Why is thiamine given with IV fluids containing glucose in at-risk patients?

Thiamine, also known as vitamin B1, is administered alongside IV fluids that contain glucose in patients at risk for thiamine deficiency, particularly those with a history of chronic alcoholism or malnutrition. This practice is critical because the administration of glucose can precipitate or exacerbate Wernicke's encephalopathy, a serious neurological condition resulting from thiamine deficiency.

When glucose is infused, it can stimulate insulin release, which may lead the body to utilize thiamine more rapidly. Individuals who are already deficient in this vitamin due to various risk factors may not have sufficient thiamine reserves to support the increased metabolic needs prompted by the glucose, leading to a further decrease in thiamine levels and potential neurological complications.

Wernicke’s encephalopathy is characterized by confusion, ophthalmoplegia, and ataxia, and it requires urgent treatment with thiamine to prevent progression to Korsakoff syndrome, a chronic and debilitating condition. Therefore, administering thiamine in conjunction with glucose is a preventive measure to mitigate the risk of developing this serious condition in vulnerable patients.