DKA DOESN'T BENEFIT FROM NaHCO3

The Evidence:

RCT 21 patients with DKA, pH=6.9 to 7.14. Randomized to NaHCO3(pH<7.0: 3 amps, 7.0-7.09: 2 amps,>=7.10: 1 amp). CSF followed in some patients. F/U to 12 hrs of glucose, ketones, HCO3 and pH, with NO DIFFERENCE in any of these parameters. Time to HCO3=15, pH=7.3 and glucose=14 equal in both groups. RCT 32 patients with DKA, pH<7.2. F/U 2 hrs only, for glucose, ketones, lactate: no diff. PH and HCO3 showed greater increases with bicarbonate treatment at 2 hrs. RCT 20 patients with DKA, pH<7.15. 24 hrs follow-up. PH and bicarb showed greater increase at 2 hrs.

Comments:

1. CSF pH in severe DKA is well protected by blood-brain barrier. In trial [1] and [4], CSF pH done during acute DKA. While blood pH<7.1, CSF pH approx. 7.3
2. Worry of bicarb causing decrease in resp drive due to alkalotic load, thereby causing an increase in PaCO2 and a worsening of intracellular and CSF acidosis. Also amp. bicarb's PCO2 is approx 600, so direct CO2 load!

References:

1. Morris LR, Murphy MB, Kitabchi AE. Bicarbonate therapy in severe diabetic ketoacidosis. Ann Int Med 1986;105:836-840.
2. Hale PJ, Crase J, Nattrass M. Metabolic effects of bicarbonate in the treatment of dka. BMJ 1984;289:1035-1038.
3. Gamba A, Oseguera J, et al. Bicarbonate therapy in severe diabetic ketoacidosis. a double blind, randomized, placebo controlled trial. Rev Invest Clin 1991;43(3):234-238.
4. Ohman JL, Marliss EB, et al. The CSF in DKA. N Engl J Med 1971;284:283-290.

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