Thiamine as Adjunctive Therapy for Diabetic Ketoacidosis

Thiamine (vitamin B1) is a water-soluble vitamin that plays a key role in aerobic glucose metabolism. Thiamine is a cofactor of pyruvate dehydrogenase (PDH), an enzyme that must be activated for entry into the Krebs Cycle for aerobic metabolism. PDH activity is reduced in thiamine deficient states, resulting in a shift in pyruvate metabolism to the anaerobic pathway. This leads to increased lactate production and acidosis. Thiamine loss in the urine, with consequent thiamine deficiency, is not uncommon in diabetes. The investigators' preliminary studies have found that thiamine deficiency in occurs in as many as 39% of patients with DKA, and that thiamine levels are inversely associated with lactate and acidosis. The investigator hypothesizes that treating DKA patients with intravenous thiamine will lead to faster resolution of acidosis and improved aerobic metabolism. The investigator's secondary hypothesis is that thiamine treatment will shorten stays in the ICU and hospital and lead to utilization of fewer hospital resources.

In this randomized, double-blind, placebo-controlled trial, patients admitted to the hospital with DKA who are enrolled in the study will be randomized to either intravenous thiamine (200mg in 0.9% saline) twice daily for two days or an identical volume of 0.9% saline on the same schedule. The investigator's primary outcome is change in bicarbonate over the 24 hours following enrollment, with measurements at 0, 6, 12, 18, 24 hours, using a linear mixed-effects model. Secondarily, patients will be stratified by Type I and Type II DM. Additionally, a pre-planned sub-analysis of thiamine deficient subjects will be performed.