan Academy Chemistry module and Bryan Walsh's Metabolic Fitness Pro training course. Both of these have helped me understand blood chemistry.

Have you run a basic blood chemistry recently? What was your anion gap?