Thiamine Deficiency -A Rare Cause of Difficult Sedation Weaning in ICU

Thiamine insufficiency might be the cause of delirium and sedative dependency in critically sick patients, making weaning from sedation and mechanical breathing more difficult. Other medical problems, such as stroke, drug overdose, other types of encephalopathy, and infections like meningitis, may all seem like Wernicke's encephalopathy (WE). These conditions should be properly investigated, even more so in individuals at low risk of developing WE. In high-risk individuals, such as those with severe illness or sepsis, WE may be induced by increased metabolic demand, resulting in relative thiamine shortage. Absolute thiamine deficiency may arise in cancer patients as a result of malabsorption, starvation, or vomiting, resulting in WE. Recently published case report showed how thiamine supplementation aided the patient in weaning off sedation and MV and improved the delirious condition.

Due to increasing clinical deterioration associated with ARDS and hypoxia, a 54-year-old male patient was intubated and placed on mechanical ventilation. A BAL sample verified the presence of H1N1-associated respiratory distress syndrome (ARDS) lung pneumonia. Sedation was maintained with Midazolam, Fentanyl, and Propofol, and a paralytic agent was added to regulate breathing with a high FIO2 need. Tazocin, Tamflu, and Levofloxacin were administered, with Meropenem and Linezolid added later in the ICU day 8. To synchronise with MV, sedation was raised to 150 mcg Fentanyl, 5 mg midazolam, 1 mcg/kg/hr Precedex, and 100 mg Propofol. Later, Fentanyl was reduced to 80mcg, midazolam to 4 mg, propofol was discontinued, Precedex remained unchanged, and Seroquel 25 mg TID was introduced. After ten days of mechanical ventilation, the patient recovered significantly in terms of ARDS on PEEP 7, FIO2 40%, but remained profoundly sedated and demonstrated difficulty to wean from sedation. Seroquel was raised to 50 mg TID and Clonidine was administered to aid in weaning from sedation, however the patient was unable to wean completely due to hyperactive delirium. The LP was performed on the neurologist's suggestion, but the results were normal. The ICU staff chose to provide Thiamine 100 mg daily for three days as a preliminary diagnosis of Wernicke's encephalopathy. After two doses, the patient demonstrated substantial improvement in terms of weaning off sedation and was successfully weaned off of both sedation and MV.

This example demonstrates that the commonly seen condition of ICU delirium may be caused by thiamine deficiency, which is usually overlooked. ICU delirium occurs often in critically ill patients due to a variety of causes, including sedative-induced delirium, postanesthesia delirium, and critical disease delirium caused by hypoxia, infection, or medication intoxication. Thiamine insufficiency is fairly uncommon in severely unwell patients. Thiamine insufficiency should be considered a possible cause of delirium in the intensive care unit. Thiamine should be administered empirically to ICU patients; it has been shown to be beneficial.

Reference –

Aly MK (2021) Acute Delirium and Difficult Sedation Weaning in ICU Thiamine Deficiency Maybe a Possible not Uncommon Cause. Int J Crit Care Emerg Med 7:131. doi.org/10.23937/2474-3674/1510131