Temperature variability during delirium in ICU patients: an observational study

Area of Science:

• Critical Care Medicine
• Neuroscience
• Physiology

Background:

• Delirium is a common and serious condition in the intensive care unit (ICU), characterized by acute disturbances in consciousness and cognition.
• It is associated with poor long-term outcomes but is often under-recognized by healthcare professionals.
• Current detection methods rely on screening tools, highlighting the need for novel monitoring approaches like physiological signal analysis.

Purpose of the Study:

• To investigate the relationship between intensive care unit (ICU) delirium and temperature variability, a measure of thermoregulation.
• To determine if absolute body temperature is also associated with ICU delirium.
• To explore novel physiological markers for delirium detection.

Main Methods:

• A study included ICU patients who experienced both delirium and delirium-free days, assessed using the Confusion Assessment Method for the ICU.
• Daily temperature variability was calculated using the mean absolute second derivative of the temperature signal.
• Linear mixed models compared temperature variability and absolute body temperature between delirium and non-delirium days, adjusting for sedation and organ failure scores.

Main Results:

• Temperature variability was significantly increased on delirium days compared to non-delirium days (p<0.001), even after adjusting for confounders.
• No significant association was found between delirium and absolute body temperature.
• The findings remained consistent after adjusting for confounding factors.

Conclusions:

• Increased temperature variability is a potential physiological marker associated with intensive care unit (ICU) delirium.
• Monitoring temperature fluctuations may offer a new avenue for detecting delirium in critically ill patients.
• Absolute body temperature does not appear to be a reliable indicator of delirium in this context.