Elderly surgical patients are more likely to suffer from debilitating postoperative delirium if they have diabetes, undergo longer surgery or respond poorly to stress, according to a small study.
The research, presented Oct. 14 in San Francisco at the annual meeting of the American Society of Anesthesiologists, could help clinicians prevent postoperative delirium, which can lead to longer hospital stays, poor recovery and higher death rates, the study authors said.
The incidence of postoperative delirium ranges from 2% to 33% in elderly patients undergoing major surgery, depending on the patients risk factors and the degree of operative stress, according to background information for the study. Patients who have postoperative delirium can suffer from fluctuating inattention, disorientation, lethargy, agitation and combative behavior.
In addition to how disturbing this complication is for patients and their families, its also associated with death during surgery and increased medical costs, Stacie G. Deiner, MD, associate professor in the Department of Anesthesiology, Geriatrics and Palliative Care, and Neurosurgery at the Mount Sinai Icahn School of Medicine in New York City, said in a news release.
Studies have shown that patients with postoperative delirium have two to five times the risk of major complications including death. To be able to identify, predict or understand the mechanism of postoperative delirium could help us identify ways to prevent it.
The study involved cognitive testing for 76 patients ages 68 or older who had major non-cardiac surgery. The patients were assessed daily using the Confusion Assessment Method and the Mini Mental Status Exam. Blood was collected and tested for cortisol, epinephrine and norepinephrine hormone levels before surgery, just before removing the breathing tube used during surgery and two hours after surgery.
The study found that higher adrenal response levels two hours after the start of surgery, diabetes and the length of the surgery were highly predictive of postoperative delirium.
“These results suggest that intraoperative stress is an important predictor of [postoperative delirium],” the authors wrote. “[Diabetes mellitus] may be a marker for patients with preexisting frailty e.g. intracerebral microvascular disease.”
Said Deiner: By understanding who may be at high risk for postoperative delirium, we can work on interventions for these patients, such as considering giving them antipsychotic medications before surgery, carefully monitoring the depth of anesthesia and/or having patients see a geriatrics specialist prior to surgery.”
Patients will be reexamined with full cognitive battery at three and six months for persistent cognitive dysfunction, the authors wrote.
Study abstract: http://bit.ly/16c0aFu