Researchers in Oregon, of the U.S. Northwest Pacific, have identified a test that can predict which surgical candidates are most at risk of delirium, or acute confusion and disorientation, a common complication following surgery in older patients.
The screening tool, claimed to be quick and simple by researchers from the Veterans Affairs Portland Health Care System (VAPORHCS) together with those at Oregon State University (OSU) and Oregon Health & Science University (OHSU), was developed by Dr. Soo Borson at the University of Washington to detect dementia.
The new research found that one way of using and scoring the test, known as the "Mini-Cog," offered high predictive accuracy of delirium following elective surgery with major anesthesia.
Now a 150 billion U.S. dollars problem across America, delirium can lead to slower recovery, a long-term worsening of memory and thinking, and even death after surgery. Its incidence ranges from 7-10 percent in older adults after simple elective surgery, rising to at least half of older adults undergoing emergency, cardiac or orthopedic surgery. Individuals who develop delirium are more likely to be debilitated, require skilled nursing care, and die in the year after surgery.
Therefore, identification of those most at risk could help guide decisions about whether or not to have surgery, and allow prompt, low-cost interventions after surgery to help prevent this problem.
"Before this study, identifying people at risk for delirium following surgery required complicated or time-consuming evaluations," said Dr. Sarah Goodlin, the lead VAPORHCS investigator for the study. "Now we believe we can identify people at high risk and help physicians make informed decisions with their patients about the hazards and benefits of pursuing elective surgery."
As it takes about 2-3 minutes, the Mini-Cog test can be done in any language and has no ethnic, educational or cultural barriers. Told three ordinary words and asked to repeat them, such as "apple," "watch" and "penny," patients are then asked to draw a simple clock face, including the numbers and hands set to a specific time. Finally, they are asked to repeat the three words they were told.
The researchers scored the Mini-Cog from 0-5. A person gets 2 points for correctly drawing a clock and time; and 1 point each for recalling the three words. According to the study, a person with a score of 0-1 had a 50 percent or greater probability of post-operative delirium. Those with a score of 3 had a 20 percent probability; a score of 4 a 13 percent probability; and a score of 5 less than 5 percent probability of delirium after surgery.
While the study was based on findings from 76 veterans age 65 or older who were almost exclusively male, Goodlin was quoted as saying in an OSU news release that further research will be needed to confirm the findings and broaden them to other groups.
However, in their study published in the Journal of the American Geriatric Society, the researchers noted that medical care is more effective at preventing delirium, especially in people at moderate risk, than in treating it once it develops. That makes a predictive tool all the more helpful.
