New tool to gauge delirium severity in ICU patients
Many older patients in intensive care experience delirium, but until now it has been difficult for health care workers to gauge the severity of each patient’s condition. Now researchers from the Indiana University (IU) Center for Aging Research have developed a new easy-to-use tool designed to score and track delirium severity in the intensive care unit (ICU), helping health care workers make better decisions about the brain health of ICU patients.
Delirium is a rapid change in brain function, characterized by confusion and long-term memory problems. It occurs in approximately three-quarters of ICU patients and is associated with longer ICU and hospital stays, increased costs of care and higher death rate.
Known risk factors for developing delirium in the ICU include age, pre-existing cognitive impairment, and sedation which is often used in conjunction with mechanical ventilation.
Typically ICU patients are checked twice daily for symptoms of delirium, however the universally used “yes” or “no” tests do not indicate severity. In addition, current measures to gauge delirium severity are cumbersome and seldom administered because they are difficult to use in ICU patients on ventilators and require advanced staff training.
The new tool developed by the IU Center for Aging Research investigators is called the Confusion Assessment Method for the Intensive Care Unit 7 — the CAM- ICU-7 for short. It is an easy-to-use delirium severity instrument that scores severity on a scale of zero to seven and is useable with all ICU patients, including those on mechanical ventilation.
Scores of one to two indicate no delirium; three to five represent mild to moderate delirium and six to seven signify severe delirium. Clarifying delirium severity can indicate whether the therapeutic regime has been effective or not and can have implications for a patient’s prognosis.
“Not enough emphasis has been placed on assessing delirium severity in the ICU because there is a lack of understanding of how significant outcomes of delirium are for patients,” said study leader Babar A. Khan, M.D., a critical care medicine physician and an implementation scientist with the Indiana Clinical and Translational Sciences Institute’s IU Center for Health Innovation and Implementation Science.
“The CAM-ICU-7 provides needed objectivity to brain failure assessment and information necessary for current and future brain health management.
In the absence of a scale to assess delirium severity, healthcare workers saw only black and white and there was no gray area. Having an instrument that can further define the “yes” of delirium into severe or mild to moderate delirium can help reveal whether the treatments are working for the patient and offer insight into prognosis.
“This new tool has the potential to essentially revolutionize the way delirium care is practiced in the ICU,” said Khan. “Nobody had previously cracked the code of how to assess delirium severity in the ICU efficiently and we have come up with an innovative instrument that is easily doable. Adding it to and augmenting what clinicians are already comfortable with makes the quick adoption of the CAM-ICU-7 seamless.
“When a patient experiences acute renal failure, clinicians can see if urine output is improving or if serum creatinine is decreasing. But until the CAM-ICU-7 there were no similar ways to monitor disease progression in acute brain failure.”
The study was conducted in ICUs at hospitals in the Eskenazi Health and Indiana University Health systems. Average age of the 518 study participants was 60; 55 percent were women and 45 percent were African-Americans; 58 percent required mechanical ventilation. The average length of ICU stay was 14 days.
The research is published in the journal Critical Care Medicine.